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Sample records for meta-analysis effect sizes

  1. Meta-Analysis of Effect Sizes Reported at Multiple Time Points Using General Linear Mixed Model

    Science.gov (United States)

    Musekiwa, Alfred; Manda, Samuel O. M.; Mwambi, Henry G.; Chen, Ding-Geng

    2016-01-01

    Meta-analysis of longitudinal studies combines effect sizes measured at pre-determined time points. The most common approach involves performing separate univariate meta-analyses at individual time points. This simplistic approach ignores dependence between longitudinal effect sizes, which might result in less precise parameter estimates. In this paper, we show how to conduct a meta-analysis of longitudinal effect sizes where we contrast different covariance structures for dependence between effect sizes, both within and between studies. We propose new combinations of covariance structures for the dependence between effect size and utilize a practical example involving meta-analysis of 17 trials comparing postoperative treatments for a type of cancer, where survival is measured at 6, 12, 18 and 24 months post randomization. Although the results from this particular data set show the benefit of accounting for within-study serial correlation between effect sizes, simulations are required to confirm these results. PMID:27798661

  2. Standardizing effect size from linear regression models with log-transformed variables for meta-analysis.

    Science.gov (United States)

    Rodríguez-Barranco, Miguel; Tobías, Aurelio; Redondo, Daniel; Molina-Portillo, Elena; Sánchez, María José

    2017-03-17

    Meta-analysis is very useful to summarize the effect of a treatment or a risk factor for a given disease. Often studies report results based on log-transformed variables in order to achieve the principal assumptions of a linear regression model. If this is the case for some, but not all studies, the effects need to be homogenized. We derived a set of formulae to transform absolute changes into relative ones, and vice versa, to allow including all results in a meta-analysis. We applied our procedure to all possible combinations of log-transformed independent or dependent variables. We also evaluated it in a simulation based on two variables either normally or asymmetrically distributed. In all the scenarios, and based on different change criteria, the effect size estimated by the derived set of formulae was equivalent to the real effect size. To avoid biased estimates of the effect, this procedure should be used with caution in the case of independent variables with asymmetric distributions that significantly differ from the normal distribution. We illustrate an application of this procedure by an application to a meta-analysis on the potential effects on neurodevelopment in children exposed to arsenic and manganese. The procedure proposed has been shown to be valid and capable of expressing the effect size of a linear regression model based on different change criteria in the variables. Homogenizing the results from different studies beforehand allows them to be combined in a meta-analysis, independently of whether the transformations had been performed on the dependent and/or independent variables.

  3. Coordinate based random effect size meta-analysis of neuroimaging studies.

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    Tench, C R; Tanasescu, Radu; Constantinescu, C S; Auer, D P; Cottam, W J

    2017-06-01

    Low power in neuroimaging studies can make them difficult to interpret, and Coordinate based meta-analysis (CBMA) may go some way to mitigating this issue. CBMA has been used in many analyses to detect where published functional MRI or voxel-based morphometry studies testing similar hypotheses report significant summary results (coordinates) consistently. Only the reported coordinates and possibly t statistics are analysed, and statistical significance of clusters is determined by coordinate density. Here a method of performing coordinate based random effect size meta-analysis and meta-regression is introduced. The algorithm (ClusterZ) analyses both coordinates and reported t statistic or Z score, standardised by the number of subjects. Statistical significance is determined not by coordinate density, but by a random effects meta-analyses of reported effects performed cluster-wise using standard statistical methods and taking account of censoring inherent in the published summary results. Type 1 error control is achieved using the false cluster discovery rate (FCDR), which is based on the false discovery rate. This controls both the family wise error rate under the null hypothesis that coordinates are randomly drawn from a standard stereotaxic space, and the proportion of significant clusters that are expected under the null. Such control is necessary to avoid propagating and even amplifying the very issues motivating the meta-analysis in the first place. ClusterZ is demonstrated on both numerically simulated data and on real data from reports of grey matter loss in multiple sclerosis (MS) and syndromes suggestive of MS, and of painful stimulus in healthy controls. The software implementation is available to download and use freely. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Effect size calculation in meta-analyses of psychotherapy outcome research.

    Science.gov (United States)

    Hoyt, William T; Del Re, A C

    2018-05-01

    Meta-analysis of psychotherapy intervention research normally examines differences between treatment groups and some form of comparison group (e.g., wait list control; alternative treatment group). The effect of treatment is normally quantified as a standardized mean difference (SMD). We describe procedures for computing unbiased estimates of the population SMD from sample data (e.g., group Ms and SDs), and provide guidance about a number of complications that may arise related to effect size computation. These complications include (a) incomplete data in research reports; (b) use of baseline data in computing SMDs and estimating the population standard deviation (σ); (c) combining effect size data from studies using different research designs; and (d) appropriate techniques for analysis of data from studies providing multiple estimates of the effect of interest (i.e., dependent effect sizes). Clinical or Methodological Significance of this article: Meta-analysis is a set of techniques for producing valid summaries of existing research. The initial computational step for meta-analyses of research on intervention outcomes involves computing an effect size quantifying the change attributable to the intervention. We discuss common issues in the computation of effect sizes and provide recommended procedures to address them.

  5. Bridging meta-analysis and the comparative method: a test of seed size effect on germination after frugivores' gut passage.

    Science.gov (United States)

    Verdú, Miguel; Traveset, Anna

    2004-02-01

    Most studies using meta-analysis try to establish relationships between traits across taxa from interspecific databases and, thus, the phylogenetic relatedness among these taxa should be taken into account to avoid pseudoreplication derived from common ancestry. This paper illustrates, with a representative example of the relationship between seed size and the effect of frugivore's gut on seed germination, that meta-analytic procedures can also be phylogenetically corrected by means of the comparative method. The conclusions obtained in the meta-analytical and phylogenetical approaches are very different. The meta-analysis revealed that the positive effects that gut passage had on seed germination increased with seed size in the case of gut passage through birds whereas decreased in the case of gut passage through non-flying mammals. However, once the phylogenetic relatedness among plant species was taken into account, the effects of gut passage on seed germination did not depend on seed size and were similar between birds and non-flying mammals. Some methodological considerations are given to improve the bridge between the meta-analysis and the comparative method.

  6. A meta-analysis of development aid allocation:  The effects of income level and population size

    DEFF Research Database (Denmark)

    Paldam, Martin

    The effect on aid allocation of the income level and population size in the recipient country is  analyzed. The data show that both variables have a significant and robust negative effect, but  they explain only a small part of the variation. The main thrust of the paper is a meta-analysis of the......The effect on aid allocation of the income level and population size in the recipient country is  analyzed. The data show that both variables have a significant and robust negative effect, but  they explain only a small part of the variation. The main thrust of the paper is a meta...

  7. Estimating required information size by quantifying diversity in random-effects model meta-analyses

    DEFF Research Database (Denmark)

    Wetterslev, Jørn; Thorlund, Kristian; Brok, Jesper

    2009-01-01

    an intervention effect suggested by trials with low-risk of bias. METHODS: Information size calculations need to consider the total model variance in a meta-analysis to control type I and type II errors. Here, we derive an adjusting factor for the required information size under any random-effects model meta......-analysis. RESULTS: We devise a measure of diversity (D2) in a meta-analysis, which is the relative variance reduction when the meta-analysis model is changed from a random-effects into a fixed-effect model. D2 is the percentage that the between-trial variability constitutes of the sum of the between...... and interpreted using several simulations and clinical examples. In addition we show mathematically that diversity is equal to or greater than inconsistency, that is D2 >or= I2, for all meta-analyses. CONCLUSION: We conclude that D2 seems a better alternative than I2 to consider model variation in any random...

  8. Trial sequential analysis reveals insufficient information size and potentially false positive results in many meta-analyses

    DEFF Research Database (Denmark)

    Brok, J.; Thorlund, K.; Gluud, C.

    2008-01-01

    in 80% (insufficient information size). TSA(15%) and TSA(LBHIS) found that 95% and 91% had absence of evidence. The remaining nonsignificant meta-analyses had evidence of lack of effect. CONCLUSION: TSA reveals insufficient information size and potentially false positive results in many meta......OBJECTIVES: To evaluate meta-analyses with trial sequential analysis (TSA). TSA adjusts for random error risk and provides the required number of participants (information size) in a meta-analysis. Meta-analyses not reaching information size are analyzed with trial sequential monitoring boundaries...... analogous to interim monitoring boundaries in a single trial. STUDY DESIGN AND SETTING: We applied TSA on meta-analyses performed in Cochrane Neonatal reviews. We calculated information sizes and monitoring boundaries with three different anticipated intervention effects of 30% relative risk reduction (TSA...

  9. Meta-STEPP: subpopulation treatment effect pattern plot for individual patient data meta-analysis.

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    Wang, Xin Victoria; Cole, Bernard; Bonetti, Marco; Gelber, Richard D

    2016-09-20

    We have developed a method, called Meta-STEPP (subpopulation treatment effect pattern plot for meta-analysis), to explore treatment effect heterogeneity across covariate values in the meta-analysis setting for time-to-event data when the covariate of interest is continuous. Meta-STEPP forms overlapping subpopulations from individual patient data containing similar numbers of events with increasing covariate values, estimates subpopulation treatment effects using standard fixed-effects meta-analysis methodology, displays the estimated subpopulation treatment effect as a function of the covariate values, and provides a statistical test to detect possibly complex treatment-covariate interactions. Simulation studies show that this test has adequate type-I error rate recovery as well as power when reasonable window sizes are chosen. When applied to eight breast cancer trials, Meta-STEPP suggests that chemotherapy is less effective for tumors with high estrogen receptor expression compared with those with low expression. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  10. A Meta-Analysis on Unconscious Thought Effects

    NARCIS (Netherlands)

    Strick, M.A.; Dijksterhuis, A.J.; Bos, M.W.; Sjoerdsma, A.; Baaren, R.B. van; Nordgren, L.F.

    2011-01-01

    A meta-analysis was performed on the unconscious thought effect (UTE). All available published and unpublished data on unconscious thought were included. Our aims were to provide a statistically robust estimate of the effect size of the UTE, to identify significant moderators, and to

  11. Introducing Meta-Partition, a Useful Methodology to Explore Factors That Influence Ecological Effect Sizes.

    Directory of Open Access Journals (Sweden)

    Zaida Ortega

    Full Text Available The study of the heterogeneity of effect sizes is a key aspect of ecological meta-analyses. Here we propose a meta-analytic methodology to study the influence of moderators in effect sizes by splitting heterogeneity: meta-partition. To introduce this methodology, we performed a meta-partition of published data about the traits that influence species sensitivity to habitat loss, that have been previously analyzed through meta-regression. Thus, here we aim to introduce meta-partition and to make an initial comparison with meta-regression. Meta-partition algorithm consists of three steps. Step 1 is to study the heterogeneity of effect sizes under the assumption of fixed effect model. If heterogeneity is found, we perform step 2, that is, to partition the heterogeneity by the moderator that minimizes heterogeneity within a subset while maximizing heterogeneity between subsets. Then, if effect sizes of the subset are still heterogeneous, we repeat step 1 and 2 until we reach final subsets. Finally, step 3 is to integrate effect sizes of final subsets, with fixed effect model if there is homogeneity, and with random effects model if there is heterogeneity. Results show that meta-partition is valuable to assess the importance of moderators in explaining heterogeneity of effect sizes, as well as to assess the directions of these relations and to detect possible interactions between moderators. With meta-partition we have been able to evaluate the importance of moderators in a more objective way than with meta-regression, and to visualize the complex relations that may exist between them. As ecological issues are often influenced by several factors interacting in complex ways, ranking the importance of possible moderators and detecting possible interactions would make meta-partition a useful exploration tool for ecological meta-analyses.

  12. Meta-Analysis of Comparing Personal and Environmental Factors Effective in Addiction Relapse (Iran, 2004 -2012

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    s Safari

    2014-12-01

    Full Text Available Objective: This As a meta-analysis, this study aimed to integrate different studies and investigate the impact of individual and environmental factors on the reappearance of addiction in quitted people. Method: This study is a meta-analysis which uses Hunter and Schmidt approach. For this purpose, 28 out of 42 studies enjoying acceptable methodologies were selected, upon which the meta-analysis was conducted. A meta-analysis checklist was the research instrument. Using summary of the study results, the researcher manually calculated effect size and interpreted it based on the meta-analysis approach and Cohen’s table. Findings: Results revealed that the effect size of environmental factors on addiction relapse was 0.64 while it was obtained 0.41 for individual factors on addiction relapse. Conclusion: According to Cohen’s table, the effect sizes are evaluated as moderate and high for individual factors and environmental factors on addiction relapse, respectively.

  13. Trial Sequential Analysis in systematic reviews with meta-analysis

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    Jørn Wetterslev

    2017-03-01

    Full Text Available Abstract Background Most meta-analyses in systematic reviews, including Cochrane ones, do not have sufficient statistical power to detect or refute even large intervention effects. This is why a meta-analysis ought to be regarded as an interim analysis on its way towards a required information size. The results of the meta-analyses should relate the total number of randomised participants to the estimated required meta-analytic information size accounting for statistical diversity. When the number of participants and the corresponding number of trials in a meta-analysis are insufficient, the use of the traditional 95% confidence interval or the 5% statistical significance threshold will lead to too many false positive conclusions (type I errors and too many false negative conclusions (type II errors. Methods We developed a methodology for interpreting meta-analysis results, using generally accepted, valid evidence on how to adjust thresholds for significance in randomised clinical trials when the required sample size has not been reached. Results The Lan-DeMets trial sequential monitoring boundaries in Trial Sequential Analysis offer adjusted confidence intervals and restricted thresholds for statistical significance when the diversity-adjusted required information size and the corresponding number of required trials for the meta-analysis have not been reached. Trial Sequential Analysis provides a frequentistic approach to control both type I and type II errors. We define the required information size and the corresponding number of required trials in a meta-analysis and the diversity (D2 measure of heterogeneity. We explain the reasons for using Trial Sequential Analysis of meta-analysis when the actual information size fails to reach the required information size. We present examples drawn from traditional meta-analyses using unadjusted naïve 95% confidence intervals and 5% thresholds for statistical significance. Spurious conclusions in

  14. Economic effectiveness of disease management programs: a meta-analysis.

    Science.gov (United States)

    Krause, David S

    2005-04-01

    The economic effectiveness of disease management programs, which are designed to improve the clinical and economic outcomes for chronically ill individuals, has been evaluated extensively. A literature search was performed with MEDLINE and other published sources for the period covering January 1995 to September 2003. The search was limited to empirical articles that measured the direct economic outcomes for asthma, diabetes, and heart disease management programs. Of the 360 articles and presentations evaluated, only 67 met the selection criteria for meta-analysis, which included 32,041 subjects. Although some studies contained multiple measurements of direct economic outcomes, only one average effect size per study was included in the meta-analysis. Based on the studies included in the research, a meta-analysis provided a statistically significant answer to the question of whether disease management programs are economically effective. The magnitude of the observed average effect size for equally weighted studies was 0.311 (95% CI = 0.272-0.350). Statistically significant differences of effect sizes by study design, disease type and intensity of disease management program interventions were not found after a moderating variable, disease severity, was taken into consideration. The results suggest that disease management programs are more effective economically with severely ill enrollees and that chronic disease program interventions are most effective when coordinated with the overall level of disease severity. The findings can be generalized, which may assist health care policy makers and practitioners in addressing the issue of providing economically effective care for the growing number of individuals with chronic illness.

  15. A systematic review of the effectiveness of CBT/ERP group therapy of OCD: A meta-analysis

    DEFF Research Database (Denmark)

    Jónsson, Hjalti; Hougaard, Esben; Bennedsen, Birgit

    , as well as reviewers of the literature have focused on within single treatments effect sizes rather between group effect sizes. OBJECTIVES To make a systematic review, and by methods of meta analysis compute a pooled within effect size of studies of group CBT of OCD and compare these to previously.......05 and 1.25 respectively, with an overall combined pooled within effect size across the categories at 1.18. Finally a between effect sizes of the four studies comparing group therapy to waitlist control group was reported at.1.12 CONCLUSION The reported within effect sizes in this meta-analysis (range 1...

  16. Effect of High-Frequency Transcranial Magnetic Stimulation on Craving in Substance Use Disorder: A Meta-Analysis.

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    Maiti, Rituparna; Mishra, Biswa Ranjan; Hota, Debasish

    2017-01-01

    Repetitive transcranial magnetic stimulation (rTMS), a noninvasive, neuromodulatory tool, has been used to reduce craving in different substance use disorders. There are some studies that have reported conflicting and inconclusive results; therefore, this meta-analysis was conducted to evaluate the effect of high-frequency rTMS on craving in substance use disorder and to investigate the reasons behind the inconsistency across the studies. The authors searched clinical trials from MEDLINE, Cochrane databases, and International Clinical Trials Registry Platform. The PRISMA guidelines, as well as recommended meta-analysis practices, were followed in the selection process, analysis, and reporting of the findings. The effect estimate used was the standardized mean difference (Hedge's g), and heterogeneity across the considered studies was explored using subgroup analyses. The quality assessment was done using the Cochrane risk of bias tool, and sensitivity analysis was performed to check the influences on effect size by statistical models. After screening and assessment of eligibility, finally 10 studies were included for meta-analysis, which includes six studies on alcohol and four studies on nicotine use disorder. The random-model analysis revealed a pooled effect size of 0.75 (95% CI=0.29 to 1.21, p=0.001), whereas the fixed-model analysis showed a large effect size of 0.87 (95% CI=0.63 to 1.12, peffect size of -0.06 (95% CI=-0.89 to 0.77, p=0.88). In the case of nicotine use disorder, random-model analysis revealed an effect size of 1.00 (95% CI=0.48 to 1.55, p=0.0001), whereas fixed-model analysis also showed a large effect size of 0.96 (95% CI=0.71 to 1.22). The present meta-analysis identified a beneficial effect of high-frequency rTMS on craving associated with nicotine use disorder but not alcohol use disorder.

  17. An overview of meta-analysis for clinicians

    Science.gov (United States)

    Lee, Young Ho

    2018-01-01

    The number of medical studies being published is increasing exponentially, and clinicians must routinely process large amounts of new information. Moreover, the results of individual studies are often insufficient to provide confident answers, as their results are not consistently reproducible. A meta-analysis is a statistical method for combining the results of different studies on the same topic and it may resolve conflicts among studies. Meta-analysis is being used increasingly and plays an important role in medical research. This review introduces the basic concepts, steps, advantages, and caveats of meta-analysis, to help clinicians understand it in clinical practice and research. A major advantage of a meta-analysis is that it produces a precise estimate of the effect size, with considerably increased statistical power, which is important when the power of the primary study is limited because of a small sample size. A meta-analysis may yield conclusive results when individual studies are inconclusive. Furthermore, meta-analyses investigate the source of variation and different effects among subgroups. In summary, a meta-analysis is an objective, quantitative method that provides less biased estimates on a specific topic. Understanding how to conduct a meta-analysis aids clinicians in the process of making clinical decisions. PMID:29277096

  18. An overview of meta-analysis for clinicians.

    Science.gov (United States)

    Lee, Young Ho

    2018-03-01

    The number of medical studies being published is increasing exponentially, and clinicians must routinely process large amounts of new information. Moreover, the results of individual studies are often insufficient to provide confident answers, as their results are not consistently reproducible. A meta-analysis is a statistical method for combining the results of different studies on the same topic and it may resolve conflicts among studies. Meta-analysis is being used increasingly and plays an important role in medical research. This review introduces the basic concepts, steps, advantages, and caveats of meta-analysis, to help clinicians understand it in clinical practice and research. A major advantage of a meta-analysis is that it produces a precise estimate of the effect size, with considerably increased statistical power, which is important when the power of the primary study is limited because of a small sample size. A meta-analysis may yield conclusive results when individual studies are inconclusive. Furthermore, meta-analyses investigate the source of variation and different effects among subgroups. In summary, a meta-analysis is an objective, quantitative method that provides less biased estimates on a specific topic. Understanding how to conduct a meta-analysis aids clinicians in the process of making clinical decisions.

  19. Hierarchical evaluation of electrical stimulation protocols for chronic wound healing: An effect size meta-analysis.

    Science.gov (United States)

    Khouri, Charles; Kotzki, Sylvain; Roustit, Matthieu; Blaise, Sophie; Gueyffier, Francois; Cracowski, Jean-Luc

    2017-09-01

    Electrical stimulation (ES) has been tested for decades to improve chronic wound healing. However, uncertainty remains on the magnitude of the efficacy and on the best applicable protocol. We conducted an effect size meta-analysis to assess the overall efficacy of ES on wound healing, to compare the efficacy of the different modalities of electrical stimulation, and to determine whether efficacy differs depending on the wound etiology, size, and age of the chronic wound. Twenty-nine randomized clinical trials with 1,510 patients and 1,753 ulcers were selected. Overall efficacy of ES on would healing was a 0.72 SMD (95% CI: 0.48, 1) corresponding to a moderate to large effect size. We found that unidirectional high voltage pulsed current (HVPC) with the active electrode over the wound was the best evidence-based protocol to improve wound healing with a 0.8 SMD (95% CI: 0.38, 1.21), while evaluation of the efficacy of direct current was limited by the small number of studies. ES was more effective on pressure ulcers compared to venous and diabetic ulcers, and efficacy trended to be inversely associated with the wound size and duration. This study confirms the overall efficacy of ES to enhance healing of chronic wounds and highlights the superiority of HVPC over other type of currents, which is more effective on pressure ulcers, and inversely associated with the wound size and duration. This will enable to standardize future ES practices. © 2017 by the Wound Healing Society.

  20. Trial Sequential Analysis in systematic reviews with meta-analysis

    DEFF Research Database (Denmark)

    Wetterslev, Jørn; Jakobsen, Janus Christian; Gluud, Christian

    2017-01-01

    BACKGROUND: Most meta-analyses in systematic reviews, including Cochrane ones, do not have sufficient statistical power to detect or refute even large intervention effects. This is why a meta-analysis ought to be regarded as an interim analysis on its way towards a required information size...... from traditional meta-analyses using unadjusted naïve 95% confidence intervals and 5% thresholds for statistical significance. Spurious conclusions in systematic reviews with traditional meta-analyses can be reduced using Trial Sequential Analysis. Several empirical studies have demonstrated...

  1. Sleep-deprivation effect on human performance: a meta-analysis approach

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    Candice D. Griffith; Candice D. Griffith; Sankaran Mahadevan

    2006-05-01

    Human fatigue is hard to define since there is no direct measure of fatigue, much like stress. Instead fatigue must be inferred from measures that are affected by fatigue. One such measurable output affected by fatigue is reaction time. In this study the relationship of reaction time to sleep deprivation is studied. These variables were selected because reaction time and hours of sleep deprivation are straightforward characteristics of fatigue to begin the investigation of fatigue effects on performance. Meta-analysis, a widely used procedure in medical and psychological studies, is applied to the variety of fatigue literature collected from various fields in this study. Meta-analysis establishes a procedure for coding and analyzing information from various studies to compute an effect size. In this research the effect size reported is the difference between standardized means, and is found to be -0.6341, implying a strong relationship between sleep deprivation and performance degradation.

  2. Interpreting meta-analysis according to the adequacy of sample size. An example using isoniazid chemoprophylaxis for tuberculosis in purified protein derivative negative HIV-infected individuals

    Directory of Open Access Journals (Sweden)

    Kristian Thorlund

    2010-04-01

    Full Text Available Kristian Thorlund1,2, Aranka Anema3, Edward Mills41Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada; 2The Copenhagen Trial Unit, Centre for Clinical Intervention Research, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; 3British Columbia Centre for Excellence in HIV/AIDS, University of British Columbia, Vancouver, British Columbia, Canada; 4Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, CanadaObjective: To illustrate the utility of statistical monitoring boundaries in meta-analysis, and provide a framework in which meta-analysis can be interpreted according to the adequacy of sample size. To propose a simple method for determining how many patients need to be randomized in a future trial before a meta-analysis can be deemed conclusive.Study design and setting: Prospective meta-analysis of randomized clinical trials (RCTs that evaluated the effectiveness of isoniazid chemoprophylaxis versus placebo for preventing the incidence of tuberculosis disease among human immunodeficiency virus (HIV-positive individuals testing purified protein derivative negative. Assessment of meta-analysis precision using trial sequential analysis (TSA with LanDeMets monitoring boundaries. Sample size determination for a future trials to make the meta-analysis conclusive according to the thresholds set by the monitoring boundaries.Results: The meta-analysis included nine trials comprising 2,911 trial participants and yielded a relative risk of 0.74 (95% CI, 0.53–1.04, P = 0.082, I2 = 0%. To deem the meta-analysis conclusive according to the thresholds set by the monitoring boundaries, a future RCT would need to randomize 3,800 participants.Conclusion: Statistical monitoring boundaries provide a framework for interpreting meta-analysis according to the adequacy of sample size and project the required sample size for a future RCT to make a meta-analysis conclusive

  3. Trial Sequential Methods for Meta-Analysis

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    Kulinskaya, Elena; Wood, John

    2014-01-01

    Statistical methods for sequential meta-analysis have applications also for the design of new trials. Existing methods are based on group sequential methods developed for single trials and start with the calculation of a required information size. This works satisfactorily within the framework of fixed effects meta-analysis, but conceptual…

  4. Effect of Desflurane versus Sevoflurane in Pediatric Anesthesia: A Meta-Analysis.

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    He, Jiaxuan; Zhang, Yong; Xue, Rongliang; Lv, Jianrui; Ding, Xiaoying; Zhang, Zhenni

    2015-01-01

    To compare the effect of desflurane versus sevoflurane in pediatric anesthesia by conducting meta-analysis. Studies were searched from PubMed, Medline, Springer, Elsevier Science Direct, Cochrane Library and Google Scholar up to July 2014. Weighted mean difference (WMD) or risk ratio (RR) and 95% confidence intervals (CIs) were considered as effect sizes. Heterogeneity across studies was assessed by Cochran Q test and I2 statistic. The random effects model was performed in the meta-analysis when heterogeneity was observed, or the fixed effect model was used. Review Manager 5.1 software was applied for the meta-analysis. A total of 11 studies (13 comparisons) involving 1,273 objects were included in this meta-analysis. No heterogeneity was observed between studies for any comparison but for postoperative extubation time. The results showed significant differences between desflurane and sevoflurane groups for postoperative extubation time (WMD = -3.87, 95%CI = -6.14 to -1.60, P 0.05) were detected for discharge from the recovery room, oculocardiac reflex, nausea and vomiting and severe pain. Desflurane may have less adverse effects than sevoflurane when used in pediatric anesthesia with significantly shorter postoperative extubation time, eye opening time and awakening time as well as slighter agitation.

  5. Living network meta-analysis compared with pairwise meta-analysis in comparative effectiveness research: empirical study

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    Nikolakopoulou, Adriani; Mavridis, Dimitris; Furukawa, Toshi A; Cipriani, Andrea; Tricco, Andrea C; Straus, Sharon E; Siontis, George C M; Egger, Matthias

    2018-01-01

    Abstract Objective To examine whether the continuous updating of networks of prospectively planned randomised controlled trials (RCTs) (“living” network meta-analysis) provides strong evidence against the null hypothesis in comparative effectiveness of medical interventions earlier than the updating of conventional, pairwise meta-analysis. Design Empirical study of the accumulating evidence about the comparative effectiveness of clinical interventions. Data sources Database of network meta-analyses of RCTs identified through searches of Medline, Embase, and the Cochrane Database of Systematic Reviews until 14 April 2015. Eligibility criteria for study selection Network meta-analyses published after January 2012 that compared at least five treatments and included at least 20 RCTs. Clinical experts were asked to identify in each network the treatment comparison of greatest clinical interest. Comparisons were excluded for which direct and indirect evidence disagreed, based on side, or node, splitting test (Pmeta-analysis. The frequency and time to strong evidence was compared against the null hypothesis between pairwise and network meta-analyses. Results 49 comparisons of interest from 44 networks were included; most (n=39, 80%) were between active drugs, mainly from the specialties of cardiology, endocrinology, psychiatry, and rheumatology. 29 comparisons were informed by both direct and indirect evidence (59%), 13 by indirect evidence (27%), and 7 by direct evidence (14%). Both network and pairwise meta-analysis provided strong evidence against the null hypothesis for seven comparisons, but for an additional 10 comparisons only network meta-analysis provided strong evidence against the null hypothesis (P=0.002). The median time to strong evidence against the null hypothesis was 19 years with living network meta-analysis and 23 years with living pairwise meta-analysis (hazard ratio 2.78, 95% confidence interval 1.00 to 7.72, P=0.05). Studies directly comparing

  6. Size matters: a meta-analysis on the impact of hospital size on patient mortality.

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    Fareed, Naleef

    2012-06-01

    This paper seeks to understand the relationship between hospital size and patient mortality. Patient mortality has been used by several studies in the health services research field as a proxy for measuring healthcare quality. A systematic review is conducted to identify studies that investigate the impact of hospital size on patient mortality. Using the findings of 21 effect sizes from 10 eligible studies, a meta-analysis is performed using a random effects model. Subgroup analyses using three factors--the measure used for hospital size, type of mortality measure used and whether mortality was adjusted or unadjusted--were utilised to investigate their moderating influence on the study's primary relationship. Results from this analysis indicate that big hospitals have lower odds of patient mortality versus small hospitals. Specifically, the probability of patient mortality in a big hospital, in reference to a small hospital, is 11% less. Subgroup analyses show that studies with unadjusted mortality rates have an even lower overall odds ratio of mortality versus studies with adjusted mortality rates. Aside from some limitations in data reporting, the findings of this paper support theoretical notions that big hospitals have lower mortality rates than small hospitals. Guidelines for better data reporting and future research are provided to further explore the phenomenon. Policy implications of this paper's findings are underscored and a sense of urgency is called for in an effort to help improve the state of a healthcare system that struggles with advancing healthcare quality. © 2012 The Author. International Journal of Evidence-Based Healthcare © 2012 The Joanna Briggs Institute.

  7. The Flynn Effect: A Meta-analysis

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    Trahan, Lisa; Stuebing, Karla K.; Hiscock, Merril K.; Fletcher, Jack M.

    2014-01-01

    The “Flynn effect” refers to the observed rise in IQ scores over time, resulting in norms obsolescence. Although the Flynn effect is widely accepted, most approaches to estimating it have relied upon “scorecard” approaches that make estimates of its magnitude and error of measurement controversial and prevent determination of factors that moderate the Flynn effect across different IQ tests. We conducted a meta-analysis to determine the magnitude of the Flynn effect with a higher degree of precision, to determine the error of measurement, and to assess the impact of several moderator variables on the mean effect size. Across 285 studies (N = 14,031) since 1951 with administrations of two intelligence tests with different normative bases, the meta-analytic mean was 2.31, 95% CI [1.99, 2.64], standard score points per decade. The mean effect size for 53 comparisons (N = 3,951) (excluding three atypical studies that inflate the estimates) involving modern (since 1972) Stanford-Binet and Wechsler IQ tests (2.93, 95% CI [2.3, 3.5], IQ points per decade) was comparable to previous estimates of about 3 points per decade, but not consistent with the hypothesis that the Flynn effect is diminishing. For modern tests, study sample (larger increases for validation research samples vs. test standardization samples) and order of administration explained unique variance in the Flynn effect, but age and ability level were not significant moderators. These results supported previous estimates of the Flynn effect and its robustness across different age groups, measures, samples, and levels of performance. PMID:24979188

  8. Introduction, comparison, and validation of Meta-Essentials: A free and simple tool for meta-analysis.

    Science.gov (United States)

    Suurmond, Robert; van Rhee, Henk; Hak, Tony

    2017-12-01

    We present a new tool for meta-analysis, Meta-Essentials, which is free of charge and easy to use. In this paper, we introduce the tool and compare its features to other tools for meta-analysis. We also provide detailed information on the validation of the tool. Although free of charge and simple, Meta-Essentials automatically calculates effect sizes from a wide range of statistics and can be used for a wide range of meta-analysis applications, including subgroup analysis, moderator analysis, and publication bias analyses. The confidence interval of the overall effect is automatically based on the Knapp-Hartung adjustment of the DerSimonian-Laird estimator. However, more advanced meta-analysis methods such as meta-analytical structural equation modelling and meta-regression with multiple covariates are not available. In summary, Meta-Essentials may prove a valuable resource for meta-analysts, including researchers, teachers, and students. © 2017 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd.

  9. Retest effects in working memory capacity tests: A meta-analysis.

    Science.gov (United States)

    Scharfen, Jana; Jansen, Katrin; Holling, Heinz

    2018-06-15

    The repeated administration of working memory capacity tests is common in clinical and research settings. For cognitive ability tests and different neuropsychological tests, meta-analyses have shown that they are prone to retest effects, which have to be accounted for when interpreting retest scores. Using a multilevel approach, this meta-analysis aims at showing the reproducibility of retest effects in working memory capacity tests for up to seven test administrations, and examines the impact of the length of the test-retest interval, test modality, equivalence of test forms and participant age on the size of retest effects. Furthermore, it is assessed whether the size of retest effects depends on the test paradigm. An extensive literature search revealed 234 effect sizes from 95 samples and 68 studies, in which healthy participants between 12 and 70 years repeatedly performed a working memory capacity test. Results yield a weighted average of g = 0.28 for retest effects from the first to the second test administration, and a significant increase in effect sizes was observed up to the fourth test administration. The length of the test-retest interval and publication year were found to moderate the size of retest effects. Retest effects differed between the paradigms of working memory capacity tests. These findings call for the development and use of appropriate experimental or statistical methods to address retest effects in working memory capacity tests.

  10. Living network meta-analysis compared with pairwise meta-analysis in comparative effectiveness research: empirical study.

    Science.gov (United States)

    Nikolakopoulou, Adriani; Mavridis, Dimitris; Furukawa, Toshi A; Cipriani, Andrea; Tricco, Andrea C; Straus, Sharon E; Siontis, George C M; Egger, Matthias; Salanti, Georgia

    2018-02-28

    To examine whether the continuous updating of networks of prospectively planned randomised controlled trials (RCTs) ("living" network meta-analysis) provides strong evidence against the null hypothesis in comparative effectiveness of medical interventions earlier than the updating of conventional, pairwise meta-analysis. Empirical study of the accumulating evidence about the comparative effectiveness of clinical interventions. Database of network meta-analyses of RCTs identified through searches of Medline, Embase, and the Cochrane Database of Systematic Reviews until 14 April 2015. Network meta-analyses published after January 2012 that compared at least five treatments and included at least 20 RCTs. Clinical experts were asked to identify in each network the treatment comparison of greatest clinical interest. Comparisons were excluded for which direct and indirect evidence disagreed, based on side, or node, splitting test (Pmeta-analyses were performed for each selected comparison. Monitoring boundaries of statistical significance were constructed and the evidence against the null hypothesis was considered to be strong when the monitoring boundaries were crossed. A significance level was defined as α=5%, power of 90% (β=10%), and an anticipated treatment effect to detect equal to the final estimate from the network meta-analysis. The frequency and time to strong evidence was compared against the null hypothesis between pairwise and network meta-analyses. 49 comparisons of interest from 44 networks were included; most (n=39, 80%) were between active drugs, mainly from the specialties of cardiology, endocrinology, psychiatry, and rheumatology. 29 comparisons were informed by both direct and indirect evidence (59%), 13 by indirect evidence (27%), and 7 by direct evidence (14%). Both network and pairwise meta-analysis provided strong evidence against the null hypothesis for seven comparisons, but for an additional 10 comparisons only network meta-analysis provided

  11. Small studies are more heterogeneous than large ones: a meta-meta-analysis

    NARCIS (Netherlands)

    Hout, J. in't; Ioannidis, J.P.; Borm, G.F.; Goeman, J.J.

    2015-01-01

    OBJECTIVES: Between-study heterogeneity plays an important role in random-effects models for meta-analysis. Most clinical trials are small, and small trials are often associated with larger effect sizes. We empirically evaluated whether there is also a relationship between trial size and

  12. A Bayesian Nonparametric Meta-Analysis Model

    Science.gov (United States)

    Karabatsos, George; Talbott, Elizabeth; Walker, Stephen G.

    2015-01-01

    In a meta-analysis, it is important to specify a model that adequately describes the effect-size distribution of the underlying population of studies. The conventional normal fixed-effect and normal random-effects models assume a normal effect-size population distribution, conditionally on parameters and covariates. For estimating the mean overall…

  13. The evaluation of meta-analysis techniques for quantifying prescribed fire effects on fuel loadings.

    Science.gov (United States)

    Karen E. Kopper; Donald McKenzie; David L. Peterson

    2009-01-01

    Models and effect-size metrics for meta-analysis were compared in four separate meta-analyses quantifying surface fuels after prescribed fires in ponderosa pine (Pinus ponderosa Dougl. ex Laws.) forests of the Western United States. An aggregated data set was compiled from eight published reports that contained data from 65 fire treatment units....

  14. Effect of Exergames on Depression: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Li, Jinhui; Theng, Yin-Leng; Foo, Schubert

    2016-01-01

    Depression is a major public health concern in current society. In recent years many studies began to investigate the potential benefits of exergames on depression. The current study aimed to provide a systematic review to synthesize the existing studies and discover the overall effect size of exergames on treating depression. A comprehensive literature search was conducted among major bibliographic databases in computer technology, psychology, and medical science. Key study characteristics of participants, interventions, and experiment were extracted in the systematic review. Both studies using independent groups and matched groups were included in meta-analysis. Overall effect size of Hedges' g was calculated, followed by subgroup analyses. Nine studies included in the review, while eight studies applying exergames of Nintendo's Wii or Wii Fit. A random effects meta-analysis on eight studies resulted an overall significant effect size of g = 0.21. Demographic factors, depression severity, number of session, and game type were found to be significant moderators for the effectiveness. The study has not only supported the positive effect of exergames on alleviating depression, but also provided many theoretical and practical implications for health professionals and police makers. More rigorous experimental controlled studies are needed in this new research field.

  15. Meta-analysis and systematic review of studies on the effectiveness of HIV stigma reduction programs.

    Science.gov (United States)

    Mak, Winnie W S; Mo, Phoenix K H; Ma, Gloria Y K; Lam, Maggie Y Y

    2017-09-01

    The present study conducted a meta-analysis and systematic review on studies evaluating the effectiveness of stigma reduction programs in improving knowledge and reducing negative attitudes towards people living with HIV (PLHIV). Meta-analysis (k = 42 studies) found significant and small effect sizes in the improvement of the participants' knowledge of HIV/AIDS from interventions with (Cohen's d = 0.48, 95% CI [0.30, 0.66]) and without control groups (Cohen's d = 0.42, 95% CI [0.28, 0.57]). Significant and small effect sizes were found in the improvement of the participants' attitudes toward PLHIV from interventions with (Cohen's d = 0.39, 95% CI [0.23, 0.55]) and without control groups (Cohen's d = 0.25, 95% CI [0.11, 0.39]). Significant and small effect sizes were sustained at the follow-up assessments. Subgroup analysis showed that number of intervention sessions, intervention settings, and sample type significantly moderated the effect sizes in the meta-analysis. Findings from the systematic review of 35 studies indicated that most of the included studies showed positive results in reducing negative attitudes toward PLHIV and improving HIV-related knowledge. Most of the included studies tended to have low methodological quality. The present meta-analysis and systematic review indicated that the studies generally found small improvement in HIV-related knowledge and reduction in negative attitudes towards PLHIV among the stigma reduction programs being evaluated. High-quality stigma reduction programs with multidimensional stigma indicators and psychometrically sound outcome measures are highly warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. The Effect of Hypnosis on Anxiety in Patients With Cancer: A Meta-Analysis.

    Science.gov (United States)

    Chen, Pei-Ying; Liu, Ying-Mei; Chen, Mei-Ling

    2017-06-01

    Anxiety is a common form of psychological distress in patients with cancer. One recognized nonpharmacological intervention to reduce anxiety for various populations is hypnotherapy or hypnosis. However, its effect in reducing anxiety in cancer patients has not been systematically evaluated. This meta-analysis was designed to synthesize the immediate and sustained effects of hypnosis on anxiety of cancer patients and to identify moderators for these hypnosis effects. Qualified studies including randomized controlled trials (RCT) and pre-post design studies were identified by searching seven electronic databases: Scopus, Medline Ovidsp, PubMed, PsycInfo-Ovid, Academic Search Premier, CINAHL Plus with FT-EBSCO, and SDOL. Effect size (Hedges' g) was computed for each study. Random-effect modeling was used to combine effect sizes across studies. All statistical analyses were conducted with Comprehensive Meta-Analysis, version 2 (Biostat, Inc., Englewood, NJ, USA). Our meta-analysis of 20 studies found that hypnosis had a significant immediate effect on anxiety in cancer patients (Hedges' g: 0.70-1.41, p Hypnosis delivered by a therapist was significantly more effective than self-hypnosis. Hypnosis can reduce anxiety of cancer patients, especially for pediatric cancer patients who experience procedure-related stress. We recommend therapist-delivered hypnosis should be preferred until more effective self-hypnosis strategies are developed. © 2017 Sigma Theta Tau International.

  17. Egg size and offspring quality: a meta-analysis in birds.

    Science.gov (United States)

    Krist, Miloš

    2011-08-01

    Parents affect offspring fitness by propagule size and quality, selection of oviposition site, quality of incubation, feeding of dependent young, and their defence against predators and parasites. Despite many case studies on each of these topics, this knowledge has not been rigorously integrated into individual parental care traits for any taxon. Consequently, we lack a comprehensive, quantitative assessment of how parental care modifies offspring phenotypes. This meta-analysis of 283 studies with 1805 correlations between egg size and offspring quality in birds is intended to fill this gap. The large sample size enabled testing of how the magnitude of the relationship between egg size and offspring quality depends on a number of variables. Egg size was positively related to nearly all studied offspring traits across all stages of the offspring life cycle. Not surprisingly, the relationship was strongest at hatching but persisted until the post-fledging stage. Morphological traits were the most closely related to egg size but significant relationships were also found with hatching success, chick survival, and growth rate. Non-significant effect sizes were found for egg fertility, chick immunity, behaviour, and life-history or sexual traits. Effect size did not depend on whether chicks were raised by their natural parents or were cross-fostered to other territories. Effect size did not depend on species-specific traits such as developmental mode, clutch size, and relative size of the egg, but was larger if tested in captive compared to wild populations and between rather than within broods. In sum, published studies support the view that egg size affects juvenile survival. There are very few studies that tested the relationship between egg size and the fecundity component of offspring fitness, and no studies on offspring survival as adults or on global fitness. More data are also needed for the relationships between egg size and offspring behavioural and

  18. Effects of stimulants and atomoxetine on emotional lability in adults: A systematic review and meta-analysis.

    Science.gov (United States)

    Moukhtarian, T R; Cooper, R E; Vassos, E; Moran, P; Asherson, P

    2017-07-01

    Emotional lability (EL) is an associated feature of attention-deficit/hyperactivity disorder (ADHD) in adults, contributing to functional impairment. Yet the effect of pharmacological treatments for ADHD on EL symptoms is unknown. We conducted a systematic review and meta-analysis to examine the effects of stimulants and atomoxetine on symptoms of EL and compare these with the effects on core ADHD symptoms. A systematic search was conducted on the databases Embase, PsychInfo, and Ovid Medline ® and the clinicaltrials.gov website. We included randomised, double-blind, placebo-controlled trials of stimulants and atomoxetine in adults aged 18-60 years, with any mental health diagnosis characterised by emotional or mood instability, with at least one outcome measure of EL. All identified trials were on adults with ADHD. A random-effects meta-analysis with standardised mean difference and 95% confidence intervals was used to investigate the effect size on EL and compare this to the effect on core ADHD symptoms. Of the 3,864 publications identified, nine trials met the inclusion criteria for the meta-analysis. Stimulants and atomoxetine led to large mean weighted effect-sizes for on ADHD symptoms (n=9, SMD=-0.8, 95% CI:-1.07 to -0.53). EL outcomes showed more moderate but definite effects (n=9, SMD=-0.41, 95% CI:-0.57 to -0.25). In this meta-analysis, stimulants and atomoxetine were moderately effective for EL symptoms, while effect size on core ADHD symptoms was twice as large. Methodological issues may partially explain the difference in effect size. Reduced average effect size could also reflect heterogeneity of EL with ADHD pharmacotherapy responsive and non-responsive sub-types. Our findings indicate that EL may be less responsive than ADHD symptoms overall, perhaps indicating the need for adjunctive psychotherapy in some cases. To clarify these questions, our findings need replication in studies selecting subjects for high EL and targeting EL as the primary

  19. Determinants of investment behaviour. Methods and applications of meta-analysis

    International Nuclear Information System (INIS)

    Koetse, M.J.

    2006-01-01

    Meta-analysis is gradually gaining ground in economics as a research method to objectively and quantitatively summarise a body of existing empirical evidence. This dissertation studies the performance of well-known meta-analytic models and presents two meta-analysis applications. Despite its many attractive features, meta-analysis faces several methodical difficulties, especially when applied in economic research. We investigate two specific methodical problems that any meta-analysis in economics will have to deal with, viz., systematic effect-size variation due to primary-study misspecifications, and random effect-size heterogeneity. Using Monte-Carlo analysis we investigate the effects of these methodical problems on the results of a meta-analysis, and study the small-sample properties of several well-known and often applied meta-estimators. The focus of the meta-analysis applications is on two topics that are relevant for understanding investment behaviour, viz., the impact of uncertainty on investment spending, and the potential for substitution of capital for energy in production processes. In the first application we aim to shed light on the direction of the relationship between investment and uncertainty, and to uncover which factors are empirically relevant for explaining the wide variety in study outcomes. In the second application our goal is to analyse the direction and magnitude of capital-energy substitution potential, and to analyse the empirical relevance of suggested sources of variation in elasticity estimates

  20. Determinants of investment behaviour. Methods and applications of meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Koetse, M.J.

    2006-03-14

    Meta-analysis is gradually gaining ground in economics as a research method to objectively and quantitatively summarise a body of existing empirical evidence. This dissertation studies the performance of well-known meta-analytic models and presents two meta-analysis applications. Despite its many attractive features, meta-analysis faces several methodical difficulties, especially when applied in economic research. We investigate two specific methodical problems that any meta-analysis in economics will have to deal with, viz., systematic effect-size variation due to primary-study misspecifications, and random effect-size heterogeneity. Using Monte-Carlo analysis we investigate the effects of these methodical problems on the results of a meta-analysis, and study the small-sample properties of several well-known and often applied meta-estimators. The focus of the meta-analysis applications is on two topics that are relevant for understanding investment behaviour, viz., the impact of uncertainty on investment spending, and the potential for substitution of capital for energy in production processes. In the first application we aim to shed light on the direction of the relationship between investment and uncertainty, and to uncover which factors are empirically relevant for explaining the wide variety in study outcomes. In the second application our goal is to analyse the direction and magnitude of capital-energy substitution potential, and to analyse the empirical relevance of suggested sources of variation in elasticity estimates.

  1. The Influence of Function, Topography, and Setting on Noncontingent Reinforcement Effect Sizes for Reduction in Problem Behavior: A Meta-Analysis of Single-Case Experimental Design Data

    Science.gov (United States)

    Ritter, William A.; Barnard-Brak, Lucy; Richman, David M.; Grubb, Laura M.

    2018-01-01

    Richman et al. ("J Appl Behav Anal" 48:131-152, 2015) completed a meta-analytic analysis of single-case experimental design data on noncontingent reinforcement (NCR) for the treatment of problem behavior exhibited by individuals with developmental disabilities. Results showed that (1) NCR produced very large effect sizes for reduction in…

  2. Comparing Active Pediatric Obesity Treatments Using Meta-Analysis

    Science.gov (United States)

    Gilles, Allyson; Cassano, Michael; Shepherd, Elizabeth J.; Higgins, Diana; Hecker, Jeffrey E.; Nangle, Douglas W.

    2008-01-01

    The current meta-analysis reviews research on the treatment of pediatric obesity focusing on studies that have been published since 1994. Eleven studies (22 comparisons, 115 effect sizes, N = 447) were included in the present meta-analysis. Results indicated that comprehensive behavioral interventions may be improved in at least two ways:…

  3. Effectiveness of various innovative learning methods in health science classrooms: a meta-analysis.

    Science.gov (United States)

    Kalaian, Sema A; Kasim, Rafa M

    2017-12-01

    This study reports the results of a meta-analysis of the available literature on the effectiveness of various forms of innovative small-group learning methods on student achievement in undergraduate college health science classrooms. The results of the analysis revealed that most of the primary studies supported the effectiveness of the small-group learning methods in improving students' academic achievement with an overall weighted average effect-size of 0.59 in standard deviation units favoring small-group learning methods. The subgroup analysis showed that the various forms of innovative and reform-based small-group learning interventions appeared to be significantly more effective for students in higher levels of college classes (sophomore, junior, and senior levels), students in other countries (non-U.S.) worldwide, students in groups of four or less, and students who choose their own group. The random-effects meta-regression results revealed that the effect sizes were influenced significantly by the instructional duration of the primary studies. This means that studies with longer hours of instruction yielded higher effect sizes and on average every 1 h increase in instruction, the predicted increase in effect size was 0.009 standard deviation units, which is considered as a small effect. These results may help health science and nursing educators by providing guidance in identifying the conditions under which various forms of innovative small-group learning pedagogies are collectively more effective than the traditional lecture-based teaching instruction.

  4. Meta-analysis of the relationship between psychosocial indexes with mental health

    Directory of Open Access Journals (Sweden)

    Ayaub Faizy

    2015-09-01

    Full Text Available Background: The expansion of studies that done in the demand of effective factors such as social factors on mental health provides the ground work for the combination of these studies. So, this meta-analysis was implemented to determine the summary effect size of the relationship between social indexes and mental health measures Material and Methods: The method used in this study is a Meta-Analysis. To achieve above aim used of quantitative findings from 46 studies, that computed 77 effect sizes from these. The studies that were used in this study collected from databases such as magiran, noormags, Scientific Information Database and proceeding articles that published in the Seminars of college student’s Mental Health. After reviewing the inclusion and exclusion criteria, the correlation effect sizes in selected studies were analyzed with the CMA2 software. In this study, were calculated both random and fixed models, that selected random model, according to the results of the heterogeneity analysis of the Q and I2 factors. Results: The results showed that the combinational effect size of the studies obtained 0.139, after eliminated 10 effect sizes. The combined effect size of studies was calculated low based on Cohen's criteria. Also, the results of heterogeneity analysis indicated that there are moderating variables in the studies. The evidence of this meta-analysis associated with prior theoretical and empirical foundations, indicates the relationship between social support and mental health. Conclusion: According to the results of this meta-analysis for successful mental health programs due to cultural and social issues will be necessary.

  5. Meta-analysis of surgical safety checklist effects on teamwork, communication, morbidity, mortality, and safety.

    Science.gov (United States)

    Lyons, Vanessa E; Popejoy, Lori L

    2014-02-01

    The purpose of this study is to examine the effectiveness of surgical safety checklists on teamwork, communication, morbidity, mortality, and compliance with safety measures through meta-analysis. Four meta-analyses were conducted on 19 studies that met the inclusion criteria. The effect size of checklists on teamwork and communication was 1.180 (p = .003), on morbidity and mortality was 0.123 (p = .003) and 0.088 (p = .001), respectively, and on compliance with safety measures was 0.268 (p teamwork and communication, reduce morbidity and mortality, and improve compliance with safety measures. This meta-analysis is limited in its generalizability based on the limited number of studies and the inclusion of only published research. Future research is needed to examine possible moderating variables for the effects of surgical safety checklists.

  6. Moral development and recidivism: a meta-analysis

    NARCIS (Netherlands)

    van Vugt, E.; Gibbs, J.; Stams, G.J.; Bijleveld, C.; Hendriks, J.; van der Laan, P.

    2011-01-01

    A meta-analysis of 19 studies (N = 15,992 offenders) showed a significant inverse relation between more mature moral development and recidivism. Moderator analyses revealed a larger effect size for moral cognition (r = .20) than for moral emotion (r = .11). Effect sizes for production measures (r =

  7. Effects of chlorhexidine varnish on caries during orthodontic treatment: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Elaine Machado Pingueiro OKADA

    Full Text Available Abstract This study aimed to perform a systematic review and meta-analysis to evaluate the effectiveness of chlorhexidine varnish on the reduction of caries incidence during fixed orthodontic treatment. The literature searches involved The Cochrane Library, Medline, Scopus, OpenSigle databases and manual searches. The search on OpenSigle did not produce any additional articles. Clinical studies conducted in patients with orthodontic fixed appliances that used professional application of chlorhexidine varnish were included. The effect-size was calculated and a meta-analysis was performed. From 182 abstracts, a total of six articles fulfilled the inclusion criteria. After reading the full articles, one was excluded because of lack of a control group. Three articles were used for continuous data analysis, and two articles were used for the dichotomous data analysis. The pooled meta-analysis with continuous data demonstrated chlorhexidine varnish effectiveness on caries reduction (p = 0.003, with a mean difference and confidence interval of −1.49 [−2.47, −0.51]. On the basis of the pooled meta-analysis of continuous data, we were able to conclude that professional application of chlorhexidine varnish is effective in caries incidence reduction during fixed orthodontic treatment.

  8. Comparison the effects of poor health and low income on early retirement: a systematic review and meta-analysis.

    Science.gov (United States)

    Homaie Rad, Enayatollah; Rashidian, Arash; Arab, Mohamad; Souri, Ali

    2017-08-08

    The main aim of this study was to estimate the effects of poor health and low income on early retirement. For this purpose systematic review and meta-analysis were conducted. Web of Science, PUBMED and Scopus databases were searched systematically. Finally 17 surveys were added in meta-analysis. These studies were conducted in 13 countries. At the end a Meta regression was done to show the effects of welfare system type on effect sizes of poor health and low income. The results of this study showed that poor health had effect on the risk of early retirement. (Poor health pooled effect sizes: 1.279 CI: (1.15 1.41), low income pooled effect sizes: 1.042 CI: (0.92 1.17), (poor health pooled marginal effects: 0.046 CI: (-0.03 0.12), low income pooled marginal effects: -0.002 CI: (-0.003 0.000). The results of this study showed that association between poor health and early retirement was stronger in comparison with low income and early retirement.

  9. Hypothyroidism and carpal tunnel syndrome: a meta-analysis.

    Science.gov (United States)

    Shiri, Rahman

    2014-12-01

    This study aimed to assess the magnitude of the association between hypothyroidism and carpal tunnel syndrome (CTS). Eighteen studies were included in a random-effects meta-analysis. A meta-analysis of the studies that did not control their estimates for any confounder showed an association between a thyroid disease (hypo- or hyperthyroidism) and CTS (N = 9,573, effect size [ES] = 1.32 (95% confidence interval [CI], 1.04-1.68) and between hypothyroidism and CTS (N = 64,531, ES = 2.15 [95% CI, 1.64-2.83]). When a meta-analysis limited to the studies that controlled their estimates for some potential confounders, the association between a thyroid disease and CTS disappeared (N = 4,799, ES = 1.17 [95% CI, 0.71-1.92], I(2) = 0%), and the effect size for hypothyroidism largely attenuated (N = 71,133, ES = 1.44 [95% CI, 1.27-1.63], I(2) = 0%). Moreover, there was evidence of publication bias. This meta-analysis found only a modest association between hypothyroidism and CTS. Confounding and publication bias may still account for part of the remaining excess risk. © 2014 Wiley Periodicals, Inc.

  10. Road safety effects of roundabouts: A meta-analysis.

    Science.gov (United States)

    Elvik, Rune

    2017-02-01

    This paper presents a meta-analysis of the road safety effects of converting junctions to roundabouts. 44 studies containing a total of 154 estimates of effect were included. Based on a meta-regression analysis, converting junctions to roundabouts is associated with a reduction of fatal accidents of about 65% and a reduction of injury accidents of about 40%. The mean effect on property-damage-only accidents is ambiguous. Summary estimates of effect are robust for fatal and injury accidents, but vary depending on the model of meta-analysis and the treatment of outlying data points for property-damage-only accidents. A trim-and-fill analysis suggests a weak tendency for publication bias, with modest influence on summary estimates of effect. It is concluded that roundabouts are very effective in reducing traffic fatalities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Child-Centered Play Therapy in the Schools: Review and Meta-Analysis

    Science.gov (United States)

    Ray, Dee C.; Armstrong, Stephen A.; Balkin, Richard S.; Jayne, Kimberly M.

    2015-01-01

    The authors conducted a meta-analysis and systematic review that examined 23 studies evaluating the effectiveness of child centered play therapy (CCPT) conducted in elementary schools. Meta-analysis results were explored using a random effects model for mean difference and mean gain effect size estimates. Results revealed statistically significant…

  12. The effects of reminiscence on psychological well-being in older adults: A meta-analysis

    NARCIS (Netherlands)

    Bohlmeijer, E.; Roemer, M.; Cuijpers, P.; Smit, H.F.E.

    2007-01-01

    This paper presents the results of a meta-analysis to assess the effectiveness of reminiscence on psychological well-being across different target groups and treatment modalities. Fifteen controlled outcome studies were included. An overall effect size of 0.54 was found, indicating a moderate

  13. The effects of reminiscence on psychological well-being in older adults: a meta-analysis.

    NARCIS (Netherlands)

    Bohlmeijer, E.; Roemer, M.; Cuijpers, P.; Smit, H.F.E.

    2007-01-01

    This paper presents the results of a meta-analysis to assess the effectiveness of reminiscence on psychological well-being across different target groups and treatment modalities. Fifteen controlled outcome studies were included. An overall effect size of 0.54 was found, indicating a moderate

  14. Depictive and metric body size estimation in anorexia nervosa and bulimia nervosa: A systematic review and meta-analysis.

    Science.gov (United States)

    Mölbert, Simone Claire; Klein, Lukas; Thaler, Anne; Mohler, Betty J; Brozzo, Chiara; Martus, Peter; Karnath, Hans-Otto; Zipfel, Stephan; Giel, Katrin Elisabeth

    2017-11-01

    A distorted representation of one's own body is a diagnostic criterion and core psychopathology of both anorexia nervosa (AN) and bulimia nervosa (BN). Despite recent technical advances in research, it is still unknown whether this body image disturbance is characterized by body dissatisfaction and a low ideal weight and/or includes a distorted perception or processing of body size. In this article, we provide an update and meta-analysis of 42 articles summarizing measures and results for body size estimation (BSE) from 926 individuals with AN, 536 individuals with BN and 1920 controls. We replicate findings that individuals with AN and BN overestimate their body size as compared to controls (ES=0.63). Our meta-regression shows that metric methods (BSE by direct or indirect spatial measures) yield larger effect sizes than depictive methods (BSE by evaluating distorted pictures), and that effect sizes are larger for patients with BN than for patients with AN. To interpret these results, we suggest a revised theoretical framework for BSE that accounts for differences between depictive and metric BSE methods regarding the underlying body representations (conceptual vs. perceptual, implicit vs. explicit). We also discuss clinical implications and argue for the importance of multimethod approaches to investigate body image disturbance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Meta-analysis of individual registry results enhances international registry collaboration.

    Science.gov (United States)

    Paxton, Elizabeth W; Mohaddes, Maziar; Laaksonen, Inari; Lorimer, Michelle; Graves, Stephen E; Malchau, Henrik; Namba, Robert S; Kärrholm, John; Rolfson, Ola; Cafri, Guy

    2018-03-28

    Background and purpose - Although common in medical research, meta-analysis has not been widely adopted in registry collaborations. A meta-analytic approach in which each registry conducts a standardized analysis on its own data followed by a meta-analysis to calculate a weighted average of the estimates allows collaboration without sharing patient-level data. The value of meta-analysis as an alternative to individual patient data analysis is illustrated in this study by comparing the risk of revision of porous tantalum cups versus other uncemented cups in primary total hip arthroplasties from Sweden, Australia, and a US registry (2003-2015). Patients and methods - For both individual patient data analysis and meta-analysis approaches a Cox proportional hazard model was fit for time to revision, comparing porous tantalum (n = 23,201) with other uncemented cups (n = 128,321). Covariates included age, sex, diagnosis, head size, and stem fixation. In the meta-analysis approach, treatment effect size (i.e., Cox model hazard ratio) was calculated within each registry and a weighted average for the individual registries' estimates was calculated. Results - Patient-level data analysis and meta-analytic approaches yielded the same results with the porous tantalum cups having a higher risk of revision than other uncemented cups (HR (95% CI) 1.6 (1.4-1.7) and HR (95% CI) 1.5 (1.4-1.7), respectively). Adding the US cohort to the meta-analysis led to greater generalizability, increased precision of the treatment effect, and similar findings (HR (95% CI) 1.6 (1.4-1.7)) with increased risk of porous tantalum cups. Interpretation - The meta-analytic technique is a viable option to address privacy, security, and data ownership concerns allowing more expansive registry collaboration, greater generalizability, and increased precision of treatment effects.

  16. Mediating the effect of self-care management intervention in type 2 diabetes: A meta-analysis of 47 randomised controlled trials

    DEFF Research Database (Denmark)

    Minet, Lisbeth; Møller, Sine; Vach, Werner

    2010-01-01

    OBJECTIVE: To perform a meta-analysis assessing the effects of self-care management interventions in improving glycaemic control in type 2 diabetes by analysing the impact of different study characteristics on the effect size. METHODS: A literature search in eight scientific databases up...... to November 2007 included original studies of randomised controlled trials involving adult patients diagnosed with type 2 diabetes and evaluating a self-care management intervention. RESULTS: The 47 included studies yielded 7677 participants. The analysis showed a 0.36% (95% CI 0.21-0.51) improvement...... in glycaemic control in people who received self-care management treatment. In the univariate meta-regression sample size (effect size 0.42%, p=0.007) and follow-up period (effect size 0.49%, p=0.017) were identified to have significant effect on the effect size in favour of small studies and short follow...

  17. Effect of Metformin on Plasma Fibrinogen Concentrations: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials.

    Science.gov (United States)

    Simental-Mendia, Luis E; Pirro, Matteo; Atkin, Stephen L; Banach, Maciej; Mikhailidis, Dimitri P; Sahebkar, Amirhossein

    2018-01-01

    Fibrinogen is a key mediator of thrombosis and it has been implicated in the pathogenesis of atherosclerosis. Because metformin has shown a potential protective effect on different atherothrombotic risk factors, we assessed in this meta-analysis its effect on plasma fibrinogen concentrations. A systematic review and meta-analysis was carried out to identify randomized placebo-controlled trials evaluating the effect of metformin administration on fibrinogen levels. The search included PubMed-Medline, Scopus, ISI Web of Knowledge and Google Scholar databases (by June 2, 2017) and quality of studies was performed according to Cochrane criteria. Quantitative data synthesis was conducted using a random-effects model and sensitivity analysis by the leave-one-out method. Meta-regression analysis was performed to assess the modifiers of treatment response. Meta-analysis of data from 9 randomized placebo-controlled clinical trials with 2302 patients comprising 10 treatment arms did not suggest a significant change in plasma fibrinogen concentrations following metformin therapy (WMD: -0.25 g/L, 95% CI: -0.53, 0.04, p = 0.092). The effect size was robust in the leave-one-out sensitivity analysis and remained non-significant after omission of each single study from the meta-analysis. No significant effect of metformin on plasma fibrinogen concentrations was demonstrated in the current meta-analysis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. The effect of problem-based learning in nursing education: a meta-analysis.

    Science.gov (United States)

    Shin, In-Soo; Kim, Jung-Hee

    2013-12-01

    Problem-based learning (PBL) has been identified as an approach that improves the training of nurses by teaching them how to apply theory to clinical practice and by developing their problem-solving skills, which could be used to overcome environmental constraints within clinical practice. A consensus is emerging that there is a need for systematic reviews and meta-analyses regarding a range of selected topics in nursing education. The purpose of this study was to conduct a meta-analysis of the available literature in order to synthesize the effects of PBL in nursing education. Using a number of databases, we identified studies related to the effectiveness of PBL in nursing. An analysis was conducted on a range of outcome variables, including overall effect sizes and effects of evidence and evaluation levels, learning environment, and study characteristics. We found that the effect of PBL in nursing education is 0.70 standard deviations (medium-to-large effect size). We also found that PBL has positive effects on the outcome domains of satisfaction with training, clinical education, and skill course. These results may act as a guide for nurse educators with regard to the conditions under which PBL is more effective than traditional learning strategies.

  19. Meta-analysis of workplace physical activity interventions.

    Science.gov (United States)

    Conn, Vicki S; Hafdahl, Adam R; Cooper, Pamela S; Brown, Lori M; Lusk, Sally L

    2009-10-01

    Most adults do not achieve adequate physical activity levels. Despite the potential benefits of worksite health promotion, no previous comprehensive meta-analysis has summarized health and physical activity behavior outcomes from such programs. This comprehensive meta-analysis integrated the extant wide range of worksite physical activity intervention research. Extensive searching located published and unpublished intervention studies reported from 1969 through 2007. Results were coded from primary studies. Random-effects meta-analytic procedures, including moderator analyses, were completed in 2008. Effects on most variables were substantially heterogeneous because diverse studies were included. Standardized mean difference (d) effect sizes were synthesized across approximately 38,231 subjects. Significantly positive effects were observed for physical activity behavior (0.21); fitness (0.57); lipids (0.13); anthropometric measures (0.08); work attendance (0.19); and job stress (0.33). The significant effect size for diabetes risk (0.98) is less robust given small sample sizes. The mean effect size for fitness corresponds to a difference between treatment minus control subjects' means on VO2max of 3.5 mL/kg/min; for lipids, -0.2 on the ratio of total cholesterol to high-density lipoprotein; and for diabetes risk, -12.6 mg/dL on fasting glucose. These findings document that some workplace physical activity interventions can improve both health and important worksite outcomes. Effects were variable for most outcomes, reflecting the diversity of primary studies. Future primary research should compare interventions to confirm causal relationships and further explore heterogeneity.

  20. A systematic review and meta-analysis of the effectiveness of nudging to increase fruit and vegetable choice.

    Science.gov (United States)

    Broers, Valérie J V; De Breucker, Céline; Van den Broucke, Stephan; Luminet, Olivier

    2017-10-01

    Nudging refers to interventions that organize the choice architecture in order to alter people's behaviour in a predictable way without forbidding any options or significantly changing their economic incentives. As a strategy to encourage healthy behaviour, nudging can serve as a complement to health education. However, the empirical evidence regarding the effectiveness of nudging as a way to influence food choice remains contradictory. To address this issue, a systematic review and meta-analysis was conducted to test the effects of nudging to encourage people to select more fruit and vegetables. A systematic literature search was performed on PubMed, Medline, PsycInfo, Cochrane library, Scopus and Google Scholar. After quality assessment, 20 articles (23 studies) were retained for narrative synthesis. Twelve articles (14 studies) contained enough information to calculate effect-sizes for meta-analysis using Comprehensive Meta-analysis software. The meta-analysis shows that nudging interventions that aim to increase fruit and/or vegetable choice/sales/servings have a moderately significant effect (d = 0.30), with the largest effect for altering placement (d = 0.39) and combined nudges (d = 0.28). The results of this review provide an indication of the effectiveness of nudging on fruit and vegetable choice in terms of actual effect-sizes, while also highlighting the problems that must be addressed before more definitive conclusions can be drawn. © The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  1. Generous-like flowers: nectar production in two epiphytic bromeliads and a meta-analysis of removal effects.

    Science.gov (United States)

    Ordano, Mariano; Ornelas, Juan Francisco

    2004-08-01

    Animal-pollinated angiosperm plants that respond positively to nectar removal by replenishment invest energy that can entail a reproductive cost. We investigated whether or not nectar removal stimulates replenishment in two hummingbird-pollinated bromeliad species. Nectar replenishment rates were also assessed by removing nectar from manually pollinated flowers because pollination events might be used as signals to save energy by preventing allocation to post-pollination nectar production. Then we synthesized the current understanding of nectar removal effects by reviewing existing published studies with a meta-analysis. The magnitude and significance of estimated nectar removal effects and factors associated with variation in size and direction of nectar removal effects were elucidated with the meta-analysis. We found that both Tillandsia species strongly respond to repeated nectar removal by producing >3 times additional nectar. Nectar secretion patterns were not altered by pollination (stigmatic pollen deposition) and we found no evidence of nectar reabsorption. Although the effect size varied widely across systems and/or environmental conditions, the meta-analysis showed that nectar removal had overall a positive effect on nectar replenishment (mainly among species inhabiting wet tropical habitats such as Tillandsia), and a negative effect on the secretion of additional sugar, suggesting that those plants are resource limited and conservative in the secretion of additional sugar.

  2. Graphics and Statistics for Cardiology: Data visualisation for meta-analysis.

    Science.gov (United States)

    Kiran, Amit; Crespillo, Abel Pérez; Rahimi, Kazem

    2017-01-01

    Graphical displays play a pivotal role in understanding data sets and disseminating results. For meta-analysis, they are instrumental in presenting findings from multiple studies. This report presents guidance to authors wishing to submit graphical displays as part of their meta-analysis to a clinical cardiology journal, such as HeartWhen using graphical displays for meta-analysis, we recommend the following: Use a flow diagram to describe the number of studies returned from the initial search, the inclusion/exclusion criteria applied and the final number of studies used in the meta-analysis.Present results from the meta-analysis using a figure that incorporates a forest plot and underlying (tabulated) statistics, including test for heterogeneity.Use displays such as funnel plot (minimum 10 studies) and Galbraith plot to visually present distribution of effect sizes or associations in order to evaluate small-study effects and publication bias).For meta-regression, the bubble plot is a useful display for assessing associations by study-level factors.Final checks on graphs, such as appropriate use of axis scale, line pattern, text size and graph resolution, should always be performed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  3. Treatment Effect on Recidivism for Juveniles Who Have Sexually Offended: a Multilevel Meta-Analysis.

    Science.gov (United States)

    Ter Beek, Ellis; Spruit, Anouk; Kuiper, Chris H Z; van der Rijken, Rachel E A; Hendriks, Jan; Stams, Geert Jan J M

    2018-04-01

    The current study investigated the effect on recidivism of treatment aimed at juveniles who have sexually offended. It also assessed the potential moderating effect of type of recidivism, and several treatment, participant and study characteristics. In total, 14 published and unpublished primary studies, making use of a comparison group and reporting on official recidivism rates, were included in a multilevel meta-analysis. This resulted in the use of 77 effect sizes, and 1726 participants. A three-level meta-analytic model was used to calculate the combined effect sizes (Cohens d) and to perform moderator analyses. Study quality was assessed with the EPHPP Quality Assessment Tool for Quantitative Studies. A moderate effect size was found (d = 0.37), indicating that the treatment groups achieved an estimated relative reduction in recidivism of 20.5% as compared to comparison groups. However, after controlling for publication bias, a significant treatment effect was no longer found. Type of recidivism did not moderate the effect of treatment, indicating that treatment groups were equally effective for all types of recidivism. Also, no moderating effects of participant or treatment characteristics were found. Regarding study characteristics, a shorter follow up time showed a trend for larger effect sizes, and the effect size calculation based on proportions yielded larger effect sizes than calculation via mean frequency of offending. Implications for future research and clinical practice are discussed.

  4. Meta-Analysis of Workplace Physical Activity Interventions

    Science.gov (United States)

    Conn, Vicki S.; Hafdahl, Adam R.; Cooper, Pamela S.; Brown, Lori M.; Lusk, Sally L.

    2009-01-01

    Context Most adults do not achieve adequate physical activity. Despite the potential benefits of worksite health promotion, no previous comprehensive meta-analysis has summarized health and physical activity behavior outcomes from these programs. This comprehensive meta-analysis integrated the extant wide range of worksite physical activity intervention research. Evidence acquisition Extensive searching located published and unpublished intervention studies reported from 1969 through 2007. Results were coded from primary studies. Random-effects meta-analytic procedures, including moderator analyses, were completed in 2008. Evidence synthesis Effects on most variables were substantially heterogeneous because diverse studies were included. Standardized mean difference (d) effect sizes were synthesized across approximately 38,231 subjects. Significantly positive effects were observed for physical activity behavior (0.21), fitness (0.57), lipids (0.13), anthropometric measures (0.08), work attendance (0.19), and job stress (0.33). The significant effect size for diabetes risk (0.98) is more tentative given small sample sizes. Significant heterogeneity documents intervention effects varied across studies. The mean effect size for fitness corresponds to a difference between treatment minus control subjects' means on V02max of 3.5 mL/kg/min; for lipids, −0.2 on total cholesterol:HDL; and for diabetes risk, −12.6 mg/dL on fasting glucose. Conclusions These findings document that some workplace physical activity interventions can improve both health and important worksite outcomes. Effects were variable for most outcomes, reflecting the diversity of primary studies. Future primary research should compare interventions to confirm causal relationships and further explore heterogeneity. PMID:19765506

  5. Simpson's paradox visualized: The example of the Rosiglitazone meta-analysis

    Directory of Open Access Journals (Sweden)

    Schumacher Martin

    2008-05-01

    Full Text Available Abstract Background Simpson's paradox is sometimes referred to in the areas of epidemiology and clinical research. It can also be found in meta-analysis of randomized clinical trials. However, though readers are able to recalculate examples from hypothetical as well as real data, they may have problems to easily figure where it emerges from. Method First, two kinds of plots are proposed to illustrate the phenomenon graphically, a scatter plot and a line graph. Subsequently, these can be overlaid, resulting in a overlay plot. The plots are applied to the recent large meta-analysis of adverse effects of rosiglitazone on myocardial infarction and to an example from the literature. A large set of meta-analyses is screened for further examples. Results As noted earlier by others, occurrence of Simpson's paradox in the meta-analytic setting, if present, is associated with imbalance of treatment arm size. This is well illustrated by the proposed plots. The rosiglitazone meta-analysis shows an effect reversion if all trials are pooled. In a sample of 157 meta-analyses, nine showed an effect reversion after pooling, though non-significant in all cases. Conclusion The plots give insight on how the imbalance of trial arm size works as a confounder, thus producing Simpson's paradox. Readers can see why meta-analytic methods must be used and what is wrong with simple pooling.

  6. Effects of feedback in a computer-based learning environment on students’ learning outcomes: a meta-analysis

    NARCIS (Netherlands)

    van der Kleij, Fabienne; Feskens, Remco C.W.; Eggen, Theodorus Johannes Hendrikus Maria

    2015-01-01

    In this meta-analysis, we investigated the effects of methods for providing item-based feedback in a computer-based environment on students’ learning outcomes. From 40 studies, 70 effect sizes were computed, which ranged from −0.78 to 2.29. A mixed model was used for the data analysis. The results

  7. The effect of S-adenosylmethionine on cognitive performance in mice: an animal model meta-analysis.

    Directory of Open Access Journals (Sweden)

    Sarah E Montgomery

    Full Text Available Alzheimer's disease (AD is the most frequently diagnosed form of dementia resulting in cognitive impairment. Many AD mouse studies, using the methyl donor S-adenosylmethionine (SAM, report improved cognitive ability, but conflicting results between and within studies currently exist. To address this, we conducted a meta-analysis to evaluate the effect of SAM on cognitive ability as measured by Y maze performance. As supporting evidence, we include further discussion of improvements in cognitive ability, by SAM, as measured by the Morris water maze (MWM.We conducted a comprehensive literature review up to April 2014 based on searches querying MEDLINE, EMBASE, Web of Science, the Cochrane Library and Proquest Theses and Dissertation databases. We identified three studies containing a total of 12 experiments that met our inclusion criteria and one study for qualitative review. The data from these studies were used to evaluate the effect of SAM on cognitive performance according to two scenarios: 1. SAM supplemented folate deficient (SFD diet compared to a folate deficient (FD diet and 2. SFD diet compared to a nutrient complete (NC diet. Hedge's g was used to calculate effect sizes and mixed effects model meta-regression was used to evaluate moderating factors.Our findings showed that the SFD diet was associated with improvements in cognitive performance. SFD diet mice also had superior cognitive performance compared to mice on an NC diet. Further to this, meta-regression analyses indicated a significant positive effect of study quality score and treatment duration on the effect size estimate for both the FD vs SFD analysis and the SFD vs NC analysis.The findings of this meta-analysis demonstrate efficacy of SAM in acting as a cognitive performance-enhancing agent. As a corollary, SAM may be useful in improving spatial memory in patients suffering from many dementia forms including AD.

  8. Effectiveness of massage therapy for shoulder pain: a systematic review and meta-analysis.

    Science.gov (United States)

    Yeun, Young-Ran

    2017-05-01

    [Purpose] This study performed an effect-size analysis of massage therapy for shoulder pain. [Subjects and Methods] The database search was conducted using PubMed, CINAHL, Embase, PsycINFO, RISS, NDSL, NANET, DBpia, and KoreaMed. The meta-analysis was based on 15 studies, covering a total of 635 participants, and used a random effects model. [Results] The effect size estimate showed that massage therapy had a significant effect on reducing shoulder pain for short-term efficacy (SMD: -1.08, 95% CI: -1.51 to -0.65) and for long-term efficacy (SMD: -0.47, 95% CI: -0.71 to -0.23). [Conclusion] The findings from this review suggest that massage therapy is effective at improving shoulder pain. However, further research is needed, especially a randomized controlled trial design or a large sample size, to provide evidence-based recommendations.

  9. Effect of Risk of Bias on the Effect Size of Meta-Analytic Estimates in Randomized Controlled Trials in Periodontology and Implant Dentistry

    Science.gov (United States)

    Faggion, Clovis Mariano; Wu, Yun-Chun; Scheidgen, Moritz; Tu, Yu-Kang

    2015-01-01

    Background Risk of bias (ROB) may threaten the internal validity of a clinical trial by distorting the magnitude of treatment effect estimates, although some conflicting information on this assumption exists. Objective The objective of this study was evaluate the effect of ROB on the magnitude of treatment effect estimates in randomized controlled trials (RCTs) in periodontology and implant dentistry. Methods A search for Cochrane systematic reviews (SRs), including meta-analyses of RCTs published in periodontology and implant dentistry fields, was performed in the Cochrane Library in September 2014. Random-effect meta-analyses were performed by grouping RCTs with different levels of ROBs in three domains (sequence generation, allocation concealment, and blinding of outcome assessment). To increase power and precision, only SRs with meta-analyses including at least 10 RCTs were included. Meta-regression was performed to investigate the association between ROB characteristics and the magnitudes of intervention effects in the meta-analyses. Results Of the 24 initially screened SRs, 21 SRs were excluded because they did not include at least 10 RCTs in the meta-analyses. Three SRs (two from periodontology field) generated information for conducting 27 meta-analyses. Meta-regression did not reveal significant differences in the relationship of the ROB level with the size of treatment effect estimates, although a trend for inflated estimates was observed in domains with unclear ROBs. Conclusion In this sample of RCTs, high and (mainly) unclear risks of selection and detection biases did not seem to influence the size of treatment effect estimates, although several confounders might have influenced the strength of the association. PMID:26422698

  10. Formalizing the definition of meta-analysis in Molecular Ecology.

    Science.gov (United States)

    ArchMiller, Althea A; Bauer, Eric F; Koch, Rebecca E; Wijayawardena, Bhagya K; Anil, Ammu; Kottwitz, Jack J; Munsterman, Amelia S; Wilson, Alan E

    2015-08-01

    Meta-analysis, the statistical synthesis of pertinent literature to develop evidence-based conclusions, is relatively new to the field of molecular ecology, with the first meta-analysis published in the journal Molecular Ecology in 2003 (Slate & Phua 2003). The goal of this article is to formalize the definition of meta-analysis for the authors, editors, reviewers and readers of Molecular Ecology by completing a review of the meta-analyses previously published in this journal. We also provide a brief overview of the many components required for meta-analysis with a more specific discussion of the issues related to the field of molecular ecology, including the use and statistical considerations of Wright's FST and its related analogues as effect sizes in meta-analysis. We performed a literature review to identify articles published as 'meta-analyses' in Molecular Ecology, which were then evaluated by at least two reviewers. We specifically targeted Molecular Ecology publications because as a flagship journal in this field, meta-analyses published in Molecular Ecology have the potential to set the standard for meta-analyses in other journals. We found that while many of these reviewed articles were strong meta-analyses, others failed to follow standard meta-analytical techniques. One of these unsatisfactory meta-analyses was in fact a secondary analysis. Other studies attempted meta-analyses but lacked the fundamental statistics that are considered necessary for an effective and powerful meta-analysis. By drawing attention to the inconsistency of studies labelled as meta-analyses, we emphasize the importance of understanding the components of traditional meta-analyses to fully embrace the strengths of quantitative data synthesis in the field of molecular ecology. © 2015 John Wiley & Sons Ltd.

  11. Meta-Analysis at Middle Age: A Personal History

    Science.gov (United States)

    Glass, Gene V.

    2015-01-01

    The 40-year history of meta-analysis is traced from the vantage point of one of its originators. Research syntheses leading to the first examples of meta-analysis are identified. Early meta-analyses of the literature on psychotherapy outcomes and school class size are recounted. The influence on the development of meta-analysis of several…

  12. Evaluating the Quality of Evidence from a Network Meta-Analysis

    Science.gov (United States)

    Salanti, Georgia; Del Giovane, Cinzia; Chaimani, Anna; Caldwell, Deborah M.; Higgins, Julian P. T.

    2014-01-01

    Systematic reviews that collate data about the relative effects of multiple interventions via network meta-analysis are highly informative for decision-making purposes. A network meta-analysis provides two types of findings for a specific outcome: the relative treatment effect for all pairwise comparisons, and a ranking of the treatments. It is important to consider the confidence with which these two types of results can enable clinicians, policy makers and patients to make informed decisions. We propose an approach to determining confidence in the output of a network meta-analysis. Our proposed approach is based on methodology developed by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group for pairwise meta-analyses. The suggested framework for evaluating a network meta-analysis acknowledges (i) the key role of indirect comparisons (ii) the contributions of each piece of direct evidence to the network meta-analysis estimates of effect size; (iii) the importance of the transitivity assumption to the validity of network meta-analysis; and (iv) the possibility of disagreement between direct evidence and indirect evidence. We apply our proposed strategy to a systematic review comparing topical antibiotics without steroids for chronically discharging ears with underlying eardrum perforations. The proposed framework can be used to determine confidence in the results from a network meta-analysis. Judgements about evidence from a network meta-analysis can be different from those made about evidence from pairwise meta-analyses. PMID:24992266

  13. Identifying Effective Components of Child Maltreatment Interventions: A Meta-analysis.

    Science.gov (United States)

    van der Put, Claudia E; Assink, Mark; Gubbels, Jeanne; Boekhout van Solinge, Noëlle F

    2018-06-01

    There is a lack of knowledge about specific components that make interventions effective in preventing or reducing child maltreatment. The aim of the present meta-analysis was to increase this knowledge by summarizing findings on effects of interventions for child maltreatment and by examining potential moderators of this effect, such as intervention components and study characteristics. Identifying effective components is essential for developing or improving child maltreatment interventions. A literature search yielded 121 independent studies (N = 39,044) examining the effects of interventions for preventing or reducing child maltreatment. From these studies, 352 effect sizes were extracted. The overall effect size was significant and small in magnitude for both preventive interventions (d = 0.26, p child maltreatment. For preventive interventions, larger effect sizes were found for short-term interventions (0-6 months), interventions focusing on increasing self-confidence of parents, and interventions delivered by professionals only. Further, effect sizes of preventive interventions increased as follow-up duration increased, which may indicate a sleeper effect of preventive interventions. For curative interventions, larger effect sizes were found for interventions focusing on improving parenting skills and interventions providing social and/or emotional support. Interventions can be effective in preventing or reducing child maltreatment. Theoretical and practical implications are discussed.

  14. Meta-analysis with R

    CERN Document Server

    Schwarzer, Guido; Rücker, Gerta

    2015-01-01

    This book provides a comprehensive introduction to performing meta-analysis using the statistical software R. It is intended for quantitative researchers and students in the medical and social sciences who wish to learn how to perform meta-analysis with R. As such, the book introduces the key concepts and models used in meta-analysis. It also includes chapters on the following advanced topics: publication bias and small study effects; missing data; multivariate meta-analysis, network meta-analysis; and meta-analysis of diagnostic studies.  .

  15. Meta Analysis of Psychological Interventions’ Effectiveness on the Rate of Depression Among Elderly Iranians in 2000-2010

    Directory of Open Access Journals (Sweden)

    Arghavan Shariat

    2014-04-01

    Full Text Available Objectives: Psychologists and consultants in the recent years have looked for measuring credibility and effectiveness of psychological interventions in the field of depressions among elderly people. In this regard, Meta analysis defines the rate of effect size of psychological interventions by integrating the obtained results from different studies. Methods & Materials: The present research is trying to determine the effectiveness of the psychological interventions on the elderly people’s depression, by using the researching model of Meta analysis. With attention to the different results about the psychological interaction on elderly depression, it seems that a Meta analysis study with accurate rate of psychological interaction on elderly depression will be helpful. On the other hand, Meta analysis can prepare a clear result about this intervention. This method helps us to examine the hypotheses mentioned in different researches.  Results: In this case, 9 psychologically acceptable researches, were selected out of 20 for analysis. The most significant effect (0.58 is related to Sad Hezary et.al and the least amount of effect (0.21 in this research is related to the research of Nemati Dehkordi. The tool in this research was Meta analysis’ check-list The rate the effect is 0.43(P<0.001. Conclusion: The results showed that according to the Cohen’s table of comprehension of the effective rate, the rate of the psychological interventions’ effectiveness on the elderly depression is evaluated intermediate.

  16. Effectiveness of online mindfulness-based interventions in improving mental health: A review and meta-analysis of randomised controlled trials.

    Science.gov (United States)

    Spijkerman, M P J; Pots, W T M; Bohlmeijer, E T

    2016-04-01

    Mindfulness-based interventions (MBIs) are increasingly being delivered through the Internet. Whereas numerous meta-analyses have investigated the effectiveness of face-to-face MBIs in the context of mental health and well-being, thus far a quantitative synthesis of the effectiveness of online MBIs is lacking. The aim of this meta-analysis was to estimate the overall effects of online MBIs on mental health. Fifteen randomised controlled trials were included in this study. A random effects model was used to compute pre-post between-group effect sizes, and the study quality of each of the included trials was rated. Results showed that online MBIs have a small but significant beneficial impact on depression (g=0.29), anxiety (g=0.22), well-being (g=0.23) and mindfulness (g=0.32). The largest effect was found for stress, with a moderate effect size (g=0.51). For stress and mindfulness, exploratory subgroup analyses demonstrated significantly higher effect sizes for guided online MBIs than for unguided online MBIs. In addition, meta-regression analysis showed that effect sizes for stress were significantly moderated by the number of intervention sessions. Effect sizes, however, were not significantly related to study quality. The findings indicate that online MBIs have potential to contribute to improving mental health outcomes, particularly stress. Limitations, directions for future research and practical implications are discussed. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. The Effectiveness of Teamwork Training on Teamwork Behaviors and Team Performance: A Systematic Review and Meta-Analysis of Controlled Interventions.

    Science.gov (United States)

    McEwan, Desmond; Ruissen, Geralyn R; Eys, Mark A; Zumbo, Bruno D; Beauchamp, Mark R

    2017-01-01

    The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k) unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement characteristics. Implications for effective teamwork interventions as well as considerations for future research are discussed.

  18. A meta-analysis of the effects of dropout prevention programs on school absenteeism.

    Science.gov (United States)

    Tanner-Smith, Emily E; Wilson, Sandra Jo

    2013-10-01

    This study reports findings from a systematic review and meta-analysis of literature examining the effects of school dropout prevention and intervention programs on students' school absenteeism outcomes. The meta-analysis synthesized 74 effect sizes measuring posttest differences in school absenteeism outcomes for youth enrolled in dropout prevention programs relative to a comparison group. Although results from randomized controlled trials indicated significant beneficial program effects, findings from quasi-experimental studies indicated no significant beneficial or detrimental effects. Examination of study characteristics suggested that dropout programs may have beneficial effects on school absenteeism among primarily male samples, and younger samples. Although no single type of intervention program was consistently more effective than others, vocational oriented and supplemental academic training programs showed some promise. However, the inconsistency in results and the possibility of small study bias mean the quality of evidence in this literature is low; at this time there is not enough evidence to conclude that dropout prevention programs have a universal impact on youth's school absenteeism outcomes.

  19. Steep Delay Discounting and Addictive Behavior: A Meta-Analysis of Continuous Associations

    Science.gov (United States)

    Amlung, Michael; Vedelago, Lana; Acker, John; Balodis, Iris; MacKillop, James

    2016-01-01

    Aims To synthesize continuous associations between delayed reward discounting (DRD) and both addiction severity and quantity-frequency (QF); to examine moderators of these relationships; and to investigate publication bias. Methods Meta-analysis of published studies examining continuous associations between DRD and addictive behaviors. Published, peer-reviewed studies on addictive behaviors (alcohol, tobacco, cannabis, stimulants, opiates, and gambling) were identified via PubMed, MEDLINE, and PsycInfo. Studies were restricted to DRD measures of monetary gains. Random effects meta-analysis was conducted using Pearson’s r as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger’s tests, meta-regression of publication year and effect size, and imputation of missing studies. Results The primary meta-analysis revealed a small magnitude effect size that was highly significant (r = 0.14, p addictive behavior (p = 0.30) or DRD assessment (p = 0.90). Indices of publication bias suggested a modest impact of unpublished findings. Conclusions Delayed reward discounting is robustly associated with continuous measures of addiction severity and quantity-frequency. This relation is generally robust across type of addictive behavior and delayed reward discounting assessment modality. PMID:27450931

  20. Effect of biotin on milk performance of dairy cattle: a meta-analysis.

    Science.gov (United States)

    Chen, B; Wang, C; Wang, Y M; Liu, J X

    2011-07-01

    A meta-analysis of the effect of biotin on production outcomes of dairy cattle was conducted following a literature review. A total of 11 studies from 9 papers, with information on the milk production and composition data from a total number of 238 cows were extracted and analyzed using meta-analysis software in Stata. Estimated size of effect of biotin was calculated for dry matter intake (DMI), milk production, and composition. Heterogeneity was not significant for all of the parameters (the highest I(2)=12%). Therefore, fixed effects models were used for analysis. With the addition of biotin to lactating dairy cattle, DMI and milk production increased by 0.87 and 1.66 kg/d. No significant effect on percentage of milk fat and milk protein was observed. Additionally, Begg's test indicated no evidence of substantial publication bias for all variables. The influence analysis shows that the removal of any study did not change the direction or significance of the point estimates. It can be concluded that the use of biotin supplements increases DMI and milk yield in lactating dairy cows. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  1. The number of patients and events required to limit the risk of overestimation of intervention effects in meta-analysis--a simulation study

    DEFF Research Database (Denmark)

    Thorlund, Kristian; Imberger, Georgina; Walsh, Michael

    2011-01-01

    Meta-analyses including a limited number of patients and events are prone to yield overestimated intervention effect estimates. While many assume bias is the cause of overestimation, theoretical considerations suggest that random error may be an equal or more frequent cause. The independent impact...... of random error on meta-analyzed intervention effects has not previously been explored. It has been suggested that surpassing the optimal information size (i.e., the required meta-analysis sample size) provides sufficient protection against overestimation due to random error, but this claim has not yet been...

  2. Effects of physiological aging on mismatch negativity: a meta-analysis.

    Science.gov (United States)

    Cheng, Chia-Hsiung; Hsu, Wan-Yu; Lin, Yung-Yang

    2013-11-01

    Mismatch negativity (MMN) is a promising window on how the functional integrity of auditory sensory memory and change discrimination is modulated by age and relevant clinical conditions. However, the effects of aging on MMN have remained somewhat elusive, particularly at short interstimulus intervals (ISIs). We performed a meta-analysis of peer-reviewed MMN studies that had targeted both young and elderly adults to estimate the mean effect size. Nine studies, consisting of 29 individual investigations, were included and the final total study population consisted of 182 young and 165 elderly subjects. The effects of different deviant types and duration of ISIs on the effect size were assessed. The overall mean effect size was 0.63 (95% CI at 0.43-0.82). The effect sizes for long ISI (>2s, effect size 0.68, 95% CI at 0.31-1.06) and short ISI (aging-related decrease in MMN responses to duration and frequency changes at short ISIs. It was also interesting to note that the effect size was about 25% larger for duration deviant condition compared to the frequency deviant condition. In conclusion, a reduced MMN response to duration and frequency deviants is a robust feature among the aged adults, which suggests that there has been a decline in the functional integrity of central auditory processing in this population. © 2013.

  3. The Effectiveness of Teamwork Training on Teamwork Behaviors and Team Performance: A Systematic Review and Meta-Analysis of Controlled Interventions

    Science.gov (United States)

    McEwan, Desmond; Ruissen, Geralyn R.; Eys, Mark A.; Zumbo, Bruno D.; Beauchamp, Mark R.

    2017-01-01

    The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k) unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement characteristics. Implications for effective teamwork interventions as well as considerations for future research are discussed. PMID:28085922

  4. The Effectiveness of Teamwork Training on Teamwork Behaviors and Team Performance: A Systematic Review and Meta-Analysis of Controlled Interventions.

    Directory of Open Access Journals (Sweden)

    Desmond McEwan

    Full Text Available The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement characteristics. Implications for effective teamwork interventions as well as considerations for future research are discussed.

  5. A Meta-Analysis of Mathematics and Working Memory: Moderating Effects of Working Memory Domain, Type of Mathematics Skill, and Sample Characteristics

    Science.gov (United States)

    Peng, Peng; Namkung, Jessica; Barnes, Marcia; Sun, Congying

    2016-01-01

    The purpose of this meta-analysis was to determine the relation between mathematics and working memory (WM) and to identify possible moderators of this relation including domains of WM, types of mathematics skills, and sample type. A meta-analysis of 110 studies with 829 effect sizes found a significant medium correlation of mathematics and WM, r…

  6. Game-based digital interventions for depression therapy: a systematic review and meta-analysis.

    Science.gov (United States)

    Li, Jinhui; Theng, Yin-Leng; Foo, Schubert

    2014-08-01

    The aim of this study was to review the existing literature on game-based digital interventions for depression systematically and examine their effectiveness through a meta-analysis of randomized controlled trials (RCTs). Database searching was conducted using specific search terms and inclusion criteria. A standard meta-analysis was also conducted of available RCT studies with a random effects model. The standard mean difference (Cohen's d) was used to calculate the effect size of each study. Nineteen studies were included in the review, and 10 RCTs (eight studies) were included in the meta-analysis. Four types of game interventions-psycho-education and training, virtual reality exposure therapy, exercising, and entertainment-were identified, with various types of support delivered and populations targeted. The meta-analysis revealed a moderate effect size of the game interventions for depression therapy at posttreatment (d=-0.47 [95% CI -0.69 to -0.24]). A subgroup analysis showed that interventions based on psycho-education and training had a smaller effect than those based on the other forms, and that self-help interventions yielded better outcomes than supported interventions. A higher effect was achieved when a waiting list was used as the control. The review and meta-analysis support the effectiveness of game-based digital interventions for depression. More large-scale, high-quality RCT studies with sufficient long-term data for treatment evaluation are needed.

  7. Predicted effect size of lisdexamfetamine treatment of attention deficit/hyperactivity disorder (ADHD) in European adults: Estimates based on indirect analysis using a systematic review and meta-regression analysis.

    Science.gov (United States)

    Fridman, M; Hodgkins, P S; Kahle, J S; Erder, M H

    2015-06-01

    There are few approved therapies for adults with attention-deficit/hyperactivity disorder (ADHD) in Europe. Lisdexamfetamine (LDX) is an effective treatment for ADHD; however, no clinical trials examining the efficacy of LDX specifically in European adults have been conducted. Therefore, to estimate the efficacy of LDX in European adults we performed a meta-regression of existing clinical data. A systematic review identified US- and Europe-based randomized efficacy trials of LDX, atomoxetine (ATX), or osmotic-release oral system methylphenidate (OROS-MPH) in children/adolescents and adults. A meta-regression model was then fitted to the published/calculated effect sizes (Cohen's d) using medication, geographical location, and age group as predictors. The LDX effect size in European adults was extrapolated from the fitted model. Sensitivity analyses performed included using adult-only studies and adding studies with placebo designs other than a standard pill-placebo design. Twenty-two of 2832 identified articles met inclusion criteria. The model-estimated effect size of LDX for European adults was 1.070 (95% confidence interval: 0.738, 1.401), larger than the 0.8 threshold for large effect sizes. The overall model fit was adequate (80%) and stable in the sensitivity analyses. This model predicts that LDX may have a large treatment effect size in European adults with ADHD. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  8. Meta-analysis in plant pathology: synthesizing research results.

    Science.gov (United States)

    Rosenberg, M S; Garrett, K A; Su, Z; Bowden, R L

    2004-09-01

    ABSTRACT Meta-analysis is a set of statistical procedures for synthesizing research results from a number of different studies. An estimate of a statistical effect, such as the difference in disease severity for plants with or without a management treatment, is collected from each study along with a measure of the variance of the estimate of the effect. Combining results from different studies will generally result in increased statistical power so that it is easier to detect small effects. Combining results from different studies may also make it possible to compare the size of the effect as a function of other predictor variables such as geographic region or pathogen species. We present a review of the basic methodology for meta-analysis. We also present an example of meta-analysis of the relationship between disease severity and yield loss for foliar wheat diseases, based on data collected from a decade of fungicide and nematicide test results.

  9. Appealing to fear: A Meta-Analysis of Fear Appeal Effectiveness and Theories

    Science.gov (United States)

    Tannenbaum, Melanie B.; Hepler, Justin; Zimmerman, Rick S.; Saul, Lindsey; Jacobs, Samantha; Wilson, Kristina; Albarracin, Dolores

    2018-01-01

    Fear appeals are a polarizing issue, with proponents confident in their efficacy and opponents confident that they backfire. We present the results of a comprehensive meta-analysis investigating fear appeals’ effectiveness for influencing attitudes, intentions, and behaviors. We tested predictions from a large number of theories, the majority of which have never been tested meta-analytically until now. Studies were included if they contained a treatment group exposed to a fear appeal, a valid comparison group, a manipulation of depicted fear, a measure of attitudes, intentions, or behaviors concerning the targeted risk or recommended solution, and adequate statistics to calculate effect sizes. The meta-analysis included 127 papers (9% unpublished) yielding 248 independent samples (NTotal = 27,372) collected from diverse populations. Results showed a positive effect of fear appeals on attitudes, intentions, and behaviors, with the average effect on a composite index being random-effects d¯ = 0.29. Moderation analyses based on prominent fear appeal theories showed that the effectiveness of fear appeals increased when the message included efficacy statements, depicted high susceptibility and severity, recommended one-time only (vs. repeated) behaviors, and targeted audiences that included a larger percentage of female message recipients. Overall, we conclude that (a) fear appeals are effective at positively influencing attitude, intentions, and behaviors, (b) there are very few circumstances under which they are not effective, and (c) there are no identified circumstances under which they backfire and lead to undesirable outcomes. PMID:26501228

  10. Non-cognate translation priming in masked priming lexical decision experiments: A meta-analysis.

    Science.gov (United States)

    Wen, Yun; van Heuven, Walter J B

    2017-06-01

    The masked translation priming paradigm has been widely used in the last 25 years to investigate word processing in bilinguals. Motivated by studies reporting mixed findings, in particular for second language (L2) to first language (L1) translation priming, we conducted, for the first time in the literature, a meta-analysis of 64 masked priming lexical decision experiments across 24 studies to assess the effect sizes of L1-L2 and L2-L1 non-cognate translation priming effects in bilinguals. Our meta-analysis also investigated the influence of potential moderators of translation priming effects. The results provided clear evidence of significant translation priming effects for both directions, with L1-L2 translation priming significantly larger than L2-L1 translation priming (i.e., effect size of 0.86 vs. 0.31). The analyses also revealed that L1-L2 translation effect sizes were moderated by the interval between prime and target (ISI), whereas L2-L1 translation effect sizes were modulated by the number of items per cell. Theoretical and methodological implications of this meta-analysis are discussed and recommendations for future studies are provided.

  11. Quality of Life in Autism across the Lifespan: A Meta-Analysis

    Science.gov (United States)

    van Heijst, Barbara F. C.; Geurts, Hilde M.

    2015-01-01

    Autism is a lifelong neurodevelopmental disorder, with a known impact on quality of life. Yet the developmental trajectory of quality of life is not well understood. First, the effect of age on quality of life was studied with a meta-analysis. Our meta-analysis included 10 studies (published between 2004 and 2012) with a combined sample size of…

  12. The relationship between persuasive technology principles, adherence and effect of web-Based interventions for mental health: A meta-analysis.

    Science.gov (United States)

    Wildeboer, Gina; Kelders, Saskia M; van Gemert-Pijnen, Julia E W C

    2016-12-01

    Research has shown that web-based interventions concerning mental health can be effective, although there is a broad range in effect sizes. Why some interventions are more effective than others is not clear. Persuasive technology is one of the aspects which has a positive influence on changing attitude and/or behavior, and can contribute to better outcomes. According to the Persuasive Systems Design Model there are various principles that can be deployed. It is unknown whether the number and combinations of principles used in a web-based intervention affect the effectiveness. Another issue in web-based interventions is adherence. Little is known about the relationship of adherence on the effectiveness of web-based interventions. This study examines whether there is a relationship between the number and combinations of persuasive technology principles used in web-based interventions and the effectiveness. Also the influence of adherence on effectiveness of web-based interventions is investigated. This study elaborates on the systematic review by [37] and therefore the articles were derived from that study. Only web-based interventions were included that were intended to be used on more than one occasion and studies were excluded when no information on adherence was provided. 48 interventions targeted at mental health were selected for the current study. A within-group (WG) and between-group (BG) meta-analysis were performed and subsequently subgroup analyses regarding the relationship between the number and combinations of persuasive technology principles and effectiveness. The influence of adherence on the effectiveness was examined through a meta-regression analysis. For the WG meta-analysis 40 treatment groups were included. The BG meta-analysis included 19 studies. The mean pooled effect size in the WG meta-analysis was large and significant (Hedges' g=0.94), while for the BG meta-analysis this was moderate to large and significant (Hedges' g=0.78) in favor of

  13. Ionizing radiation, antioxidant response and oxidative damage: A meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Einor, D., E-mail: daniel@einor.com [Department of Biological Sciences, University of South Carolina, Columbia, SC 29208 (United States); Bonisoli-Alquati, A., E-mail: andreabonisoli@gmail.com [Department of Biological Sciences, University of South Carolina, Columbia, SC 29208 (United States); School of Renewable Natural Resources, Louisiana State University AgCenter, Baton Rouge, LA 70803 (United States); Costantini, D., E-mail: davidcostantini@libero.it [Department of Biology, University of Antwerp, Wilrijk, B-2610, Antwerp (Belgium); Mousseau, T.A., E-mail: mousseau@sc.edu [Department of Biological Sciences, University of South Carolina, Columbia, SC 29208 (United States); Faculty of Bioscience and Biotechnology, Chubu University, Kasugai (Japan); Møller, A.P., E-mail: anders.moller@u-psud.fr [Laboratoire d' Ecologie, Systématique et Evolution, CNRS UMR 8079, Université Paris-Sud, Bâtiment 362, F-91405 Orsay Cedex (France)

    2016-04-01

    One mechanism proposed as a link between exposure to ionizing radiation and detrimental effects on organisms is oxidative damage. To test this hypothesis, we surveyed the scientific literature on the effects of chronic low-dose ionizing radiation (LDIR) on antioxidant responses and oxidative damage. We found 40 publications and 212 effect sizes for antioxidant responses and 288 effect sizes for effects of oxidative damage. We performed a meta-analysis of signed and unsigned effect sizes. We found large unsigned effects for both categories (0.918 for oxidative damage; 0.973 for antioxidant response). Mean signed effect size weighted by sample size was 0.276 for oxidative damage and − 0.350 for antioxidant defenses, with significant heterogeneity among effects for both categories, implying that ionizing radiation caused small to intermediate increases in oxidative damage and small to intermediate decreases in antioxidant defenses. Our estimates are robust, as shown by very high fail-safe numbers. Species, biological matrix (tissue, blood, sperm) and age predicted the magnitude of effects for oxidative damage as well as antioxidant response. Meta-regression models showed that effect sizes for oxidative damage varied among species and age classes, while effect sizes for antioxidant responses varied among species and biological matrices. Our results are consistent with the description of mechanisms underlying pathological effects of chronic exposure to LDIR. Our results also highlight the importance of resistance to oxidative stress as one possible mechanism associated with variation in species responses to LDIR-contaminated areas. - Highlights: • There is interest in variation in metabolic effects of chronic low-dose ionizing radiation • A random effect meta-analysis of effect sizes of radioactive contamination was performed • We found significant effects of radiation on oxidative damage and antioxidant response • We found significant heterogeneity among

  14. Determining The Factors Affecting Fruit Hardness of Different Peach Types with Meta Analysis

    Directory of Open Access Journals (Sweden)

    Hande Küçükönder

    2014-09-01

    Full Text Available The aim of this study is to determine the factor effective in determining the hardness of Caterina, Suidring, Royal Glory and Tirrenia peach types using meta analysis. In the study, the impact force (Fi and the contact time (tc were detected and the impulse values (I that are expressed as independent variable in the area under the curve were calculated in the measurements performed using the technique of a low-mass lateral impactor multiplicated with peach. Using the theory of elasticity, the independent variables were determined as Fmax (maximum impact force, contact time (tmax, Fmax/tmax, 1/tmax, 1/tmax2,5, Fmax/tmax 1.25 and Fmax2.5 parameters. The correlation coefficient values showing the relationship between these parameters and the dependent variable Magness-Taylor force (MT were calculated and were combined with meta-analysis by using the Hunter-Schmid and Fisher’s Z methods. The Cohen’s classification criterion was used in evaluating the resulting mean effect size (combined correlation value and in determining its direction. As a result of the meta-analysis, the mean effect size according to Hunter-Schmid method was found 0.436 (0.371-0.497 positively directed in 95% confidence interval, while it was found 0.468 (0.390-0.545 according to Fisher’s Z method. The effect sizes in both methods were determined “mid-level” according to the Cohen’s classification. When the significance level of the studies was analyzed with the Z test, all of the ones that taken into the meta analysis has been found statistically significant. As a result of the meta analysis in this study evaluating the relationship of peach types with the fruit hardness, the mean effect size has been found to reach “strong level”. Consequently, “maximum shock acceleration” was found to be a more effective factor comparing to the other factors in determining the the fruit hardness according to the results of meta analysis applied in both methods.

  15. The correlation of social support with mental health: A meta-analysis.

    Science.gov (United States)

    Harandi, Tayebeh Fasihi; Taghinasab, Maryam Mohammad; Nayeri, Tayebeh Dehghan

    2017-09-01

    Social support is an important factor that can affect mental health. In recent decades, many studies have been done on the impact of social support on mental health. The purpose of the present study is to investigate the effect size of the relationship between social support and mental health in studies in Iran. This meta-analysis was carried out in studies that were performed from 1996 through 2015. Databases included SID and Magiran, the comprehensive portal of human sciences, Noor specialized magazine databases, IRANDOC, Proquest, PubMed, Scopus, ERIC, Iranmedex and Google Scholar. The keywords used to search these websites included "mental health or general health," and "Iran" and "social support." In total, 64 studies had inclusion criteria meta-analysis. In order to collect data used from a meta-analysis worksheet that was made by the researcher and for data analysis software, CMA-2 was used. The mean of effect size of the 64 studies in the fixed-effect model and random-effect model was obtained respectively as 0.356 and 0.330, which indicated the moderate effect size of social support on mental health. The studies did not have publication bias, and enjoyed a heterogeneous effect size. The target population and social support questionnaire were moderator variables, but sex, sampling method, and mental health questionnaire were not moderator variables. Regarding relatively high effect size of the correlation between social support and mental health, it is necessary to predispose higher social support, especially for women, the elderly, patients, workers, and students.

  16. Lead and Conduct Problems: A Meta-Analysis

    Science.gov (United States)

    Marcus, David K.; Fulton, Jessica J.; Clarke, Erin J.

    2010-01-01

    This meta-analysis examined the association between conduct problems and lead exposure. Nineteen studies on 8,561 children and adolescents were included. The average "r" across all 19 studies was 0.19 (p less than 0.001), which is considered a medium effect size. Studies that assessed lead exposure using hair element analysis yielded…

  17. Impact of Mobile Assisted Language Learning (MALL on EFL: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Imtiaz Hassan Taj

    2016-04-01

    Full Text Available Mobile Assisted Language Learning (MALL has emerged as a potential tool in the instruction of English as a foreign language (EFL. Meta-analysis of 13 studies published between year 2008 and 2015 was conducted. Four point criteria for the selection of studies for analysis is based on the year of publication, quasi-experimental design, pretest and posttest method and finally use of mobile device for intervention. Findings of the analysis suggest that MALL has fostered the EFL instruction. Overall effect size was (d = 0.8 which is considered a large effect size. Keywords: MALL, technology assisted language learning, EFL, vocabulary acquisition, vocabulary instruction, meta-analysis

  18. GWAMA: software for genome-wide association meta-analysis

    Directory of Open Access Journals (Sweden)

    Mägi Reedik

    2010-05-01

    Full Text Available Abstract Background Despite the recent success of genome-wide association studies in identifying novel loci contributing effects to complex human traits, such as type 2 diabetes and obesity, much of the genetic component of variation in these phenotypes remains unexplained. One way to improving power to detect further novel loci is through meta-analysis of studies from the same population, increasing the sample size over any individual study. Although statistical software analysis packages incorporate routines for meta-analysis, they are ill equipped to meet the challenges of the scale and complexity of data generated in genome-wide association studies. Results We have developed flexible, open-source software for the meta-analysis of genome-wide association studies. The software incorporates a variety of error trapping facilities, and provides a range of meta-analysis summary statistics. The software is distributed with scripts that allow simple formatting of files containing the results of each association study and generate graphical summaries of genome-wide meta-analysis results. Conclusions The GWAMA (Genome-Wide Association Meta-Analysis software has been developed to perform meta-analysis of summary statistics generated from genome-wide association studies of dichotomous phenotypes or quantitative traits. Software with source files, documentation and example data files are freely available online at http://www.well.ox.ac.uk/GWAMA.

  19. [Effect of acupuncture therapy on patients with low back pain: a Meta-analysis].

    Science.gov (United States)

    Liang, Fei-fan; Chen, Wei-ye; Chen, Bo; Xu, Qin-guang; Zhan, Hong-sheng

    2016-05-01

    To systematically review the clinical efficacy of acupuncture on the patients with low back pain (LBP). Randomized controlled trials (RCTs) about pure acupuncture therapy versus other treatments in treating LBP were electronically searched in PubMed, CBM, EMbase, The Cochrane Library, CNKI, VIP and Wanfang Data from January 2004 to May 2014. The observed index on the results were the changed scores of VAS, ODI, JOA and RMDQ. Two reviewers independently screened the literatures according to the inclusion and exclusion criteria, as well as the extracted data, and assessed the methodological quality. The results of Meta-analysis was conducted by RevMan 5.2 software. Ten RCTs involved 751 patients were finally included. The results of Meta-analysis indicated that the role of pure acupuncture group in improving the VAS score was better than that of the control group, and the combined effect size was RR = -.32, 95% CI (-1.41, -1.22); Z=27.28, Pacupuncture group in improving the ODI score was better than that of the control group, and the combined effect size was RR = -5.07, 95% CI (-7.50, -2.65); Z=4.10, Pacupuncture group on improved JOA score was better than that of the control group and the combined effect size was RR=2.83, 95% CI (2.02, 3.63), Z=6.90, Pacupuncture group in improving the RMDQ score was better than that of the control group, and the combined effect size was RR = -2.80, 95% CI (-3.49, -2.11), Z=7.95, Pacupuncture may have a favorable effect on self-reported pain and functional limitations in LBP patients.

  20. The effect of loving-kindness meditation on positive emotions: a meta-analytic review.

    Science.gov (United States)

    Zeng, Xianglong; Chiu, Cleo P K; Wang, Rong; Oei, Tian P S; Leung, Freedom Y K

    2015-01-01

    While it has been suggested that loving-kindness meditation (LKM) is an effective practice for promoting positive emotions, the empirical evidence in the literature remains unclear. Here, we provide a systematic review of 24 empirical studies (N = 1759) on LKM with self-reported positive emotions. The effect of LKM on positive emotions was estimated with meta-analysis, and the influence of variations across LKM interventions was further explored with subgroup analysis and meta-regression. The meta-analysis showed that (1) medium effect sizes for LKM interventions on daily positive emotions in both wait-list controlled RCTs and non-RCT studies; and (2) small to large effect sizes for the on-going practice of LKM on immediate positive emotions across different comparisons. Further analysis showed that (1) interventions focused on loving-kindness had medium effect size, but interventions focused on compassion showed small effect sizes; (2) the length of interventions and the time spent on meditation did not influence the effect sizes, but the studies without didactic components in interventions had small effect sizes. A few individual studies reported that the nature of positive emotions and individual differences also influenced the results. In sum, LKM practice and interventions are effective in enhancing positive emotions, but more studies are needed to identify the active components of the interventions, to compare different psychological operations, and to explore the applicability in clinical populations.

  1. A Technology-Organization-Environment Perspective on Eco-effectiveness: A Meta-analysis

    Directory of Open Access Journals (Sweden)

    Josephine LL Chong

    2017-03-01

    Full Text Available In this research, we perform a meta-analysis to explain how organizations are deploying technologies to enforce organizational sustainability by meeting the goal of eco-effectiveness. Prior studies have studied the influences on the adoption of technologies using the Technology-Organisation-Environment (TOE model that incorporate some aspects of technological, organizational or environmental factors. We collected prior research to test the factors of the TOE model to ascertain their relative impact and strength. Our meta-analysis found eight additional technological and organizational factors. We found strong support for IT infrastructure, perceived direct benefits, top management support, and competitive pressure. Moderate support for compatibility, technological readiness, perceived indirect benefits, knowledge (human resources, organizational size, attitudes towards innovation, learning culture, pressure from trade partners (industry characteristics and regulatory support. Lastly, weak support was found for relative advantage, complexity, perceived risks and information learning culture. Only two dimensions, financial resources and environmental uncertainty failed to reach statistical significance.

  2. The Influence of Study-Level Inference Models and Study Set Size on Coordinate-Based fMRI Meta-Analyses

    Directory of Open Access Journals (Sweden)

    Han Bossier

    2018-01-01

    Full Text Available Given the increasing amount of neuroimaging studies, there is a growing need to summarize published results. Coordinate-based meta-analyses use the locations of statistically significant local maxima with possibly the associated effect sizes to aggregate studies. In this paper, we investigate the influence of key characteristics of a coordinate-based meta-analysis on (1 the balance between false and true positives and (2 the activation reliability of the outcome from a coordinate-based meta-analysis. More particularly, we consider the influence of the chosen group level model at the study level [fixed effects, ordinary least squares (OLS, or mixed effects models], the type of coordinate-based meta-analysis [Activation Likelihood Estimation (ALE that only uses peak locations, fixed effects, and random effects meta-analysis that take into account both peak location and height] and the amount of studies included in the analysis (from 10 to 35. To do this, we apply a resampling scheme on a large dataset (N = 1,400 to create a test condition and compare this with an independent evaluation condition. The test condition corresponds to subsampling participants into studies and combine these using meta-analyses. The evaluation condition corresponds to a high-powered group analysis. We observe the best performance when using mixed effects models in individual studies combined with a random effects meta-analysis. Moreover the performance increases with the number of studies included in the meta-analysis. When peak height is not taken into consideration, we show that the popular ALE procedure is a good alternative in terms of the balance between type I and II errors. However, it requires more studies compared to other procedures in terms of activation reliability. Finally, we discuss the differences, interpretations, and limitations of our results.

  3. Effects of music therapy for children and adolescents with psychopathology: a meta-analysis.

    Science.gov (United States)

    Gold, Christian; Voracek, Martin; Wigram, Tony

    2004-09-01

    The objectives of this review were to examine the overall efficacy of music therapy for children and adolescents with psychopathology, and to examine how the size of the effect of music therapy is influenced by the type of pathology, client's age, music therapy approach, and type of outcome. Eleven studies were included for analysis, which resulted in a total of 188 subjects for the meta-analysis. Effect sizes from these studies were combined, with weighting for sample size, and their distribution was examined. After exclusion of an extreme positive outlying value, the analysis revealed that music therapy has a medium to large positive effect (ES =.61) on clinically relevant outcomes that was statistically highly significant (p <.001) and statistically homogeneous. No evidence of a publication bias was identified. Effects tended to be greater for behavioural and developmental disorders than for emotional disorders; greater for eclectic, psychodynamic, and humanistic approaches than for behavioural models; and greater for behavioural and developmental outcomes than for social skills and self-concept. Implications for clinical practice and research are discussed.

  4. Treatment effects between monotherapy of donepezil versus combination with memantine for Alzheimer disease: A meta-analysis.

    Science.gov (United States)

    Chen, Ruey; Chan, Pi-Tuan; Chu, Hsin; Lin, Yu-Cih; Chang, Pi-Chen; Chen, Chien-Yu; Chou, Kuei-Ru

    2017-01-01

    This is the first meta-analysis to compare the treatment effects and safety of administering donepezil alone versus a combination of memantine and donepezil to treat patients with moderate to severe Alzheimer Disease, particularly regarding cognitive functions, behavioral and psychological symptoms in dementia (BPSD), and global functions. PubMed, Medline, Embase, PsycINFO, and Cochrane databases were used to search for English and non-English articles for inclusion in the meta-analysis to evaluate the effect size and incidence of adverse drug reactions of different treatments. Compared with patients who received donepezil alone, those who received donepezil in combination with memantine exhibited limited improvements in cognitive functions (g = 0.378, p Alzheimer Disease.

  5. A Meta-Analysis of Massage Therapy Research

    Science.gov (United States)

    Moyer, Christopher A.; Rounds, James; Hannum, James W.

    2004-01-01

    Massage therapy (MT) is an ancient form of treatment that is now gaining popularity as part of the complementary and alternative medical therapy movement. A meta-analysis was conducted of studies that used random assignment to test the effectiveness of MT. Mean effect sizes were calculated from 37 studies for 9 dependent variables. Single…

  6. A Meta-Analysis of the Predictors of Cyberbullying Perpetration and Victimization

    Science.gov (United States)

    Guo, Siying

    2016-01-01

    Previous studies so far have investigated various aspects of cyberbullying. Using meta-analytic approaches, the study was primarily to determine the target factors predicting individuals' perpetration and victimization in cyberbullying. A meta-analysis of 77 studies containing 418 primary effect sizes was conducted to exam the relative magnitude…

  7. The Effect of Cognitive-Behavioral Therapies in Treatment of Addicts in Iran by Systematic Review and Meta-Analysis Method

    Directory of Open Access Journals (Sweden)

    Shahram Mami

    2017-03-01

    Full Text Available Background and Objectives: Addiction and its complications is one of the major problems in the world and various types of psychotherapy approaches are used for its treatment. Among these approaches, cognitive-behavioral therapies have been widely used for the treatment of addiction in recent decades. The aim of this study was to estimate the effect of cognitive-behavioral therapies on the treatment of addicts in Iran by systematic review and meta-analysis method. Methods: Meta-analysis method was used, without limitation, to investigate all internal databases as well as Medlib, Sid, Magiran, Google Scholar, PubMed, Scopuse, Iranmedex, and ISI. Finally, 12 out of 63 articles were entered into the meta-analysis. Meta-regression was used to investigate the heterogeneity of the studies. Results: In this study, 12 articles were investigated, which increased to 25 studies, including therapeutic approaches. In 6 studies, no significant difference was observed in the experimental group before and after intervention, and in the remaining 19 studies the difference was significant. Combination of the results of 25 studies and using a random effects model of meta-analysis showed that cognitive-behavioral therapy was effective in the treatment of addiction (p<0.001. The standardized effect size in the experimental group before and after cognitive-behavioral therapy, was estimated to be -2.08 and its 95% confidence interval was -1.57 to -2.58. The standardized effect size in control and experimental groups after cognitive-behavioral therapy was estimated 0.40 and its 95% confidence interval was 0.10 to 0.70. Conclusion: Given that cognitive-behavioral therapy is effective in reducing addiction and its symptoms, this method can be used as a common treatment of addiction.

  8. The effectiveness of problem-based learning on development of nursing students' critical thinking: a systematic review and meta-analysis.

    Science.gov (United States)

    Kong, Ling-Na; Qin, Bo; Zhou, Ying-qing; Mou, Shao-yu; Gao, Hui-Ming

    2014-03-01

    The objective of this systematic review and meta-analysis was to estimate the effectiveness of problem-based learning in developing nursing students' critical thinking. Searches of PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Proquest, Cochrane Central Register of Controlled Trials (CENTRAL) and China National Knowledge Infrastructure (CNKI) were undertaken to identify randomized controlled trails from 1965 to December 2012, comparing problem-based learning with traditional lectures on the effectiveness of development of nursing students' critical thinking, with no language limitation. The mesh-terms or key words used in the search were problem-based learning, thinking, critical thinking, nursing, nursing education, nurse education, nurse students, nursing students and pupil nurse. Two reviewers independently assessed eligibility and extracted data. Quality assessment was conducted independently by two reviewers using the Cochrane Collaboration's Risk of Bias Tool. We analyzed critical thinking scores (continuous outcomes) using a standardized mean difference (SMD) or weighted mean difference (WMD) with a 95% confidence intervals (CIs). Heterogeneity was assessed using the Cochran's Q statistic and I(2) statistic. Publication bias was assessed by means of funnel plot and Egger's test of asymmetry. Nine articles representing eight randomized controlled trials were included in the meta-analysis. Most studies were of low risk of bias. The pooled effect size showed problem-based learning was able to improve nursing students' critical thinking (overall critical thinking scores SMD=0.33, 95%CI=0.13-0.52, P=0.0009), compared with traditional lectures. There was low heterogeneity (overall critical thinking scores I(2)=45%, P=0.07) in the meta-analysis. No significant publication bias was observed regarding overall critical thinking scores (P=0.536). Sensitivity analysis showed that the result of our meta-analysis was reliable. Most

  9. MetaGenyo: a web tool for meta-analysis of genetic association studies.

    Science.gov (United States)

    Martorell-Marugan, Jordi; Toro-Dominguez, Daniel; Alarcon-Riquelme, Marta E; Carmona-Saez, Pedro

    2017-12-16

    Genetic association studies (GAS) aims to evaluate the association between genetic variants and phenotypes. In the last few years, the number of this type of study has increased exponentially, but the results are not always reproducible due to experimental designs, low sample sizes and other methodological errors. In this field, meta-analysis techniques are becoming very popular tools to combine results across studies to increase statistical power and to resolve discrepancies in genetic association studies. A meta-analysis summarizes research findings, increases statistical power and enables the identification of genuine associations between genotypes and phenotypes. Meta-analysis techniques are increasingly used in GAS, but it is also increasing the amount of published meta-analysis containing different errors. Although there are several software packages that implement meta-analysis, none of them are specifically designed for genetic association studies and in most cases their use requires advanced programming or scripting expertise. We have developed MetaGenyo, a web tool for meta-analysis in GAS. MetaGenyo implements a complete and comprehensive workflow that can be executed in an easy-to-use environment without programming knowledge. MetaGenyo has been developed to guide users through the main steps of a GAS meta-analysis, covering Hardy-Weinberg test, statistical association for different genetic models, analysis of heterogeneity, testing for publication bias, subgroup analysis and robustness testing of the results. MetaGenyo is a useful tool to conduct comprehensive genetic association meta-analysis. The application is freely available at http://bioinfo.genyo.es/metagenyo/ .

  10. The effect of heart rate variability biofeedback training on stress and anxiety: a meta-analysis.

    Science.gov (United States)

    Goessl, V C; Curtiss, J E; Hofmann, S G

    2017-11-01

    Some evidence suggests that heart rate variability (HRV) biofeedback might be an effective way to treat anxiety and stress symptoms. To examine the effect of HRV biofeedback on symptoms of anxiety and stress, we conducted a meta-analysis of studies extracted from PubMed, PsycINFO and the Cochrane Library. The search identified 24 studies totaling 484 participants who received HRV biofeedback training for stress and anxiety. We conducted a random-effects meta-analysis. The pre-post within-group effect size (Hedges' g) was 0.81. The between-groups analysis comparing biofeedback to a control condition yielded Hedges' g = 0.83. Moderator analyses revealed that treatment efficacy was not moderated by study year, risk of study bias, percentage of females, number of sessions, or presence of an anxiety disorder. HRV biofeedback training is associated with a large reduction in self-reported stress and anxiety. Although more well-controlled studies are needed, this intervention offers a promising approach for treating stress and anxiety with wearable devices.

  11. [Review of meta-analysis research on exercise in South Korea].

    Science.gov (United States)

    Song, Youngshin; Gang, Moonhee; Kim, Sun Ae; Shin, In Soo

    2014-10-01

    The purpose of this study was to evaluate the quality of meta-analysis regarding exercise using Assessment of Multiple Systematic Reviews (AMSTAR) as well as to compare effect size according to outcomes. Electronic databases including the Korean Studies Information Service System (KISS), the National Assembly Library and the DBpia, HAKJISA and RISS4U for the dates 1990 to January 2014 were searched for 'meta-analysis' and 'exercise' in the fields of medical, nursing, physical therapy and physical exercise in Korea. AMSTAR was scored for quality assessment of the 33 articles included in the study. Data were analyzed using descriptive statistics, t-test, ANOVA and χ²-test. The mean score for AMSTAR evaluations was 4.18 (SD=1.78) and about 67% were classified at the low-quality level and 30% at the moderate-quality level. The scores of quality were statistically different by field of research, number of participants, number of databases, financial support and approval by IRB. The effect size that presented in individual studies were different by type of exercise in the applied intervention. This critical appraisal of meta-analysis published in various field that focused on exercise indicates that a guideline such as the PRISMA checklist should be strongly recommended for optimum reporting of meta-analysis across research fields.

  12. Meta-Analysis With Complex Research Designs: Dealing With Dependence From Multiple Measures and Multiple Group Comparisons

    Science.gov (United States)

    Scammacca, Nancy; Roberts, Greg; Stuebing, Karla K.

    2013-01-01

    Previous research has shown that treating dependent effect sizes as independent inflates the variance of the mean effect size and introduces bias by giving studies with more effect sizes more weight in the meta-analysis. This article summarizes the different approaches to handling dependence that have been advocated by methodologists, some of which are more feasible to implement with education research studies than others. A case study using effect sizes from a recent meta-analysis of reading interventions is presented to compare the results obtained from different approaches to dealing with dependence. Overall, mean effect sizes and variance estimates were found to be similar, but estimates of indexes of heterogeneity varied. Meta-analysts are advised to explore the effect of the method of handling dependence on the heterogeneity estimates before conducting moderator analyses and to choose the approach to dependence that is best suited to their research question and their data set. PMID:25309002

  13. The correlation of social support with mental health: A meta-analysis

    Science.gov (United States)

    Harandi, Tayebeh Fasihi; Taghinasab, Maryam Mohammad; Nayeri, Tayebeh Dehghan

    2017-01-01

    Background and aim Social support is an important factor that can affect mental health. In recent decades, many studies have been done on the impact of social support on mental health. The purpose of the present study is to investigate the effect size of the relationship between social support and mental health in studies in Iran. Methods This meta-analysis was carried out in studies that were performed from 1996 through 2015. Databases included SID and Magiran, the comprehensive portal of human sciences, Noor specialized magazine databases, IRANDOC, Proquest, PubMed, Scopus, ERIC, Iranmedex and Google Scholar. The keywords used to search these websites included “mental health or general health,” and “Iran” and “social support.” In total, 64 studies had inclusion criteria meta-analysis. In order to collect data used from a meta-analysis worksheet that was made by the researcher and for data analysis software, CMA-2 was used. Results The mean of effect size of the 64 studies in the fixed-effect model and random-effect model was obtained respectively as 0.356 and 0.330, which indicated the moderate effect size of social support on mental health. The studies did not have publication bias, and enjoyed a heterogeneous effect size. The target population and social support questionnaire were moderator variables, but sex, sampling method, and mental health questionnaire were not moderator variables. Conclusion Regarding relatively high effect size of the correlation between social support and mental health, it is necessary to predispose higher social support, especially for women, the elderly, patients, workers, and students. PMID:29038699

  14. Meta-Analysis of Explicit Memory Studies in Populations with Intellectual Disability

    Science.gov (United States)

    Lifshitz, Hefziba; Shtein, Sarit; Weiss, Izhak; Vakil, Eli

    2011-01-01

    This meta-analysis combines the effect size (ES) of 40 explicit memory experiments in populations with intellectual disability (ID). Eight meta-analyses were performed, as well as contrast tests between ES. The explicit memory of participants with ID was inferior to that of participants with typical development (TD). Relatively preserved explicit…

  15. Programmed Instruction in Secondary Education: A Meta-Analysis of the Impact of Class Size on Its Effectiveness.

    Science.gov (United States)

    Boden, Andrea; Archwamety, Teara; McFarland, Max

    This review used meta-analytic techniques to integrate findings from 30 independent studies that compared programmed instruction to conventional methods of instruction at the secondary level. The meta-analysis demonstrated that programmed instruction resulted in higher achievement when compared to conventional methods of instruction (average…

  16. The influence of stereotype threat on immigrants: review and meta-analysis

    OpenAIRE

    Appel, Markus; Weber, Silvana; Kronberger, Nicole

    2015-01-01

    In many regions around the world students with certain immigrant backgrounds underachieve in educational settings. This paper provides a review and meta-analysis on one potential source of the immigrant achievement gap: stereotype threat, a situational predicament that may prevent students to perform up to their full abilities. A meta-analysis of 19 experiments suggests an overall mean effect size of 0.63 (random effects model) in support of stereotype threat theory. The results are complemen...

  17. Effectiveness of Mobile Devices on Vocabulary Learning: A Meta-Analysis

    Science.gov (United States)

    Mahdi, Hassan Saleh

    2018-01-01

    Mobile devices are considered as the most widely used information and communication technologies. They have provided great advantages in language learning. This study reports a meta-analysis of the effectiveness of using mobile devices on vocabulary learning. A meta-analysis was conducted on research that compared the outcomes from students…

  18. A random effects meta-analysis model with Box-Cox transformation.

    Science.gov (United States)

    Yamaguchi, Yusuke; Maruo, Kazushi; Partlett, Christopher; Riley, Richard D

    2017-07-19

    In a random effects meta-analysis model, true treatment effects for each study are routinely assumed to follow a normal distribution. However, normality is a restrictive assumption and the misspecification of the random effects distribution may result in a misleading estimate of overall mean for the treatment effect, an inappropriate quantification of heterogeneity across studies and a wrongly symmetric prediction interval. We focus on problems caused by an inappropriate normality assumption of the random effects distribution, and propose a novel random effects meta-analysis model where a Box-Cox transformation is applied to the observed treatment effect estimates. The proposed model aims to normalise an overall distribution of observed treatment effect estimates, which is sum of the within-study sampling distributions and the random effects distribution. When sampling distributions are approximately normal, non-normality in the overall distribution will be mainly due to the random effects distribution, especially when the between-study variation is large relative to the within-study variation. The Box-Cox transformation addresses this flexibly according to the observed departure from normality. We use a Bayesian approach for estimating parameters in the proposed model, and suggest summarising the meta-analysis results by an overall median, an interquartile range and a prediction interval. The model can be applied for any kind of variables once the treatment effect estimate is defined from the variable. A simulation study suggested that when the overall distribution of treatment effect estimates are skewed, the overall mean and conventional I 2 from the normal random effects model could be inappropriate summaries, and the proposed model helped reduce this issue. We illustrated the proposed model using two examples, which revealed some important differences on summary results, heterogeneity measures and prediction intervals from the normal random effects model. The

  19. A random effects meta-analysis model with Box-Cox transformation

    Directory of Open Access Journals (Sweden)

    Yusuke Yamaguchi

    2017-07-01

    Full Text Available Abstract Background In a random effects meta-analysis model, true treatment effects for each study are routinely assumed to follow a normal distribution. However, normality is a restrictive assumption and the misspecification of the random effects distribution may result in a misleading estimate of overall mean for the treatment effect, an inappropriate quantification of heterogeneity across studies and a wrongly symmetric prediction interval. Methods We focus on problems caused by an inappropriate normality assumption of the random effects distribution, and propose a novel random effects meta-analysis model where a Box-Cox transformation is applied to the observed treatment effect estimates. The proposed model aims to normalise an overall distribution of observed treatment effect estimates, which is sum of the within-study sampling distributions and the random effects distribution. When sampling distributions are approximately normal, non-normality in the overall distribution will be mainly due to the random effects distribution, especially when the between-study variation is large relative to the within-study variation. The Box-Cox transformation addresses this flexibly according to the observed departure from normality. We use a Bayesian approach for estimating parameters in the proposed model, and suggest summarising the meta-analysis results by an overall median, an interquartile range and a prediction interval. The model can be applied for any kind of variables once the treatment effect estimate is defined from the variable. Results A simulation study suggested that when the overall distribution of treatment effect estimates are skewed, the overall mean and conventional I 2 from the normal random effects model could be inappropriate summaries, and the proposed model helped reduce this issue. We illustrated the proposed model using two examples, which revealed some important differences on summary results, heterogeneity measures and

  20. Steep discounting of delayed monetary and food rewards in obesity: a meta-analysis.

    Science.gov (United States)

    Amlung, M; Petker, T; Jackson, J; Balodis, I; MacKillop, J

    2016-08-01

    An increasing number of studies have investigated delay discounting (DD) in relation to obesity, but with mixed findings. This meta-analysis synthesized the literature on the relationship between monetary and food DD and obesity, with three objectives: (1) to characterize the relationship between DD and obesity in both case-control comparisons and continuous designs; (2) to examine potential moderators, including case-control v. continuous design, money v. food rewards, sample sex distribution, and sample age (18 years); and (3) to evaluate publication bias. From 134 candidate articles, 39 independent investigations yielded 29 case-control and 30 continuous comparisons (total n = 10 278). Random-effects meta-analysis was conducted using Cohen's d as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger tests, meta-regression of publication year and effect size, and imputation of missing studies. The primary analysis revealed a medium effect size across studies that was highly statistically significant (d = 0.43, p food rewards and child/adolescent samples. Limited evidence of publication bias was present, although the Begg-Mazumdar test and meta-regression suggested a slightly diminishing effect size over time. Steep DD of food and money appears to be a robust feature of obesity that is relatively consistent across the DD assessment methodologies and study designs examined. These findings are discussed in the context of research on DD in drug addiction, the neural bases of DD in obesity, and potential clinical applications.

  1. Mesh size in Lichtenstein repair: a systematic review and meta-analysis to determine the importance of mesh size.

    Science.gov (United States)

    Seker, D; Oztuna, D; Kulacoglu, H; Genc, Y; Akcil, M

    2013-04-01

    Small mesh size has been recognized as one of the factors responsible for recurrence after Lichtenstein hernia repair due to insufficient coverage or mesh shrinkage. The Lichtenstein Hernia Institute recommends a 7 × 15 cm mesh that can be trimmed up to 2 cm from the lateral side. We performed a systematic review to determine surgeons' mesh size preference for the Lichtenstein hernia repair and made a meta-analysis to determine the effect of mesh size, mesh type, and length of follow-up time on recurrence. Two medical databases, PubMed and ISI Web of Science, were systematically searched using the key word "Lichtenstein repair." All full text papers were selected. Publications mentioning mesh size were brought for further analysis. A mesh surface area of 90 cm(2) was accepted as the threshold for defining the mesh as small or large. Also, a subgroup analysis for recurrence pooled proportion according to the mesh size, mesh type, and follow-up period was done. In total, 514 papers were obtained. There were no prospective or retrospective clinical studies comparing mesh size and clinical outcome. A total of 141 papers were duplicated in both databases. As a result, 373 papers were obtained. The full text was available in over 95 % of papers. Only 41 (11.2 %) papers discussed mesh size. In 29 studies, a mesh larger than 90 cm(2) was used. The most frequently preferred commercial mesh size was 7.5 × 15 cm. No papers mentioned the size of the mesh after trimming. There was no information about the relationship between mesh size and patient BMI. The pooled proportion in recurrence for small meshes was 0.0019 (95 % confidence interval: 0.007-0.0036), favoring large meshes to decrease the chance of recurrence. Recurrence becomes more marked when follow-up period is longer than 1 year (p < 0.001). Heavy meshes also decreased recurrence (p = 0.015). This systematic review demonstrates that the size of the mesh used in Lichtenstein hernia repair is rarely

  2. Effects of Parenting Programs on Child Maltreatment Prevention: A Meta-Analysis.

    Science.gov (United States)

    Chen, Mengtong; Chan, Ko Ling

    2016-01-01

    The objective of this study is to evaluate the effectiveness of parenting programs in reducing child maltreatment and modifying associated factors as well as to examine the moderator variables that are linked to program effects. For this meta-analysis, we searched nine electronic databases to identify randomized controlled trials published before September 2013. The effect sizes of various outcomes at different time points were computed. From the 3,578 studies identified, we selected 37 studies for further analysis. The total random effect size was 0.296. Our results showed that parenting programs successfully reduced substantiated and self-reported child maltreatment reports and reduced the potential for child maltreatment. The programs also reduced risk factors and enhanced protective factors associated with child maltreatment. However, the effects of the parenting programs on reducing parental depression and stress were limited. Parenting programs produced positive effects in low-, middle-, and high-income countries and were effective in reducing child maltreatment when applied as primary, secondary, or tertiary child maltreatment intervention. In conclusion, parenting programs are effective public health approaches to reduce child maltreatment. The evidence-based service of parenting programs could be widely adopted in future practice. © The Author(s) 2015.

  3. The effect of loving-kindness meditation on positive emotions: a meta-analytic review

    Directory of Open Access Journals (Sweden)

    Xianglong eZENG

    2015-11-01

    Full Text Available While it has been suggested that loving-kindness meditation (LKM is an effective practice for promoting positive emotions, the empirical evidence in the literature remains unclear. Here, we provide a systematic review of 24 empirical studies (N = 1759 on LKM with self-reported positive emotions. The effect of LKM on positive emotions was estimated with meta-analysis, and the influence of variations across LKM interventions was further explored with subgroup analysis and meta-regression. The meta-analysis showed that (1 medium effect sizes for LKM interventions on daily positive emotions in both wait-list controlled RCTs and non-RCT studies; and (2 small to large effect sizes for the on-going practice of LKM on immediate positive emotions across different comparisons. Further analysis showed that (1 interventions focused on loving-kindness had medium effect size, but interventions focused on compassion showed small effect sizes; (2 the length of interventions and the time spent on meditation did not influence the effect sizes, but the studies without didactic components in interventions had small effect sizes. A few individual studies reported that the nature of positive emotions and individual differences also influenced the results. In sum, LKM practice and interventions are effective in enhancing positive emotions, but more studies are needed to identify the active components of the interventions, to compare different psychological operations, and to explore the applicability in clinical populations.

  4. Mass shootings: a meta-analysis of the dose-response relationship.

    Science.gov (United States)

    Wilson, Laura C

    2014-12-01

    A meta-analysis was conducted to examine the dose-response theory as it relates to posttraumatic stress symptoms (PTSSs) following mass shootings. It was hypothesized that greater exposure to a mass shooting would be associated with greater PTSSs. Trauma exposure in the current study was broadly defined as the extent to which a person experienced or learned about a mass shooting. The meta-analysis identified 11 qualifying studies that included 13 independent effect sizes from a total of 8,047 participants. The overall weighted mean effect size, based on a random effects model, was r = .19, p shooting on the relationship between exposure and PTSSs. Because so few studies satisfied the inclusion criteria, the present study also documents that this area of the literature is underresearched. Copyright © 2014 International Society for Traumatic Stress Studies.

  5. CrossFit Overview: Systematic Review and Meta-analysis.

    Science.gov (United States)

    Claudino, João Gustavo; Gabbett, Tim J; Bourgeois, Frank; Souza, Helton de Sá; Miranda, Rafael Chagas; Mezêncio, Bruno; Soncin, Rafael; Cardoso Filho, Carlos Alberto; Bottaro, Martim; Hernandez, Arnaldo Jose; Amadio, Alberto Carlos; Serrão, Julio Cerca

    2018-02-26

    CrossFit is recognized as one of the fastest growing high-intensity functional training modes in the world. However, scientific data regarding the practice of CrossFit is sparse. Therefore, the objective of this study is to analyze the findings of scientific literature related to CrossFit via systematic review and meta-analysis. Systematic searches of the PubMed, Web of Science, Scopus, Bireme/MedLine, and SciELO online databases were conducted for articles reporting the effects of CrossFit training. The systematic review followed the PRISMA guidelines. The Oxford Levels of Evidence was used for all included articles, and only studies that investigated the effects of CrossFit as a training program were included in the meta-analysis. For the meta-analysis, effect sizes (ESs) with 95% confidence interval (CI) were calculated and heterogeneity was assessed using a random-effects model. Thirty-one articles were included in the systematic review and four were included in the meta-analysis. However, only two studies had a high level of evidence at low risk of bias. Scientific literature related to CrossFit has reported on body composition, psycho-physiological parameters, musculoskeletal injury risk, life and health aspects, and psycho-social behavior. In the meta-analysis, significant results were not found for any variables. The current scientific literature related to CrossFit has few studies with high level of evidence at low risk of bias. However, preliminary data has suggested that CrossFit practice is associated with higher levels of sense of community, satisfaction, and motivation.

  6. A meta-analysis of the effectiveness of individually oriented Cognitive Behavior Therapy (CBT) for severe agressive behavior in adolescents

    NARCIS (Netherlands)

    Hoogsteder, L.M; Stams, G.J.J.M.; Figge, M.A.; Changoe, K.; van Horn, J.; Hendriks, J.; Wissink, I.B.

    2015-01-01

    This meta-analysis, including six studies (13 effect sizes) and 164 adolescents, examined the effectiveness of individually oriented treatment (which means that the intervention contained at least an individual component, possibly in combination with group and/or family therapy) with CBT-elements

  7. A meta-analysis of the effectiveness of individually oriented Cognitive Behavioral Treatment (CBT) for severe agressive behavior in adolescents

    NARCIS (Netherlands)

    Hoogsteder, L.M.; Stams, G.J.J.M.; Figge, M.A.; Changoe, K.; van Horn, J.E.; Hendriks, J.; Wissink, I.B.

    2015-01-01

    This meta-analysis, including six studies (13 effect sizes) and 164 adolescents, examined the effectiveness of individually oriented treatment (which means that the intervention contained at least an individual component, possibly in combination with group and/or family therapy) with CBT-elements

  8. Autogenic training: a meta-analysis of clinical outcome studies.

    Science.gov (United States)

    Stetter, Friedhelm; Kupper, Sirko

    2002-03-01

    Autogenic training (AT) is a self-relaxation procedure by which a psychophysiological determined relaxation response is elicited. A meta-analysis was performed to evaluate the clinical effectiveness of AT. Seventy-three controlled outcome studies were found (published 1952-99). Sixty studies (35 randomized controlled trials [RCT]) qualified for inclusion in the meta-analysis. Medium-to-large effect sizes (ES) occurred for pre-post comparisons of disease-specific AT-effects, with the RCTs showing larger ES. When AT was compared to real control conditions, medium ES were found. Comparisons of AT versus other psychological treatment mostly resulted in no effects or small negative ES. This pattern of results was stable at follow-up. Unspecific AT-effects (i.e., effects on mood, cognitive performance, quality of life, and physiological variables) tended to be even larger than main effects. Separate meta-analyses for different disorders revealed a significant reduction of the heterogeneity of ES. Positive effects (medium range) of AT and of AT versus control in the meta-analysis of at least 3 studies were found for tension headache/migraine, mild-to-moderate essential hypertension, coronary heart disease, asthma bronchiale, somatoform pain disorder (unspecified type), Raynaud's disease, anxiety disorders, mild-to-moderate depression/dysthymia, and functional sleep disorders.

  9. Moral development and recidivism: a meta-analysis.

    Science.gov (United States)

    Van Vugt, Eveline; Gibbs, John; Stams, Geert Jan; Bijleveld, Catrien; Hendriks, Jan; van der Laan, Peter

    2011-12-01

    A meta-analysis of 19 studies (N = 15,992 offenders) showed a significant inverse relation between more mature moral development and recidivism. Moderator analyses revealed a larger effect size for moral cognition (r = .20) than for moral emotion (r = .11). Effect sizes for production measures (r = .57) were much larger than for recognition measures (r = .16) and unstructured (clinical) judgment (r = .10). Larger effect sizes were found for female delinquents (r = .32) than for male delinquents (r = .21). Only small differences in effect sizes were found between juvenile delinquents (r = .10) and adult delinquents (r = .16). Finally, self-report measures of recidivism revealed much larger effect sizes (r = .32) than official reports of recidivism (r = .09). The discussion focuses on the theoretical and practical meaning of the magnitude of the effect size for the relation between moral development and recidivism.

  10. Effectiveness of Social Media-based Interventions on Weight-related Behaviors and Body Weight Status: Review and Meta-analysis.

    Science.gov (United States)

    An, Ruopeng; Ji, Mengmeng; Zhang, Sheng

    2017-11-01

    We reviewed scientific literature regarding the effectiveness of social media-based interventions about weight-related behaviors and body weight status. A keyword search were performed in May 2017 in the Clinical-Trials.gov, Cochrane Library, PsycINFO, PubMed, and Web of Science databases. We conducted a meta-analysis to estimate the pooled effect size of social media-based interventions on weight-related outcome measures. We identified 22 interventions from the keyword and reference search, including 12 randomized controlled trials, 6 pre-post studies and 3 cohort studies conducted in 9 countries during 2010-2016. The majority (N = 17) used Facebook, followed by Twitter (N = 4) and Instagram (N = 1). Intervention durations averaged 17.8 weeks with a mean sample size of 69. The meta-analysis showed that social media-based interventions were associated with a statistically significant, but clinically modest reduction of body weight by 1.01 kg, body mass index by 0.92 kg/m2, and waist circumstance by 2.65 cm, and an increase of daily number of steps taken by 1530. In the meta-regression there was no doseresponse effect with respect to intervention duration. The boom of social media provides an unprecedented opportunity to implement health promotion programs. Future interventions should make efforts to improve intervention scalability and effectiveness.

  11. Effect of aquatic exercise on fibromyalgia symptoms: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Diana Villalobos Blanco

    2010-12-01

    Full Text Available Fibromyalgia (FM symptoms cause a decline in the quality of life of people who suffer it, ranging from mild to severe; for that reason diverse therapies have been studied to lessen the health consequences of this syndrome. Aquatic exercises have shown positive results in many studies, setting the objective of performing a meta-analysis of the characteristics of this type of exercise and its association with symptoms caused by fibromyalgia. We included 16 studies (only pure experimental studies published between 1998 and 2008, from which we calculated a total of 196 effect sizes. An initial analysis compared the type of physical activity and then analyzed the moderating variables including studies that used only water activities. When analyzing the type of activity performed, the only one showing significant differences when compared to the control group was the one executed in an aquatic environment. From this subset, significant effect sizes were found at all ages studied, years of suffering the disease, exercise frequency, intensity, size of group, number of sessions, symptoms and all the components of physical fitness analyzed. In general, the activity is recommended to be performed in large groups, encouraging social ties, with a frequency of three sessions of 60 minutes per week, regardless of the intensity.

  12. A Meta-Analysis of the Relation between Creative Self-Efficacy and Different Creativity Measurements

    Science.gov (United States)

    Haase, Jennifer; Hoff, Eva V.; Hanel, Paul H. P.; Innes-Ker, Åse

    2018-01-01

    This meta-analysis investigated the relations between creative self-efficacy (CSE) and creativity measures and hypothesized that self-assessed questionnaires would have a different relation to self-efficacy beliefs compared to other creativity tests. The meta-analysis synthesized 60 effect sizes from 41 papers (overall N = 17226). Taken as a…

  13. Mobile technology boosts the effectiveness of psychotherapy and behavioral interventions: a meta-analysis.

    Science.gov (United States)

    Lindhiem, Oliver; Bennett, Charles B; Rosen, Dana; Silk, Jennifer

    2015-11-01

    We conducted a meta-analysis on the effects of mobile technology on treatment outcome for psychotherapy and other behavioral interventions. Our search of the literature resulted in 26 empirical articles describing 25 clinical trials testing the benefits of smartphone applications, personal digital assistants (PDAs), or text messaging systems either to supplement treatment or substitute for direct contact with a clinician. Overall, mobile technology use was associated with superior treatment outcome across all study designs and control conditions, effect size (ES) = .34, p mobile technology using a rigorous "Treatment" versus "Treatment + Mobile" design, effect sizes were only slightly more modest (ES = .27) and still significant (p mobile technology for the delivery of psychotherapy and other behavioral interventions. © The Author(s) 2015.

  14. Effects of augmentative and alternative communication on challenging behavior: a meta-analysis.

    Science.gov (United States)

    Walker, Virginia L; Snell, Martha E

    2013-06-01

    The purposes of this review were to (a) use meta-analytic procedures to examine the effectiveness of single-case AAC intervention research on challenging behaviors exhibited by individuals with disabilities, (b) identify study characteristics that moderate intervention effects, and (c) evaluate the quality of research. The authors provided inferential and descriptive analyses of 54 studies representing 111 participants and estimated effect sizes using the Nonoverlap of All Pairs (NAP) method. Overall, AAC interventions were found to be equally effective across a broad spectrum of participants and interventions. AAC interventions were more effective with younger children than with adults. Interventions in which functional behavior assessments (FBA) were used had significantly larger effect sizes than those that did not use FBAs. Further, functional communication training interventions resulted in larger effect sizes than Picture Exchange Communication System interventions. Descriptive analysis revealed that (a) interventions often occurred in atypical environments (e.g., therapy room, experimental room) and with atypical interventionists (e.g., therapists, researchers), and (b) numerous studies did not exhibit quality characteristics of single-case research.

  15. Mismatch Negativity in Han Chinese Patients with Schizophrenia: A Meta-Analysis.

    Science.gov (United States)

    Xiong, Yanbing; Ll, Xianbin; Zhao, Lei; Wang, Chuanyue

    2017-10-25

    Previous meta-analysis revealed that mismatch negativity(MMN) amplitude decreased in patients with schizophrenia compared with healthy controls (Cohen's d, d about 1), leading to the possibility of mismatch negativity being used as a biomarker for schizophrenia. However, it is unknown whether MMN is reliably changed in Chinese patients. It is necessary to carry out a meta-analysis on MMN of Han Chinese patients with schizophrenia. To investigate whether MMN could be used as a biomarker for Han Chinese patients with schizophrenia. A literature search was conducted to identify clinical trials on MMN in Han Chinese schizophrenia patients published before May 8, 2017, by searching the Chinese language databases CNKI, WanFang Data, VIP Data and PubMed. The effects of MMN deficits were evaluated for MMN amplitude by calculating standard mean difference (SMDs) between schizophrenia patient groups and healthy control groups. A total of 11 studies were included in the analysis. The total quality of all the studies were more than 6 as evaluated by Newcastle-Ottawa Scale (NOS). Meta-analysis of data from these studies had a pooled sample of 432 patients with schizophrenia and 392 healthy controls. There exists significant MMN deficit in schizophrenia patients compared to healthy controls (Cohen's d =1.004). When studies were excluded due to heterogeneity, the pooled effect size of the MMN differences between the patient group and healthy controls dropped to 0.79 (Cohen's d =0.79). Subgroup analysis showed that MMN amplitude deficits of schizophrenia over three years had the pooled effect size of 0.95, and less than three years had the pooled effect size of 0.77. Publication bias conducted via Egger regression test ( t = 1.83; p = 0.101), suggested that there was no publication bias. The effect size of MMN amplitude between Chinese patients with schizophrenia and healthy controls is consistent with other meta-analyses published on this topic, suggesting that Han Chinese

  16. Relaxation training for anxiety: a ten-years systematic review with meta-analysis.

    Science.gov (United States)

    Manzoni, Gian Mauro; Pagnini, Francesco; Castelnuovo, Gianluca; Molinari, Enrico

    2008-06-02

    Relaxation training is a common treatment for anxiety problems. Lacking is a recent quantitative meta-analysis that enhances understanding of the variability and clinical significance of anxiety reduction outcomes after relaxation treatment. All studies (1997-2007), both RCT, observational and without control group, evaluating the efficacy of relaxation training (Jacobson's progressive relaxation, autogenic training, applied relaxation and meditation) for anxiety problems and disorders were identified by comprehensive electronic searches with Pubmed, Psychinfo and Cochrane Registers, by checking references of relevant studies and of other reviews. Our primary outcome was anxiety measured with psychometric questionnaires. Meta-analysis was undertaken synthesizing the data from all trials, distinguishing within and between effect sizes. 27 studies qualified for the inclusion in the meta-analysis. As hypothesized, relaxation training showed a medium-large effect size in the treatment of anxiety. Cohen's d was .57 (95% CI: .52 to .68) in the within analysis and .51 (95% CI: .46 to .634) in the between group analysis. Efficacy was higher for meditation, among volunteers and for longer treatments. Implications and limitations are discussed. The results show consistent and significant efficacy of relaxation training in reducing anxiety. This meta-analysis extends the existing literature through facilitation of a better understanding of the variability and clinical significance of anxiety improvement subsequent to relaxation training.

  17. "Are cognitive interventions effective in Alzheimer's disease? A controlled meta- analysis of the effects of bias": Correction to Oltra-Cucarella et al. (2016).

    Science.gov (United States)

    2016-07-01

    Reports an error in "Are Cognitive Interventions Effective in Alzheimer's Disease? A Controlled Meta-Analysis of the Effects of Bias" by Javier Oltra-Cucarella, Rubén Pérez-Elvira, Raul Espert and Anita Sohn McCormick (Neuropsychology, Advanced Online Publication, Apr 7, 2016, np). In the article the first sentence of the third paragraph of the Source of bias subsection in the Statistical Analysis subsection of the Correlational Meta-Analysis section should read "For the control condition bias, three comparison groups were differentiated: (a) a structured cognitive intervention, (b) a placebo control condition, and (c) a pharma control condition without cognitive intervention or no treatment at all." (The following abstract of the original article appeared in record 2016-16656-001.) There is limited evidence about the efficacy of cognitive interventions for Alzheimer's disease (AD). However, aside from the methodological quality of the studies analyzed, the methodology used in previous meta-analyses is itself a risk of bias as different types of effect sizes (ESs) were calculated and combined. This study aimed at examining the results of nonpharmacological interventions for AD with an adequate control of statistical methods and to demonstrate a different approach to meta-analysis. ESs were calculated with the independent groups pre/post design. Average ESs for separate outcomes were calculated and moderator analyses were performed so as to offer an overview of the effects of bias. Eighty-seven outcomes from 19 studies (n = 812) were meta-analyzed. ESs were small on average for cognitive and functional outcomes after intervention. Moderator analyses showed no effect of control of bias, although ESs were different from zero only in some circumstances (e.g., memory outcomes in randomized studies). Cognitive interventions showed no more efficacy than placebo interventions, and functional ESs were consistently low across conditions. cognitive interventions delivered

  18. Marital status integration and suicide: A meta-analysis and meta-regression.

    Science.gov (United States)

    Kyung-Sook, Woo; SangSoo, Shin; Sangjin, Shin; Young-Jeon, Shin

    2018-01-01

    Marital status is an index of the phenomenon of social integration within social structures and has long been identified as an important predictor suicide. However, previous meta-analyses have focused only on a particular marital status, or not sufficiently explored moderators. A meta-analysis of observational studies was conducted to explore the relationships between marital status and suicide and to understand the important moderating factors in this association. Electronic databases were searched to identify studies conducted between January 1, 2000 and June 30, 2016. We performed a meta-analysis, subgroup analysis, and meta-regression of 170 suicide risk estimates from 36 publications. Using random effects model with adjustment for covariates, the study found that the suicide risk for non-married versus married was OR = 1.92 (95% CI: 1.75-2.12). The suicide risk was higher for non-married individuals aged analysis by gender, non-married men exhibited a greater risk of suicide than their married counterparts in all sub-analyses, but women aged 65 years or older showed no significant association between marital status and suicide. The suicide risk in divorced individuals was higher than for non-married individuals in both men and women. The meta-regression showed that gender, age, and sample size affected between-study variation. The results of the study indicated that non-married individuals have an aggregate higher suicide risk than married ones. In addition, gender and age were confirmed as important moderating factors in the relationship between marital status and suicide. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Gardening is beneficial for health: A meta-analysis.

    Science.gov (United States)

    Soga, Masashi; Gaston, Kevin J; Yamaura, Yuichi

    2017-03-01

    There is increasing evidence that gardening provides substantial human health benefits. However, no formal statistical assessment has been conducted to test this assertion. Here, we present the results of a meta-analysis of research examining the effects of gardening, including horticultural therapy, on health. We performed a literature search to collect studies that compared health outcomes in control (before participating in gardening or non-gardeners) and treatment groups (after participating in gardening or gardeners) in January 2016. The mean difference in health outcomes between the two groups was calculated for each study, and then the weighted effect size determined both across all and sets of subgroup studies. Twenty-two case studies (published after 2001) were included in the meta-analysis, which comprised 76 comparisons between control and treatment groups. Most studies came from the United States, followed by Europe, Asia, and the Middle East. Studies reported a wide range of health outcomes, such as reductions in depression, anxiety, and body mass index, as well as increases in life satisfaction, quality of life, and sense of community. Meta-analytic estimates showed a significant positive effect of gardening on the health outcomes both for all and sets of subgroup studies, whilst effect sizes differed among eight subgroups. Although Egger's test indicated the presence of publication bias, significant positive effects of gardening remained after adjusting for this using trim and fill analysis. This study has provided robust evidence for the positive effects of gardening on health. A regular dose of gardening can improve public health.

  20. Gardening is beneficial for health: A meta-analysis

    Directory of Open Access Journals (Sweden)

    Masashi Soga

    2017-03-01

    Full Text Available There is increasing evidence that gardening provides substantial human health benefits. However, no formal statistical assessment has been conducted to test this assertion. Here, we present the results of a meta-analysis of research examining the effects of gardening, including horticultural therapy, on health. We performed a literature search to collect studies that compared health outcomes in control (before participating in gardening or non-gardeners and treatment groups (after participating in gardening or gardeners in January 2016. The mean difference in health outcomes between the two groups was calculated for each study, and then the weighted effect size determined both across all and sets of subgroup studies. Twenty-two case studies (published after 2001 were included in the meta-analysis, which comprised 76 comparisons between control and treatment groups. Most studies came from the United States, followed by Europe, Asia, and the Middle East. Studies reported a wide range of health outcomes, such as reductions in depression, anxiety, and body mass index, as well as increases in life satisfaction, quality of life, and sense of community. Meta-analytic estimates showed a significant positive effect of gardening on the health outcomes both for all and sets of subgroup studies, whilst effect sizes differed among eight subgroups. Although Egger's test indicated the presence of publication bias, significant positive effects of gardening remained after adjusting for this using trim and fill analysis. This study has provided robust evidence for the positive effects of gardening on health. A regular dose of gardening can improve public health.

  1. The Effectiveness of Self-Regulated Learning Scaffolds on Academic Performance in Computer-Based Learning Environments: A Meta-Analysis

    Science.gov (United States)

    Zheng, Lanqin

    2016-01-01

    This meta-analysis examined research on the effects of self-regulated learning scaffolds on academic performance in computer-based learning environments from 2004 to 2015. A total of 29 articles met inclusion criteria and were included in the final analysis with a total sample size of 2,648 students. Moderator analyses were performed using a…

  2. Use of meta-analysis to combine candidate gene association studies: application to study the relationship between the ESR PvuII polymorphism and sow litter size

    Directory of Open Access Journals (Sweden)

    Alfonso Leopoldo

    2005-07-01

    Full Text Available Abstract This article investigates the application of meta-analysis on livestock candidate gene effects. The PvuII polymorphism of the ESR gene is used as an example. The association among ESR PvuII alleles with the number of piglets born alive and total born in the first (NBA1, TNB1 and later parities (NBA, TNB is reviewed by conducting a meta-analysis of 15 published studies including 9329 sows. Under a fixed effects model, litter size values were significantly lower in the "AA" genotype groups when compared with "AB" and "BB" homozygotes. Under the random effects model, the results were similar although differences between "AA" and "AB" genotype groups were not clearly significant for NBA and TNB. Nevertheless, the most noticeable result was the high and significant heterogeneity estimated among studies. This heterogeneity could be assigned to error sampling, genotype by environment interaction, linkage or epistasis, as referred to in the literature, but also to the hypothesis of population admixture/stratification. It is concluded that meta-analysis can be considered as a helpful analytical tool to synthesise and discuss livestock candidate gene effects. The main difficulty found was the insufficient information on the standard errors of the estimated genotype effects in several publications. Consequently, the convenience of publishing the standard errors or the concrete P-values instead of the test significance level should be recommended to guarantee the quality of candidate gene effect meta-analyses.

  3. The effects of resistance training interventions on vertical jump performance in basketball players: a meta-analysis.

    Science.gov (United States)

    Sperlich, Paula F; Behringer, Michael; Mester, Joachim

    2016-01-01

    Vertical jump performance is one of the key factors in basketball. In order to determine the effectiveness of previously published interventions and their influencing factors we performed a meta-analysis. A computerized search was conducted using the databases PubMed (1966), Web of Science (1900), SPORTDiscus™ (1975),Medline (1966) and SportPilot (2008). Studies involving healthy male or female basketball players at any age and performance level were included. All trials had to investigate the benefits of resistance training programs on jumping performance in basketball players and provide a control group. The effect size (ES) was computed and the relationship between ESs and continuous variables was examined by meta-regressions, whereas subgroup meta-analyses and z-tests were used to assess the impact of categorical moderator variables. The meta-analysis included 14 studies with 20 subgroups and a total of 37 outcomes. A total of 399 participants were examined, N.=157 served as control and N.=242 took part in particular training interventions. The overall weighted ES of 0.78 (95% CI 0.41, 1.15) was significantly greater than zero (Ptraining effect. However, positive correlations were found for training duration (r=0.68; P=0.02). The present meta-analysis demonstrates that resistance training throughout the year, using bodyweight or external weight, significantly improves vertical jump performance in healthy basketball players. Since vertical jump improvements were independent of intervention period but dependent on the duration of each individual training session the total training amount should be based on longer training sessions.

  4. The Effects of Massage Therapy on Pain and Anxiety after Surgery: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Kukimoto, Yukiko; Ooe, Noriko; Ideguchi, Norio

    2017-12-01

    Pain management is critical for patients after surgery, but current pain management methods are not always adequate. Massage therapy may be a therapeutic complementary therapy for pain. Many researchers have investigated the effects of massage therapy on post-operative pain, but there have been no systematic reviews and meta-analysis of its efficacy for post-operative patients. Our objective was to assess the effects of massage therapy on pain management among post-operative patients by conducting a systematic review and meta-analysis. The databases searched included MEDLINE, CINAHL, and the Cochrane Library's CENTRAL. To assess the effects of massage therapy on post-operative pain and anxiety, we performed a meta-analysis and calculated standardized mean difference with 95% CIs (Confidential Intervals) as a summary effect. Ten randomized controlled trials were selected (total sample size = 1,157). Meta-analysis was conducted using subgroup analysis. The effect of single dosage massage therapy on post-operative pain showed significant improvement (-0.49; 95% confidence intervals -0.64, -0.34; p < .00001) and low heterogeneity (p = .39, I 2 = 4%), sternal incisions showed significant improvement in pain (-0.68; -0.91, -0.46; p< .00001) and low heterogeneity (p = .76, I 2 = 0%). The anxiety subgroups showed substantial heterogeneity. The findings of this study revealed that massage therapy may alleviate post-operative pain, although there are limits on generalization of these findings due to low methodological quality in the reviewed studies. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  5. Teaching meta-analysis using MetaLight

    Directory of Open Access Journals (Sweden)

    Thomas James

    2012-10-01

    Full Text Available Abstract Background Meta-analysis is a statistical method for combining the results of primary studies. It is often used in systematic reviews and is increasingly a method and topic that appears in student dissertations. MetaLight is a freely available software application that runs simple meta-analyses and contains specific functionality to facilitate the teaching and learning of meta-analysis. While there are many courses and resources for meta-analysis available and numerous software applications to run meta-analyses, there are few pieces of software which are aimed specifically at helping those teaching and learning meta-analysis. Valuable teaching time can be spent learning the mechanics of a new software application, rather than on the principles and practices of meta-analysis. Findings We discuss ways in which the MetaLight tool can be used to present some of the main issues involved in undertaking and interpreting a meta-analysis. Conclusions While there are many software tools available for conducting meta-analysis, in the context of a teaching programme such software can require expenditure both in terms of money and in terms of the time it takes to learn how to use it. MetaLight was developed specifically as a tool to facilitate the teaching and learning of meta-analysis and we have presented here some of the ways it might be used in a training situation.

  6. L2 Reading Comprehension and Its Correlates: A Meta-Analysis

    Science.gov (United States)

    Jeon, Eun Hee; Yamashita, Junko

    2014-01-01

    The present meta-analysis examined the overall average correlation (weighted for sample size and corrected for measurement error) between passage-level second language (L2) reading comprehension and 10 key reading component variables investigated in the research domain. Four high-evidence correlates (with 18 or more accumulated effect sizes: L2…

  7. A Bayesian approach to meta-analysis of plant pathology studies.

    Science.gov (United States)

    Mila, A L; Ngugi, H K

    2011-01-01

    Bayesian statistical methods are used for meta-analysis in many disciplines, including medicine, molecular biology, and engineering, but have not yet been applied for quantitative synthesis of plant pathology studies. In this paper, we illustrate the key concepts of Bayesian statistics and outline the differences between Bayesian and classical (frequentist) methods in the way parameters describing population attributes are considered. We then describe a Bayesian approach to meta-analysis and present a plant pathological example based on studies evaluating the efficacy of plant protection products that induce systemic acquired resistance for the management of fire blight of apple. In a simple random-effects model assuming a normal distribution of effect sizes and no prior information (i.e., a noninformative prior), the results of the Bayesian meta-analysis are similar to those obtained with classical methods. Implementing the same model with a Student's t distribution and a noninformative prior for the effect sizes, instead of a normal distribution, yields similar results for all but acibenzolar-S-methyl (Actigard) which was evaluated only in seven studies in this example. Whereas both the classical (P = 0.28) and the Bayesian analysis with a noninformative prior (95% credibility interval [CRI] for the log response ratio: -0.63 to 0.08) indicate a nonsignificant effect for Actigard, specifying a t distribution resulted in a significant, albeit variable, effect for this product (CRI: -0.73 to -0.10). These results confirm the sensitivity of the analytical outcome (i.e., the posterior distribution) to the choice of prior in Bayesian meta-analyses involving a limited number of studies. We review some pertinent literature on more advanced topics, including modeling of among-study heterogeneity, publication bias, analyses involving a limited number of studies, and methods for dealing with missing data, and show how these issues can be approached in a Bayesian framework

  8. MetaSeq: privacy preserving meta-analysis of sequencing-based association studies.

    Science.gov (United States)

    Singh, Angad Pal; Zafer, Samreen; Pe'er, Itsik

    2013-01-01

    Human genetics recently transitioned from GWAS to studies based on NGS data. For GWAS, small effects dictated large sample sizes, typically made possible through meta-analysis by exchanging summary statistics across consortia. NGS studies groupwise-test for association of multiple potentially-causal alleles along each gene. They are subject to similar power constraints and therefore likely to resort to meta-analysis as well. The problem arises when considering privacy of the genetic information during the data-exchange process. Many scoring schemes for NGS association rely on the frequency of each variant thus requiring the exchange of identity of the sequenced variant. As such variants are often rare, potentially revealing the identity of their carriers and jeopardizing privacy. We have thus developed MetaSeq, a protocol for meta-analysis of genome-wide sequencing data by multiple collaborating parties, scoring association for rare variants pooled per gene across all parties. We tackle the challenge of tallying frequency counts of rare, sequenced alleles, for metaanalysis of sequencing data without disclosing the allele identity and counts, thereby protecting sample identity. This apparent paradoxical exchange of information is achieved through cryptographic means. The key idea is that parties encrypt identity of genes and variants. When they transfer information about frequency counts in cases and controls, the exchanged data does not convey the identity of a mutation and therefore does not expose carrier identity. The exchange relies on a 3rd party, trusted to follow the protocol although not trusted to learn about the raw data. We show applicability of this method to publicly available exome-sequencing data from multiple studies, simulating phenotypic information for powerful meta-analysis. The MetaSeq software is publicly available as open source.

  9. Meta-analysis of SNPs involved in variance heterogeneity using Levene's test for equal variances

    Science.gov (United States)

    Deng, Wei Q; Asma, Senay; Paré, Guillaume

    2014-01-01

    Meta-analysis is a commonly used approach to increase the sample size for genome-wide association searches when individual studies are otherwise underpowered. Here, we present a meta-analysis procedure to estimate the heterogeneity of the quantitative trait variance attributable to genetic variants using Levene's test without needing to exchange individual-level data. The meta-analysis of Levene's test offers the opportunity to combine the considerable sample size of a genome-wide meta-analysis to identify the genetic basis of phenotypic variability and to prioritize single-nucleotide polymorphisms (SNPs) for gene–gene and gene–environment interactions. The use of Levene's test has several advantages, including robustness to departure from the normality assumption, freedom from the influence of the main effects of SNPs, and no assumption of an additive genetic model. We conducted a meta-analysis of the log-transformed body mass index of 5892 individuals and identified a variant with a highly suggestive Levene's test P-value of 4.28E-06 near the NEGR1 locus known to be associated with extreme obesity. PMID:23921533

  10. A Meta-Analysis of Resistance Training in Female Youth: Its Effect on Muscular Strength, and Shortcomings in the Literature.

    Science.gov (United States)

    Moran, Jason; Sandercock, Gavin; Ramirez-Campillo, Rodrigo; Clark, Cain C T; Fernandes, John F T; Drury, Benjamin

    2018-07-01

    Resistance training is an effective way to enhance strength in female youth but, to date, no researcher has meta-analysed its effect on muscular strength in that population. This meta-analysis characterised female youths' adaptability to resistance training (RT). A second objective was to highlight the limitations of the body of literature with a view to informing future research. Google Scholar, PubMed, Web of Science. Resistance training interventions in healthy females with a mean age between 8 and 18 years. Programmes of between 4 and 16 weeks' duration that included a control group. The inverse-variance random effects model for meta-analyses was used because it allocates a proportionate weight to trials based on the size of their individual standard errors and facilitates analysis whilst accounting for heterogeneity across studies. Effect sizes, calculated from a measure of muscular strength, are represented by the standardised mean difference and are presented alongside 95% confidence intervals. The magnitude of the main effect was 'small' (0.54, 95% confidence interval: 0.23-0.85). Effect sizes were larger in older (> 15 years; ES = 0.72 [0.23-1.21] vs. 0.38 [- 0.02-0.79]), taller (> 163 cm; ES = 0.67 [0.20-1.13] vs. 0.55 [0.08-1.02]) and heavier (< 54 kg; ES = 0.67 [0.30-1.03] vs. 0.53 [- 0.00-1.06]) participants. Resistance training is effective in female youth. These findings can be used to inform the prescription of RT in female youth.

  11. Measuring the environmental effects of organic farming: A meta-analysis of structural variables in empirical research.

    Science.gov (United States)

    Lee, Ki Song; Choe, Young Chan; Park, Sung Hee

    2015-10-01

    This study examined the structural variables affecting the environmental effects of organic farming compared to those of conventional farming. A meta-analysis based on 107 studies and 360 observations published from 1977 to 2012 compared energy efficiency (EE) and greenhouse gas emissions (GHGE) for organic and conventional farming. The meta-analysis systematically analyzed the results of earlier comparative studies and used logistic regression to identify the structural variables that contributed to differences in the effects of organic and conventional farming on the environment. The statistical evidence identified characteristics that differentiated the environmental effects of organic and conventional farming, which is controversial. The results indicated that data sources, sample size and product type significantly affected EE, whereas product type, cropping pattern and measurement unit significantly affected the GHGE of organic farming compared to conventional farming. Superior effects of organic farming on the environment were more likely to appear for larger samples, primary data rather than secondary data, monocropping rather than multicropping, and crops other than fruits and vegetables. The environmental effects of organic farming were not affected by the study period, geographic location, farm size, cropping pattern, or measurement method. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. A Meta-Analysis of Treatment Interventions for Internet Addiction Among Korean Adolescents.

    Science.gov (United States)

    Chun, JongSerl; Shim, HaiSun; Kim, Soyoun

    2017-04-01

    This study comprehensively examined the effects of treatment interventions for Internet addiction among adolescents in South Korea through a meta-analysis. We analyzed 70 domestic master's theses and journal articles that reported on controlled studies and involved pre- and post-test analyses in the design. The dates of these publications fall between 2000 and 2015. The total effect size, calculated by random-effect analysis (g), revealed that interventions for the treatment of Internet addiction were effective (ES = 1.838). Meta-ANOVAs revealed differences between groups based on a theoretical model, intervention group size, and intervention duration. Integrative therapy produced larger effect sizes (ES = 2.794) compared to other treatment models such as cognitive behavioral therapy and reality therapy. Effect sizes for interventions, including nine to 12 people (ES = 2.178), were larger than those of interventions including more or fewer participants. Finally, treatment interventions that lasted 8 or more weeks revealed larger effect sizes (ES = 2.294) compared to shorter interventions. The study findings suggest directions for the development and effective operation of future Internet addiction interventions among Korean adolescents. Increasing the effectiveness of these interventions requires an integrative theoretical model, an intervention group size of nine to 12 participants, and a long-term intervention.

  13. Gender role affects experimental pain responses: a systematic review with meta-analysis.

    Science.gov (United States)

    Alabas, O A; Tashani, O A; Tabasam, G; Johnson, M I

    2012-10-01

    Gender role refers to the culturally and socially constructed meanings that describe how women and men should behave in certain situations according to feminine and masculine roles learned throughout life. The aim of this meta-analysis was to evaluate the relationship between gender role and experimental pain responses in healthy human participants. We searched computerized databases for studies published between January 1950 and May 2011 that had measured gender role in healthy human adults and pain response to noxious stimuli. Studies were entered into a meta-analysis if they calculated a correlation coefficient (r) for gender role and experimental pain. Searches yielded 4465 'hits' and 13 studies were eligible for review. Sample sizes were 67-235 participants and the proportion of female participants was 45-67%. Eight types of gender role instrument were used. Meta-analysis of six studies (406 men and 539 women) found a significant positive correlation between masculine and feminine personality traits and pain threshold and tolerance, with a small effect size (r = 0.17, p = 0.01). Meta-analysis of four studies (263 men and 297 women) found a significant negative correlation between gender stereotypes specific to pain and pain threshold and tolerance, with a moderate effect size (r = -0.41, p Gender stereotypes specific to pain scales showed stronger associations with sex differences in pain sensitivity response than masculine and feminine personality trait scales. © 2012 European Federation of International Association for the Study of Pain Chapters.

  14. Can statistic adjustment of OR minimize the potential confounding bias for meta-analysis of case-control study? A secondary data analysis.

    Science.gov (United States)

    Liu, Tianyi; Nie, Xiaolu; Wu, Zehao; Zhang, Ying; Feng, Guoshuang; Cai, Siyu; Lv, Yaqi; Peng, Xiaoxia

    2017-12-29

    Different confounder adjustment strategies were used to estimate odds ratios (ORs) in case-control study, i.e. how many confounders original studies adjusted and what the variables are. This secondary data analysis is aimed to detect whether there are potential biases caused by difference of confounding factor adjustment strategies in case-control study, and whether such bias would impact the summary effect size of meta-analysis. We included all meta-analyses that focused on the association between breast cancer and passive smoking among non-smoking women, as well as each original case-control studies included in these meta-analyses. The relative deviations (RDs) of each original study were calculated to detect how magnitude the adjustment would impact the estimation of ORs, compared with crude ORs. At the same time, a scatter diagram was sketched to describe the distribution of adjusted ORs with different number of adjusted confounders. Substantial inconsistency existed in meta-analysis of case-control studies, which would influence the precision of the summary effect size. First, mixed unadjusted and adjusted ORs were used to combine individual OR in majority of meta-analysis. Second, original studies with different adjustment strategies of confounders were combined, i.e. the number of adjusted confounders and different factors being adjusted in each original study. Third, adjustment did not make the effect size of original studies trend to constringency, which suggested that model fitting might have failed to correct the systematic error caused by confounding. The heterogeneity of confounder adjustment strategies in case-control studies may lead to further bias for summary effect size in meta-analyses, especially for weak or medium associations so that the direction of causal inference would be even reversed. Therefore, further methodological researches are needed, referring to the assessment of confounder adjustment strategies, as well as how to take this kind

  15. Effects of the Use of High-Fidelity Human Simulation in Nursing Education: A Meta-Analysis.

    Science.gov (United States)

    Lee, Jin; Oh, Pok-Ja

    2015-09-01

    This study was conducted to evaluate the effects of high-fidelity human simulation (HFHS) on cognitive, affective, and psychomotor outcomes of learning. PubMed, Cochrane Library, EMBASE, CINAHL, and Korean databases were searched. The RevMan program was used for analysis. A meta-analysis was conducted of 26 controlled trials, with a total of 2,031 nursing students. The use of HFHS tended to have beneficial effects on cognitive and psychomotor domains of learning. In analysis of cognitive outcomes, the weighted average effect size across studies was -0.97 for problem-solving competency, -0.67 for critical thinking, and -2.15 for clinical judgment. The effect size for clinical competence of the psychomotor domain was -0.81. Use of HFHS might positively impact a high level of cognitive skill and clinical skill acquisition. Further research is required to determine the effectiveness of use of HFHS as an educational strategy to improve knowledge acquisition and communication skills. Copyright 2015, SLACK Incorporated.

  16. Relaxation training for anxiety: a ten-years systematic review with meta-analysis

    Science.gov (United States)

    Manzoni, Gian Mauro; Pagnini, Francesco; Castelnuovo, Gianluca; Molinari, Enrico

    2008-01-01

    Background Relaxation training is a common treatment for anxiety problems. Lacking is a recent quantitative meta-analysis that enhances understanding of the variability and clinical significance of anxiety reduction outcomes after relaxation treatment. Methods All studies (1997–2007), both RCT, observational and without control group, evaluating the efficacy of relaxation training (Jacobson's progressive relaxation, autogenic training, applied relaxation and meditation) for anxiety problems and disorders were identified by comprehensive electronic searches with Pubmed, Psychinfo and Cochrane Registers, by checking references of relevant studies and of other reviews. Our primary outcome was anxiety measured with psychometric questionnaires. Meta-analysis was undertaken synthesizing the data from all trials, distinguishing within and between effect sizes. Results 27 studies qualified for the inclusion in the meta-analysis. As hypothesized, relaxation training showed a medium-large effect size in the treatment of anxiety. Cohen's d was .57 (95% CI: .52 to .68) in the within analysis and .51 (95% CI: .46 to .634) in the between group analysis. Efficacy was higher for meditation, among volunteers and for longer treatments. Implications and limitations are discussed. Conclusion The results show consistent and significant efficacy of relaxation training in reducing anxiety. This meta-analysis extends the existing literature through facilitation of a better understanding of the variability and clinical significance of anxiety improvement subsequent to relaxation training. PMID:18518981

  17. Relaxation training for anxiety: a ten-years systematic review with meta-analysis

    Directory of Open Access Journals (Sweden)

    Castelnuovo Gianluca

    2008-06-01

    Full Text Available Abstract Background Relaxation training is a common treatment for anxiety problems. Lacking is a recent quantitative meta-analysis that enhances understanding of the variability and clinical significance of anxiety reduction outcomes after relaxation treatment. Methods All studies (1997–2007, both RCT, observational and without control group, evaluating the efficacy of relaxation training (Jacobson's progressive relaxation, autogenic training, applied relaxation and meditation for anxiety problems and disorders were identified by comprehensive electronic searches with Pubmed, Psychinfo and Cochrane Registers, by checking references of relevant studies and of other reviews. Our primary outcome was anxiety measured with psychometric questionnaires. Meta-analysis was undertaken synthesizing the data from all trials, distinguishing within and between effect sizes. Results 27 studies qualified for the inclusion in the meta-analysis. As hypothesized, relaxation training showed a medium-large effect size in the treatment of anxiety. Cohen's d was .57 (95% CI: .52 to .68 in the within analysis and .51 (95% CI: .46 to .634 in the between group analysis. Efficacy was higher for meditation, among volunteers and for longer treatments. Implications and limitations are discussed. Conclusion The results show consistent and significant efficacy of relaxation training in reducing anxiety. This meta-analysis extends the existing literature through facilitation of a better understanding of the variability and clinical significance of anxiety improvement subsequent to relaxation training.

  18. Music therapy research in the NICU: an updated meta-analysis.

    Science.gov (United States)

    Standley, Jayne

    2012-01-01

    To provide an overview of developmental and medical benefits of music therapy for preterm infants. Meta-analysis. Empirical music studies with preterm infants in the neonatal intensive care unit (NICU). Evidence-based NICU music therapy (NICU -MT ) was highly beneficial with an overall large significant effect size (Cohen's d = 0.82). Effects because of music were consistently in a positive direction. Results of the current analysis replicated findings of a prior meta-analysis and included extended use of music.(1) Benefits were greatest for live music therapy (MT ) and for use early in the infant's NICU stay (birth weight music listening for pacification, music reinforcement of sucking, and music pacification as the basis for multilayered, multimodal stimulation.

  19. A Meta-Analysis of Attachment to Parents and Delinquency

    Science.gov (United States)

    Hoeve, Machteld; Stams, Geert Jan J. M.; van der Put, Claudia E.; Dubas, Judith Semon; van der Laan, Peter H.; Gerris, Jan R. M.

    2012-01-01

    To investigate the link between attachment to parents and delinquency, and the potential moderating effects of age and sex, 74 published and unpublished manuscripts (N = 55,537 participants) were subjected to a multilevel meta-analysis. A mean small to moderate effect size was found (r = 0.18). Poor attachment to parents was significantly linked…

  20. Effects of Vegetarian Diets on Blood Lipids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Wang, Fenglei; Zheng, Jusheng; Yang, Bo; Jiang, Jiajing; Fu, Yuanqing; Li, Duo

    2015-10-27

    Vegetarian diets exclude all animal flesh and are being widely adopted by an increasing number of people; however, effects on blood lipid concentrations remain unclear. This meta-analysis aimed to quantitatively assess the overall effects of vegetarian diets on blood lipids. We searched PubMed, Scopus, Embase, ISI Web of Knowledge, and the Cochrane Library through March 2015. Studies were included if they described the effectiveness of vegetarian diets on blood lipids (total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride). Weighted mean effect sizes were calculated for net changes by using a random-effects model. We performed subgroup and univariate meta-regression analyses to explore sources of heterogeneity. Eleven trials were included in the meta-analysis. Vegetarian diets significantly lowered blood concentrations of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol, and the pooled estimated changes were -0.36 mmol/L (95% CI -0.55 to -0.17; PVegetarian diets did not significantly affect blood triglyceride concentrations, with a pooled estimated mean difference of 0.04 mmol/L (95% CI -0.05 to 0.13; P=0.40). This systematic review and meta-analysis provides evidence that vegetarian diets effectively lower blood concentrations of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol. Such diets could be a useful nonpharmaceutical means of managing dyslipidemia, especially hypercholesterolemia. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  1. Meta-analysis: Problems with Russian Publications.

    Science.gov (United States)

    Verbitskaya, E V

    2015-01-01

    Meta-analysis is a powerful tool to identify Evidence Based medical technologies (interventions) for use in every day practice. Meta-analysis uses statistical approaches to combine results from multiple studies in an effort to increase power (over individual studies), improve estimates of the size of the effect and/or to resolve uncertainty when reports disagree. Meta-analysis is a quantitative, formal study design used to systematically assess previous research studies to derive conclusions from this research. Meta-analysis may provide more precise estimate of the effect of treatment or risk factor for a disease, or other outcomes, than any individual study contributing to the pooled analysis.We have quite a substantial number of Russian medical publications, but not so many Meta-Analyses published in Russian. Russian publications are cited in English language papers not so often. A total of 90% of clinical studies included in published Meta-Analyses incorporate only English language papers. International studies or papers with Russian co-authors are published in English language. The main question is: what is the problem with inclusion of Russian medical publications in Meta-Analysis? The main reasons for this are the following: 1) It is difficult to find Russian papers, difficult to work with them and to work with Russian journals:a. There are single Russian Biomedical Journals, which are translated into English and are included in databases (PubMed, Scopus and other), despite the fact that all of them have English language abstracts.b. The majority the meta-analyses authors use in their work different citation management software such as the Mendeley, Reference Manager, ProCite, EndNote, and others. These citation management systems allow scientists to organize their own literature databases with internet searches and have adds-on for the Office programs what makes process of literature citation very convenient. The Internet sites of the majority of

  2. Are computers effective lie detectors? A meta-analysis of linguistic cues to deception.

    Science.gov (United States)

    Hauch, Valerie; Blandón-Gitlin, Iris; Masip, Jaume; Sporer, Siegfried L

    2015-11-01

    This meta-analysis investigates linguistic cues to deception and whether these cues can be detected with computer programs. We integrated operational definitions for 79 cues from 44 studies where software had been used to identify linguistic deception cues. These cues were allocated to six research questions. As expected, the meta-analyses demonstrated that, relative to truth-tellers, liars experienced greater cognitive load, expressed more negative emotions, distanced themselves more from events, expressed fewer sensory-perceptual words, and referred less often to cognitive processes. However, liars were not more uncertain than truth-tellers. These effects were moderated by event type, involvement, emotional valence, intensity of interaction, motivation, and other moderators. Although the overall effect size was small, theory-driven predictions for certain cues received support. These findings not only further our knowledge about the usefulness of linguistic cues to detect deception with computers in applied settings but also elucidate the relationship between language and deception. © 2014 by the Society for Personality and Social Psychology, Inc.

  3. Detecting small-study effects and funnel plot asymmetry in meta-analysis of survival data: A comparison of new and existing tests.

    Science.gov (United States)

    Debray, Thomas P A; Moons, Karel G M; Riley, Richard D

    2018-03-01

    Small-study effects are a common threat in systematic reviews and may indicate publication bias. Their existence is often verified by visual inspection of the funnel plot. Formal tests to assess the presence of funnel plot asymmetry typically estimate the association between the reported effect size and their standard error, the total sample size, or the inverse of the total sample size. In this paper, we demonstrate that the application of these tests may be less appropriate in meta-analysis of survival data, where censoring influences statistical significance of the hazard ratio. We subsequently propose 2 new tests that are based on the total number of observed events and adopt a multiplicative variance component. We compare the performance of the various funnel plot asymmetry tests in an extensive simulation study where we varied the true hazard ratio (0.5 to 1), the number of published trials (N=10 to 100), the degree of censoring within trials (0% to 90%), and the mechanism leading to participant dropout (noninformative versus informative). Results demonstrate that previous well-known tests for detecting funnel plot asymmetry suffer from low power or excessive type-I error rates in meta-analysis of survival data, particularly when trials are affected by participant dropout. Because our novel test (adopting estimates of the asymptotic precision as study weights) yields reasonable power and maintains appropriate type-I error rates, we recommend its use to evaluate funnel plot asymmetry in meta-analysis of survival data. The use of funnel plot asymmetry tests should, however, be avoided when there are few trials available for any meta-analysis. © 2017 The Authors. Research Synthesis Methods Published by John Wiley & Sons, Ltd.

  4. Virtual reality exposure therapy for anxiety disorders: A meta-analysis

    NARCIS (Netherlands)

    Powers, M.B.; Emmelkamp, P.M.G.

    2008-01-01

    There is now a substantial literature investigating virtual reality exposure therapy (VRET) as a viable treatment option for anxiety disorders. In this meta-analysis we provide effect size estimates for virtual reality treatment in comparison to in vivo exposure and control conditions (waitlist,

  5. Efficacy of computer technology-based HIV prevention interventions: a meta-analysis.

    Science.gov (United States)

    Noar, Seth M; Black, Hulda G; Pierce, Larson B

    2009-01-02

    To conduct a meta-analysis of computer technology-based HIV prevention behavioral interventions aimed at increasing condom use among a variety of at-risk populations. Systematic review and meta-analysis of existing published and unpublished studies testing computer-based interventions. Meta-analytic techniques were used to compute and aggregate effect sizes for 12 randomized controlled trials that met inclusion criteria. Variables that had the potential to moderate intervention efficacy were also tested. The overall mean weighted effect size for condom use was d = 0.259 (95% confidence interval = 0.201, 0.317; Z = 8.74, P partners, and incident sexually transmitted diseases. In addition, interventions were significantly more efficacious when they were directed at men or women (versus mixed sex groups), utilized individualized tailoring, used a Stages of Change model, and had more intervention sessions. Computer technology-based HIV prevention interventions have similar efficacy to more traditional human-delivered interventions. Given their low cost to deliver, ability to customize intervention content, and flexible dissemination channels, they hold much promise for the future of HIV prevention.

  6. Effectiveness of internet-based affect induction procedures: A systematic review and meta-analysis.

    Science.gov (United States)

    Ferrer, Rebecca A; Grenen, Emily G; Taber, Jennifer M

    2015-12-01

    Procedures used to induce affect in a laboratory are effective and well-validated. Given recent methodological and technological advances in Internet research, it is important to determine whether affect can be effectively induced using Internet methodology. We conducted a meta-analysis and systematic review of prior research that has used Internet-based affect induction procedures, and examined potential moderators of the effectiveness of affect induction procedures. Twenty-six studies were included in final analyses, with 89 independent effect sizes. Affect induction procedures effectively induced general positive affect, general negative affect, fear, disgust, anger, sadness, and guilt, but did not significantly induce happiness. Contamination of other nontarget affect did not appear to be a major concern. Video inductions resulted in greater effect sizes. Overall, results indicate that affect can be effectively induced in Internet studies, suggesting an important venue for the acceleration of affective science. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  7. Effects of different lower-limb sensory stimulation strategies on postural regulation?A systematic review and meta-analysis

    OpenAIRE

    Woo, Mei Teng; Davids, Keith; Liukkonen, Jarmo; Orth, Dominic; Chow, Jia Yi; Jaakkola, Timo

    2017-01-01

    Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high- pooled effect sizes (Unbiased (Hedges’ g) standardized mean differences ...

  8. Effect of Exercise Intervention on Flow-Mediated Dilation in Overweight and Obese Adults: Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Younsun Son

    2017-01-01

    Full Text Available The objective of this meta-analysis is to summarize the effect of exercise intervention on flow-mediated dilatation (FMD in overweight and obese adults. We searched four electronic databases (PubMed/Medline, Scopus, and CINAHL through June 2016 for relevant studies pertaining to the effectiveness of exercise intervention on FMD. Seventeen of the 91 studies identified met the inclusion criteria. Comprehensive Meta-Analysis software (version 3 was used to compute the standardized mean difference effect size (ES and 95% CI using a random effects model. We calculated 34 ESs. We found that exercise intervention had medium and positive effects on FMD, with an overall ES of 0.522 (95% CI = 0.257, 0.786. Heterogeneity of ESs was observed (Qb=239, p≤0.001, I2 = 86.19, and the effect was moderated by comorbidity (Qb = 6.39, df = 1, p=0.011. A large ES for the combination exercise, low intensity exercise, and comorbidity subgroups (ES = 0.82~1.24 was found. We conclude that while exercise intervention significantly improves FMD in overweight and obese adults, the effect may depend on the different characteristics of exercise intervention and on participants’ demographics.

  9. The Psychological Effects of Meditation: A Meta-Analysis

    Science.gov (United States)

    Sedlmeier, Peter; Eberth, Juliane; Schwarz, Marcus; Zimmermann, Doreen; Haarig, Frederik; Jaeger, Sonia; Kunze, Sonja

    2012-01-01

    In this meta-analysis, we give a comprehensive overview of the effects of meditation on psychological variables that can be extracted from empirical studies, concentrating on the effects of meditation on nonclinical groups of adult meditators. Mostly because of methodological problems, almost 3/4 of an initially identified 595 studies had to be…

  10. Direct and Collateral Effects of Peer Tutoring on Social and Behavioral Outcomes: A Meta-Analysis of Single-Case Research

    Science.gov (United States)

    Bowman-Perrott, Lisa; Burke, Mack D.; Zhang, Nan; Zaini, Samar

    2014-01-01

    This meta-analysis examined the direct (primary) and collateral (secondary) effects of peer tutoring on social and behavioral outcomes for 128 participants in prekindergarten through grade 12 across 20 studies using SCR designs. The overall TauU weighted effect size across studies was 0.62 (95% CI [0.58, 0.66]), indicating that a small to moderate…

  11. The Limited Informativeness of Meta-Analyses of Media Effects.

    Science.gov (United States)

    Valkenburg, Patti M

    2015-09-01

    In this issue of Perspectives on Psychological Science, Christopher Ferguson reports on a meta-analysis examining the relationship between children's video game use and several outcome variables, including aggression and attention deficit symptoms (Ferguson, 2015, this issue). In this commentary, I compare Ferguson's nonsignificant effects sizes with earlier meta-analyses on the same topics that yielded larger, significant effect sizes. I argue that Ferguson's choice for partial effects sizes is unjustified on both methodological and theoretical grounds. I then plead for a more constructive debate on the effects of violent video games on children and adolescents. Until now, this debate has been dominated by two camps with diametrically opposed views on the effects of violent media on children. However, even the earliest media effects studies tell us that children can react quite differently to the same media content. Thus, if researchers truly want to understand how media affect children, rather than fight for the presence or absence of effects, they need to adopt a perspective that takes differential susceptibility to media effects more seriously. © The Author(s) 2015.

  12. Treatment effectiveness and fidelity of manual therapy to the knee: A systematic review and meta-analysis.

    Science.gov (United States)

    Salamh, Paul; Cook, Chad; Reiman, Michael P; Sheets, Charles

    2017-09-01

    Manual therapy (MT) is a commonly used treatment for knee osteoarthritis (OA) but to date only one systematic review has explored its effectiveness. The purpos e of the present study was to perform a systematic review and meta-analysis of the literature, to determine the effectiveness and fidelity of studies using MT techniques in individuals with knee OA. Relevant studies were assessed for inclusion. Effectiveness was measured using effect sizes, and methodological bias and treatment fidelity were both explored. Effect sizes were calculated using standardized mean differences (SMD) based on pooled data depending on statistical and clinical heterogeneity, as well as risk of bias. The search captured 2,969 studies; after screening, 12 were included. Four had a low risk of bias and high treatment fidelity. For self-reported function, comparing MT with no treatment resulted in a large effect size (standardized mean difference [SMD] 0.84), as did adding MT to a comparator treatment (SMD 0.78). A significant difference was found for pain when adding MT to a comparator treatment (SMD 0.73). The findings in the present meta-analytical review support the use of MT versus a number of different comparators for improvement in self-reported knee function. Lesser support is present for pain reduction, and no endorsement of functional performance can be made at this time. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Guidance for the utility of linear models in meta-analysis of genetic association studies of binary phenotypes.

    Science.gov (United States)

    Cook, James P; Mahajan, Anubha; Morris, Andrew P

    2017-02-01

    Linear mixed models are increasingly used for the analysis of genome-wide association studies (GWAS) of binary phenotypes because they can efficiently and robustly account for population stratification and relatedness through inclusion of random effects for a genetic relationship matrix. However, the utility of linear (mixed) models in the context of meta-analysis of GWAS of binary phenotypes has not been previously explored. In this investigation, we present simulations to compare the performance of linear and logistic regression models under alternative weighting schemes in a fixed-effects meta-analysis framework, considering designs that incorporate variable case-control imbalance, confounding factors and population stratification. Our results demonstrate that linear models can be used for meta-analysis of GWAS of binary phenotypes, without loss of power, even in the presence of extreme case-control imbalance, provided that one of the following schemes is used: (i) effective sample size weighting of Z-scores or (ii) inverse-variance weighting of allelic effect sizes after conversion onto the log-odds scale. Our conclusions thus provide essential recommendations for the development of robust protocols for meta-analysis of binary phenotypes with linear models.

  14. Effects of incentive programs to stimulate safety belt use : a meta-analysis.

    NARCIS (Netherlands)

    Hagenzieker, M.P. Bijleveld, F.D. & Davidse, R.J.

    1997-01-01

    The effects of campaigns using tangible incentives (rewards) to promote safety belt usage have been evaluated by means of a meta-analytic approach. Two coders extracted a total number of 136 short-term and 114 long-term effect sizes and coded many other variables from 34 journal articles and

  15. Validity of the alcohol purchase task: a meta-analysis.

    Science.gov (United States)

    Kiselica, Andrew M; Webber, Troy A; Bornovalova, Marina A

    2016-05-01

    Behavioral economists assess alcohol consumption as a function of unit price. This method allows construction of demand curves and demand indices, which are thought to provide precise numerical estimates of risk for alcohol problems. One of the more commonly used behavioral economic measures is the Alcohol Purchase Task (APT). Although the APT has shown promise as a measure of risk for alcohol problems, the construct validity and incremental utility of the APT remain unclear. This paper presents a meta-analysis of the APT literature. Sixteen studies were included in the meta-analysis. Studies were gathered via searches of the PsycInfo, PubMed, Web of Science and EconLit research databases. Random-effects meta-analyses with inverse variance weighting were used to calculate summary effect sizes for each demand index-drinking outcome relationship. Moderation of these effects by drinking status (regular versus heavy drinkers) was examined. Additionally, tests of the incremental utility of the APT indices in predicting drinking problems above and beyond measuring alcohol consumption were performed. The APT indices were correlated in the expected directions with drinking outcomes, although many effects were small in size. These effects were typically not moderated by the drinking status of the samples. Additionally, the intensity metric demonstrated incremental utility in predicting alcohol use disorder symptoms beyond measuring drinking. The Alcohol Purchase Task appears to have good construct validity, but limited incremental utility in estimating risk for alcohol problems. © 2015 Society for the Study of Addiction.

  16. Therapy of bovine endometritis with prostaglandin F2α: a meta-analysis.

    Science.gov (United States)

    Haimerl, P; Heuwieser, W; Arlt, S

    2013-05-01

    The objective of the conducted meta-analysis was to assess the efficacy of the treatment of bovine endometritis with PGF(2α) by statistical means. Postpartum uterine infections have a high prevalence and a very negative effect on reproductive performance in dairy cattle. Because of a wide discordance between research results, a meta-analysis of the efficacy of the treatment of bovine endometritis with PGF(2α) was conducted. A comprehensive literature search was performed using online databases to reveal a total of 2,307 references. In addition, 5 articles were retrieved by reviewing citations. After applying specific exclusion criteria and evaluating specific evidence parameters, 5 publications, comprising 6 trials, were eligible for being analyzed by means of meta-analysis. Data for each trial were extracted and analyzed using meta-analysis software Review Manager (version 5.1; The Nordic Cochrane Centre, Copenhagen, Denmark). Estimated effect sizes of PGF(2α) were calculated on calving to first service and calving to conception interval. Prostaglandin F(2α) treatment of cows with chronic endometritis had a negative effect on both reproductive performance parameters. Heterogeneity was substantial for calving to first service and calving to conception interval [I(2) (measure of variation beyond chance)=100 and 87%, respectively]; therefore, random-effects models were used. Sensitivity analysis as well as subgroup analysis showed that the performance of randomization was influential in modifying effect size of PGF(2α) treatment. The funnel plot illustrated a publication bias toward smaller studies that reported a prolonged calving to conception interval after a PGF(2α) treatment. We conclude that the investigation of this subject by means of meta-analysis did not reveal an improvement of reproductive performance of cows with endometritis after treatment with PGF(2α). Furthermore, there is a shortage of comparable high quality studies investigating

  17. Effectiveness of Conceptual Change Texts: A Meta Analysis

    Science.gov (United States)

    Armagan, Fulya Öner; Keskin, Melike Özer; Akin, Beril Salman

    2017-01-01

    The purpose of this study was to determine the overall effectiveness of conceptual change texts (CCTs) on academic achievement and to find out if effectiveness was related to some characteristics of the study. It followed up a Meta-analysis research approach. 42 published and unpublished studies, published between 1995 and 2010, and 42 experiment…

  18. Graphic Organizers and Students with Learning Disabilities: A Meta-Analysis

    Science.gov (United States)

    Dexter, Douglas D.; Hughes, Charles A.

    2011-01-01

    This meta-analysis reviews experimental and quasi-experimental studies in which upper-elementary, intermediate, and secondary students with learning disabilities learned from graphic organizers. Following an exhaustive search for studies meeting specified design criteria, 55 standardized mean effect sizes were extracted from 16 articles involving…

  19. Effects of Nurse-Led Telephone-Based Supportive Interventions for Patients With Cancer: A Meta-Analysis.

    Science.gov (United States)

    Suh, Soon-Rim; Lee, Myung Kyung

    2017-07-01

    To evaluate the effects of nurse-led telephone-based supportive interventions (NTSIs) for patients with cancer.
. Electronic databases, including EMBASE®, MEDLINE, Google Scholar, 
Cochrane Library CENTRAL, ProQuest Medical Library, and CINAHL®, were searched through February 2016.
. 239 studies were identified; 16 were suitable for meta-analysis. Cochrane's risk of bias tool and the Comprehensive Meta-Analysis software were used.
. The authors performed a meta-analysis of 16 trials that met eligibility criteria. Thirteen randomized, controlled trials (RCTs) and three non-RCTs examined a total of 2,912 patients with cancer. Patients who received NTSIs were compared with those who received attentional control or usual care (no intervention).
. Telephone interventions delivered by a nurse in an oncology care setting reduced cancer symptoms with a moderate effect size (ES) (-0.33) and emotional distress with a small ES (-0.12), and improved self-care with a large ES (0.64) and health-related quality of life (HRQOL) with a small ES (0.3). Subgroup analyses indicated that the significant effects of NTSIs on cancer symptoms, emotional distress, and HRQOL were larger for studies that combined an application of a theoretical framework, had a control group given usual care, and used an RTC design.
. The findings suggest that an additional tiered evaluation that has a theoretical underpinning and high-quality methodology is required to confirm the efficacy of NTSI for adoption of specific care models.

  20. Clinical Effectiveness of Occupational Therapy in Mental Health: A Meta-Analysis.

    Science.gov (United States)

    Ikiugu, Moses N; Nissen, Ranelle M; Bellar, Cali; Maassen, Alexya; Van Peursem, Katlin

    The purpose of this study was to estimate the effectiveness of theory-based occupational therapy interventions in improving occupational performance and well-being among people with a mental health diagnosis. The meta-analysis included 11 randomized controlled trials with a total of 520 adult participants with a mental health diagnosis. Outcomes were occupational performance, well-being, or both. We conducted meta-analyses using Comprehensive Meta-Analysis software (Version 3.0) with occupational performance and well-being as the dependent variables. Results indicated a medium effect of intervention on improving occupational performance (mean Hedge's g = 0.50, Z = 4.05, p occupational therapy interventions may be effective in improving occupational performance and well-being among people with a mental health diagnosis and should be an integral part of rehabilitation services in mental health. Copyright © 2017 by the American Occupational Therapy Association, Inc.

  1. Effects of blueberry supplementation on blood pressure: a systematic review and meta-analysis of randomized clinical trials.

    Science.gov (United States)

    Zhu, Y; Sun, J; Lu, W; Wang, X; Wang, X; Han, Z; Qiu, C

    2017-03-01

    Blueberries belong to the genus Vaccinium of the family Ericaceae. A series of epidemiological studies have demonstrated that blueberry polyphenols, particularly blueberry anthocyanins provide significant beneficial effects for humans. However, the findings of clinical studies have been equivocal. Therefore, we sought to assess the potential anti-hypertensive effects of blueberry supplementation through a meta-analysis of available randomized controlled trials (RCTs). A comprehensive literature search of PubMed, The Cochrane Library, AMED (Allied and Complementary Medicine Database), Embase, Web of Science, Wanfang Database, and China National Knowledge Infrastructure were performed to identify potential studies published before June 2015. The standardized mean difference and 95% confidence interval (CI) were used as summary statistics. Net changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP) between the blueberry and placebo groups were calculated by subtracting the values at the end of follow-up from those at baseline. Meta-regression was used to identify potential moderators of effect size. Six RCT studies with 204 participants were included in our meta-analysis. There was no significant effect of blueberry supplementation on changes in blood pressure (BP) relative to baseline, and there was a mean difference of -0.28 (95% CI: -1.11 to 0.56, I 2 =87%) and -0.5 (95% CI: -1.24 to 0.24, I 2 =84%) mmHg for SBP and DBP, respectively. In summary, the results from this meta-analysis do not favor any clinical efficacy of blueberry supplementation in improving BP. Further well-designed larger RCTs are required to verify the association between blueberry supplementation and BP.

  2. Meta-analysis of the efficacy of psychological and educational interventions to improve academic performance of students with learning disabilities in Iran.

    Science.gov (United States)

    Faramarzi, Salar; Shamsi, Abdolhossein; Samadi, Maryam; Ahmadzade, Maryam

    2015-01-01

    with due attention to the importance of learning disabilities and necessity of presenting interventions for improvement of these disorders in order to prevent future problems, this study used meta-analysis of the research model on the impact of psychological and educational interventions to improve academic performance of students with learning disabilities. with the use of meta-analysis method by integrating the results of various researches, this study specifies the effect of psychological and educational interventions. In this order, 57 studies, which their methodology was accepted, were selected and meta-analysis was performed on them. The research instrument was a meta-analysis checklist. The effect size for the effectiveness of psychological-educational interventions on improving the academic performance of students with mathematics disorder (0.57), impaired writing (0.50) and dyslexia (0.55) were reported. The result of meta-analysis showed that according to Cohen's table, the effect size is above average, and it can be said that educational and psychological interventions improve the academic performance of students with learning disabilities.

  3. The Influence of Social Norms in Consumer Decision Making: A Meta-Analysis

    NARCIS (Netherlands)

    Melnyk, V.; Herpen, van E.; Trijp, van J.C.M.

    2010-01-01

    Although social norms can substantially impact consumer decision making, understanding of how the specification of the norm determines its impact is limited. This meta-analysis (200 independent studies, 659 effect sizes) examines how aspects of social norm specification determine the effect of norms

  4. Social networking online and personality of self-worth : A meta-analysis

    NARCIS (Netherlands)

    Liu, Dong; Baumeister, Roy F.

    2016-01-01

    Social networking sites (SNSs) offer new avenues for interpersonal communication and self-presentation. We report a meta-analysis of 80 studies yielding 143 effect sizes on the effect of self-esteem, narcissism, and loneliness on SNS use. Total SNS use was higher among people low in self-esteem,

  5. Are Parents' Gender Schemas Related to Their Children's Gender-Related Cognitions? A Meta-Analysis.

    Science.gov (United States)

    Tenenbaum, Harriet R.; Leaper, Campbell

    2002-01-01

    Used meta-analysis to examine relationship of parents' gender schemas and their offspring's gender-related cognitions, with samples ranging in age from infancy through early adulthood. Found a small but meaningful effect size (r=.16) indicating a positive correlation between parent gender schema and offspring measures. Effect sizes were influenced…

  6. A meta-analysis of 25 years of mood-creativity research: Hedonic tone, activation, or regulatory focus?

    NARCIS (Netherlands)

    Baas, M.; de Dreu, C.K.W.; Nijstad, B.A.

    2008-01-01

    This meta-analysis synthesized 102 effect sizes reflecting the relation between specific moods and creativity. Effect sizes overall revealed that positive moods produce more creativity than mood-neutral controls (r = .15), but no significant differences between negative moods and mood-neutral

  7. A meta-analysis of 25 years of mood-creativity research : Hedonic tone, activation, or regulatory focus?

    NARCIS (Netherlands)

    Baas, Matthijs; De Dreu, Carsten K. W.; Nijstad, Bernard A.

    This meta-analysis synthesized 102 effect sizes reflecting the relation between specific moods and creativity. Effect sizes overall revealed that positive moods produce more creativity than mood-neutral controls (r =.15), but no significant differences between negative moods and mood-neutral

  8. A meta-analysis of 25 years of mood-creativity research : Hedonic tone, activation, or regulatory focus?

    NARCIS (Netherlands)

    Baas, Matthijs; De Dreu, Carsten K. W.; Nijstad, Bernard A.

    2008-01-01

    This meta-analysis synthesized 102 effect sizes reflecting the relation between specific moods and creativity. Effect sizes overall revealed that positive moods produce more creativity than mood-neutral controls (r =.15), but no significant differences between negative moods and mood-neutral

  9. Impact of Instructional Decisions on the Effectiveness of Cooperative Learning in Chemistry through Meta-Analysis

    Science.gov (United States)

    Apugliese, Andrew; Lewis, Scott E.

    2017-01-01

    Meta-analysis can provide a robust description of the impact of educational reforms and also offer an opportunity to explore the conditions where such reforms are more or less effective. This article describes a meta-analysis on the impact of cooperative learning on students' chemistry understanding. Modifiers in the meta-analysis are purposefully…

  10. Effects of Anthocyanin on Serum Lipids in Dyslipidemia Patients: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Changfeng Liu

    Full Text Available Dyslipidemia was present in most of the patients with coronary heart disease. Epidemiological evidence suggests that anthocyanin has some effects on the serum lipid. However, these results are controversial. This study aimed at collecting current clinical evidence and evaluating the effects of anthocyanin supplementation on total cholesterol (TC, triglyceride (TG, low-density lipoprotein cholesterol (LDL-C, and high-density lipoprotein cholesterol (HDL-C in dialysis patients.The search included PubMed, Web of Science, MEDLINE, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database (up to July 2015 to identify randomized controlled trials (RCTs on the association between anthocyanin and serum lipids. RevMan (version 5.2 was used for Meta-analysis. Meta-regression analysis, sensitivity analysis and Egger's weighted regression tests were performed by using STATA software (version 12.0; StatCorp, College Station, TX, USA.Six studies (seven arms involving 586 subjects were included in this meta-analysis. The results showed that anthocyanin supplementation has significant effects on TC [MD = -24.06, 95% CI(-45.58 to -2.64 mg/dL, I2 = 93%], TG [MD = -26.14, 95%CI(-40.20 to -3.08 mg/dL, I2 = 66%1], LDL-C [MD = -22.10, 95% CI (-34.36 to -9.85 mg/dL, I2 = 61%], and HDL-C(MD = 5.58, 95% CI (1.02 to 10.14 mg/dL;I2 = 90%.Anthocyanin supplementation significantly reduces serum TC, TG, and LDL-C levels in patients with dyslipidemia, and increases HDL-C. Further rigorously designed RCTs with larger sample sizes are needed to confirm the effectiveness of anthocyanin supplementation for dyslipidemia, especially hypo high density lipoprotein cholesterolemia.

  11. The effects of N-methyl D-aspartate and B-adrenergic receptor antagonists on the reconsolidation of reward memory: a meta-analysis.

    Science.gov (United States)

    Das, Ravi K; Freeman, Tom P; Kamboj, Sunjeev K

    2013-03-01

    Pharmacological memory reconsolidation blockade provides a potential mechanism for ameliorating the maladaptive reward memories underlying relapse in addiction. Two of the most promising classes of drug that interfere with reconsolidation and have translational potential for human use are N-methyl-D-aspartate receptor (NMDAR) and B-Adrenergic receptor (B-AR) antagonists. We used meta-analysis and meta-regression to assess the effects of these drugs on the reconsolidation of reward memory in preclinical models of addiction. Pharmacokinetic, mnemonic and methodological factors were assessed for their moderating impact on effect sizes. An analysis of 52 independent effect sizes (NMDAR=30, B-AR=22) found robust effects of both classes of drug on memory reconsolidation, but a far greater overall effect of NMDAR antagonism than B-AR antagonism. Significant moderating effects of drug dose, relapse process and primary reinforcer were found. The findings suggest that reward memory reconsolidation can be robustly targeted by NMDAR antagonists and to a lesser extent, by B-AR antagonists. Implications for future clinical work are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. The Examination of Teacher Burnout in Turkey: A Meta-Analysis

    Science.gov (United States)

    Yorulmaz, Yilmaz Ilker; Altinkurt, Yahya

    2018-01-01

    The purpose of this study is to determine the effect of gender, marital status, subject matter, school type, educational status and seniority variables on teacher burnout. In this regard, a meta-analysis was conducted for the studies on teacher burnout in Turkey. The effect size analyses were performed with 100 studies for gender, 73 for marital…

  13. Effects of prefrontal tDCS on executive function: Methodological considerations revealed by meta-analysis.

    Science.gov (United States)

    Imburgio, Michael J; Orr, Joseph M

    2018-05-01

    A meta-analysis of studies using single-session transcranial direct current stimulation (tDCS) to target the dorsolateral prefrontal cortex (DLPFC) was undertaken to examine the effect of stimulation on executive function (EF) in healthy samples. 27 studies were included in analyses, yielding 71 effect sizes. The most relevant measure for each task was determined a priori and used to calculate Hedge's g. Methodological characteristics of each study were examined individually as potential moderators of effect size. Stimulation effects on three domains of EF (inhibition of prepotent responses, mental set shifting, and information updating and monitoring) were analyzed separately. In line with previous work, the current study found no significant effect of anodal unilateral tDCS, cathodal unilateral tDCS, or bilateral tDCS on EF. Further moderator and subgroup analyses were only carried out for anodal unilateral montages due to the small number of studies using other montages. Subgroup analyses revealed a significant effect of anodal unilateral tDCS on updating tasks, but not on inhibition or set-shifting tasks. Cathode location significantly moderated the effect of anodal unilateral tDCS. Extracranial cathodes yielded a significant effect on EF while cranial cathodes yielded no effect. Anode size also significantly moderated effect of anodal unilateral tDCS, with smaller anodes being more effective than larger anodes. In summary, anodal DLPFC stimulation is more effective at improving updating ability than inhibition and set-shifting ability, but anodal stimulation can significantly improve general executive function when extracranial cathodes or small anodes are used. Future meta-analyses may examine how stimulation's effects on specific behavioral tasks, rather than broader domains, might be affected by methodological moderators. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. The Impact of Multiple Endpoint Dependency on "Q" and "I"[superscript 2] in Meta-Analysis

    Science.gov (United States)

    Thompson, Christopher Glen; Becker, Betsy Jane

    2014-01-01

    A common assumption in meta-analysis is that effect sizes are independent. When correlated effect sizes are analyzed using traditional univariate techniques, this assumption is violated. This research assesses the impact of dependence arising from treatment-control studies with multiple endpoints on homogeneity measures "Q" and…

  15. Planning future studies based on the conditional power of a meta-analysis

    Science.gov (United States)

    Roloff, Verena; Higgins, Julian PT; Sutton, Alex J

    2013-01-01

    Systematic reviews often provide recommendations for further research. When meta-analyses are inconclusive, such recommendations typically argue for further studies to be conducted. However, the nature and amount of future research should depend on the nature and amount of the existing research. We propose a method based on conditional power to make these recommendations more specific. Assuming a random-effects meta-analysis model, we evaluate the influence of the number of additional studies, of their information sizes and of the heterogeneity anticipated among them on the ability of an updated meta-analysis to detect a prespecified effect size. The conditional powers of possible design alternatives can be summarized in a simple graph which can also be the basis for decision making. We use three examples from the Cochrane Database of Systematic Reviews to demonstrate our strategy. We demonstrate that if heterogeneity is anticipated, it might not be possible for a single study to reach the desirable power no matter how large it is. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22786670

  16. The Effects of Mobile-Computer-Supported Collaborative Learning: Meta-Analysis and Critical Synthesis.

    Science.gov (United States)

    Sung, Yao-Ting; Yang, Je-Ming; Lee, Han-Yueh

    2017-08-01

    One of the trends in collaborative learning is using mobile devices for supporting the process and products of collaboration, which has been forming the field of mobile-computer-supported collaborative learning (mCSCL). Although mobile devices have become valuable collaborative learning tools, evaluative evidence for their substantial contributions to collaborative learning is still scarce. The present meta-analysis, which included 48 peer-reviewed journal articles and doctoral dissertations written over a 16-year period (2000-2015) involving 5,294 participants, revealed that mCSCL has produced meaningful improvements for collaborative learning, with an overall mean effect size of 0.516. Moderator variables, such as domain subject, group size, teaching method, intervention duration, and reward method were related to different effect sizes. The results provided implications for future research and practice, such as suggestions on how to appropriately use the functionalities of mobile devices, how to best leverage mCSCL through effective group learning mechanisms, and what outcome variables should be included in future studies to fully elucidate the process and products of mCSCL.

  17. Theory of planned behavior interventions for reducing heterosexual risk behaviors: A meta-analysis.

    Science.gov (United States)

    Tyson, Mandy; Covey, Judith; Rosenthal, Harriet E S

    2014-12-01

    The meta-analysis reported here examined interventions informed by the theory of planned behavior (TPB) or theory of reasoned action (TRA) aimed at reducing heterosexual risk behaviors (prevention of STDs and unwanted pregnancy). Studies were eligible for inclusion if they were either randomized control trials or quasi-experimental studies that compared the TPB-based intervention against a control group. Search strategy consisted of articles identified in previous reviews, keyword search through search engines, examination of key journals, and contacting key experts. Forty-seven intervention studies were included in the meta-analysis. Random effects models revealed that pooled effect sizes for TPB-based interventions had small but significant effects on behavior and other secondary outcomes (i.e., knowledge, attitudes, normative beliefs, perceived behavioral control, and intentions). Significant heterogeneity found between effect sizes was explored using metaregression. Larger effects were found for interventions that provided opportunities for social comparison. The TPB provides a valuable framework for designing interventions to change heterosexual risk behaviors. However, effect sizes varied quite substantially between studies, and further research is needed to explore the reasons why.

  18. Psychological approaches in the treatment of specific phobias: A meta-analysis

    NARCIS (Netherlands)

    Wolitzky-Taylor, K.B.; Horowitz, J.D.; Powers, M.B.; Telch, M.J.

    2008-01-01

    Data from 33 randomized treatment studies were subjected to a meta-analysis to address questions surrounding the efficacy of psychological approaches in the treatment of specific phobia. As expected, exposure-based treatment produced large effects sizes relative to no treatment. They also

  19. Effect of dipeptidyl peptidase-4 inhibitors on circulating tumor necrosis factor-α concentrations: A systematic review and meta-analysis of controlled trials.

    Science.gov (United States)

    Atkin, Stephen L; Katsiki, Niki; Banach, Maciej; Mikhailidis, Dimitri P; Pirro, Matteo; Sahebkar, Amirhossein

    2017-09-01

    Dipeptidyl peptidase-4 (DPP-4) inhibitors improve glycemic control in patients with type 2 diabetes mellitus. There are also reports of an effect of these drugs in reducing inflammation through inhibition of tumor necrosis factor-α (TNF-α) that is an important mediator for several inflammatory processes. The present systematic review and meta-analysis were performed to evaluate the effect of DPP-4 inhibitors on circulating TNF-α levels in T2DM patients. A systematic review and a meta-analysis were undertaken on all controlled trials of DPP-4 inhibitors that included measurement of TNF-α. The search included PubMed-Medline, Scopus, ISI Web of Knowledge and Google Scholar databases. Quantitative data synthesis was performed using a random-effects model, with standardized mean difference (SMD) and 95% confidence interval (CI) as summary statistics. Meta-regression and leave-one-out sensitivity analysis were performed to assess the modifiers of treatment response. Eight eligible articles (6 with sitagliptin and 2 with vildagliptin) comprising 9 treatment arms were selected for this meta-analysis. Meta-analysis suggested a significant reduction of circulating TNF-α concentrations following treatment with DPP-4 inhibitors (SMD: -1.84, 95% CI: -2.88, -0.80, p=0.001). The effect size was robust in the sensitivity analysis and not mainly driven by a single study. A subgroup analysis did not suggest any significant difference between the TNF-α-lowering activity of sitagliptin (SMD: -1.49, 95% CI: -2.89, -0.10) and vildagliptin (SMD: -2.80, 95% CI: -4.98, -0.61) (p=0.326). This meta-analysis of the 8 available controlled trials showed that DPP-4 inhibition in patients with type 2 diabetes mellitus was associated with significant reductions in plasma TNF-α levels with no apparent difference between sitagliptin and vildagliptin. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Neuropsychological basic deficits in preschoolers at risk for ADHD: a meta-analysis.

    Science.gov (United States)

    Pauli-Pott, Ursula; Becker, Katja

    2011-06-01

    Widely accepted neuropsychological theories on attention deficit hyperactivity disorder (ADHD) assume that the complex symptoms of the disease arise from developmentally preceding neuropsychological basic deficits. These deficits in executive functions and delay aversion are presumed to emerge in the preschool period. The corresponding normative developmental processes include phases of relative stability and rapid change. These non-linear developmental processes might have implications for concurrent and predictive associations between basic deficits and ADHD symptoms. To derive a description of the nature and strength of these associations, a meta-analysis was conducted. It is assumed that weighted mean effect sizes differ between basic deficits and depend on age. The meta-analysis included 25 articles (n=3005 children) in which associations between assessments of basic deficits (i.e. response inhibition, interference control, delay aversion, working memory, flexibility, and vigilance/arousal) in the preschool period and concurrent or subsequent ADHD symptoms or diagnosis of ADHD had been analyzed. For response inhibition and delay aversion, mean effect sizes were of medium to large magnitude while the mean effect size for working memory was small. Meta-regression analyses revealed that effect sizes of delay aversion tasks significantly decreased with increasing age while effect sizes of interference control tasks and Continuous Performance Tests (CPTs) significantly increased. Depending on the normative maturational course of each skill, time windows might exist that allow for a more or less valid assessment of a specific deficit. In future research these time windows might help to describe early developing forms of ADHD and to identify children at risk. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Effects of hippotherapy and therapeutic horseback riding on postural control or balance in children with cerebral palsy: a meta-analysis.

    Science.gov (United States)

    Zadnikar, Monika; Kastrin, Andrej

    2011-08-01

    This research review and meta-analysis presents an overview of the effects of hippotherapy and therapeutic horseback riding (THR) on postural control or balance in children with cerebral palsy (CP). To synthesize previous research findings, a systematic review and meta-analysis were undertaken. Relevant studies were identified by systematic searches of multiple online databases from the inception of the database through to May 2010. Studies were included if they fulfilled the following criteria: (1) quantitative study design, (2) investigation of the effect of hippotherapy or THR on postural control or balance, and (3) the study group comprised children and adults with CP. The selected articles were rated for methodological quality. The treatment effect was coded as a dichotomous outcome (positive effect or no effect) and quantified by odds ratio (OR). The pooled treatment effect was calculated using a random-effects model. Meta-regression of the effect size was performed against study covariates, including study size, publication date, and methodological quality score. From 77 identified studies, 10 met the inclusion criteria. Two were excluded because they did not include a comparison group. Therapy was found to be effective in 76 out of 84 children with CP included in the intervention groups. The comparison groups comprised 89 children: 50 non-disabled and 39 with CP. A positive effect was shown in 21 of the children with CP in the comparison group regardless of the activity undertaken (i.e. physiotherapy, occupational therapy, sitting on a barrel or in an artificial saddle). The pooled effect size estimate was positive (OR 25.41, 95% CI 4.35, 148.53), demonstrating a statistically significant effectiveness of hippotherapy or THR in children with CP (phippotherapy and THR. Although the generalization of our findings may be restricted by the relatively small sample size, the results clearly demonstrate that riding therapy is indicated to improve postural control

  2. A meta-analysis of the published research on the affective, cognitive, and behavioral effects of corporal punishment.

    Science.gov (United States)

    Paolucci, Elizabeth Oddone; Violato, Claudio

    2004-05-01

    The present study is a meta-analysis of the published research on the effects of corporal punishment on affective, cognitive, and behavioral outcomes. The authors included 70 studies published between 1961 and 2000 and involving 47,751 people. Most of the studies were published between 1990 and 2000 (i.e., 53 or 68%) and were conducted in the United States (65 or 83.3%). Each of the dependent variables was coded, and effect sizes (ds) were computed. Average unweighted and weighted ds for each of the outcome variables were .35 and .20 for affective outcomes, .33 and .06 for cognitive outcomes, and .25 and .21 for behavioral outcomes, respectively. The analyses suggested small negative behavioral and emotional effects of corporal punishment and almost no effect of such punishment on cognition. Analyses of several potentially moderating variables, such as gender or socioeconomic status, and the frequency or age of first experience of corporal punishment, the relationship of the person administering the discipline, and the technique of the discipline all had no affect on effect size outcome. There was insufficient data about a number of the moderator variables to conduct meaningful analyses. The results of the present meta-analysis suggest that exposure to corporal punishment does not substantially increase the risk to youth of developing affective, cognitive, or behavioral pathologies.

  3. A systematic review and meta-analysis of the circulatory, erythrocellular and CSF selenium levels in Alzheimer's disease: A metal meta-analysis (AMMA study-I).

    Science.gov (United States)

    Reddy, Varikasuvu Seshadri; Bukke, Suman; Dutt, Naveen; Rana, Puneet; Pandey, Arun Kumar

    2017-07-01

    Available studies in the literature on the selenium levels in Alzheimer's disease (AD) are inconsistent with some studies reporting its decrease in the circulation, while others reported an increase or no change as compared to controls. The objective of this study was to perform a meta-analysis of circulatory (plasma/serum and blood), erythrocyte and cerebrospinal fluid (CSF) selenium levels in AD compared controls. We also performed a meta-analysis of the correlation coefficients (r) to demonstrate the associations between selenium and glutathione peroxidase (GPx) in AD patients. All major databases were searched for eligible studies. We included 12 case-control/observational studies reporting selenium concentrations in AD and controls. Pooled-overall effect size as standardized mean difference (SMD) and pooled r-values were generated using Review Manager 5.3 and MedCalc 15.8 software. Random-effects meta-analysis indicated a decrease in circulatory (SMD=-0.44), erythrocellular (SMD=-0.52) and CSF (SMD=-0.14) selenium levels in AD patients compared to controls. Stratified meta-analysis demonstrated that the selenium levels were decreased in both the subgroups with (SMD=-0.55) and without (SMD=-0.37) age matching between AD and controls. Our results also demonstrated a direct association between decreased selenium levels and GPx in AD. This meta-analysis suggests that circulatory selenium concentration is significantly lower in AD patients compared to controls and this decrease in selenium is directly correlated with an important antioxidant enzyme, the GPx, in AD. Copyright © 2017 Elsevier GmbH. All rights reserved.

  4. Brief psychological therapies for anxiety and depression in primary care: meta-analysis and meta-regression

    Directory of Open Access Journals (Sweden)

    Cape John

    2010-06-01

    Full Text Available Abstract Background Psychological therapies provided in primary care are usually briefer than in secondary care. There has been no recent comprehensive review comparing their effectiveness for common mental health problems. We aimed to compare the effectiveness of different types of brief psychological therapy administered within primary care across and between anxiety, depressive and mixed disorders. Methods Meta-analysis and meta-regression of randomized controlled trials of brief psychological therapies of adult patients with anxiety, depression or mixed common mental health problems treated in primary care compared to primary care treatment as usual. Results Thirty-four studies, involving 3962 patients, were included. Most were of brief cognitive behaviour therapy (CBT; n = 13, counselling (n = 8 or problem solving therapy (PST; n = 12. There was differential effectiveness between studies of CBT, with studies of CBT for anxiety disorders having a pooled effect size [d -1.06, 95% confidence interval (CI -1.31 to -0.80] greater than that of studies of CBT for depression (d -0.33, 95% CI -0.60 to -0.06 or studies of CBT for mixed anxiety and depression (d -0.26, 95% CI -0.44 to -0.08. Counselling for depression and mixed anxiety and depression (d -0.32, 95% CI -0.52 to -0.11 and problem solving therapy (PST for depression and mixed anxiety and depression (d -0.21, 95% CI -0.37 to -0.05 were also effective. Controlling for diagnosis, meta-regression found no difference between CBT, counselling and PST. Conclusions Brief CBT, counselling and PST are all effective treatments in primary care, but effect sizes are low compared to longer length treatments. The exception is brief CBT for anxiety, which has comparable effect sizes.

  5. The effectiveness of evidence-based nursing on development of nursing students' critical thinking: A meta-analysis.

    Science.gov (United States)

    Cui, Chuyun; Li, Yufeng; Geng, Dongrong; Zhang, Hui; Jin, Changde

    2018-06-01

    The aim of this meta-analysis was to assess the effectiveness of evidence-based nursing (EBN) on the development of critical thinking for nursing students. A systematic literature review of original studies on randomized controlled trials was conducted. The relevant randomized controlled trials were retrieved from multiple electronic databases including Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, Web of Science, Cumulative Index to Nursing and Allied Health (CINAHL), Chinese BioMed Database (CBM), China National Knowledge Infrastructure (CNKI), and WanFang Database. In order to make a systematic evaluation, studies were selected according to inclusion and exclusion criteria, and then according to extracted data and assessed quality. The data extraction was completed by two independent reviewers, and the methodological quality assessment was completed by another two reviewers. All of the data was analyzed by the software RevMan5.3. A total of nine studies with 1079 nursing students were chosen in this systematic literature review. The result of this meta-analysis showed that the effectiveness of evidence-based nursing was superior to that of traditional teaching on nursing students' critical thinking. The results of this meta-analysis indicate that evidence-based nursing could help nursing students to promote their development of critical thinking. More researches with higher quality and larger sample size can be analyzed in the further. Copyright © 2018. Published by Elsevier Ltd.

  6. Meta-analysis of vaccine effectiveness of mumps-containing vaccine under different immunization strategies in China.

    Science.gov (United States)

    Wang, Huaqing; Hu, Yongmei; Zhang, Guomin; Zheng, Jingshan; Li, Li; An, Zhijie

    2014-08-20

    To evaluate vaccine effectiveness (VE) of mumps-containing vaccine (MuV) under different immunization strategies. We conducted Medline, Embase, China National Knowledge Internet (CNKI), and Wan Fang Database (WF) searches for Chinese and English language articles describing studies of mumps VE in a Chinese population. Evaluated articles were scored on quality using the Newcastle-Ottawa Scale. Meta-analysis was conducted using random effects models. Sensitivity analysis, subgroup analysis and meta-regression were conducted to explore heterogeneity. A total of 32 studies in 19 papers were included; 14 were case-control studies, and 18 were cohort studies. Half of the studies were of high quality; 41% were of moderate quality. The overall VE for mumps containing vaccine (either one dose or two doses) was 85% (95% CI 76-90%) for cohort studies and 88% (95% CI 82-92%) for case-control studies. Using random effects meta-regression we found significant differences in some study covariates; for instance, VE varied by population (VE=88% in day care versus 69% in pupil, p=0.008) and emergency versus routine immunization (VE=80% for routine immunization versus 95% for emergency immunization, p=0.041). However, these results must be interpreted with caution due to the low number of studies in subgroups, with the permutation test giving non-significant results that indicated that the results may be due to chance. MuV provides good protection from mumps infection. Further studies of mumps VE with larger sample sizes enabling subgroup analyses will be needed to confirm our findings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Workplace interventions to improve work ability: A systematic review and meta-analysis of their effectiveness.

    Science.gov (United States)

    Oakman, Jodi; Neupane, Subas; Proper, Karin I; Kinsman, Natasha; Nygård, Clas-Håkan

    2018-03-01

    Objective Extended working lives due to an ageing population will necessitate the maintenance of work ability across the life course. This systematic review aimed to analyze whether workplace interventions positively impact work ability. Methods We searched Medline, PsycINFO, CINAHL and Embase databases using relevant terms. Work-based interventions were those focused on individuals, the workplace, or multilevel (combination). Work ability - measured using the work ability index (WAI) or the single-item work ability score (WAS) - was the outcome measure. Grading of Recommendations Assessment, Development & Evaluation (GRADE) criteria was used to assess evidence quality, and impact statements were developed to synthesize the results. Meta-analysis was undertaken where appropriate. Results We reviewed 17 randomized control trials (comprising 22 articles). Multilevel interventions (N=5) included changes to work arrangements and liaisons with supervisors, whilst individual-focused interventions (N=12) involved behavior change or exercise programs. We identified only evidence of a moderate quality for either individual or multilevel interventions aiming to improve work ability. The meta-analysis of 13 studies found a small positive significant effect for interventions on work ability [overall pooled mean 0.12, 95% confidence interval (CI) 0.03-0.21] with no heterogeneity for the effect size (Chi 2 =11.28, P=0.51; I 2 =0%). Conclusions The meta-analysis showed a small positive effect, suggesting that workplace interventions might improve work ability. However, the quality of the evidence base was only moderate, precluding any firm conclusion. Further high quality studies are require to establish the role of interventions on work ability.

  8. Assay sensitivity of pain intensity versus pain relief in acute pain clinical trials: ACTTION systematic review and meta-analysis.

    Science.gov (United States)

    Singla, Neil; Hunsinger, Matthew; Chang, Phoebe D; McDermott, Michael P; Chowdhry, Amit K; Desjardins, Paul J; Turk, Dennis C; Dworkin, Robert H

    2015-08-01

    The magnitude of the effect size of an analgesic intervention can be influenced by several factors, including research design. A key design component is the choice of the primary endpoint. The purpose of this meta-analysis was to compare the assay sensitivity of 2 efficacy paradigms: pain intensity (calculated using summed pain intensity difference [SPID]) and pain relief (calculated using total pain relief [TOTPAR]). A systematic review of the literature was performed to identify acute pain studies that calculated both SPIDs and TOTPARs within the same study. Studies were included in this review if they were randomized, double-blind, placebo-controlled investigations involving medications for postsurgical acute pain and if enough data were provided to calculate TOTPAR and SPID standardized effect sizes. Based on a meta-analysis of 45 studies, the mean standardized effect size for TOTPAR (1.13) was .11 higher than that for SPID (1.02; P = .01). Mixed-effects meta-regression analyses found no significant associations between the TOTPAR - SPID difference in standardized effect size and trial design characteristics. Results from this review suggest that for acute pain studies, utilizing TOTPAR to assess pain relief may be more sensitive to treatment effects than utilizing SPID to assess pain intensity. The results of this meta-analysis suggest that TOTPAR may be more sensitive to treatment effects than SPIDs are in analgesic trials examining acute pain. We found that standardized effect sizes were higher for TOTPAR compared to SPIDs. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

  9. Ionizing radiation, antioxidant response and oxidative damage: A meta-analysis.

    Science.gov (United States)

    Einor, D; Bonisoli-Alquati, A; Costantini, D; Mousseau, T A; Møller, A P

    2016-04-01

    One mechanism proposed as a link between exposure to ionizing radiation and detrimental effects on organisms is oxidative damage. To test this hypothesis, we surveyed the scientific literature on the effects of chronic low-dose ionizing radiation (LDIR) on antioxidant responses and oxidative damage. We found 40 publications and 212 effect sizes for antioxidant responses and 288 effect sizes for effects of oxidative damage. We performed a meta-analysis of signed and unsigned effect sizes. We found large unsigned effects for both categories (0.918 for oxidative damage; 0.973 for antioxidant response). Mean signed effect size weighted by sample size was 0.276 for oxidative damage and -0.350 for antioxidant defenses, with significant heterogeneity among effects for both categories, implying that ionizing radiation caused small to intermediate increases in oxidative damage and small to intermediate decreases in antioxidant defenses. Our estimates are robust, as shown by very high fail-safe numbers. Species, biological matrix (tissue, blood, sperm) and age predicted the magnitude of effects for oxidative damage as well as antioxidant response. Meta-regression models showed that effect sizes for oxidative damage varied among species and age classes, while effect sizes for antioxidant responses varied among species and biological matrices. Our results are consistent with the description of mechanisms underlying pathological effects of chronic exposure to LDIR. Our results also highlight the importance of resistance to oxidative stress as one possible mechanism associated with variation in species responses to LDIR-contaminated areas. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Unruptured intracranial aneurysm treatment effects on cognitive function: a meta-analysis.

    Science.gov (United States)

    Bonares, Michael J; Egeto, Peter; de Oliveira Manoel, Airton Leonardo; Vesely, Kristin A; Macdonald, R Loch; Schweizer, Tom A

    2016-03-01

    The treatment of an unruptured intracranial aneurysm (UIA) is not free of morbidity and mortality, and the decision is made by weighing the risks of treatment complications against the risk of aneurysm rupture. This meta-analysis quantitatively analyzed the literature on the effects of UIA treatment on cognition. MEDLINE, Embase, and PsycInfo were systematically searched for studies that reported on the cognitive status of UIA patients before and after aneurysm treatment. The search was restricted to prospective cohort and case-control studies published between January 1, 1998, and January 1, 2013. The analyses focused on the effect of treatment on general cognitive functioning, with an emphasis on 4 specific cognitive domains: executive functions, verbal and visual memory, and visuospatial functions. Eight studies, with a total of 281 patients, were included in the meta-analysis. Treatment did not affect general cognitive functioning (effect size [ES] -0.22 [95% CI -0.78 to 0.34]). Executive functions and verbal memory domains trended toward posttreatment impairment (ES -0.46 [95% CI -0.93 to 0.01] and ES -0.31 [95% CI -1.24 to 0.61]), and performance of visual memory tasks trended toward posttreatment improvement (ES 1.48 [95% CI -0.36 to 3.31]). Lastly, treatment did not significantly affect visuospatial functions (ES -0.08 [95% CI -0.30 to 0.45]). The treatment of an UIA does not seem to affect long-term cognitive function. However, definitive conclusions were not possible due to the paucity of studies addressing this issue.

  11. Clinical Effects and Safety of Zhi Sou San for Cough: A Meta-Analysis of Randomized Trials

    Directory of Open Access Journals (Sweden)

    Ningchang Cheng

    2017-01-01

    Full Text Available Introduction. Zhi Sou San (ZSS, a traditional Chinese prescription, has been widely applied in treating cough. The purpose of this meta-analysis was to evaluate the effectiveness and safety of ZSS for cough. Methods. We searched relevant articles up to 5 March 2017 in seven electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL, MEDLINE, PubMed, Chinese National Knowledge Infrastructure (CNKI, Cqvip Database (VIP, China Biology Medicine disc (CBM, and Wanfang Data. Randomized controlled trials (RCTs were eligible, regardless of blinding. The primary outcome was the total effective rate. Results. Forty-six RCTs with a total of 4007 participants were identified. Compared with western medicine, ZSS significantly improved the total effective rate (OR: 4.45; 95% CI: 3.62–5.47 and the pulmonary function in terms of FEV1 (OR: 0.35; 95% CI: 0.24–0.46 and decreased the adverse reactions (OR: 0.05; 95% CI: 0.02–0.01 and the recurrence rate (OR: 0.30; 95% CI: 0.16–0.57. However, there was no significant improvement in the cough symptom score comparing ZSS with western medicine. Conclusions. This meta-analysis shows that ZSS has significant additional benefits and relative safety in treating cough. However, more rigorously designed investigations and studies, with large sample sizes, are needed because of the methodological flaws and low quality of the included trials in this meta-analysis.

  12. Follow-up treatment effects of contingency management and motivational interviewing on substance use: A meta-analysis.

    Science.gov (United States)

    Sayegh, Caitlin S; Huey, Stanley J; Zara, Erica J; Jhaveri, Kinnari

    2017-06-01

    Motivation is an integral factor in substance use treatment and long-term recovery. However, it is unclear what role intrinsic and extrinsic motivation play across different treatment modalities. A meta-analysis (N = 84) was performed to estimate the pooled effect size of Motivational Interviewing (MI; primarily targeting intrinsic motivation) and contingency management (CM; primarily targeting extrinsic motivation) at different follow-up periods. Collapsed across all substance types, CM had a significant effect at 3-month follow-up, only. In contrast, MI had a significant effect at 6-month follow-up, only. CM had small and medium effects on multiple substances at 3-month follow-up (i.e., tobacco, marijuana, stimulants, polysubstances), but not at 6-month follow-up. MI had 1 significant medium effect at 3-month follow-up (i.e., marijuana), but several significant small effects at 6-month follow-up (i.e., alcohol, tobacco, polysubstances). This meta-analysis suggests that both CM and MI promote reductions in a range of substances, even several months after the intervention concludes. Further, these results provide some evidence that extrinsically focused CM may produce medium follow-up effects in the short run, but intrinsically focused MI may produce small but durable follow-up effects. However, this interpretation is complicated by the differences between the MI and CM studies that preclude statistical tests comparing effect sizes, and few studies assessed motivation itself. Future researchers should investigate how motivational dynamics impact lasting outcomes in substance use treatment. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Depression and oxidative stress: results from a meta-analysis of observational studies.

    Science.gov (United States)

    Palta, Priya; Samuel, Laura J; Miller, Edgar R; Szanton, Sarah L

    2014-01-01

    To perform a systematic review and meta-analysis that quantitatively tests and summarizes the hypothesis that depression results in elevated oxidative stress and lower antioxidant levels. We performed a meta-analysis of studies that reported an association between depression and oxidative stress and/or antioxidant status markers. PubMed and EMBASE databases were searched for articles published from January 1980 through December 2012. A random-effects model, weighted by inverse variance, was performed to pool standard deviation (Cohen's d) effect size estimates across studies for oxidative stress and antioxidant status measures, separately. Twenty-three studies with 4980 participants were included in the meta-analysis. Depression was most commonly measured using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria. A Cohen's d effect size of 0.55 (95% confidence interval = 0.47-0.63) was found for the association between depression and oxidative stress, indicating a roughly 0.55 of 1-standard-deviation increase in oxidative stress among individuals with depression compared with those without depression. The results of the studies displayed significant heterogeneity (I(2) = 80.0%, p < .001). A statistically significant effect was also observed for the association between depression and antioxidant status markers (Cohen's d = -0.24, 95% confidence interval = -0.33 to -0.15). This meta-analysis observed an association between depression and oxidative stress and antioxidant status across many different studies. Differences in measures of depression and markers of oxidative stress and antioxidant status markers could account for the observed heterogeneity. These findings suggest that well-established associations between depression and poor heath outcomes may be mediated by high oxidative stress.

  14. Effects of forage provision to dairy calves on growth performance and rumen fermentation: A meta-analysis and meta-regression.

    Science.gov (United States)

    Imani, M; Mirzaei, M; Baghbanzadeh-Nobari, B; Ghaffari, M H

    2017-02-01

    A meta-analysis of the potential effect of forage provision on growth performance and rumen fermentation of dairy calves was conducted using published data from the literature (1998-2016). Meta-regression was used to evaluate the effects of different forage levels, forage sources, forage offering methods, physical forms of starter, and grain sources on the heterogeneity of the results. We considered 27 studies that reported the effects of forage provision to dairy calves. Estimated effect sizes of forage were calculated on starter feed intake, average daily gain (ADG), feed efficiency (FE), body weight (BW), and rumen fermentation parameters. Intake of starter feed, ADG, BW, ruminal pH, and rumen molar proportion of acetate increased when supplementing forage but FE decreased. Heterogeneity (the amount of variation among studies) was significant for intake of starter feed, ADG, FE, final BW, and rumen fermentation parameters. Improving overall starter feed intake was greater in calves offered alfalfa hay compared with those offered other types of forages. During the milk feeding and overall periods, improving ADG was greater for calves fed a high level of forage (>10% in dry matter) compared with those fed a low level of forage (≤10% in dry matter) diets. The advantages reported in weight gain at a high level of forage could be due to increased gut fill. Improving overall ADG was lower for calves offered forages with textured starter feed compared with ground starter feed. The meta-regression analysis revealed that changes associated with forage provision affect FE differently for various forage sources and forage offering methods during the milk-feeding period. Forage sources also modulated the effect of feeding forage on ruminal pH during the milk-feeding period. In conclusion, forage has the potential to affect starter feed intake and performance of dairy calves, but its effects depend on source, level, and method of forage feeding and physical form of starter

  15. Exercise and Bone Density: Meta-Analysis

    National Research Council Canada - National Science Library

    Kelley, George A; Sharpe-Kelley, Kristi

    2007-01-01

    ...% in both men and women, (2) when conducting meta-analytic research, either the original metric or standardized effect size can be used when analyzing data dealing with the effects of exercise on BMD in adults, (3...

  16. Simulation-based power calculations for planning a two-stage individual participant data meta-analysis.

    Science.gov (United States)

    Ensor, Joie; Burke, Danielle L; Snell, Kym I E; Hemming, Karla; Riley, Richard D

    2018-05-18

    Researchers and funders should consider the statistical power of planned Individual Participant Data (IPD) meta-analysis projects, as they are often time-consuming and costly. We propose simulation-based power calculations utilising a two-stage framework, and illustrate the approach for a planned IPD meta-analysis of randomised trials with continuous outcomes where the aim is to identify treatment-covariate interactions. The simulation approach has four steps: (i) specify an underlying (data generating) statistical model for trials in the IPD meta-analysis; (ii) use readily available information (e.g. from publications) and prior knowledge (e.g. number of studies promising IPD) to specify model parameter values (e.g. control group mean, intervention effect, treatment-covariate interaction); (iii) simulate an IPD meta-analysis dataset of a particular size from the model, and apply a two-stage IPD meta-analysis to obtain the summary estimate of interest (e.g. interaction effect) and its associated p-value; (iv) repeat the previous step (e.g. thousands of times), then estimate the power to detect a genuine effect by the proportion of summary estimates with a significant p-value. In a planned IPD meta-analysis of lifestyle interventions to reduce weight gain in pregnancy, 14 trials (1183 patients) promised their IPD to examine a treatment-BMI interaction (i.e. whether baseline BMI modifies intervention effect on weight gain). Using our simulation-based approach, a two-stage IPD meta-analysis has meta-analysis was appropriate. Pre-specified adjustment for prognostic factors would increase power further. Incorrect dichotomisation of BMI would reduce power by over 20%, similar to immediately throwing away IPD from ten trials. Simulation-based power calculations could inform the planning and funding of IPD projects, and should be used routinely.

  17. Effectiveness of problem-based learning in Chinese pharmacy education: a meta-analysis.

    Science.gov (United States)

    Zhou, Jiyin; Zhou, Shiwen; Huang, Chunji; Xu, Rufu; Zhang, Zuo; Zeng, Shengya; Qian, Guisheng

    2016-01-19

    This review provides a critical overview of problem-based learning (PBL) practices in Chinese pharmacy education. PBL has yet to be widely applied in pharmaceutical education in China. The results of those studies that have been conducted are published in Chinese and thus may not be easily accessible to international researchers. Therefore, this meta-analysis was carried out to review the effectiveness of PBL. Databases were searched for studies in accordance with the inclusion criteria. Two reviewers independently performed the study identification and data extraction. A meta-analysis was conducted using Revman 5.3 software. Sixteen randomized controlled trials were included. The meta-analysis revealed that PBL had a positive association with higher theoretical scores (SMD = 1.17, 95% CI [0.77, 11.57], P methods are superior to conventional teaching methods in improving students' learning interest, independent analysis skills, scope of knowledge, self-study, team spirit, and oral expression. This meta-analysis indicates that PBL pedagogy is superior to traditional lecture-based teaching in Chinese pharmacy education. PBL methods could be an optional, supplementary method of pharmaceutical teaching in China. However, Chinese pharmacy colleges and universities should revise PBL curricula according to their own needs, which would maximize the effectiveness of PBL.

  18. Eliciting mixed emotions: A meta-analysis comparing models, types and measures.

    Directory of Open Access Journals (Sweden)

    Raul eBerrios

    2015-04-01

    Full Text Available The idea that people can experience two oppositely valenced emotions has been controversial ever since early attempts to investigate the construct of mixed emotions. This meta-analysis examined the robustness with which mixed emotions have been elicited experimentally. A systematic literature search identified 63 experimental studies that instigated the experience of mixed emotions. Studies were distinguished according to the structure of the underlying affect model – dimensional or discrete – as well as according to the type of mixed emotions studied (e.g., happy-sad, fearful-happy, positive-negative. The meta-analysis using a random-effects model revealed a moderate to high effect size for the elicitation of mixed emotions (dIG+ = .77, which remained consistent regardless of the structure of the affect model, and across different types of mixed emotions. Several methodological and design moderators were tested. Studies using the minimum index (i.e., the minimum value between a pair of opposite valenced affects resulted in smaller effect sizes, whereas subjective measures of mixed emotions increased the effect sizes. The presence of more women in the samples was also associated with larger effect sizes. The current study indicates that mixed emotions are a robust, measurable and non-artifactual experience. The results are discussed in terms of the implications for an affect system that has greater versatility and flexibility than previously thought.

  19. Eliciting mixed emotions: a meta-analysis comparing models, types, and measures

    Science.gov (United States)

    Berrios, Raul; Totterdell, Peter; Kellett, Stephen

    2015-01-01

    The idea that people can experience two oppositely valenced emotions has been controversial ever since early attempts to investigate the construct of mixed emotions. This meta-analysis examined the robustness with which mixed emotions have been elicited experimentally. A systematic literature search identified 63 experimental studies that instigated the experience of mixed emotions. Studies were distinguished according to the structure of the underlying affect model—dimensional or discrete—as well as according to the type of mixed emotions studied (e.g., happy-sad, fearful-happy, positive-negative). The meta-analysis using a random-effects model revealed a moderate to high effect size for the elicitation of mixed emotions (dIG+ = 0.77), which remained consistent regardless of the structure of the affect model, and across different types of mixed emotions. Several methodological and design moderators were tested. Studies using the minimum index (i.e., the minimum value between a pair of opposite valenced affects) resulted in smaller effect sizes, whereas subjective measures of mixed emotions increased the effect sizes. The presence of more women in the samples was also associated with larger effect sizes. The current study indicates that mixed emotions are a robust, measurable and non-artifactual experience. The results are discussed in terms of the implications for an affect system that has greater versatility and flexibility than previously thought. PMID:25926805

  20. Prevention of Child Sexual Abuse Victimization: A Meta Analysis of School Programs.

    Science.gov (United States)

    Rispens, Jan; Aleman, Andre; Goudena, Paul P.

    1997-01-01

    Meta-analysis of 16 evaluation studies of school programs aimed at the prevention of child sexual abuse victimization found significant and considerable mean postintervention and follow-up effect sizes, indicating that the programs were effective in teaching children sexual abuse concepts and self-protection skills. Program duration and content…

  1. Effect of Continuous Positive Airway Pressure on Adiponectin in Patients with Obstructive Sleep Apnea: A Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Li-Da Chen

    Full Text Available Obstructive sleep apnea (OSA has been suggested to be associated with low levels of adiponectin. Continuous positive airway pressure (CPAP is the gold standard treatment for OSA; however, previous studies assessing the effect of CPAP on adiponectin in patients with OSA yielded conflicting results. The present meta-analysis was performed to determine whether CPAP therapy could increase adiponectin levels.Two reviewers independently searched PubMed, Cochrane library, Embase and Web of Science before February 2015. Information on characteristics of subjects, study design and pre- and post-CPAP treatment of serum adiponectin was extracted for analysis. Standardized mean difference (SMD was used to analyze the summary estimates for CPAP therapy.Eleven studies involving 240 patients were included in this meta-analysis, including ten observational studies and one randomized controlled study. The meta-analysis showed that there was no change of adiponectin levels before and after CPAP treatment in OSA patients (SMD = 0.059, 95% confidence interval (CI = -0.250 to 0.368, z = 0.37, p = 0.710. Subgroup analyses indicated that the results were not affected by age, baseline body mass index, severity of OSA, CPAP therapy duration, sample size and racial differences.This meta-analysis suggested that CPAP therapy has no impact on adiponectin in OSA patients, without significant changes in body weight. Further large-scale, well-designed long-term interventional investigations are needed to clarify this issue.

  2. Effects of conjugated linoleic acid supplementation on serum C-reactive protein: A systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Mazidi, Mohsen; Karimi, Ehsan; Rezaie, Peyman; Ferns, Gordon A

    2017-12-01

    To undertake a systematic review and meta-analysis of prospective studies to determine the effect of conjugated linoleic acids (CLAs) supplementation on serum C-reactive protein (CRP). PubMed-Medline, Web of Science, Cochrane Database, and Google Scholar databases were searched (up until May 2016) to identify prospective studies evaluating the impact of CLAs supplementation on serum CRP. Random-effects models meta-analysis was used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I 2 index. Systematic review registration: CRD42016038945. From a total of 85 entries identified via searches, 14 studies were included in the final selection. The meta-analysis indicated a significant increase in serum CRP concentrations following supplementation with CLAs (weighted mean difference [WMD] 0.63 mg/dL, 95% confidence interval [95% CI] 0.13-1.13, N=21 arms, heterogeneity P=.026; I 2 =52.3%). These findings were robust in sensitivity analyses. Random-effects meta-regression revealed that changes in serum CRP levels were independent of the dosage of CLAs supplementation (slope: -0.02; 95% CI: -0.10, 0.12; P=.889) or duration of follow-up (slope: 0.271; 95% CI: -0.05, 0.59; P=.098). This meta-analysis suggests that CLA supplementation is associated with an increase in plasma CRP concentrations and a reduction in serum adiponectin concentrations, which indicates that CLA supplements have a proinflammatory effect. Randomized control trials with larger sample size and a longer follow-up period may be required for future investigations to provide an unequivocal answer. © 2017 John Wiley & Sons Ltd.

  3. The effect of music therapy on cognitive functions in patients with dementia: a systematic review and meta-analysis.

    Science.gov (United States)

    Fusar-Poli, Laura; Bieleninik, Łucja; Brondino, Natascia; Chen, Xi-Jing; Gold, Christian

    2017-07-10

    The aim of the present study was to meta-analyze the effect of music therapy (MT) on cognitive functions in patients with dementia. A systematic literature search was performed in Medline, PsycINFO, Embase, CINAHL and RILM up to 8 September 2016. We included all randomized controlled trials that compared MT with standard care, or other non-musical types of intervention, evaluating cognitive outcomes in patients with dementia. Outcomes included global cognition, complex attention, executive function, learning and memory, language, and perceptual-motor skills. From 1089 potentially relevant records, 110 studies were assessed for eligibility, and 7 met the inclusion criteria, of which 6 contained appropriate data for meta-analysis (330 participants, mean age range 78.8-86.3). Overall, random-effects meta-analyses suggested no significant effects of MT on all outcomes. Subgroup analysis found evidence of a beneficial effect of active MT on global cognition (SMD = 0.29, 95% CI 0.02 to 0.57, p = 0.04). Despite the limited evidence of the present review, it is important to continue supporting MT as a complementary treatment for older adults with dementia. RCTs with larger sample sizes are needed to better elucidate the impact of MT on cognitive functions.

  4. Meta-analysis for genome-wide association studies using case-control design: application and practice.

    Science.gov (United States)

    Shim, Sungryul; Kim, Jiyoung; Jung, Wonguen; Shin, In-Soo; Bae, Jong-Myon

    2016-01-01

    This review aimed to arrange the process of a systematic review of genome-wide association studies in order to practice and apply a genome-wide meta-analysis (GWMA). The process has a series of five steps: searching and selection, extraction of related information, evaluation of validity, meta-analysis by type of genetic model, and evaluation of heterogeneity. In contrast to intervention meta-analyses, GWMA has to evaluate the Hardy-Weinberg equilibrium (HWE) in the third step and conduct meta-analyses by five potential genetic models, including dominant, recessive, homozygote contrast, heterozygote contrast, and allelic contrast in the fourth step. The 'genhwcci' and 'metan' commands of STATA software evaluate the HWE and calculate a summary effect size, respectively. A meta-regression using the 'metareg' command of STATA should be conducted to evaluate related factors of heterogeneities.

  5. Conventional vs. e-learning in nursing education: A systematic review and meta-analysis.

    Science.gov (United States)

    Voutilainen, Ari; Saaranen, Terhi; Sormunen, Marjorita

    2017-03-01

    By and large, in health professions training, the direction of the effect of e-learning, positive or negative, strongly depends on the learning outcome in question as well as on learning methods which e-learning is compared to. In nursing education, meta-analytically generated knowledge regarding the comparisons between conventional and e-learning is scarce. The aim of this review is to discover the size of the effect of e-learning on learning outcomes in nursing education and to assess the quality of studies in which e-learning has been compared to conventional learning. A systematic search of six electronic databases, PubMed, Ovid MEDLINE®, CINAHL (EBSCOhost), Cochrane Library, PsycINFO, and ERIC, was conducted in order to identify relevant peer-reviewed English language articles published between 2011 and 2015. The quality of the studies included as well as the risk of bias in each study was assessed. A random-effects meta-analysis was performed to generate a pooled mean difference in the learning outcome. Altogether, 10 studies were eligible for the quality assessment and meta-analysis. Nine studies were evaluated as good quality studies, but not without a risk of bias. Performance bias caused a high risk in nearly all the studies. In the meta-analysis, an e-learning method resulted in test scores that were, on average, five points higher than a conventional method on a 0-100 scale. Heterogeneity between the studies was very large. The size and direction of the effect of a learning method on learning outcomes appeared to be strongly situational. We suggest that meta-regressions should be performed instead of basic meta-analyses in order to reveal factors that cause variation in the learning outcomes of nursing education. It might be necessary to perform separate meta-analyses between e-learning interventions aimed at improving nursing knowledge and those aimed at improving nursing skills. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Narcissism and Social Networking Behavior: A Meta-Analysis.

    Science.gov (United States)

    Gnambs, Timo; Appel, Markus

    2018-04-01

    The increasing popularity of social networking sites (SNS) such as Facebook and Twitter has given rise to speculations that the intensity of using these platforms is associated with narcissistic tendencies. However, recent research on this issue has been all but conclusive. We present a three-level, random effects meta-analysis including 289 effect sizes from 57 studies (total N = 25,631) on the association between trait narcissism and social networking behavior. The meta-analysis identified a small to moderate effect of ρ = .17 (τ = .11), 95% CI [.13, .21], for grandiose narcissism that replicated across different social networking platforms, respondent characteristics, and time. Moderator analyses revealed pronounced cultural differences, with stronger associations in power-distant cultures. Moreover, social networking behaviors geared toward self-presentation and the number of SNS friends exhibited stronger effects than usage durations. Overall, the study not only supported but also refined the notion of a relationship between engaging in social networking sites and narcissistic personality traits. © 2017 Wiley Periodicals, Inc.

  7. Protection from sunburn with beta-Carotene--a meta-analysis.

    Science.gov (United States)

    Köpcke, Wolfgang; Krutmann, Jean

    2008-01-01

    Nutritional protection against skin damage from sunlight is increasingly advocated to the general public, but its effectiveness is controversial. In this meta-analysis, we have systematically reviewed the existing literature on human supplementation studies on dietary protection against sunburn by beta-carotene. A review of literature until June 2007 was performed in PubMed, ISI Web of Science and EBM Cochrane library and identified a total of seven studies which evaluated the effectiveness of beta-carotene in protection against sunburn. Data were abstracted from these studies by means of a standardized data collection protocol. The subsequent meta-analysis showed that (1) beta-carotene supplementation protects against sunburn and (2) the study duration had a significant influence on the effected size. Regression plot analysis revealed that protection required a minimum of 10 weeks of supplementation with a mean increase of the protective effect of 0.5 standard deviations with every additional month of supplementation. Thus, dietary supplementation of humans with beta-carotene provides protection against sunburn in a time-dependent manner.

  8. Effect sizes and cut-off points: a meta-analytical review of burnout in latin American countries.

    Science.gov (United States)

    García-Arroyo, Jose; Osca Segovia, Amparo

    2018-05-02

    Burnout is a highly prevalent globalized health issue that causes significant physical and psychological health problems. In Latin America research on this topic has increased in recent years, however there are no studies comparing results across countries, nor normative reference cut-offs. The present meta-analysis examines the intensity of burnout (emotional exhaustion, cynicism and personal accomplishment) in 58 adult nonclinical samples from 8 countries (Argentina, Brazil, Chile, Colombia, Ecuador, Mexico, Peru and Venezuela). We found low intensity of burnout but there are significant differences between countries in emotional exhaustion explained by occupation and language. Social and human service professionals (police officers, social workers, public administration staff) are more exhausted than health professionals (physicians, nurses) or teachers. The samples with Portuguese language score higher in emotional exhaustion than Spanish, supporting the theory of cultural relativism. Demographics (sex, age) and study variables (sample size, instrument), were not found significant to predict burnout. The effect size and confidence intervals found are proposed as a useful baseline for research and medical diagnosis of burnout in Latin American countries.

  9. Transgender Population Size in the United States: a Meta-Regression of Population-Based Probability Samples

    Science.gov (United States)

    Sevelius, Jae M.

    2017-01-01

    Background. Transgender individuals have a gender identity that differs from the sex they were assigned at birth. The population size of transgender individuals in the United States is not well-known, in part because official records, including the US Census, do not include data on gender identity. Population surveys today more often collect transgender-inclusive gender-identity data, and secular trends in culture and the media have created a somewhat more favorable environment for transgender people. Objectives. To estimate the current population size of transgender individuals in the United States and evaluate any trend over time. Search methods. In June and July 2016, we searched PubMed, Cumulative Index to Nursing and Allied Health Literature, and Web of Science for national surveys, as well as “gray” literature, through an Internet search. We limited the search to 2006 through 2016. Selection criteria. We selected population-based surveys that used probability sampling and included self-reported transgender-identity data. Data collection and analysis. We used random-effects meta-analysis to pool eligible surveys and used meta-regression to address our hypothesis that the transgender population size estimate would increase over time. We used subsample and leave-one-out analysis to assess for bias. Main results. Our meta-regression model, based on 12 surveys covering 2007 to 2015, explained 62.5% of model heterogeneity, with a significant effect for each unit increase in survey year (F = 17.122; df = 1,10; b = 0.026%; P = .002). Extrapolating these results to 2016 suggested a current US population size of 390 adults per 100 000, or almost 1 million adults nationally. This estimate may be more indicative for younger adults, who represented more than 50% of the respondents in our analysis. Authors’ conclusions. Future national surveys are likely to observe higher numbers of transgender people. The large variety in questions used to ask

  10. Testing for Questionable Research Practices in a Meta-Analysis: An Example from Experimental Parapsychology.

    Directory of Open Access Journals (Sweden)

    Dick J Bierman

    Full Text Available We describe a method of quantifying the effect of Questionable Research Practices (QRPs on the results of meta-analyses. As an example we simulated a meta-analysis of a controversial telepathy protocol to assess the extent to which these experimental results could be explained by QRPs. Our simulations used the same numbers of studies and trials as the original meta-analysis and the frequencies with which various QRPs were applied in the simulated experiments were based on surveys of experimental psychologists. Results of both the meta-analysis and simulations were characterized by 4 metrics, two describing the trial and mean experiment hit rates (HR of around 31%, where 25% is expected by chance, one the correlation between sample-size and hit-rate, and one the complete P-value distribution of the database. A genetic algorithm optimized the parameters describing the QRPs, and the fitness of the simulated meta-analysis was defined as the sum of the squares of Z-scores for the 4 metrics. Assuming no anomalous effect a good fit to the empirical meta-analysis was found only by using QRPs with unrealistic parameter-values. Restricting the parameter space to ranges observed in studies of QRP occurrence, under the untested assumption that parapsychologists use comparable QRPs, the fit to the published Ganzfeld meta-analysis with no anomalous effect was poor. We allowed for a real anomalous effect, be it unidentified QRPs or a paranormal effect, where the HR ranged from 25% (chance to 31%. With an anomalous HR of 27% the fitness became F = 1.8 (p = 0.47 where F = 0 is a perfect fit. We conclude that the very significant probability cited by the Ganzfeld meta-analysis is likely inflated by QRPs, though results are still significant (p = 0.003 with QRPs. Our study demonstrates that quantitative simulations of QRPs can assess their impact. Since meta-analyses in general might be polluted by QRPs, this method has wide applicability outside the domain of

  11. Testing for Questionable Research Practices in a Meta-Analysis: An Example from Experimental Parapsychology.

    Science.gov (United States)

    Bierman, Dick J; Spottiswoode, James P; Bijl, Aron

    2016-01-01

    We describe a method of quantifying the effect of Questionable Research Practices (QRPs) on the results of meta-analyses. As an example we simulated a meta-analysis of a controversial telepathy protocol to assess the extent to which these experimental results could be explained by QRPs. Our simulations used the same numbers of studies and trials as the original meta-analysis and the frequencies with which various QRPs were applied in the simulated experiments were based on surveys of experimental psychologists. Results of both the meta-analysis and simulations were characterized by 4 metrics, two describing the trial and mean experiment hit rates (HR) of around 31%, where 25% is expected by chance, one the correlation between sample-size and hit-rate, and one the complete P-value distribution of the database. A genetic algorithm optimized the parameters describing the QRPs, and the fitness of the simulated meta-analysis was defined as the sum of the squares of Z-scores for the 4 metrics. Assuming no anomalous effect a good fit to the empirical meta-analysis was found only by using QRPs with unrealistic parameter-values. Restricting the parameter space to ranges observed in studies of QRP occurrence, under the untested assumption that parapsychologists use comparable QRPs, the fit to the published Ganzfeld meta-analysis with no anomalous effect was poor. We allowed for a real anomalous effect, be it unidentified QRPs or a paranormal effect, where the HR ranged from 25% (chance) to 31%. With an anomalous HR of 27% the fitness became F = 1.8 (p = 0.47 where F = 0 is a perfect fit). We conclude that the very significant probability cited by the Ganzfeld meta-analysis is likely inflated by QRPs, though results are still significant (p = 0.003) with QRPs. Our study demonstrates that quantitative simulations of QRPs can assess their impact. Since meta-analyses in general might be polluted by QRPs, this method has wide applicability outside the domain of experimental

  12. Complementary and alternative exercise for fibromyalgia: a meta-analysis.

    Science.gov (United States)

    Mist, Scott David; Firestone, Kari A; Jones, Kim Dupree

    2013-01-01

    Complementary and alternative medicine includes a number of exercise modalities, such as tai chi, qigong, yoga, and a variety of lesser-known movement therapies. A meta-analysis of the current literature was conducted estimating the effect size of the different modalities, study quality and bias, and adverse events. The level of research has been moderately weak to date, but most studies report a medium-to-high effect size in pain reduction. Given the lack of adverse events, there is little risk in recommending these modalities as a critical component in a multimodal treatment plan, which is often required for fibromyalgia management.

  13. Physical activity and body image among men and boys: A meta-analysis.

    Science.gov (United States)

    Bassett-Gunter, Rebecca; McEwan, Desmond; Kamarhie, Aria

    2017-09-01

    Three meta-analytic reviews have concluded that physical activity is positively related to body image. Historically, research regarding physical activity and body image has been disproportionately focused on female samples. For example, the most recent meta-analysis (2009) extracted 56 effect sizes for women and only 12 for men. The current paper provides an update to the literature regarding the relationship between physical activity and body image among men and boys across 84 individual effect sizes. The analysis also provides insight regarding moderator variables including participant age, and physical activity type and intensity. Overall, physical activity was positively related to body image among men and boys with various moderator variables warranting further investigation. Pragmatic implications are discussed as well as the limitations within existing research and need for additional research to further understand moderator and mediator variables. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Apparently conclusive meta-analyses may be inconclusive--Trial sequential analysis adjustment of random error risk due to repetitive testing of accumulating data in apparently conclusive neonatal meta-analyses

    DEFF Research Database (Denmark)

    Brok, Jesper; Thorlund, Kristian; Wetterslev, Jørn

    2008-01-01

    BACKGROUND: Random error may cause misleading evidence in meta-analyses. The required number of participants in a meta-analysis (i.e. information size) should be at least as large as an adequately powered single trial. Trial sequential analysis (TSA) may reduce risk of random errors due to repeti......BACKGROUND: Random error may cause misleading evidence in meta-analyses. The required number of participants in a meta-analysis (i.e. information size) should be at least as large as an adequately powered single trial. Trial sequential analysis (TSA) may reduce risk of random errors due...

  15. The countermovement jump to monitor neuromuscular status: A meta-analysis.

    Science.gov (United States)

    Claudino, João Gustavo; Cronin, John; Mezêncio, Bruno; McMaster, Daniel Travis; McGuigan, Michael; Tricoli, Valmor; Amadio, Alberto Carlos; Serrão, Julio Cerca

    2017-04-01

    The primary objective of this meta-analysis was to compare countermovement jump (CMJ) performance in studies that reported the highest value as opposed to average value for the purposes of monitoring neuromuscular status (i.e., fatigue and supercompensation). The secondary aim was to determine the sensitivity of the dependent variables. Systematic review with meta-analysis. The meta-analysis was conducted on the highest or average of a number of CMJ variables. Multiple literature searches were undertaken in Pubmed, Scopus, and Web of Science to identify articles utilizing CMJ to monitor training status. Effect sizes (ES) with 95% confidence interval (95% CI) were calculated using the mean and standard deviation of the pre- and post-testing data. The coefficient of variation (CV) with 95% CI was also calculated to assess the level of instability of each variable. Heterogeneity was assessed using a random-effects model. 151 articles were included providing a total of 531 ESs for the meta-analyses; 85.4% of articles used highest CMJ height, 13.2% used average and 1.3% used both when reporting changes in CMJ performance. Based on the meta-analysis, average CMJ height was more sensitive than highest CMJ height in detecting CMJ fatigue and supercompensation. Furthermore, other CMJ variables such as peak power, mean power, peak velocity, peak force, mean impulse, and power were sensitive in tracking the supercompensation effects of training. The average CMJ height was more sensitive than highest CMJ height in monitoring neuromuscular status; however, further investigation is needed to determine the sensitivity of other CMJ performance variables. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  16. A meta-analysis and review of holistic face processing.

    Science.gov (United States)

    Richler, Jennifer J; Gauthier, Isabel

    2014-09-01

    The concept of holistic processing is a cornerstone of face recognition research, yet central questions related to holistic processing remain unanswered, and debates have thus far failed to reach a resolution despite accumulating empirical evidence. We argue that a considerable source of confusion in this literature stems from a methodological problem. Specifically, 2 measures of holistic processing based on the composite paradigm (complete design and partial design) are used in the literature, but they often lead to qualitatively different results. First, we present a comprehensive review of the work that directly compares the 2 designs, and which clearly favors the complete design over the partial design. Second, we report a meta-analysis of holistic face processing according to both designs and use this as further evidence for one design over the other. The meta-analysis effect size of holistic processing in the complete design is nearly 3 times that of the partial design. Effect sizes were not correlated between measures, consistent with the suggestion that they do not measure the same thing. Our meta-analysis also examines the correlation between conditions in the complete design of the composite task, and suggests that in an individual differences context, little is gained by including a misaligned baseline. Finally, we offer a comprehensive review of the state of knowledge about holistic processing based on evidence gathered from the measure we favor based on the 1st sections of our review-the complete design-and outline outstanding research questions in that new context. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  17. Identifying effective components of child maltreatment interventions: A meta-analysis

    NARCIS (Netherlands)

    van der Put, C.E.; Assink, M.; Gubbels, J.; Boekhout van Solinge, N.F.

    There is a lack of knowledge about specific components that make interventions effective in preventing or reducing child maltreatment. The aim of the present meta-analysis was to increase this knowledge by summarizing findings on effects of interventions for child maltreatment and by examining

  18. Moderate effects of noninvasive brain stimulation of the frontal cortex for improving negative symptoms in schizophrenia: Meta-analysis of controlled trials.

    Science.gov (United States)

    Aleman, André; Enriquez-Geppert, Stefanie; Knegtering, Henderikus; Dlabac-de Lange, Jozarni J

    2018-06-01

    Negative symptoms in schizophrenia concern a clinically relevant reduction of goal-directed behavior that strongly and negatively impacts daily functioning. Existing treatments are of marginal effect and novel approaches are needed. Noninvasive neurostimulation by means of repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are novel approaches that may hold promise. To provide a quantitative integration of the published evidence regarding effects of rTMS and tDCS over the frontal cortex on negative symptoms, including an analysis of effects of sham stimulation. Meta-analysis was applied, using a random effects model, to calculate mean weighted effect sizes (Cohen's d). Heterogeneity was assessed by using Cochrans Q and I 2 tests. For rTMS treatment, the mean weighted effect size compared to sham stimulation was 0.64 (0.32-0.96; k = 22, total N = 827). Studies with younger participants showed stronger effects as compared to studies with older participants. For tDCS studies a mean weighted effect size of 0.50 (-0.07 to 1.07; k = 5, total N = 134) was found. For all frontal noninvasive neurostimulation studies together (i.e., TMS and tDCS studies combined) active stimulation was superior to sham, the mean weighted effect size was 0.61 (24 studies, 27 comparisons, 95% confidence interval 0.33-0.89; total N = 961). Sham rTMS (baseline - posttreatment comparison) showed a significant improvement of negative symptoms, d = 0.31 (0.09-0.52; k = 16, total N = 333). Whereas previous meta-analyses were underpowered, our meta-analysis had a power of 0.87 to detect a small effect. The available evidence indicates that noninvasive prefrontal neurostimulation can improve negative symptoms. This finding suggests a causal role for the lateral frontal cortex in self-initiated goal-directed behavior. The evidence is stronger for rTMS than for tDCS, although this may be due to the small number of

  19. Neurological Soft Signs in Schizophrenia: A Meta-analysis

    Science.gov (United States)

    Chan, Raymond C. K.; Xu, Ting; Heinrichs, R. Walter; Yu, Yue; Wang, Ya

    2010-01-01

    Background: Neurological soft signs (NSS) are hypothesized as candidate endophenotypes for schizophrenia, but their prevalence and relations with clinical and demographic data are unknown. The authors undertook a quantification (meta-analysis) of the published literature on NSS in patients with schizophrenia and healthy controls. A systematic search was conducted for published articles reporting NSS and related data using standard measures in schizophrenia and healthy comparison groups. Method: A systematic search was conducted for published articles reporting data on the prevalence of NSS in schizophrenia using standard clinical rating scales and healthy comparison groups. Meta-analyses were performed using the Comprehensive Meta-analysis software package. Effect sizes (Cohen d) indexing the difference between schizophrenic patients and the healthy controls were calculated on the basis of reported statistics. Potential moderator variables evaluated included age of patient samples, level of education, sample sex proportions, medication doses, and negative and positive symptoms. Results: A total of 33 articles met inclusion criteria for the meta-analysis. A large and reliable group difference (Cohen d) indicated that, on average, a majority of patients (73%) perform outside the range of healthy subjects on aggregate NSS measures. Cognitive performance and positive and negative symptoms share 2%–10% of their variance with NSS. Conclusions: NSS occur in a majority of the schizophrenia patient population and are largely distinct from symptomatic and cognitive features of the illness. PMID:19377058

  20. Meta-analysis to predict the effects of metabolizable amino acids on dairy cattle performance.

    Science.gov (United States)

    Lean, I J; de Ondarza, M B; Sniffen, C J; Santos, J E P; Griswold, K E

    2018-01-01

    Meta-analytic methods were used to determine statistical relationships between metabolizable AA supplies and milk protein yield, milk protein percentage, and milk yield in lactating dairy cows. Sixty-three research publications (258 treatment means) were identified through a search of published literature using 3 search engines and met the criteria for inclusion in this meta-analysis. The Cornell Net Carbohydrate and Protein System (CNCPS) version 6.5 was used to determine dietary nutrient parameters including metabolizable AA. Two approaches were used to analyze the data. First, mixed models were fitted to determine whether explanatory variables predicted responses. Each mixed model contained a global intercept, a random intercept for each experiment, and data were weighted by the inverse of the SEM squared. The second analysis approach used classical effect size meta-analytical evaluation of responses to treatment weighted by the inverse of the treatment variance and with a random effect of treatment nested within experiment. Regardless of the analytical approach, CNCPS-predicted metabolizable Met (g/d) was associated with milk protein percentage and yield. Milk yield was positively associated with CNCPS-predicted metabolizable His, Leu, Trp, Thr, and nonessential AA (g/d). Milk true protein yield was also associated with CNCPS-predicted metabolizable Leu (g/d). Predicted metabolizable Lysine (g/d) did not increase responses in production outcomes. However, mean metabolizable Lys supply was less than typically recommended and the change with treatment was minimal (157 vs. 162 g; 6.36 vs. 6.38% metabolizable protein). Experiments based solely on Lys or Met interventions were excluded from the study database. It is possible that the inclusion of these experiments may have provided additional insight into the effect of these AA on responses. This meta-analysis supports other research indicating a positive effect of Met and His as co-limiting AA in dairy cows and

  1. A meta-analysis of mismatch negativity in children with attention deficit-hyperactivity disorders.

    Science.gov (United States)

    Cheng, Chia-Hsiung; Chan, Pei-Ying S; Hsieh, Yu-Wei; Chen, Kuan-Fu

    2016-01-26

    Mismatch negativity (MMN) is an optimal neurophysiological signal to assess the integrity of auditory sensory memory and involuntary attention switch. The generation of MMN is independent of overt behavioral requirements, concentration or motivation, and thus serves as a suitable tool to study the perceptual function in children with attention deficit-hyperactivity disorders (ADHD). It remains unclear whether ADHD children showed altered MMN responses. Therefore we performed a meta-analysis of peer-reviewed MMN studies that had targeted both typically developed and ADHD children to examine the pooled effect size. The published articles between 1990 and 2014 were searched in PubMed, Medline, Cochrane, and CINAHL. The mean effect size and a 95% confidence interval (CI) were estimated. Six studies, consisting of 10 individual investigations, were included in the final analysis. A significant effect size of 0.28 was found (p=0.028, 95% CI at 0.03-0.53). These results were also free from publication bias or heterogeneity. In conclusion, our meta-analysis results suggest ADHD children demonstrated a reduced MMN amplitude compared to healthy controls. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: a systematic review and meta-analysis.

    Science.gov (United States)

    Camfield, David A; Stough, Con; Farrimond, Jonathon; Scholey, Andrew B

    2014-08-01

    A systematic review and meta-analysis was conducted on 11 randomized placebo-controlled human studies of acute effects of tea constituents L-theanine and epigallocatechin gallate, administered alone or in combination with caffeine, on cognitive function and mood. The outcome measures of mood were alertness, calmness, and contentedness, derived from the Bond-Lader scales, and state anxiety, from the State-Trait Anxiety Inventory. Cognitive measures assessed were attentional switch, intersensory attention, and rapid visual information processing. Standardized mean differences between placebo and treatment groups are presented for each study and outcome measure. Meta-analysis using a random-effects model was conducted when data were available for three or more studies. Evidence of moderate effect sizes in favor of combined caffeine and L-theanine in the first 2 hours postdose were found for outcome measures Bond-Lader alertness, attentional switching accuracy, and, to a lesser extent, some unisensory and multisensory attentional outcomes. Moderator analysis of caffeine and L-theanine doses revealed trends toward greater change in effect size for caffeine dose than for L-theanine dose, particularly during the first hour postdose. © 2014 International Life Sciences Institute.

  3. In Sync and in Control: A Meta-Analysis of Parent-Child Positive Behavioral Synchrony and Youth Self-Regulation.

    Science.gov (United States)

    Davis, Molly; Bilms, Joanie; Suveg, Cynthia

    2017-12-01

    A growing body of research has highlighted the connection between parent-child positive behavioral synchrony and youth self-regulation; however, this association has yet to be the focus of a meta-analytic review. Therefore, the present meta-analysis aimed to estimate the magnitude of the relation between parent-child positive behavioral synchrony and youth self-regulation and to identify moderator variables that can explain the variability in the degree of this association across the extant literature. A thorough literature search of two major databases, in addition to scanning the reference sections of relevant articles, yielded a total of 10 peer-reviewed articles (24 effect sizes, 658 children) that were eligible for inclusion in the current meta-analysis. Results from the overall mean effect size calculation using a random-effects model indicated that parent-child positive behavioral synchrony was significantly, positively correlated with youth self-regulation and the effect size was medium. Children's ages at the time of synchrony and self-regulation measurements, as well as parent gender, served as significant moderator variables. Findings from the present meta-analysis can help to refine existing theoretical models on the role of the parent-child relationship in youth adjustment. Prevention and intervention efforts may benefit from an increased emphasis on building parent-child positive behavioral synchrony to promote youth self-regulation and thus children's overall well-being. © 2016 Family Process Institute.

  4. Pancreatic size and fat content in diabetes: A systematic review and meta-analysis of imaging studies.

    Directory of Open Access Journals (Sweden)

    Tiago Severo Garcia

    Full Text Available Imaging studies are expected to produce reliable information regarding the size and fat content of the pancreas. However, the available studies have produced inconclusive results. The aim of this study was to perform a systematic review and meta-analysis of imaging studies assessing pancreas size and fat content in patients with type 1 diabetes (T1DM and type 2 diabetes (T2DM.Medline and Embase databases were performed. Studies evaluating pancreatic size (diameter, area or volume and/or fat content by ultrasound, computed tomography, or magnetic resonance imaging in patients with T1DM and/or T2DM as compared to healthy controls were selected. Seventeen studies including 3,403 subjects (284 T1DM patients, 1,139 T2DM patients, and 1,980 control subjects were selected for meta-analyses. Pancreas diameter, area, volume, density, and fat percentage were evaluated.Pancreatic volume was reduced in T1DM and T2DM vs. controls (T1DM vs. controls: -38.72 cm3, 95%CI: -52.25 to -25.19, I2 = 70.2%, p for heterogeneity = 0.018; and T2DM vs. controls: -12.18 cm3, 95%CI: -19.1 to -5.25, I2 = 79.3%, p for heterogeneity = 0.001. Fat content was higher in T2DM vs. controls (+2.73%, 95%CI 0.55 to 4.91, I2 = 82.0%, p for heterogeneity<0.001.Individuals with T1DM and T2DM have reduced pancreas size in comparison with control subjects. Patients with T2DM have increased pancreatic fat content.

  5. Effectiveness of problem-based learning in Chinese dental education: a meta-analysis.

    Science.gov (United States)

    Huang, Beilei; Zheng, Liwei; Li, Chunjie; Li, Li; Yu, Haiyang

    2013-03-01

    This article provides a critical overview of problem-based learning (PBL) practice in dental education in China. Because the application of PBL has not been carried out on a large scale in Chinese dental education, this review was performed to investigate its effectiveness. Databases were searched for studies that met the inclusion criteria, with study identification and data extraction performed by two reviewers independently. Meta-analysis was done with Revman 5.1. Eleven randomized controlled trials were included. The meta-analysis found that PBL had a positive effect on gaining higher theoretical (SMD=0.88, 95% CI [0.46, 1.31], peffect on gaining higher pass rates (RR=1.06, 95% CI [0.97, 1.16], p=0.21). This meta-analysis suggests that the PBL pedagogy is considered superior to the traditional lecture-based teaching in this setting. PBL methods could be an optional supplementary method of dental teaching models in China. However, Chinese dental schools should devise PBL curricula according to their own conditions. The effectiveness of PBL should be optimized maximally with all these limitations.

  6. Effect of B-type natriuretic peptide-guided treatment of chronic heart failure on total mortality and hospitalization: an individual patient meta-analysis

    NARCIS (Netherlands)

    Troughton, Richard W.; Frampton, Christopher M.; Brunner-La Rocca, Hans-Peter; Pfisterer, Matthias; Eurlings, Luc W. M.; Erntell, Hans; Persson, Hans; O'Connor, Christopher M.; Moertl, Deddo; Karlström, Patric; Dahlström, Ulf; Gaggin, Hanna K.; Januzzi, James L.; Berger, Rudolf; Richards, A. Mark; Pinto, Yigal M.; Nicholls, M. Gary

    2014-01-01

    Natriuretic peptide-guided (NP-guided) treatment of heart failure has been tested against standard clinically guided care in multiple studies, but findings have been limited by study size. We sought to perform an individual patient data meta-analysis to evaluate the effect of NP-guided treatment of

  7. Bullying and Suicidal Ideation and Behaviors: A Meta-Analysis

    Science.gov (United States)

    Holt, Melissa K.; Vivolo-Kantor, Alana M.; Polanin, Joshua R.; Holland, Kristin M.; DeGue, Sarah; Matjasko, Jennifer L.; Wolfe, Misty; Reid, Gerald

    2015-01-01

    BACKGROUND AND OBJECTIVES Over the last decade there has been increased attention to the association between bullying involvement (as a victim, perpetrator, or bully-victim) and suicidal ideation/behaviors. We conducted a meta-analysis to estimate the association between bullying involvement and suicidal ideation and behaviors. METHODS We searched multiple online databases and reviewed reference sections of articles derived from searches to identify cross-sectional studies published through July 2013. Using search terms associated with bullying, suicide, and youth, 47 studies (38.3% from the United States, 61.7% in non-US samples) met inclusion criteria. Seven observers independently coded studies and met in pairs to reach consensus. RESULTS Six different meta-analyses were conducted by using 3 predictors (bullying victimization, bullying perpetration, and bully/victim status) and 2 outcomes (suicidal ideation and suicidal behaviors). A total of 280 effect sizes were extracted and multilevel, random effects meta-analyses were performed. Results indicated that each of the predictors were associated with risk for suicidal ideation and behavior (range, 2.12 [95% confidence interval (CI), 1.67–2.69] to 4.02 [95% CI, 2.39–6.76]). Significant heterogeneity remained across each analysis. The bullying perpetration and suicidal behavior effect sizes were moderated by the study’s country of origin; the bully/victim status and suicidal ideation results were moderated by bullying assessment method. CONCLUSIONS Findings demonstrated that involvement in bullying in any capacity is associated with suicidal ideation and behavior. Future research should address mental health implications of bullying involvement to prevent suicidal ideation/behavior. PMID:25560447

  8. Meta-analysis in clinical trials revisited.

    Science.gov (United States)

    DerSimonian, Rebecca; Laird, Nan

    2015-11-01

    In this paper, we revisit a 1986 article we published in this Journal, Meta-Analysis in Clinical Trials, where we introduced a random-effects model to summarize the evidence about treatment efficacy from a number of related clinical trials. Because of its simplicity and ease of implementation, our approach has been widely used (with more than 12,000 citations to date) and the "DerSimonian and Laird method" is now often referred to as the 'standard approach' or a 'popular' method for meta-analysis in medical and clinical research. The method is especially useful for providing an overall effect estimate and for characterizing the heterogeneity of effects across a series of studies. Here, we review the background that led to the original 1986 article, briefly describe the random-effects approach for meta-analysis, explore its use in various settings and trends over time and recommend a refinement to the method using a robust variance estimator for testing overall effect. We conclude with a discussion of repurposing the method for Big Data meta-analysis and Genome Wide Association Studies for studying the importance of genetic variants in complex diseases. Published by Elsevier Inc.

  9. The effect of ginger supplementation on serum C-reactive protein, lipid profile and glycaemia: a systematic review and meta-analysis.

    Science.gov (United States)

    Mazidi, Mohsen; Gao, Hong-Kai; Rezaie, Peyman; Ferns, Gordon A

    2016-01-01

    To undertake a systematic review and meta-analysis of prospective studies to determine the effect of ginger supplementation on serum C-reactive protein (CRP), lipid profile, and glycaemia. PubMed-MEDLINE, Web of Science, Cochrane Database, and Google Scholar databases were searched (up until July 2016) to identify prospective studies evaluating the impact of ginger supplementation on serum CRP. Random-effects model meta-analysis was used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I 2 index. Systematic review registration: CRD42016035973. From a total of 265 entries identified via searches, 9 studies were included in the final selection. The meta-analysis indicated a significant reduction in serum CRP concentrations following ginger supplementation [weighted mean difference (WMD)-0.84 mg/L (95% CI -1.38 to -0.31, I 2 56.3%)]. The WMD for fasting blood glucose and HbA1c was -1.35 mg/dl (95% CI -2.04 to -0.58, I 2 12.1%) and -1.01 (95% CI -1.28 to -0.72, I 2 9.4%), respectively. Moreover, high-density lipoprotein and triglyceride significantly improved after ginger administration [1.16 mg/dl (95% CI 0.52 to 1.08, I 2 12.3%) and -1.63 mg/dl (95% CI -3.10 to -0.17, I 2 8.1%), respectively]. These findings were robust in sensitivity analyses. Random-effects meta-regression revealed that changes in serum CRP levels were independent of the dosage of ginger supplementation (slope -0.20; 95% CI -0.95 to 0.55; p =0.60). This meta-analysis suggests that ginger supplementation significantly reduces serum CRP and improves glycaemia indexes and lipid profile. Randomized control trials with larger sample size and with a longer-term follow-up period should be considered for future investigations.

  10. Meta-analysis for genome-wide association studies using case-control design: application and practice

    Directory of Open Access Journals (Sweden)

    Sungryul Shim

    2016-12-01

    Full Text Available This review aimed to arrange the process of a systematic review of genome-wide association studies in order to practice and apply a genome-wide meta-analysis (GWMA. The process has a series of five steps: searching and selection, extraction of related information, evaluation of validity, meta-analysis by type of genetic model, and evaluation of heterogeneity. In contrast to intervention meta-analyses, GWMA has to evaluate the Hardy–Weinberg equilibrium (HWE in the third step and conduct meta-analyses by five potential genetic models, including dominant, recessive, homozygote contrast, heterozygote contrast, and allelic contrast in the fourth step. The ‘genhwcci’ and ‘metan’ commands of STATA software evaluate the HWE and calculate a summary effect size, respectively. A meta-regression using the ‘metareg’ command of STATA should be conducted to evaluate related factors of heterogeneities.

  11. The Effects of Problem Posing on Student Mathematical Learning: A Meta-Analysis

    Science.gov (United States)

    Rosli, Roslinda; Capraro, Mary Margaret; Capraro, Robert M.

    2014-01-01

    The purpose of the study was to meta-synthesize research findings on the effectiveness of problem posing and to investigate the factors that might affect the incorporation of problem posing in the teaching and learning of mathematics. The eligibility criteria for inclusion of literature in the meta-analysis was: published between 1989 and 2011,…

  12. The effects of psychosis risk variants on brain connectivity: A Meta-analysis

    Directory of Open Access Journals (Sweden)

    Omar eMothersill

    2012-03-01

    Full Text Available In light of observed changes in connectivity in schizophrenia and the highly heritable nature of the disease, neural connectivity may serve as an important intermediate phenotype for schizophrenia. However, how individual variants confer altered connectivity and which measure of brain connectivity is more proximal to the underlying genetic architecture (i.e. functional or structural has not been well delineated. In this review we consider these issues and the relative sensitivity of imaging methodologies to schizophrenia-related changes in connectivity.We searched PubMed for studies considering schizophrenia risk genes AND functional or structural connectivity. Where data was available, summary statistics were used to determine an estimate of effect size (i.e. Cohen’s d. A random-effects meta-analysis was used to consider (1 the largest effect and (2 all significant effects between functional and structural studies. Schizophrenia risk variants involved in neurotransmission, neurodevelopment and myelin function were found to be associated with altered neural connectivity. On average, schizophrenia risk genes had a large effect on functional (mean d=0.76 and structural connectivity (mean d=1.04. The examination of the largest effect size indicated that the outcomes of functional and structural studies were comparable (Q=2.17, p>0.05. Conversely, consideration of effect size estimates for all significant effects suggest that reported effect sizes in structural connectivity studies were more variable than in functional connectivity studies, and that there was a significant lack of homogeneity across the modalities (Q=6.928, p=0.008.Given the more variable profile of effect sizes associated with structural connectivity, these data may suggest that structural imaging methods are more sensitive to a wider range of effects, as opposed to functional studies which may only be able to determine large effects. These conclusions are limited by

  13. Using structural equation modeling for network meta-analysis.

    Science.gov (United States)

    Tu, Yu-Kang; Wu, Yun-Chun

    2017-07-14

    Network meta-analysis overcomes the limitations of traditional pair-wise meta-analysis by incorporating all available evidence into a general statistical framework for simultaneous comparisons of several treatments. Currently, network meta-analyses are undertaken either within the Bayesian hierarchical linear models or frequentist generalized linear mixed models. Structural equation modeling (SEM) is a statistical method originally developed for modeling causal relations among observed and latent variables. As random effect is explicitly modeled as a latent variable in SEM, it is very flexible for analysts to specify complex random effect structure and to make linear and nonlinear constraints on parameters. The aim of this article is to show how to undertake a network meta-analysis within the statistical framework of SEM. We used an example dataset to demonstrate the standard fixed and random effect network meta-analysis models can be easily implemented in SEM. It contains results of 26 studies that directly compared three treatment groups A, B and C for prevention of first bleeding in patients with liver cirrhosis. We also showed that a new approach to network meta-analysis based on the technique of unrestricted weighted least squares (UWLS) method can also be undertaken using SEM. For both the fixed and random effect network meta-analysis, SEM yielded similar coefficients and confidence intervals to those reported in the previous literature. The point estimates of two UWLS models were identical to those in the fixed effect model but the confidence intervals were greater. This is consistent with results from the traditional pairwise meta-analyses. Comparing to UWLS model with common variance adjusted factor, UWLS model with unique variance adjusted factor has greater confidence intervals when the heterogeneity was larger in the pairwise comparison. The UWLS model with unique variance adjusted factor reflects the difference in heterogeneity within each comparison

  14. Robust Variance Estimation with Dependent Effect Sizes: Practical Considerations Including a Software Tutorial in Stata and SPSS

    Science.gov (United States)

    Tanner-Smith, Emily E.; Tipton, Elizabeth

    2014-01-01

    Methodologists have recently proposed robust variance estimation as one way to handle dependent effect sizes in meta-analysis. Software macros for robust variance estimation in meta-analysis are currently available for Stata (StataCorp LP, College Station, TX, USA) and SPSS (IBM, Armonk, NY, USA), yet there is little guidance for authors regarding…

  15. The Effects of Workplace Physical Activity Programs on Musculoskeletal Pain: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Moreira-Silva, Isabel; Teixeira, Pedro M; Santos, Rute; Abreu, Sandra; Moreira, Carla; Mota, Jorge

    2016-05-01

    This article reviews the effectiveness of physical activity (PA) interventions at the workplace to reduce musculoskeletal pain among employees and assesses the effect size of these programs using meta-analysis. Four databases (i.e., PubMed, EBSCO, Web of Science, and Cochrane) were searched for research trials, which included comparison groups of employees that assessed PA programs, musculoskeletal pain, and health-related behaviors, published between January 1990 and March 2013. The meta-analysis estimates of standardized mean differences (Hedges' g) present significant evidence of less general pain (g = -.40 with a 95% confidence interval [CI] = [-0.78, -0.02]) and neck and shoulder pain (g = -.37 with a 95% CI = [-0.63, -0.12]) in intervention groups. The few studies of low back pain and arm, elbow, wrist, hand, or finger pain did not present sufficient statistically significant evidence. Consistent evidence demonstrates that workplace PA interventions significantly reduce general musculoskeletal pain and neck and shoulder pain. More studies are needed to determine the effectiveness of work-related PA interventions for arm, elbow, wrist, hand or finger, and low back pain. © 2016 The Author(s).

  16. Testing moderation in network meta-analysis with individual participant data

    Science.gov (United States)

    Dagne, Getachew A.; Brown, C. Hendricks; Howe, George; Kellam, Sheppard G.; Liu, Lei

    2016-01-01

    Summary Meta-analytic methods for combining data from multiple intervention trials are commonly used to estimate the effectiveness of an intervention. They can also be extended to study comparative effectiveness, testing which of several alternative interventions is expected to have the strongest effect. This often requires network meta-analysis (NMA), which combines trials involving direct comparison of two interventions within the same trial and indirect comparisons across trials. In this paper, we extend existing network methods for main effects to examining moderator effects, allowing for tests of whether intervention effects vary for different populations or when employed in different contexts. In addition, we study how the use of individual participant data (IPD) may increase the sensitivity of NMA for detecting moderator effects, as compared to aggregate data NMA that employs study-level effect sizes in a meta-regression framework. A new network meta-analysis diagram is proposed. We also develop a generalized multilevel model for NMA that takes into account within- and between-trial heterogeneity, and can include participant-level covariates. Within this framework we present definitions of homogeneity and consistency across trials. A simulation study based on this model is used to assess effects on power to detect both main and moderator effects. Results show that power to detect moderation is substantially greater when applied to IPD as compared to study-level effects. We illustrate the use of this method by applying it to data from a classroom-based randomized study that involved two sub-trials, each comparing interventions that were contrasted with separate control groups. PMID:26841367

  17. The Effectiveness of Cognitive Bias Modification Interventions for Substance Addictions: A Meta-Analysis

    DEFF Research Database (Denmark)

    Cristea, Ioana; Kok, Robin; Cuijpers, Pim

    2016-01-01

    Background and Aims Cognitive bias modification (CBM) interventions, presumably targeting automatic processes, are considered particularly promising for addictions. We conducted a meta-analysis examining randomized controlled trials (RCTs) of CBM for substance addiction outcomes. Methods Studies...... were identified through systematic searches in bibliographical databases. We included RCTs of CBM interventions, alone or in combination with other treatments, for any type of addiction. We examined trial risk of bias, publication bias and possible moderators. Effects sizes were computed for post......-test and follow-up, using a random-effects model. We grouped outcome measures and reported results for addiction (all related measures), craving and cognitive bias. Results We identified 25 trials, 18 for alcohol problems, and 7 for smoking. At post-test, there was no significant effect of CBM for addiction, g...

  18. The influence of deliberate practice on musical achievement: A meta-analysis

    Directory of Open Access Journals (Sweden)

    Friedrich ePlatz

    2014-06-01

    Full Text Available Deliberate practice (DP is a task-specific structured training activity that plays a key role in understanding skill acquisition and explaining individual differences in expert performance. Relevant activities that qualify as DP have to be identified in every domain. For example, for training in classical music, solitary practice is a typical training activity during skill acquisition. To date, no meta-analysis on the quantifiable effect size of deliberate practice on attained performance in music has been conducted. Yet the identification of a quantifiable effect size could be relevant for the current discussion on the role of various factors on individual difference in musical achievement. Furthermore, a research synthesis might enable new computational approaches to musical development. Here we present the first meta-analysis on the role of deliberate practice in the domain of musical performance. A final sample size of 13 studies (total N = 788 was carefully extracted to satisfy the following criteria: reported durations of task-specific accumulated practice as predictor variables and objectively assessed musical achievement as the target variable. We identified an aggregated effect size of rc = .61; 95% CI [.54, .67] for the relationship between task-relevant practice (which by definition includes DP and musical achievement. Our results corroborate the central role of long-term (deliberate practice for explaining expert performance in music.

  19. The influence of deliberate practice on musical achievement: a meta-analysis.

    Science.gov (United States)

    Platz, Friedrich; Kopiez, Reinhard; Lehmann, Andreas C; Wolf, Anna

    2014-01-01

    Deliberate practice (DP) is a task-specific structured training activity that plays a key role in understanding skill acquisition and explaining individual differences in expert performance. Relevant activities that qualify as DP have to be identified in every domain. For example, for training in classical music, solitary practice is a typical training activity during skill acquisition. To date, no meta-analysis on the quantifiable effect size of deliberate practice on attained performance in music has been conducted. Yet the identification of a quantifiable effect size could be relevant for the current discussion on the role of various factors on individual difference in musical achievement. Furthermore, a research synthesis might enable new computational approaches to musical development. Here we present the first meta-analysis on the role of deliberate practice in the domain of musical performance. A final sample size of 13 studies (total N = 788) was carefully extracted to satisfy the following criteria: reported durations of task-specific accumulated practice as predictor variables and objectively assessed musical achievement as the target variable. We identified an aggregated effect size of r c = 0.61; 95% CI [0.54, 0.67] for the relationship between task-relevant practice (which by definition includes DP) and musical achievement. Our results corroborate the central role of long-term (deliberate) practice for explaining expert performance in music.

  20. Meta-Analysis of Comparative Studies of Depression in Mothers of Children with and without Developmental Disabilities

    Science.gov (United States)

    Singer, George H. S.

    2006-01-01

    Meta-analysis was used to synthesize findings from comparative studies of depression in mothers of children with and without developmental disabilities. Effect sizes were determined for 18 studies conducted between 1984 and 2003. A weighted effect size of 0.39 indicated an elevated level of depression in mothers of children with developmental…

  1. Upward counterfactual thinking and depression: A meta-analysis.

    Science.gov (United States)

    Broomhall, Anne Gene; Phillips, Wendy J; Hine, Donald W; Loi, Natasha M

    2017-07-01

    This meta-analysis examined the strength of association between upward counterfactual thinking and depressive symptoms. Forty-two effect sizes from a pooled sample of 13,168 respondents produced a weighted average effect size of r=.26, pdesign (cross-sectional versus longitudinal). Significant effect size heterogeneity was observed across sample types, methods of assessing upward counterfactual thinking, and types of depression scale. Significant positive effects were found in studies that employed samples of bereaved individuals, older adults, terminally ill patients, or university students, but not adolescent mothers or mixed samples. Both number-based and Likert-based upward counterfactual thinking assessments produced significant positive effects, with the latter generating a larger effect. All depression scales produced significant positive effects, except for the Psychiatric Epidemiology Research Interview. Research and theoretical implications are discussed in relation to cognitive theories of depression and the functional theory of upward counterfactual thinking, and important gaps in the extant research literature are identified. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. The effectiveness and safety of antifibrinolytics in patients with acute intracranial haemorrhage: statistical analysis plan for an individual patient data meta-analysis

    OpenAIRE

    Ker, Katharine; Prieto-Merino, David; Sprigg, Nikola; Mahmood, Abda; Bath, Philip; Kang Law, Zhe; Flaherty, Katie; Roberts, Ian

    2017-01-01

    Introduction: The Antifibrinolytic Trialists Collaboration aims to increase knowledge about the effectiveness and safety of antifibrinolytic treatment by conducting individual patient data (IPD) meta-analyses of randomised trials. This article presents the statistical analysis plan for an IPD meta-analysis of the effects of antifibrinolytics for acute intracranial haemorrhage. Methods: The protocol for the IPD meta-analysis has been registered with PROSPERO (CRD42016052155). We will conduct a...

  3. Are Leader Stereotypes Masculine? A Meta-Analysis of Three Research Paradigms

    Science.gov (United States)

    Koenig, Anne M.; Eagly, Alice H.; Mitchell, Abigail A.; Ristikari, Tiina

    2011-01-01

    This meta-analysis examined the extent to which stereotypes of leaders are culturally masculine. The primary studies fit into 1 of 3 paradigms: (a) In Schein's (1973) "think manager-think male paradigm", 40 studies with 51 effect sizes compared the similarity of male and leader stereotypes and the similarity of female and leader…

  4. Being tough or being nice? A meta-analysis on the impact of hard- and softline strategies in distributive negotiations

    NARCIS (Netherlands)

    Hüffmeier, J.; Freund, P.A.; Zerres, A.; Backhaus, K.; Hertel, G.

    2014-01-01

    A meta-analysis (34 studies) is reported on the impact of hard- and softline bargaining strategies on economic (135 effect sizes) and socioemotional negotiation outcomes (30 effect sizes) in distributive negotiations. As expected, hardline strategies lead to higher economic outcomes, whereas

  5. A Meta-Analysis on Antecedents and Outcomes of Detachment from Work.

    Science.gov (United States)

    Wendsche, Johannes; Lohmann-Haislah, Andrea

    2016-01-01

    Detachment from work has been proposed as an important non-work experience helping employees to recover from work demands. This meta-analysis (86 publications, k = 91 independent study samples, N = 38,124 employees) examined core antecedents and outcomes of detachment in employee samples. With regard to outcomes, results indicated average positive correlations between detachment and self-reported mental (i.e., less exhaustion, higher life satisfaction, more well-being, better sleep) and physical (i.e., lower physical discomfort) health, state well-being (i.e., less fatigue, higher positive affect, more intensive state of recovery), and task performance (small to medium sized effects). However, average relationships between detachment and physiological stress indicators and work motivation were not significant while associations with contextual performance and creativity were significant, but negative. Concerning work characteristics, as expected, job demands were negatively related and job resources were positively related to detachment (small sized effects). Further, analyses revealed that person characteristics such as negative affectivity/neuroticism (small sized effect) and heavy work investment (medium sized effect) were negatively related to detachment whereas detachment and demographic variables (i.e., age and gender) were not related. Moreover, we found a medium sized average negative relationship between engagement in work-related activities during non-work time and detachment. For most of the examined relationships heterogeneity of effect sizes was moderate to high. We identified study design, samples' gender distribution, and affective valence of work-related thoughts as moderators for some of these aforementioned relationships. The results of this meta-analysis point to detachment as a non-work (recovery) experience that is influenced by work-related and personal characteristics which in turn is relevant for a range of employee outcomes.

  6. Meta-analysis methods for combining multiple expression profiles: comparisons, statistical characterization and an application guideline.

    Science.gov (United States)

    Chang, Lun-Ching; Lin, Hui-Min; Sibille, Etienne; Tseng, George C

    2013-12-21

    As high-throughput genomic technologies become accurate and affordable, an increasing number of data sets have been accumulated in the public domain and genomic information integration and meta-analysis have become routine in biomedical research. In this paper, we focus on microarray meta-analysis, where multiple microarray studies with relevant biological hypotheses are combined in order to improve candidate marker detection. Many methods have been developed and applied in the literature, but their performance and properties have only been minimally investigated. There is currently no clear conclusion or guideline as to the proper choice of a meta-analysis method given an application; the decision essentially requires both statistical and biological considerations. We performed 12 microarray meta-analysis methods for combining multiple simulated expression profiles, and such methods can be categorized for different hypothesis setting purposes: (1) HS(A): DE genes with non-zero effect sizes in all studies, (2) HS(B): DE genes with non-zero effect sizes in one or more studies and (3) HS(r): DE gene with non-zero effect in "majority" of studies. We then performed a comprehensive comparative analysis through six large-scale real applications using four quantitative statistical evaluation criteria: detection capability, biological association, stability and robustness. We elucidated hypothesis settings behind the methods and further apply multi-dimensional scaling (MDS) and an entropy measure to characterize the meta-analysis methods and data structure, respectively. The aggregated results from the simulation study categorized the 12 methods into three hypothesis settings (HS(A), HS(B), and HS(r)). Evaluation in real data and results from MDS and entropy analyses provided an insightful and practical guideline to the choice of the most suitable method in a given application. All source files for simulation and real data are available on the author's publication website.

  7. Anti-tumor effects of metformin in animal models of hepatocellular carcinoma: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Juan Li

    Full Text Available Several studies have reported that metformin can reduce the risk of hepatocellular carcinoma (HCC in diabetes patients. However, the direct anti-HCC effects of metformin have hardly been studied in patients, but have been extensively investigated in animal models of HCC. We therefore performed a systematic review and meta-analysis of animal studies evaluating the effects of metformin on HCC.We collected the relevant studies by searching EMBASE, Medline (OvidSP, Web of Science, Scopus, PubMed Publisher, and Google Scholar. Studies were included according to the following inclusion criteria: HCC, animal study, and metformin intervention. Study quality was assessed using SYRCLE's risk of bias tool. A meta-analysis was performed for the outcome measures: tumor growth (tumor volume, weight and size, tumor number and incidence.The search resulted in 573 references, of which 13 could be included in the review and 12 included in the meta-analysis. The study characteristics of the included studies varied considerably. Two studies used rats, while the others used mice. Only one study used female animals, nine used male, and three studies didn't mention the gender of animals in their experiments. The quality of the included studies was low to moderate based on the assessment of their risk of bias. The meta-analysis showed that metformin significantly inhibited the growth of HCC tumour (SMD -2.20[-2.96,-1.43]; n=16, but no significant effect on the number of tumors (SMD-1.05[-2.13,0.03]; n=5 or the incidence of HCC was observed (RR 0.62[0.33,1.16]; n=6. To investigate the potential sources of significant heterogeneities found in outcome of tumor growth (I2=81%, subgroup analyses of scales of growth measures and of types of animal models used were performed.Metformin appears to have a direct anti-HCC effect in animal models. Although the intrinsic limitations of animal studies, this systematic review could provide an important reference for future

  8. Effects of non-invasive neurostimulation on craving: a meta-analysis

    NARCIS (Netherlands)

    Jansen, Jochem M.; Daams, Joost G.; Koeter, Maarten W. J.; Veltman, Dick J.; van den Brink, Wim; Goudriaan, Anna E.

    2013-01-01

    This meta-analysis was conducted to evaluate the available evidence regarding the effects of non-invasive neurostimulation of the dorsolateral prefrontal cortex (DLPFC), on craving in substance dependence and craving for high palatable food. Non-invasive neurostimulation techniques were restricted

  9. Effects of non-invasive neurostimulation on craving: A meta-analysis

    NARCIS (Netherlands)

    Jansen, J.M.; Daams, J.G.; Koeter, M.W.; Veltman, D.J.; van den Brink, W.; Goudriaan, A.E.

    2013-01-01

    This meta-analysis was conducted to evaluate the available evidence regarding the effects of non-invasive neurostimulation of the dorsolateral prefrontal cortex (DLPFC), on craving in substance dependence and craving for high palatable food. Non-invasive neurostimulation techniques were restricted

  10. The influence of stereotype threat on immigrants: review and meta-analysis

    Science.gov (United States)

    Appel, Markus; Weber, Silvana; Kronberger, Nicole

    2015-01-01

    In many regions around the world students with certain immigrant backgrounds underachieve in educational settings. This paper provides a review and meta-analysis on one potential source of the immigrant achievement gap: stereotype threat, a situational predicament that may prevent students to perform up to their full abilities. A meta-analysis of 19 experiments suggests an overall mean effect size of 0.63 (random effects model) in support of stereotype threat theory. The results are complemented by moderator analyses with regard to circulation (published or unpublished research), cultural context (US versus Europe), age of immigrants, type of stereotype threat manipulation, dependent measures, and means for identification of immigrant status; evidence on the role of ethnic identity strength is reviewed. Theoretical and practical implications of the findings are discussed. PMID:26217256

  11. The Influence of Stereotype Threat on Immigrants: Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Markus eAppel

    2015-07-01

    Full Text Available In many regions around the world students with certain immigrant backgrounds underachieve in educational settings. This paper provides a review and meta-analysis on one potential source of the immigrant achievement gap: stereotype threat, a situational predicament that may prevent students to perform up to their full abilities. A meta-analysis of 19 experiments suggests an overall mean effect size of .63 (random effects model in support of stereotype threat theory. The results are complemented by moderator analyses with regard to circulation (published or unpublished research, cultural context (US vs. Europe, age of immigrants, type of stereotype threat manipulation, dependent measures, and means for identification of immigrant status; evidence on the role of ethnic identity strength is reviewed. Theoretical and practical implications of the findings are discussed.

  12. SLC6A3 polymorphism and response to methylphenidate in children with ADHD: A systematic review and meta-analysis.

    Science.gov (United States)

    Soleimani, Robabeh; Salehi, Zivar; Soltanipour, Soheil; Hasandokht, Tolou; Jalali, Mir Mohammad

    2018-04-01

    Methylphenidate (MPH) is the most commonly used treatment for attention-deficit hyperactivity disorder (ADHD) in children. However, the response to MPH is not similar in all patients. This meta-analysis investigated the potential role of SLC6A3 polymorphisms in response to MPH in children with ADHD. Clinical trials or naturalistic studies were selected from electronic databases. A meta-analysis was conducted using a random-effects model. Cohen's d effect size and 95% confidence intervals (CIs) were determined. Sensitivity analysis and meta-regression were performed. Q-statistic and Egger's tests were conducted to evaluate heterogeneity and publication bias, respectively. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to assess the quality of evidence. Sixteen studies with follow-up periods of 1-28 weeks were eligible. The mean treatment acceptability of MPH was 97.2%. In contrast to clinical trials, the meta-analysis of naturalistic studies indicated that children without 10/10 repeat carriers had better response to MPH (Cohen's d: -0.09 and 0.44, respectively). The 9/9 repeat polymorphism had no effect on the response rate (Cohen's d: -0.43). In the meta-regression, a significant association was observed between baseline severity of ADHD, MPH dosage, and combined type of ADHD in some genetic models. Sensitivity analysis indicated the robustness of our findings. No publication bias was observed in our meta-analysis. The GRADE evaluations revealed very low levels of confidence for each outcome of response to MPH. The results of clinical trials and naturalistic studies regarding the effect size between different polymorphisms of SLC6A3 were contradictory. Therefore, further research is recommended. © 2017 Wiley Periodicals, Inc.

  13. Flipped classroom improves student learning in health professions education: a meta-analysis.

    Science.gov (United States)

    Hew, Khe Foon; Lo, Chung Kwan

    2018-03-15

    The use of flipped classroom approach has become increasingly popular in health professions education. However, no meta-analysis has been published that specifically examines the effect of flipped classroom versus traditional classroom on student learning. This study examined the findings of comparative articles through a meta-analysis in order to summarize the overall effects of teaching with the flipped classroom approach. We focused specifically on a set of flipped classroom studies in which pre-recorded videos were provided before face-to-face class meetings. These comparative articles focused on health care professionals including medical students, residents, doctors, nurses, or learners in other health care professions and disciplines (e.g., dental, pharmacy, environmental or occupational health). Using predefined study eligibility criteria, seven electronic databases were searched in mid-April 2017 for relevant articles. Methodological quality was graded using the Medical Education Research Study Quality Instrument (MERSQI). Effect sizes, heterogeneity estimates, analysis of possible moderators, and publication bias were computed using the COMPREHENSIVE META-ANALYSIS software. A meta-analysis of 28 eligible comparative studies (between-subject design) showed an overall significant effect in favor of flipped classrooms over traditional classrooms for health professions education (standardized mean difference, SMD = 0.33, 95% confidence interval, CI = 0.21-0.46, p flipped classroom approach was more effective when instructors used quizzes at the start of each in-class session. More respondents reported they preferred flipped to traditional classrooms. Current evidence suggests that the flipped classroom approach in health professions education yields a significant improvement in student learning compared with traditional teaching methods.

  14. Increasing physical activity with mobile devices: a meta-analysis.

    Science.gov (United States)

    Fanning, Jason; Mullen, Sean P; McAuley, Edward

    2012-11-21

    Regular physical activity has established physical and mental health benefits; however, merely one quarter of the U.S. adult population meets national physical activity recommendations. In an effort to engage individuals who do not meet these guidelines, researchers have utilized popular emerging technologies, including mobile devices (ie, personal digital assistants [PDAs], mobile phones). This study is the first to synthesize current research focused on the use of mobile devices for increasing physical activity. To conduct a meta-analysis of research utilizing mobile devices to influence physical activity behavior. The aims of this review were to: (1) examine the efficacy of mobile devices in the physical activity setting, (2) explore and discuss implementation of device features across studies, and (3) make recommendations for future intervention development. We searched electronic databases (PubMed, PsychINFO, SCOPUS) and identified publications through reference lists and requests to experts in the field of mobile health. Studies were included that provided original data and aimed to influence physical activity through dissemination or collection of intervention materials with a mobile device. Data were extracted to calculate effect sizes for individual studies, as were study descriptives. A random effects meta-analysis was conducted using the Comprehensive Meta-Analysis software suite. Study quality was assessed using the quality of execution portion of the Guide to Community Preventative Services data extraction form. Four studies were of "good" quality and seven of "fair" quality. In total, 1351 individuals participated in 11 unique studies from which 18 effects were extracted and synthesized, yielding an overall weight mean effect size of g = 0.54 (95% CI = 0.17 to 0.91, P = .01). Research utilizing mobile devices is gaining in popularity, and this study suggests that this platform is an effective means for influencing physical activity behavior. Our focus

  15. Effects of Coenzyme Q10 on Markers of Inflammation: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Junya Zhai

    Full Text Available Chronic inflammation contributes to the onset and development of metabolic diseases. Clinical evidence has suggested that coenzyme Q10 (CoQ10 has some effects on inflammatory markers. However, these results are equivocal. The aim of this systematic review was to assess the effects of CoQ10 on serum levels of inflammatory markers in people with metabolic diseases.Electronic databases were searched up to February 2016 for randomized controlled trials (RCTs. The outcome parameters were related to inflammatory factors, including interleukin-6 (IL-6, tumor necrosis factor-alpha (TNF-α and C reactive protein (CRP. RevMan software was used for meta-analysis. Meta-regression analysis, Egger line regression test and Begg rank correlation test were performed by STATA software.Nine trials involving 428 subjects were included in this meta-analysis. The results showed that compared with control group, CoQ10 supplementation has significantly improved the serum level of CoQ10 by 1.17μg/ml [MD = 1.17, 95% CI (0.47 to 1.87 μg/ml, I2 = 94%]. Meanwhile, it has significantly decreased TNF-α by 0.45 pg/ml [MD = -0.45, 95% CI (-0.67 to -0.24 pg/ml, I2 = 0%]. No significant difference was observed between CoQ10 and placebo with regard to CRP [MD = -0.21, 95% CI (-0.60 to 0.17 mg/L, I2 = 21%] and IL-6 [MD = -0.89, 95% CI (-1.95 to 0.16 pg/ml, I2 = 84%].CoQ10 supplementation may partly improve the process of inflammatory state. The effects of CoQ10 on inflammation should be further investigated by conducting larger sample size and well-defined trials of long enough duration.

  16. Meta-DiSc: a software for meta-analysis of test accuracy data.

    Science.gov (United States)

    Zamora, Javier; Abraira, Victor; Muriel, Alfonso; Khan, Khalid; Coomarasamy, Arri

    2006-07-12

    Systematic reviews and meta-analyses of test accuracy studies are increasingly being recognised as central in guiding clinical practice. However, there is currently no dedicated and comprehensive software for meta-analysis of diagnostic data. In this article, we present Meta-DiSc, a Windows-based, user-friendly, freely available (for academic use) software that we have developed, piloted, and validated to perform diagnostic meta-analysis. Meta-DiSc a) allows exploration of heterogeneity, with a variety of statistics including chi-square, I-squared and Spearman correlation tests, b) implements meta-regression techniques to explore the relationships between study characteristics and accuracy estimates, c) performs statistical pooling of sensitivities, specificities, likelihood ratios and diagnostic odds ratios using fixed and random effects models, both overall and in subgroups and d) produces high quality figures, including forest plots and summary receiver operating characteristic curves that can be exported for use in manuscripts for publication. All computational algorithms have been validated through comparison with different statistical tools and published meta-analyses. Meta-DiSc has a Graphical User Interface with roll-down menus, dialog boxes, and online help facilities. Meta-DiSc is a comprehensive and dedicated test accuracy meta-analysis software. It has already been used and cited in several meta-analyses published in high-ranking journals. The software is publicly available at http://www.hrc.es/investigacion/metadisc_en.htm.

  17. Negative psychological responses of injury and rehabilitation adherence effects on return to play in competitive athletes: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Ivarsson A

    2017-03-01

    Full Text Available Andreas Ivarsson,1 Ulrika Tranaeus,2,3 Urban Johnson,1 Andreas Stenling 4 1Center of Research on Welfare, Health and Sport, School of Health and Welfare, Halmstad University, Halmstad, 2Performance and Training Unit, The Swedish School of Sport and Health Sciences (GIH, 3Musculoskeletal & Sports Injury Epidemiology Center, IMM, Karolinska Institutet, Stockholm, 4Department of Psychology, Umeå University, Umeå, Sweden Abstract: Previous research offers evidence that psychological factors influence an injured athlete during the rehabilitation process. Our first objective was to conduct a systematic review and meta-analysis of the results from all published studies that examined the relationships among negative affective responses after sport injuries, rehabilitation adherence, and return to play (RTP. The second objective was to use a meta-analytic path analysis to investigate whether an indirect effect existed between negative affective responses and RTP through rehabilitation adherence. This literature review resulted in seven studies providing 14 effect sizes. The results from the meta-analysis showed that negative affective responses had a negative effect on successful RTP, whereas rehabilitation adherence had a positive effect on RTP. The results from the meta-analytic path analysis showed a weak and nonsignificant indirect effect of negative affective responses on RTP via rehabilitation adherence. These results underline the importance of providing supportive environments for injured athletes to increase the chances of successful RTP via a decrease in negative affective responses and increase in rehabilitation adherence. Keywords: affective responses, rehabilitation behaviors, return to play, sport injuries

  18. Robust variance estimation with dependent effect sizes: practical considerations including a software tutorial in Stata and spss.

    Science.gov (United States)

    Tanner-Smith, Emily E; Tipton, Elizabeth

    2014-03-01

    Methodologists have recently proposed robust variance estimation as one way to handle dependent effect sizes in meta-analysis. Software macros for robust variance estimation in meta-analysis are currently available for Stata (StataCorp LP, College Station, TX, USA) and spss (IBM, Armonk, NY, USA), yet there is little guidance for authors regarding the practical application and implementation of those macros. This paper provides a brief tutorial on the implementation of the Stata and spss macros and discusses practical issues meta-analysts should consider when estimating meta-regression models with robust variance estimates. Two example databases are used in the tutorial to illustrate the use of meta-analysis with robust variance estimates. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Effects of anthropogenic heavy metal contamination on litter decomposition in streams – A meta-analysis

    International Nuclear Information System (INIS)

    Ferreira, Verónica; Koricheva, Julia; Duarte, Sofia; Niyogi, Dev K.; Guérold, François

    2016-01-01

    Many streams worldwide are affected by heavy metal contamination, mostly due to past and present mining activities. Here we present a meta-analysis of 38 studies (reporting 133 cases) published between 1978 and 2014 that reported the effects of heavy metal contamination on the decomposition of terrestrial litter in running waters. Overall, heavy metal contamination significantly inhibited litter decomposition. The effect was stronger for laboratory than for field studies, likely due to better control of confounding variables in the former, antagonistic interactions between metals and other environmental variables in the latter or differences in metal identity and concentration between studies. For laboratory studies, only copper + zinc mixtures significantly inhibited litter decomposition, while no significant effects were found for silver, aluminum, cadmium or zinc considered individually. For field studies, coal and metal mine drainage strongly inhibited litter decomposition, while drainage from motorways had no significant effects. The effect of coal mine drainage did not depend on drainage pH. Coal mine drainage negatively affected leaf litter decomposition independently of leaf litter identity; no significant effect was found for wood decomposition, but sample size was low. Considering metal mine drainage, arsenic mines had a stronger negative effect on leaf litter decomposition than gold or pyrite mines. Metal mine drainage significantly inhibited leaf litter decomposition driven by both microbes and invertebrates, independently of leaf litter identity; no significant effect was found for microbially driven decomposition, but sample size was low. Overall, mine drainage negatively affects leaf litter decomposition, likely through negative effects on invertebrates. - Highlights: • A meta-analysis was done to assess the effects of heavy metals on litter decomposition. • Heavy metals significantly and strongly inhibited litter decomposition in streams.

  20. Effectiveness of Secondary Pregnancy Prevention Programs: A Meta-Analysis

    Science.gov (United States)

    Corcoran, Jacqueline; Pillai, Vijayan K.

    2007-01-01

    Because subsequent pregnancy in teen parents often worsens the impact of adolescent parenting; therefore, a common goal of teenage parent programs has been to reduce repeat pregnancy. To examine the impact of this goal, a meta-analysis was conducted on 16 control-comparison group studies that evaluated the effect of teenage pregnancy and parenting…

  1. metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis.

    Science.gov (United States)

    Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

    2016-07-01

    A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness.Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Code is available at https://github.com/aalto-ics-kepaco anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  2. A Meta-Meta-Analysis: Empirical Review of Statistical Power, Type I Error Rates, Effect Sizes, and Model Selection of Meta-Analyses Published in Psychology

    Science.gov (United States)

    Cafri, Guy; Kromrey, Jeffrey D.; Brannick, Michael T.

    2010-01-01

    This article uses meta-analyses published in "Psychological Bulletin" from 1995 to 2005 to describe meta-analyses in psychology, including examination of statistical power, Type I errors resulting from multiple comparisons, and model choice. Retrospective power estimates indicated that univariate categorical and continuous moderators, individual…

  3. Grey literature in meta-analyses.

    Science.gov (United States)

    Conn, Vicki S; Valentine, Jeffrey C; Cooper, Harris M; Rantz, Marilyn J

    2003-01-01

    In meta-analysis, researchers combine the results of individual studies to arrive at cumulative conclusions. Meta-analysts sometimes include "grey literature" in their evidential base, which includes unpublished studies and studies published outside widely available journals. Because grey literature is a source of data that might not employ peer review, critics have questioned the validity of its data and the results of meta-analyses that include it. To examine evidence regarding whether grey literature should be included in meta-analyses and strategies to manage grey literature in quantitative synthesis. This article reviews evidence on whether the results of studies published in peer-reviewed journals are representative of results from broader samplings of research on a topic as a rationale for inclusion of grey literature. Strategies to enhance access to grey literature are addressed. The most consistent and robust difference between published and grey literature is that published research is more likely to contain results that are statistically significant. Effect size estimates of published research are about one-third larger than those of unpublished studies. Unfunded and small sample studies are less likely to be published. Yet, importantly, methodological rigor does not differ between published and grey literature. Meta-analyses that exclude grey literature likely (a) over-represent studies with statistically significant findings, (b) inflate effect size estimates, and (c) provide less precise effect size estimates than meta-analyses including grey literature. Meta-analyses should include grey literature to fully reflect the existing evidential base and should assess the impact of methodological variations through moderator analysis.

  4. Improved meta-analytic methods show no effect of chromium supplements on fasting glucose.

    Science.gov (United States)

    Bailey, Christopher H

    2014-01-01

    The trace mineral chromium has been extensively researched over the years in its role in glucose metabolism. Dietary supplement companies have attempted to make claims that chromium may be able to treat or prevent diabetes. Previous meta-analyses/systematic reviews have indicated that chromium supplementation results in a significant lowering of fasting glucose in diabetics but not in nondiabetics. A meta-analysis was conducted using an alternative measure of effect size, d(ppc2) in order to account for changes in the control group as well as the chromium group. The literature search included MEDLINE, the Cochrane Controlled Trials Register, and previously published article reviews, systematic reviews, and meta-analyses. Included studies were randomized, placebo-controlled trials in the English language with subjects that were nonpregnant adults, both with and without diabetes. Sixteen studies with 809 participants (440 diabetics and 369 nondiabetics) were included in the analysis. Screening for publication bias indicated symmetry of the data. Tests of heterogeneity indicated the use of a fixed-effect model (I² = 0 %). The analysis indicated that there was no significant effect of chromium supplementation in diabetics or nondiabetics, with a weighted average effect size of 0.02 (SE = 0.07), p = 0.787, CI 95 % = -0.12 to 0.16. Chromium supplementation appears to provide no benefits to populations where chromium deficiency is unlikely.

  5. [Effectiveness of acupuncture in postoperative ileus: a systematic review and Meta-analysis].

    Science.gov (United States)

    Cheong, Kah Bik; Zhang, Jiping; Huang, Yong

    2016-06-01

    To conduct a systematic review and Meta-analysis of the effectiveness of acupuncture and common acupoint selection for postoperative ileus (POI). Randomized controlled trials (RCTs) comparing acupuncture and non-acupuncture treatment were identified from the databases PubMed, Cochrane, EBSCO (Academic Source Premier and MEDLINE), Ovid (including Evidence-Based Medicine Reviews), China National Knowledge Infrastructure, and Wanfang Data. The data from eligible studies were extracted and a Meta-analysis performed using a fixed-effects model. Results were expressed as relative risk (RR) for dichotomous data, and 95% CI (confidence intervals) were calculated. Each trial was evaluated using the CONSORT (Consolidated Standards of Reporting Trials) and STRICTA (STandards for Reporting Interventions in Controlled Trials of Acupuncture) guideline . The quality of the study was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Of the 69 studies screened, eight RCTs were included for review. Among these, four RCTs (with a total of 123 patients in the intervention groups and 124 patients in the control groups) met the criteria for Meta-analysis. The Meta-analysis results indicated that acupuncture combined with usual care showed a significantly higher total effective rate than the control condition (usual care) (RR 1.09, 95% CI 1.01, 1.18; P = 0.02). Zusanli (ST 36) and Shangjuxu (ST 37) were the most common acupoints selected. However, the quality of the studies was generally low, as they did not emphasize the use of blinding. The results suggested that acupuncture might be effective in improving POI; however, a definite conclusion could not be drawn because of the low quality of trials. Further large-scale, high-quality randomized clinical trials are needed to validate these findings and to develop a standardized method of treatment. We hope that the present results will lead to improved research, resulting in better

  6. Psychosis as a Risk Factor for Violence to Others: A Meta-Analysis

    Science.gov (United States)

    Douglas, Kevin S.; Guy, Laura S.; Hart, Stephen D.

    2009-01-01

    The potential association between psychosis and violence to others has long been debated. Past research findings are mixed and appear to depend on numerous potential moderators. As such, the authors conducted a quantitative review (meta-analysis) of research on the association between psychosis and violence. A total of 885 effect sizes (odds…

  7. A Meta-Analysis on Antecedents and Outcomes of Detachment from Work

    Science.gov (United States)

    Wendsche, Johannes; Lohmann-Haislah, Andrea

    2017-01-01

    Detachment from work has been proposed as an important non-work experience helping employees to recover from work demands. This meta-analysis (86 publications, k = 91 independent study samples, N = 38,124 employees) examined core antecedents and outcomes of detachment in employee samples. With regard to outcomes, results indicated average positive correlations between detachment and self-reported mental (i.e., less exhaustion, higher life satisfaction, more well-being, better sleep) and physical (i.e., lower physical discomfort) health, state well-being (i.e., less fatigue, higher positive affect, more intensive state of recovery), and task performance (small to medium sized effects). However, average relationships between detachment and physiological stress indicators and work motivation were not significant while associations with contextual performance and creativity were significant, but negative. Concerning work characteristics, as expected, job demands were negatively related and job resources were positively related to detachment (small sized effects). Further, analyses revealed that person characteristics such as negative affectivity/neuroticism (small sized effect) and heavy work investment (medium sized effect) were negatively related to detachment whereas detachment and demographic variables (i.e., age and gender) were not related. Moreover, we found a medium sized average negative relationship between engagement in work-related activities during non-work time and detachment. For most of the examined relationships heterogeneity of effect sizes was moderate to high. We identified study design, samples' gender distribution, and affective valence of work-related thoughts as moderators for some of these aforementioned relationships. The results of this meta-analysis point to detachment as a non-work (recovery) experience that is influenced by work-related and personal characteristics which in turn is relevant for a range of employee outcomes. PMID:28133454

  8. Effect of Surgical Approach on Pulmonary Function in Adolescent Idiopathic Scoliosis Patients: A Systemic Review and Meta-analysis.

    Science.gov (United States)

    Lee, Andy C H; Feger, Mark A; Singla, Anuj; Abel, Mark F

    2016-11-15

    Systemic review and meta-analysis. To analyze the effect of spinal fusion and instrumentation for adolescent idiopathic scoliosis (AIS) on absolute pulmonary function test (PFTs). Pulmonary function is correlated with severity of deformity in AIS patients and studies that have analyzed the effect of spinal fusion and instrumentation on PFTs for AIS have reported inconsistent results. There is a need to analyze the effect of spinal fusion on PFTs with stratification by surgical approach. Our analysis included 22 studies. Cohen's d effect sizes were calculated for absolute PFT outcome measures with 95% confidence intervals (CI). Meta-analyses were performed at each postoperative time frame for six homogeneous surgical approaches: (i) combined anterior release and posterior fusion with instrumentation; (ii) combined video assisted anterior release and posterior fusion with instrumentation without thoracoplasty; (iii) posterior fusion with instrumentation without thoracoplasty; (iv) anterior fusion with instrumentation and without thoracoplasty; (v) video assisted anterior fusion with instrumentation without thoracoplasty; and (vi) any scoliosis surgery with additional thoracoplasty. Anterior spinal fusion with instrumentation, any scoliosis surgery with concomitant thoracoplasty, or video-assisted anterior fusion with instrumentation for AIS had similar absolute PFTs at their 2 year postoperative follow up compared with their preoperative PFTs (effect sizes ranging from -0.2-0.2 with all CI crossing "0"). Posterior spinal fusion with instrumentation (with or without an anterior release) demonstrated small to moderate increases in PFTs 2 years postoperatively (effect sizes ranging from 0.35-0.65 with all CI not crossing "0"). Anterior fusion with instrumentation, regardless of the approach, and any scoliosis surgery with concomitant thoracoplasty do not lead to significant change in pulmonary functions 2 year after surgery. Posterior spinal fusion with instrumentation

  9. Complementary and alternative exercise for fibromyalgia: a meta-analysis

    OpenAIRE

    Mist, Scott; Firestone,Kari; Jones,Kim Dupree

    2013-01-01

    Scott David Mist, Kari Firestone, Kim Dupree Jones Fibromyalgia Research and Treatment Group, School of Nursing, Oregon Health and Science University, Portland, OR, USA Abstract: Complementary and alternative medicine includes a number of exercise modalities, such as tai chi, qigong, yoga, and a variety of lesser-known movement therapies. A meta-analysis of the current literature was conducted estimating the effect size of the different modalities, study quality and bias, and adverse events....

  10. Musicians have better memory than nonmusicians: A meta-analysis.

    Science.gov (United States)

    Talamini, Francesca; Altoè, Gianmarco; Carretti, Barbara; Grassi, Massimo

    2017-01-01

    Several studies have found that musicians perform better than nonmusicians in memory tasks, but this is not always the case, and the strength of this apparent advantage is unknown. Here, we conducted a meta-analysis with the aim of clarifying whether musicians perform better than nonmusicians in memory tasks. Education Source; PEP (WEB)-Psychoanalytic Electronic Publishing; Psychology and Behavioral Science (EBSCO); PsycINFO (Ovid); PubMed; ScienceDirect-AllBooks Content (Elsevier API); SCOPUS (Elsevier API); SocINDEX with Full Text (EBSCO) and Google Scholar were searched for eligible studies. The selected studies involved two groups of participants: young adult musicians and nonmusicians. All the studies included memory tasks (loading long-term, short-term or working memory) that contained tonal, verbal or visuospatial stimuli. Three meta-analyses were run separately for long-term memory, short-term memory and working memory. We collected 29 studies, including 53 memory tasks. The results showed that musicians performed better than nonmusicians in terms of long-term memory, g = .29, 95% CI (.08-.51), short-term memory, g = .57, 95% CI (.41-.73), and working memory, g = .56, 95% CI (.33-.80). To further explore the data, we included a moderator (the type of stimulus presented, i.e., tonal, verbal or visuospatial), which was found to influence the effect size for short-term and working memory, but not for long-term memory. In terms of short-term and working memory, the musicians' advantage was large with tonal stimuli, moderate with verbal stimuli, and small or null with visuospatial stimuli. The three meta-analyses revealed a small effect size for long-term memory, and a medium effect size for short-term and working memory, suggesting that musicians perform better than nonmusicians in memory tasks. Moreover, the effect of the moderator suggested that, the type of stimuli influences this advantage.

  11. Maternal Employment and Children's Achievement in Context: A Meta-Analysis of Four Decades of Research

    Science.gov (United States)

    Goldberg, Wendy A.; Prause, JoAnn; Lucas-Thompson, Rachel; Himsel, Amy

    2008-01-01

    This meta-analysis of 68 studies (770 effect sizes) used random effects models to examine whether children's achievement differed depending on whether their mothers were employed. Four achievement outcomes were emphasized: formal tests of achievement and intellectual functioning, grades, and teacher ratings of cognitive competence. When all…

  12. Inflammation and sarcopenia: A systematic review and meta-analysis.

    Science.gov (United States)

    Bano, Giulia; Trevisan, Caterina; Carraro, Sara; Solmi, Marco; Luchini, Claudio; Stubbs, Brendon; Manzato, Enzo; Sergi, Giuseppe; Veronese, Nicola

    2017-02-01

    Inflammatory cytokines have been shown to prompt muscle wasting, ultimately stimulating protein catabolism and suppressing muscle synthesis. However, the possible association between inflammatory parameters and sarcopenia is poorly understood. We therefore aimed to summarize the current evidence about this topic with a meta-analysis of studies reporting serum inflammatory parameters in patients with sarcopenia vs. people without sarcopenia (controls). An electronic PubMed and Scopus search through to 09/01/2016 and meta-analysis of cross-sectional studies comparing serum levels of inflammatory cytokines between patients with sarcopenia and controls was made, calculating random-effects standardized mean differences (SMDs) ±95% confidence intervals (CIs) as the effect size. Out of 1370 initial hits, 17 studies with a total of 11249 participants (3072 with sarcopenia and 8177 without) were meta-analyzed. Sarcopenic participants had significantly higher levels of CRP (SMD=0.51; 95%CI 0.26, 0.77; psarcopenia versus controls. Sarcopenic people did not have higher levels of TNF-α than controls (SMD=0.28; 95%CI -0.26, 0.83; p=0.31; I 2 =97%). In conclusion, sarcopenia seems to be associated with elevated serum CRP levels; future longitudinal studies are needed to clarify this relationship. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. A quantitative meta-analysis of neurocognitive functioning in posttraumatic stress disorder

    Science.gov (United States)

    Scott, J. Cobb; Matt, Georg E.; Wrocklage, Kristen M.; Crnich, Cassandra; Jordan, Jessica; Southwick, Steven M.; Krystal, John H.; Schweinsburg, Brian C.

    2014-01-01

    Posttraumatic stress disorder (PTSD) is associated with regional alterations in brain structure and function that are hypothesized to contribute to symptoms and cognitive deficits associated with the disorder. We present here the first systematic meta-analysis of neurocognitive outcomes associated with PTSD to examine a broad range of cognitive domains and describe the profile of cognitive deficits, as well as modifying clinical factors and study characteristics. This report is based on data from 60 studies totaling 4,108 participants, including 1,779with PTSD, 1,446 trauma-exposed comparison participants, and 895 healthy comparison participants without trauma exposure. Effect size estimates were calculated using a mixed-effects meta-analysis for nine cognitive domains: attention/working memory, executive functions, verbal learning, verbal memory, visual learning, visual memory, language, speed of information processing, and visuospatial abilities. Analyses revealed significant neurocognitive effects associated with PTSD, although these ranged widely in magnitude, with the largest effect sizes in verbal learning (d =−.62), speed of information processing (d =−.59), attention/working memory (d =−.50), and verbal memory (d =−.46). Effect size estimates were significantly larger in treatment-seeking than community samples and in studies that did not exclude participants with attention-deficit hyperactivity disorder, and effect sizes were affected by between-group IQ discrepancies and the gender composition of the PTSD groups. Our findings indicate that consideration of neuropsychological functioning in attention, verbal memory, and speed of information processing may have important implications for the effective clinical management of persons with PTSD. Results are further discussed in the context of cognitive models of PTSD and the limitations of this literature. PMID:25365762

  14. Gender Differences in Children’s Language: A Meta-Analysis of Slovenian Studies

    Directory of Open Access Journals (Sweden)

    Ljubica Marjanovič-Umek

    2017-06-01

    Full Text Available Child gender has been proved to affect toddlers’/children’s language development in several studies, but its effect was not found to be stable across different ages or various aspects of language ability. The effect of gender on toddler’s, children’s and adolescents’ language ability was examined in the present meta-analysis of ten Slovenian studies (nine cross-sectional studies and one longitudinal study. The ten studies were published between 2004 and 2016 and included a total of 3,657 toddlers, children and adolescents, aged from 8 months to 15 years. The language outcome measures refer to different aspects of language ability, including vocabulary, mean length of utterance, sentence complexity, language expression and comprehension, storytelling ability and metalinguistic awareness. Across the studies, language ability was assessed using different approaches and instruments, most of which were standardised on samples ofSlovenian speaking children. Based on the reported arithmetic means and standard deviations, the effect sizes of gender for each of the included studies were calculated, as well as the average effect size of gender across the different studies. The findings of the meta-analysis showed that the effect size of gender on toddlers’/children’s/adolescents’ language largely depended on their age and the aspect of language measured. The effect sizes increased with children’s increasing age. All significant effects proved to be in favour of girls. The findings were interpreted in relation to the characteristics of language development and social cultural factors that can contribute to gender differences in language ability.

  15. The effect of ginger supplementation on serum C-reactive protein, lipid profile and glycaemia: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Mohsen Mazidi

    2016-11-01

    Full Text Available Aim: To undertake a systematic review and meta-analysis of prospective studies to determine the effect of ginger supplementation on serum C-reactive protein (CRP, lipid profile, and glycaemia. Method: PubMed-MEDLINE, Web of Science, Cochrane Database, and Google Scholar databases were searched (up until July 2016 to identify prospective studies evaluating the impact of ginger supplementation on serum CRP. Random-effects model meta-analysis was used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I2 index. Systematic review registration: CRD42016035973. Results: From a total of 265 entries identified via searches, 9 studies were included in the final selection. The meta-analysis indicated a significant reduction in serum CRP concentrations following ginger supplementation [weighted mean difference (WMD−0.84 mg/L (95% CI −1.38 to −0.31, I2 56.3%]. The WMD for fasting blood glucose and HbA1c was −1.35 mg/dl (95% CI −2.04 to −0.58, I2 12.1% and −1.01 (95% CI −1.28 to −0.72, I2 9.4%, respectively. Moreover, high-density lipoprotein and triglyceride significantly improved after ginger administration [1.16 mg/dl (95% CI 0.52 to 1.08, I2 12.3% and −1.63 mg/dl (95% CI −3.10 to −0.17, I2 8.1%, respectively]. These findings were robust in sensitivity analyses. Random-effects meta-regression revealed that changes in serum CRP levels were independent of the dosage of ginger supplementation (slope −0.20; 95% CI −0.95 to 0.55; p=0.60. Conclusions: This meta-analysis suggests that ginger supplementation significantly reduces serum CRP and improves glycaemia indexes and lipid profile. Randomized control trials with larger sample size and with a longer-term follow-up period should be considered for future investigations.

  16. Effects of Music on Agitation in Dementia: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Siv K. A. Pedersen

    2017-05-01

    Full Text Available Agitation is a common problem in patients suffering from dementia and encompasses a variety of behaviors such as repetitive acts, restlessness, wandering, and aggressive behaviors. Agitation reduces the probability of positive social interaction and increases the psychological and organizational burden. While medical interventions are common, there is need for complementary or alternative methods. Music intervention has been brought forward as a promising method to reduce agitation in dementia. While interventions, target groups and research designs differ, there has so far not been a systematic overview assessing the effect of music intervention for agitation in patients with dementia. A meta-analysis was conducted in order to investigate possible effects of music interventions. Twelve studies met inclusion criteria. Music intervention had a medium overall effect on agitation in dementia, suggesting robust clinical relevance. While the moderate number of studies does not allow for further differentiation between sub-types of music intervention, the sub-group comparisons indicated promising pathways for future systematic reviews. This meta-analysis is the first systematic and quantitative overview supporting clinically and statistically robust effects of music intervention on agitation in dementia. The analysis provides further arguments for this non-pharmacological approach and highlights needs for future systematic research reviews for the investigation of intervention types.

  17. Analysis of the effectiveness of moderate levels of physical activity to reduce the risk of cardiovascular disease, A Meta-analysis

    Directory of Open Access Journals (Sweden)

    Christian Martin Garcia

    2014-12-01

    Full Text Available Objectives: a. The determination of the efficacy of physical activity in reducing the risk of cardiovascular disease; b. The Analysis of the relative changes in the levels of cardiovascular disease risk according to different intensities of physical activity (low-moderate. Methodology: The search was performed for studies with PUBMED data base. Then, the mean effect size of the studies included in the meta-analysis was calculated and Egger's test was applied to rule out any possible publication bias. Upon detection of heterogeneity, we proceeded to an analysis of the moderating variables. Results: A mean effect size of 0.762 (95% confidence interval 0678-0857 was obtained. Then The Egger test was applied which yielded a p-value of 0.67 (CI 0.95, such that the absence of publication bias was confirmed. The analysis of the moderating variables determined that the ensuing years (p = 0.000, 95% CI and the countries of study (p = 0.0096; 95% CI in part explain the heterogeneity detected. Conclusion: It can be concluded that the practice of physical activity at moderate intensities provides a protective effect on the individuals who make physical activity by reducing the risk these individuals to cardiovascular diseases.

  18. A meta-analysis of active video games on health outcomes among children and adolescents.

    Science.gov (United States)

    Gao, Z; Chen, S; Pasco, D; Pope, Z

    2015-09-01

    This meta-analysis synthesizes current literature concerning the effects of active video games (AVGs) on children/adolescents' health-related outcomes. A total of 512 published studies on AVGs were located, and 35 articles were included based on the following criteria: (i) data-based research articles published in English between 1985 and 2015; (ii) studied some types of AVGs and related outcomes among children/adolescents and (iii) had at least one comparison within each study. Data were extracted to conduct comparisons for outcome measures in three separate categories: AVGs and sedentary behaviours, AVGs and laboratory-based exercise, and AVGs and field-based physical activity. Effect size for each entry was calculated with the Comprehensive Meta-Analysis software in 2015. Mean effect size (Hedge's g) and standard deviation were calculated for each comparison. Compared with sedentary behaviours, AVGs had a large effect on health outcomes. The effect sizes for physiological outcomes were marginal when comparing AVGs with laboratory-based exercises. The comparison between AVGs and field-based physical activity had null to moderate effect sizes. AVGs could yield equivalent health benefits to children/adolescents as laboratory-based exercise or field-based physical activity. Therefore, AVGs can be a good alternative for sedentary behaviour and addition to traditional physical activity and sports in children/adolescents. © 2015 World Obesity.

  19. Influence of oral processing on appetite and food intake - A systematic review and meta-analysis.

    Science.gov (United States)

    Krop, Emma M; Hetherington, Marion M; Nekitsing, Chandani; Miquel, Sophie; Postelnicu, Luminita; Sarkar, Anwesha

    2018-06-01

    Food delivers energy, nutrients and a pleasurable experience. Slow eating and prolonged oro-sensory exposure to food during consumption can enhance the processes that promote satiation. This systematic review and meta-analysis investigated the effects of oral processing on subjective measures of appetite (hunger, desire to eat) and objectively measured food intake. The aim was to investigate the influence of oral processing characteristics, specifically "chewing" and "lubrication", on "appetite" and "food intake". A literature search of six databases (Cochrane library, PubMed, Medline, Food Science and Technology Abstracts, Web of Science, Scopus), yielded 12161 articles which were reduced to a set of 40 articles using pre-specified inclusion and exclusion criteria. A further two articles were excluded from the meta-analysis due to missing relevant data. From the remaining 38 papers, detailing 40 unique studies with 70 subgroups, raw data were extracted for meta-analysis (food intake n = 65, hunger n = 22 and desire to eat ratings n = 15) and analyzed using random effects modelling. Oral processing parameters, such as number of chews, eating rate and texture manipulation, appeared to influence food intake markedly but appetite ratings to a lesser extent. Meta-analysis confirmed a significant effect of the direct and indirect aspects of oral processing that were related to chewing on both self-reported hunger (-0.20 effect size, 95% confidence interval CI: -0.30, -0.11), and food intake (-0.28 effect size, 95% CI: -0.36, -0.19). Although lubrication is an important aspect of oral processing, few studies on its effects on appetite have been conducted. Future experiments using standardized approaches should provide a clearer understanding of the role of oral processing, including both chewing and lubrication, in promoting satiety. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. The efficacy of dexamethasone reducing postoperative pain and emesis after total knee arthroplasty: A systematic review and meta-analysis.

    Science.gov (United States)

    Fan, Zhengrui; Ma, Jianxiong; Kuang, Mingjie; Zhang, Lukai; Han, Biao; Yang, Baocheng; Wang, Ying; Ma, Xinlong

    2018-04-01

    Total knee arthroplasty (TKA) is gradually emerging as the treatment of choice for end-stage osteoarthritis. In the past, Perioperative dexamethasone treatment is still a controversial subject in total knee arthroplasty. Therefore, we write this systematic review and meta-analysis to evaluate the efficacy of dexamethasone on pain and recovery after Total knee Arthroplasty. Embase, Pubmed, and Cochrane Library were comprehensively searched. Randomized controlled trials, cohort studies were included in our meta-analysis. Eight studies that compared dexamethasone groups with placebo groups were included in our meta-analysis. The research was reported according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. Randomized controlled trials were included in our meta-analysis. Our study demonstrated that the dexamethasone group was more effective than the placebo group in term of VAS score at 24 h(P meta-analysis demonstrated that dexamethasone decreased postoperative pain, the incidence of POVN, and total opioid consumption effectively which played a critical role in rapid recovery to TKA. However, we still need large sample size, high quality studies to explore the relationship between complications and dose response to give the final conclusion. Copyright © 2018. Published by Elsevier Ltd.

  1. Toxic effect of khat (Catha edulis on memory: Systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Birhane Alem Berihu

    2017-01-01

    Full Text Available Background: People use khat (Catha edulis for its pleasant stimulant effect of physical activity, consciousness, motor, and mental functions. Although there are reports assessing the effect of khat on memory, there was no study based on formal systematic review and meta-analysis. Objective: We have therefore conducted this meta-analysis to determine the level of evidence for the effect of khat (C. edulis Forsk on memory discrepancy. Methods: MEDLINE, Cochrane Library, PubMed, Academic Search Complete, SPORTDiscus, ScienceDirect, Scopus, Web of Science, and Google Scholar were searched to retrieve the papers for this review. Keywords utilized across database search were khat, cat, chat, long-term memory, short-term memory, memory deficit, randomized control trial, and cross-sectional survey. The search was limited to studies in humans and rodents; published in English language. Result: Finding of various studies included in our meta-analysis showed that the effect of acute, and subchronic exposure to khat showed that short-term memory appears to be affected depending on the duration of exposure. However, does not have any effect on long-term memory. Conclusion: Although a number of studies regarding the current topic are limited, the evidenced showed that khat (C. edulis induced memory discrepancy.

  2. Citation analysis of meta-analysis articles on posttraumatic stress disorder.

    Science.gov (United States)

    Liao, Xi-Ming; Chen, Ping-Yan

    2011-04-01

    In the past two decades enormously scientific researches on posttraumatic stress disorder (PTSD) have been undertaken and many related meta-analyses have been published. Citation analysis was used to get comprehensive perspectives of meta-analysis articles (MA articles) on PTSD for the purpose of facilitating the researchers, physicians and policy-makers to understand the PTSD. MA articles on PTSD in any languages from January 1980 to March 2009 were included if they presented meta-analytical methods and received at least one citation recorded in the Web of Science (WoS). Whereas studies, in which any effect sizes of PTSD were not distinguished from other psychological disorders, were excluded. Citations to and by identified MA articles were documented basing on records in WoS. Citation analysis was used to examine distribution patterns of characteristics and citation impact of MA articles on PTSD. Canonical analysis was used to explore the relationship between the characteristics of MA articles and citation impact. Thirty-four MA articles published during 1998 and 2008 were identified and revealed multiple study topics on PTSD: 10 (29.4%) were about epidemiology, 13 (38.2%) about treatment or intervention, 6 (17.6%) about pathophysiology or neurophysiology or neuroendocrine, 3 (8.8%) about childhood and 2 (5.9%) about psychosocial adversity. Two articles cited most frequently with 456 and 145 counts were published in Journal of Consulting and Clinical Psychology by Brewin (2000) and Psychological Bulletin by Ozer (2003), respectively. Mean cited count was 7.48 ± 10.56 and mean age (year 2009 minus article publication year) was (4.24 ± 2.91) years. They had been cited approximately by 67 disciplines and by authors from 42 countries or territories. Characteristics of meta-analysis highly correlated with citation impact and reflected by canonical correlation of 0.899 (P < 0.000 01). The age of MA articles predicted their citation impact. Citation analysis would

  3. The Effectiveness of Cognitive Bias Modification Interventions for Substance Addictions: A Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Ioana A Cristea

    Full Text Available Cognitive bias modification (CBM interventions, presumably targeting automatic processes, are considered particularly promising for addictions. We conducted a meta-analysis examining randomized controlled trials (RCTs of CBM for substance addiction outcomes.Studies were identified through systematic searches in bibliographical databases. We included RCTs of CBM interventions, alone or in combination with other treatments, for any type of addiction. We examined trial risk of bias, publication bias and possible moderators. Effects sizes were computed for post-test and follow-up, using a random-effects model. We grouped outcome measures and reported results for addiction (all related measures, craving and cognitive bias.We identified 25 trials, 18 for alcohol problems, and 7 for smoking. At post-test, there was no significant effect of CBM for addiction, g = 0.08 (95% CI -0.02 to 0.18 or craving, g = 0.05 (95% CI -0.06 to 0.16, but there was a significant, moderate effect on cognitive bias, g = 0.60 (95% CI 0.39 to 0.79. Results were similar for alcohol and smoking outcomes taken separately. Follow-up addiction outcomes were reported in 7 trials, resulting in a small but significant effect of CBM, g = 0.18 (95% CI 0.03 to 0.32. Results for addiction and craving did not differ by substance type, sample type, delivery setting, bias targeted or number of sessions. Risk of bias was high or uncertain in most trials, for most criteria considered. Meta-regression analyses revealed significant inverse relationships between risk of bias and effect sizes for addiction outcomes and craving. The relationship between cognitive bias and respectively addiction ESs was not significant. There was consistent evidence of publication bias in the form of funnel plot asymmetry.Our results cast serious doubts on the clinical utility of CBM interventions for addiction problems, but sounder methodological trials are necessary before this issue can be settled. We found no

  4. The means/side-effect distinction in moral cognition: A meta-analysis.

    Science.gov (United States)

    Feltz, Adam; May, Joshua

    2017-09-01

    Experimental research suggests that people draw a moral distinction between bad outcomes brought about as a means versus a side effect (or byproduct). Such findings have informed multiple psychological and philosophical debates about moral cognition, including its computational structure, its sensitivity to the famous Doctrine of Double Effect, its reliability, and its status as a universal and innate mental module akin to universal grammar. But some studies have failed to replicate the means/byproduct effect especially in the absence of other factors, such as personal contact. So we aimed to determine how robust the means/byproduct effect is by conducting a meta-analysis of both published and unpublished studies (k=101; 24,058 participants). We found that while there is an overall small difference between moral judgments of means and byproducts (standardized mean difference=0.87, 95% CI 0.67-1.06; standardized mean change=0.57, 95% CI 0.44-0.69; log odds ratio=1.59, 95% CI 1.15-2.02), the mean effect size is primarily moderated by whether the outcome is brought about by personal contact, which typically involves the use of personal force. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Effects of catheter-based renal denervation on heart failure with reduced ejection fraction: a systematic review and meta-analysis.

    Science.gov (United States)

    Fukuta, Hidekatsu; Goto, Toshihiko; Wakami, Kazuaki; Ohte, Nobuyuki

    2017-11-01

    Despite the recent advances in the management of heart failure, the mortality of heart failure patients remains high. It is of urgent need to develop new therapy for heart failure. Heart failure is characterized by increased sympathetic activity, and chronic sympathetic activation is involved in the maintenance of the pathological state. Catheter-based renal denervation (RDN) has emerged as an invasive but safe approach that can reduce sympathetic activation. Studies have reported inconsistent results regarding the effect of RDN in heart failure patients due to limited power with small sample sizes. We aimed to conduct a meta-analysis of the effect of RDN on heart failure patients with reduced left ventricular (LV) ejection fraction (EF). An electronic search for studies examining the effect of RDN on LV function in heart failure patients with reduced EF was conducted. Two controlled (80 patients) and 2 uncontrolled studies (21 patients) were included in this meta-analysis. In the pooled analysis, 6 months after RDN, there was a greater increase in EF (weighted mean difference [95% CI] = 8.63 [6.02, 11.24] %) and a greater decrease in LV end-diastolic diameter (-0.58 [-0.83, -0.34] cm) in RDN group than in control group. No serious adverse events such as acute renal artery stenosis and dissection occurred. Our meta-analysis of feasibility studies suggests that RDN may improve LV function in heart failure patients with reduced EF, providing the rationale to conduct next phase trials to confirm the observed potential benefits of RDN.

  6. Meta-analysis of the effectiveness of parenting programmes in improving maternal psychosocial health.

    Science.gov (United States)

    Barlow, Jane; Coren, Esther; Stewart-Brown, Sarah

    2002-03-01

    The purpose of this study was to determine whether group-based parenting programmes are effective in improving maternal psychosocial health. Data sources used were English and non-English language articles published between January 1970 and July 2000, retrieved using a keyword search of a number of biomedical, social science, educational, and general reference electronic databases. Two independent reviewers selected the relevant abstracts and articles. Only controlled trials were included in which participants had been randomly allocated to an experimental and a control group, the latter being a waiting-list, no-treatment or a placebo control group. Studies had to include at least one group-based parenting programme and one standardised instrument measuring maternal psychosocial health. Means, standard deviations, and information regarding study quality were selected from the included studies by two independent reviewers. The treatment effect for each outcome in each study was standardised by dividing the mean difference in post-intervention scores for the intervention and treatment group, by the pooled standard deviation, to produce an effect size. The results were then combined in a meta-analysis using a fixed-effect model. A total of 23 studies met all the inclusion criteria and 17 of these provided sufficient data with which to calculate effect sizes. Fifteen of these studies provided data on the five main outcomes of interest: depression, anxiety/stress, self-esteem, social support, and relationship with partner. The meta-analyses show statistically significant results favouring the intervention group for depression (-0.3, 95% confidence interval [CI] = -0.4 to -0.1), anxiety/stress (-0.5, 95% CI = -0.7 to -0.3), self-esteem (-0.4, 95% CI = -0.6 to -0.1), and relationship with partner (-0.4, 95% CI = -0.7 to -0.2). However, the meta-analysis of the social support data showed no evidence of effectiveness (-0.04, 95% CI = -0.3 to 0.2). Follow-up data were

  7. A Meta-Analysis of the Impact of Stars on Economic Success of Movies

    DEFF Research Database (Denmark)

    Hofmann, Julian

    experts continuously debate whether the movie industry’s enormous investments in stars pay off. Our study provides a meta-analysis of the relationship between star power and movies’ success based on 35 primary studies. A key finding is that the mean effect size for star power is significantly higher than...

  8. A Meta-Analysis of Factors Influencing the Development of Trust in Automation: Implications for Understanding Autonomy in Future Systems.

    Science.gov (United States)

    Schaefer, Kristin E; Chen, Jessie Y C; Szalma, James L; Hancock, P A

    2016-05-01

    We used meta-analysis to assess research concerning human trust in automation to understand the foundation upon which future autonomous systems can be built. Trust is increasingly important in the growing need for synergistic human-machine teaming. Thus, we expand on our previous meta-analytic foundation in the field of human-robot interaction to include all of automation interaction. We used meta-analysis to assess trust in automation. Thirty studies provided 164 pairwise effect sizes, and 16 studies provided 63 correlational effect sizes. The overall effect size of all factors on trust development was ḡ = +0.48, and the correlational effect was [Formula: see text]  = +0.34, each of which represented medium effects. Moderator effects were observed for the human-related (ḡ  = +0.49; [Formula: see text] = +0.16) and automation-related (ḡ = +0.53; [Formula: see text] = +0.41) factors. Moderator effects specific to environmental factors proved insufficient in number to calculate at this time. Findings provide a quantitative representation of factors influencing the development of trust in automation as well as identify additional areas of needed empirical research. This work has important implications to the enhancement of current and future human-automation interaction, especially in high-risk or extreme performance environments. © 2016, Human Factors and Ergonomics Society.

  9. Methodological characteristics and treatment effect sizes in oral health randomised controlled trials: Is there a relationship? Protocol for a meta-epidemiological study.

    Science.gov (United States)

    Saltaji, Humam; Armijo-Olivo, Susan; Cummings, Greta G; Amin, Maryam; Flores-Mir, Carlos

    2014-02-25

    It is fundamental that randomised controlled trials (RCTs) are properly conducted in order to reach well-supported conclusions. However, there is emerging evidence that RCTs are subject to biases which can overestimate or underestimate the true treatment effect, due to flaws in the study design characteristics of such trials. The extent to which this holds true in oral health RCTs, which have some unique design characteristics compared to RCTs in other health fields, is unclear. As such, we aim to examine the empirical evidence quantifying the extent of bias associated with methodological and non-methodological characteristics in oral health RCTs. We plan to perform a meta-epidemiological study, where a sample size of 60 meta-analyses (MAs) including approximately 600 RCTs will be selected. The MAs will be randomly obtained from the Oral Health Database of Systematic Reviews using a random number table; and will be considered for inclusion if they include a minimum of five RCTs, and examine a therapeutic intervention related to one of the recognised dental specialties. RCTs identified in selected MAs will be subsequently included if their study design includes a comparison between an intervention group and a placebo group or another intervention group. Data will be extracted from selected trials included in MAs based on a number of methodological and non-methodological characteristics. Moreover, the risk of bias will be assessed using the Cochrane Risk of Bias tool. Effect size estimates and measures of variability for the main outcome will be extracted from each RCT included in selected MAs, and a two-level analysis will be conducted using a meta-meta-analytic approach with a random effects model to allow for intra-MA and inter-MA heterogeneity. The intended audiences of the findings will include dental clinicians, oral health researchers, policymakers and graduate students. The aforementioned will be introduced to the findings through workshops, seminars, round

  10. Perceptions of Duchenne and non-Duchenne smiles: A meta-analysis.

    Science.gov (United States)

    Gunnery, Sarah D; Ruben, Mollie A

    2016-01-01

    A meta-analysis was conducted to compare perceptions of Duchenne smiles, smiles that include activation of the cheek raiser muscle that creates crow's feet around the eyes, with perceptions of non-Duchenne smiles, smiles without cheek raiser activation. In addition to testing the overall effect, moderator analyses were conducted to test how methodological, stimulus-specific and perceiver-specific differences between studies predicted the overall effect size. The meta-analysis found that, overall, Duchenne smiles and people producing Duchenne smiles are rated more positively (i.e., authentic, genuine, real, attractive, trustworthy) than non-Duchenne smiles and people producing non-Duchenne smiles. The difference between Duchenne and non-Duchenne smiles was greater when the stimuli were videos rather than photographs, when smiles were elicited naturally rather than through posing paradigms and when Duchenne and non-Duchenne smiles were not matched for intensity of the lip corner puller in addition to other perceiver and methodological moderators.

  11. Statin treatment and functional outcome after ischemic stroke: case-control and meta-analysis.

    Science.gov (United States)

    Biffi, Alessandro; Devan, William J; Anderson, Christopher D; Cortellini, Lynelle; Furie, Karen L; Rosand, Jonathan; Rost, Natalia S

    2011-05-01

    Multiple studies suggest that statin use before acute ischemic stroke is associated with improved functional outcome. However, available evidence is conflicting, and several published reports are limited by small sample sizes. We therefore investigated the effect of antecedent use of statins on stroke outcome by performing a meta-analysis of all results from published studies as well as our own unpublished data. We performed a systematic literature search and meta-analysis of studies investigating the association between prestroke statin use and clinical outcome and included additional data from 126 prestroke statin users and 767 nonusers enrolled at our institution. A total of 12 studies, comprising 2013 statin users and 9682 nonusers, was meta-analyzed using a random effects model. We also meta-analyzed results for individual Trial of ORG 10172 in Acute Stroke Treatment stroke subtypes to determine whether the effect of statin use differed across subtypes using the Breslow-Day test. Meta-analysis of all available data identified an association between prestroke statin use and improved functional outcome (OR, 1.62; 95% CI, 1.39 to 1.88), but we uncovered evidence of publication bias. The effect of statin use on functional outcome was found to be larger for small vessel strokes compared with other subtypes (Breslow-Day P=0.008). Antecedent use of statins is associated with improved outcome in patients with acute ischemic stroke. This association appears to be stronger in patients with small vessel stroke subtype. However, evidence of publication bias in the existing literature suggests these findings should be interpreted with caution.

  12. A meta-analysis of peripheral blood nerve growth factor levels in patients with schizophrenia.

    Science.gov (United States)

    Qin, X-Y; Wu, H-T; Cao, C; Loh, Y P; Cheng, Y

    2017-09-01

    Neurotrophins particularly brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are crucial modulators in the neurodevelopment and maintenance of central and peripheral nervous systems. Neurotrophin hypothesis of schizophrenia (SCZ) postulated that the changes in the brains of SCZ patients are the result of disturbances of developing processes involving neurotrophic factors. This hypothesis was mainly supported by the abnormal regulation of BDNF in SCZ, especially the decreased peripheral blood BDNF levels in SCZ patients validated by several meta-analyses. However, the regulation of NGF in SCZ remains unclear because of the inconsistent findings from the clinical studies. Therefore, we undertook, to the best of our knowledge, the first systematic review with a meta-analysis to quantitatively summarize the peripheral blood NGF data in SCZ patients compared with healthy control (HC) subjects. A systematic search of Pubmed, PsycINFO and Web of Science identified 13 articles encompassing a sample of 1693 individuals for the meta-analysis. Random-effects meta-analysis showed that patients with SCZ had significantly decreased peripheral blood levels of NGF when compared with the HC subjects (Hedges's g=-0.633, 95% confidence interval (CI)=-0.948 to -0.318, Pmeta-regression analyses showed that age, gender and sample size had no moderating effects on the outcome of the meta-analysis, whereas disease severity might be a confounding factor for the meta-analysis. These results demonstrated that patients with SCZ are accompanied by the decreased peripheral blood NGF levels, strengthening the clinical evidence of an abnormal neurotrophin profile in the patients with SCZ.

  13. Effects of condom social marketing on condom use in developing countries: a systematic review and meta-analysis, 1990-2010.

    Science.gov (United States)

    Sweat, Michael D; Denison, Julie; Kennedy, Caitlin; Tedrow, Virginia; O'Reilly, Kevin

    2012-08-01

    To examine the relationship between condom social marketing programmes and condom use. Standard systematic review and meta-analysis methods were followed. The review included studies of interventions in which condoms were sold, in which a local brand name(s) was developed for condoms, and in which condoms were marketed through a promotional campaign to increase sales. A definition of intervention was developed and standard inclusion criteria were followed in selecting studies. Data were extracted from each eligible study, and a meta-analysis of the results was carried out. Six studies with a combined sample size of 23,048 met the inclusion criteria. One was conducted in India and five in sub-Saharan Africa. All studies were cross-sectional or serial cross-sectional. Three studies had a comparison group, although all lacked equivalence in sociodemographic characteristics across study arms. All studies randomly selected participants for assessments, although none randomly assigned participants to intervention arms. The random-effects pooled odds ratio for condom use was 2.01 (95% confidence interval, CI: 1.42-2.84) for the most recent sexual encounter and 2.10 (95% CI: 1.51-2.91) for a composite of all condom use outcomes. Tests for heterogeneity yielded significant results for both meta-analyses. The evidence base for the effect of condom social marketing on condom use is small because few rigorous studies have been conducted. Meta-analyses showed a positive and statistically significant effect on increasing condom use, and all individual studies showed positive trends. The cumulative effect of condom social marketing over multiple years could be substantial. We strongly encourage more evaluations of these programmes with study designs of high rigour.

  14. Effects of group reminiscence on elderly depression: A meta-analysis

    OpenAIRE

    Dan Song; Qin Shen; Tu-Zhen Xu; Qiu-Hua Sun

    2014-01-01

    Background/purpose: The present meta-analysis was performed to evaluate the effectiveness of group reminiscence on depression in elderly patients. Methods: Published and unpublished randomised controlled trials that assessed the effects of group reminiscence on depression in elderly patients were systematically reviewed using multiple electronic databases. Relative risks for dichotomous data and weighted mean differences for continuous data were calculated with 95% confidence intervals. ...

  15. Meta-Analysis of the Reasoned Action Approach (RAA) to Understanding Health Behaviors.

    Science.gov (United States)

    McEachan, Rosemary; Taylor, Natalie; Harrison, Reema; Lawton, Rebecca; Gardner, Peter; Conner, Mark

    2016-08-01

    Reasoned action approach (RAA) includes subcomponents of attitude (experiential/instrumental), perceived norm (injunctive/descriptive), and perceived behavioral control (capacity/autonomy) to predict intention and behavior. To provide a meta-analysis of the RAA for health behaviors focusing on comparing the pairs of RAA subcomponents and differences between health protection and health-risk behaviors. The present research reports a meta-analysis of correlational tests of RAA subcomponents, examination of moderators, and combined effects of subcomponents on intention and behavior. Regressions were used to predict intention and behavior based on data from studies measuring all variables. Capacity and experiential attitude had large, and other constructs had small-medium-sized correlations with intention; all constructs except autonomy were significant independent predictors of intention in regressions. Intention, capacity, and experiential attitude had medium-large, and other constructs had small-medium-sized correlations with behavior; intention, capacity, experiential attitude, and descriptive norm were significant independent predictors of behavior in regressions. The RAA subcomponents have utility in predicting and understanding health behaviors.

  16. Exercise-associated DNA methylation change in skeletal muscle and the importance of imprinted genes: a bioinformatics meta-analysis.

    Science.gov (United States)

    Brown, William M

    2015-12-01

    Epigenetics is the study of processes--beyond DNA sequence alteration--producing heritable characteristics. For example, DNA methylation modifies gene expression without altering the nucleotide sequence. A well-studied DNA methylation-based phenomenon is genomic imprinting (ie, genotype-independent parent-of-origin effects). We aimed to elucidate: (1) the effect of exercise on DNA methylation and (2) the role of imprinted genes in skeletal muscle gene networks (ie, gene group functional profiling analyses). Gene ontology (ie, gene product elucidation)/meta-analysis. 26 skeletal muscle and 86 imprinted genes were subjected to g:Profiler ontology analysis. Meta-analysis assessed exercise-associated DNA methylation change. g:Profiler found four muscle gene networks with imprinted loci. Meta-analysis identified 16 articles (387 genes/1580 individuals) associated with exercise. Age, method, sample size, sex and tissue variation could elevate effect size bias. Only skeletal muscle gene networks including imprinted genes were reported. Exercise-associated effect sizes were calculated by gene. Age, method, sample size, sex and tissue variation were moderators. Six imprinted loci (RB1, MEG3, UBE3A, PLAGL1, SGCE, INS) were important for muscle gene networks, while meta-analysis uncovered five exercise-associated imprinted loci (KCNQ1, MEG3, GRB10, L3MBTL1, PLAGL1). DNA methylation decreased with exercise (60% of loci). Exercise-associated DNA methylation change was stronger among older people (ie, age accounted for 30% of the variation). Among older people, genes exhibiting DNA methylation decreases were part of a microRNA-regulated gene network functioning to suppress cancer. Imprinted genes were identified in skeletal muscle gene networks and exercise-associated DNA methylation change. Exercise-associated DNA methylation modification could rewind the 'epigenetic clock' as we age. CRD42014009800. Published by the BMJ Publishing Group Limited. For permission to use (where

  17. Effect of oxandrolone therapy on adult height in Turner syndrome patients treated with growth hormone: a meta-analysis.

    Science.gov (United States)

    Sheanon, Nicole M; Backeljauw, Philippe F

    2015-01-01

    Turner syndrome is a chromosomal abnormality in which there is complete or partial absence of the X chromosome. Turner syndrome effects 1 in every 2000 live births. Short stature is a cardinal feature of Turner Syndrome and the standard treatment is recombinant human growth hormone. When growth hormone is started at an early age a normal adult height can be achieved. With delayed diagnosis young women with Turner Syndrome may not reach a normal height. Adjuvant therapy with oxandrolone is used but there is no consensus on the optimal timing of treatment, the duration of treatment and the long term adverse effects of treatment. The objective of this review and meta-analysis is to examine the effect of oxandrolone on adult height in growth hormone treated Turner syndrome patients. Eligible trials were identified by a literature search using the terms: Turner syndrome, oxandrolone. The search was limited to English language randomized-controlled trials after 1980. Twenty-six articles were reviewed and four were included in the meta-analysis. A random effects model was used to calculate an effect size and confidence interval. The pooled effect size of 2.0759 (95 % CI 0.0988 to 4.0529) indicates that oxandrolone has a positive effect on adult height in Turner syndrome when combined with growth hormone therapy. In conclusion, the addition of oxandrolone to growth hormone therapy for treatment of short stature in Turner syndrome improves adult height. Further studies are warranted to investigate if there is a subset of Turner syndrome patients that would benefit most from growth hormone plus oxandrolone therapy, and to determine the optimal timing and duration of such therapy.

  18. The Strength and Drivers of Bird-Mediated Selection on Fruit Crop Size: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Facundo X. Palacio

    2018-02-01

    Full Text Available In seed-dispersal mutualisms, the number of fruit a plant displays is a key trait, as it acts as a signal for seed dispersers that entails fruit removal and exportation of reproductive units (fruit crop size hypothesis. Although this hypothesis has gained general acceptance, forces driving the shape and strength of natural selection exerted by birds on fruit crop size remains an unresolved matter. Here, we propose that ecological filters promoting high functional equivalence of interacting partners (similar functional roles translate into similar selection pressures on fruit crop size, enhancing selection strength on this trait. We performed a meta-analysis on 50 seed-dispersal systems to test the hypothesis that frugivorous birds exert positive selection pressure on fruit crop size, and to assess whether different factors expected to act as filters (fruit diameter, fruit type, fruiting season length, bird functional groups, and latitude influence phenotypic selection regimes on this trait. Birds promote larger fruit crop sizes as a general pattern in nature. Short fruiting seasons and a high proportion of species belonging to the same functional group showed higher selection strength on fruit crop size. Also, selection strength on fruit crop size increased for large-fruited species and toward the tropics. Our results support the hypothesis that fruit crop size represents a conspicuous signal advertising the amount of reward to visually driven interacting partners, and that both plant and bird traits, as well as environmental factors, drive selection strength on fruit display traits. Furthermore, our results suggest that the relationship among forces impinged by phenology and frugivore functional roles may be key to understand their evolutionary stability.

  19. Digital Simulation-Based Training: A Meta-Analysis

    Science.gov (United States)

    Gegenfurtner, Andreas; Quesada-Pallarès, Carla; Knogler, Maximilian

    2014-01-01

    This study examines how design characteristics in digital simulation-based learning environments moderate self-efficacy and transfer of learning. Drawing on social cognitive theory and the cognitive theory of multimedia learning, the meta-analysis psychometrically cumulated k?=?15 studies of 25 years of research with a total sample size of…

  20. Volunteering by older adults and risk of mortality: a meta-analysis.

    Science.gov (United States)

    Okun, Morris A; Yeung, Ellen WanHeung; Brown, Stephanie

    2013-06-01

    Organizational volunteering has been touted as an effective strategy for older adults to help themselves while helping others. Extending previous reviews, we carried out a meta-analysis of the relation between organizational volunteering by late-middle-aged and older adults (minimum age = 55 years old) and risk of mortality. We focused on unadjusted effect sizes (i.e., bivariate relations), adjusted effect sizes (i.e., controlling for other variables such as health), and interaction effect sizes (e.g., the joint effect of volunteering and religiosity). For unadjusted effect sizes, on average, volunteering reduced mortality risk by 47%, with a 95% confidence interval ranging from 38% to 55%. For adjusted effect sizes, on average, volunteering reduced mortality risk by 24%, with a 95% confidence interval ranging from 16% to 31%. For interaction effect sizes, we found preliminary support that as public religiosity increases, the inverse relation between volunteering and mortality risk becomes stronger. The discussion identifies several unresolved issues and directions for future research. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  1. Meta-Analyst: software for meta-analysis of binary, continuous and diagnostic data

    Directory of Open Access Journals (Sweden)

    Schmid Christopher H

    2009-12-01

    Full Text Available Abstract Background Meta-analysis is increasingly used as a key source of evidence synthesis to inform clinical practice. The theory and statistical foundations of meta-analysis continually evolve, providing solutions to many new and challenging problems. In practice, most meta-analyses are performed in general statistical packages or dedicated meta-analysis programs. Results Herein, we introduce Meta-Analyst, a novel, powerful, intuitive, and free meta-analysis program for the meta-analysis of a variety of problems. Meta-Analyst is implemented in C# atop of the Microsoft .NET framework, and features a graphical user interface. The software performs several meta-analysis and meta-regression models for binary and continuous outcomes, as well as analyses for diagnostic and prognostic test studies in the frequentist and Bayesian frameworks. Moreover, Meta-Analyst includes a flexible tool to edit and customize generated meta-analysis graphs (e.g., forest plots and provides output in many formats (images, Adobe PDF, Microsoft Word-ready RTF. The software architecture employed allows for rapid changes to be made to either the Graphical User Interface (GUI or to the analytic modules. We verified the numerical precision of Meta-Analyst by comparing its output with that from standard meta-analysis routines in Stata over a large database of 11,803 meta-analyses of binary outcome data, and 6,881 meta-analyses of continuous outcome data from the Cochrane Library of Systematic Reviews. Results from analyses of diagnostic and prognostic test studies have been verified in a limited number of meta-analyses versus MetaDisc and MetaTest. Bayesian statistical analyses use the OpenBUGS calculation engine (and are thus as accurate as the standalone OpenBUGS software. Conclusion We have developed and validated a new program for conducting meta-analyses that combines the advantages of existing software for this task.

  2. Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

    Science.gov (United States)

    Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

    2016-09-01

    Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship.

  3. Systematic review and meta-analysis of the effects of football heading.

    Science.gov (United States)

    Kontos, Anthony P; Braithwaite, Rock; Chrisman, Sara P D; McAllister-Deitrick, Jamie; Symington, Larissa; Reeves, Valerie L; Collins, Michael W

    2017-08-01

    The objective of this study was to provide a meta-analysis examining the effects of football heading. Meta-analytical review on football heading effects on neurocognitive performance, cognition and symptom reports. Combinations of the key terms were entered into the following electronic database search engines: Cochrane Libraries, PyscARTICLE, PyscINFO, PubMed, ProQuest, SPORTDiscus and Web of Science on 7 July 2016. The following inclusion criteria were used to determine eligibility for studies: (1) the study examined and reported on soccer athletes; (2) the population's age, sex and sport position was described; (3) cognitive function, symptoms, balance or other outcomes were quantitatively measured; (4) football heading exposure was quantitatively measured between at least two groups and (5) the study was written in the English language after December 1979. The literature search process identified 467 unique studies. After applying exclusion criteria, 28 studies remained. Included studies had a total of 2288 participants (female participants =933, male participants =1355), aged 13-70 years. The overall results of random effects modelling of football heading were found to be inconclusive across all outcomes, groups and time points. No moderating variables related to methodological, sample or study characteristics were supported in the analysis; age was a potential moderating variable. We provide the first meta-analytical review of football heading effects aggregated from multiple studies and extended findings from a recent systematic review of the effects of football heading. Our analysis indicates no overall effect for heading a football on adverse outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  4. Self-reported interoceptive deficits in eating disorders: A meta-analysis of studies using the eating disorder inventory.

    Science.gov (United States)

    Jenkinson, Paul M; Taylor, Lauren; Laws, Keith R

    2018-07-01

    An impairment of the ability to sense the physiological condition of the body - interoception - has long been proposed as central to the onset and maintenance of eating disorders. More recent attention to this topic has generally indicated the presence of interoceptive deficits in individuals with an eating disorder diagnosis; however, possible links with specific diagnosis, BMI, age, illness duration, depression, and alexithymia remain unclear from individual studies. This meta-analysis aimed to provide a necessary quantitative overview of self-reported interoceptive deficits in eating disorder populations, and the relationship between these deficits and the previously mentioned factors. Using a random effects model, our meta-analysis assessed the magnitude of differences in interoceptive abilities as measured using the Eating Disorder Inventory in 41 samples comparing people with eating disorders (n = 4308) and healthy controls (n = 3459). Follow-up and moderator analysis was conducted, using group comparisons and meta-regressions. We report a large pooled effect size of 1.62 for eating disorders with some variation between diagnostic groups. Further moderator analysis showed that BMI, age and alexithymia were significant predictors of overall effect size. This meta-analysis is the first to confirm that large interoceptive deficits occur in a variety of eating disorders and crucially, in those who have recovered. These deficits may be useful in identifying and distinguishing eating disorders. Future research needs to consider both objective and subjective measures of interoception across different types of eating disorders and may fruitfully examine interoception as a possible endophenotype and target for treatment. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. A Meta-analysis of the Effectiveness of Interactive Middle School Cannabis Prevention Programs.

    Science.gov (United States)

    Lize, Steven E; Iachini, Aidyn L; Tang, Weizhou; Tucker, Joshua; Seay, Kristen D; Clone, Stephanie; DeHart, Dana; Browne, Teri

    2017-01-01

    This meta-analysis examines the effectiveness of interactive middle school-based drug prevention programs on adolescent cannabis use in North America, as well as program characteristics that could moderate these effects. Interactive programs, compared to more didactic, lecture style programs, involve participants in skill-building activities and focus on interaction among participants. A systematic literature search was conducted for English-language studies from January 1998 to March 2014. Studies included evaluations using random assignment or a quasi-experimental design of interactive school-based substance use prevention programs delivered to adolescents (aged 12-14) in North American middle schools (grades 6-8). Data were extracted using a coding protocol. The outcomes of interest were post-treatment cannabis use, intent to use, and refusal skills compared across intervention and control groups. Effect sizes (Cohen's d) were calculated from continuous measures, and dichotomous measures were converted to the d index. A total of 30 studies yielding 23 independent samples were included. The random effects pooled effect size for cannabis use (k = 21) was small ([Formula: see text]= -0.07, p prevention programs. The pooled effect sizes for intention to use (k = 3) and refusal skills (k = 3) were not significant. Moderator analyses indicated significant differences in program effectiveness between instructor types, with teachers found to be most effective ([Formula: see text]= -0.08, p = 0.02). The findings provide further support for the use of interactive school-based programs to prevent cannabis use among middle school students in North America.

  6. Affective empathy in schizophrenia: a meta-analysis.

    Science.gov (United States)

    Bonfils, Kelsey A; Lysaker, Paul H; Minor, Kyle S; Salyers, Michelle P

    2016-08-01

    Affective empathy, or the emotional response one has to the experiences or emotional states of others, contributes to relationship-maintaining behaviors and is key in fostering social connections, yet no work has synthesized the body of literature for people with schizophrenia. The aim of the present meta-analysis was to determine the extent to which those diagnosed with schizophrenia experience deficits in affective empathy. A literature search was conducted of studies examining empathy. Data were analyzed using a random effects meta-analytic model with Hedges' g standardized mean difference effect size. Individuals with schizophrenia exhibited significant, medium deficits in affective empathy (k=37). Measurement type moderated the affective empathy deficit such that performance-based measures showed larger schizophrenia group deficits than self-report measures. Consistent, significant deficits in affective empathy were found comparing people with schizophrenia to healthy controls, especially when using performance-based assessments. The medium effect suggests an important role for empathy in the realm of social cognitive research, and points to the need for further investigation of measurement techniques and associations with functional outcomes. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Cumulative Effects of Concussion History on Baseline Computerized Neurocognitive Test Scores: Systematic Review and Meta-analysis.

    Science.gov (United States)

    Alsalaheen, Bara; Stockdale, Kayla; Pechumer, Dana; Giessing, Alexander; He, Xuming; Broglio, Steven P

    It is unclear whether individuals with a history of single or multiple clinically recovered concussions exhibit worse cognitive performance on baseline testing compared with individuals with no concussion history. To analyze the effects of concussion history on baseline neurocognitive performance using a computerized neurocognitive test. PubMed, CINAHL, and psycINFO were searched in November 2015. The search was supplemented by a hand search of references. Studies were included if participants completed the Immediate Post-concussion Assessment and Cognitive Test (ImPACT) at baseline (ie, preseason) and if performance was stratified by previous history of single or multiple concussions. Systematic review and meta-analysis. Level 2. Sample size, demographic characteristics of participants, as well as performance of participants on verbal memory, visual memory, visual-motor processing speed, and reaction time were extracted from each study. A random-effects pooled meta-analysis revealed that, with the exception of worsened visual memory for those with 1 previous concussion (Hedges g = 0.10), no differences were observed between participants with 1 or multiple concussions compared with participants without previous concussions. With the exception of decreased visual memory based on history of 1 concussion, history of 1 or multiple concussions was not associated with worse baseline cognitive performance.

  8. Dialectical behavior therapy for borderline personality disorder: a meta-analysis using mixed-effects modeling.

    Science.gov (United States)

    Kliem, Sören; Kröger, Christoph; Kosfelder, Joachim

    2010-12-01

    At present, the most frequently investigated psychosocial intervention for borderline personality disorder (BPD) is dialectical behavior therapy (DBT). We conducted a meta-analysis to examine the efficacy and long-term effectiveness of DBT. Systematic bibliographic research was undertaken to find relevant literature from online databases (PubMed, PsycINFO, PsychSpider, Medline). We excluded studies in which patients with diagnoses other than BPD were treated, the treatment did not comprise all components specified in the DBT manual or in the suggestions for inpatient DBT programs, patients failed to be diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, and the intervention group comprised fewer than 10 patients. Using a mixed-effect hierarchical modeling approach, we calculated global effect sizes and effect sizes for suicidal and self-injurious behaviors. Calculations of postintervention global effect sizes were based on 16 studies. Of these, 8 were randomized controlled trials (RCTs), and 8 were neither randomized nor controlled (nRCT). The dropout rate was 27.3% pre- to posttreatment. A moderate global effect and a moderate effect size for suicidal and self-injurious behaviors were found, when including a moderator for RCTs with borderline-specific treatments. There was no evidence for the influence of other moderators (e.g., quality of studies, setting, duration of intervention). A small impairment was shown from posttreatment to follow-up, including 5 RCTs only. Future research should compare DBT with other active borderline-specific treatments that have also demonstrated their efficacy using several long-term follow-up assessment points. (c) 2010 APA, all rights reserved.

  9. The effectiveness of oral appliances for obstructive sleep apnea syndrome: A meta-analysis.

    Science.gov (United States)

    Zhu, Yafen; Long, Hu; Jian, Fan; Lin, Jianchang; Zhu, Jingyi; Gao, Meiya; Lai, Wenli

    2015-12-01

    To evaluate the effectiveness of oral appliances (OAs) for managing patients with obstructive sleep apnea (OSA). PubMed, Embase, Web of Science, CENTRAL and SIGLE were electronically searched from January 1980 to September 2015 for randomized or nonrandomized controlled trials that assessed the effectiveness of OAs on OSAS. The processes of study search, selection, data extraction, assessment of risk of bias and evaluation of evidence quality were conducted independently by two reviewer authors. Meta-analyses were performed in Review Manager 5, Stata11.0 and StatsDirect 2.7.9. Finally, we included 17 eligible studies which compared OAs and placebo or blank control. Six outcomes were assessed in this meta-analysis, i.e., apnea hypopnea index (AHI), respiratory arousal index (RAI), minimum oxygen saturation(MinSaO2), rapid eye movement (REM) sleep, sleep efficiency and Epworth Sleepiness Scale (ESS). Meta-analysis revealed that the pooled mean differences were -10.26 [95% CI: (-12.59, -7.93)], -9.03 [95% CI: (-11.89, -6.17)], 3.08 [95% CI: (1.97, 4.19)], 0.36 [95% CI: (-0.30, 1.02)], 1.34 [95% CI: (-0.05, 2.73)] and -1.76 [95% CI: (-2.57, -0.94)], respectively. The sensitivity analysis and subgroup analysis displayed generally robust results except for MinSaO2, REM sleep and sleep efficiency. Furthermore, publication bias was detected in RAI and MinSaO2. The available evidence indicates benefits in respiration and sleep quality with oral appliances as compared to placebo devices or blank control, while we cannot determine its effectiveness in sleep efficiency and sleep architecture alterations. However, due to low evidence quality as revealed by GRADE, this finding should be interpreted with caution. Through critical meta-analyses, we found that oral appliances are effective in respiration improving and sleep quality. The existing evidence supports the employment of OAs as a recommendable treatment option for OSA. This meta-analysis helps to direct clinical practice

  10. Effect of low-frequency rTMS on aphasia in stroke patients: a meta-analysis of randomized controlled trials.

    Directory of Open Access Journals (Sweden)

    Cai-Li Ren

    Full Text Available Small clinical trials have reported that low-frequency repetitive transcranial magnetic stimulation (rTMS might improve language recovery in patients with aphasia after stroke. However, no systematic reviews or meta-analyses studies have investigated the effect of rTMS on aphasia. The objective of this study was to perform a meta-analysis of studies that explored the effects of low-frequency rTMS on aphasia in stroke patients.We searched PubMed, CENTRAL, Embase, CINAHL, ScienceDirect, and Journals@Ovid for randomized controlled trials published between January 1965 and October 2013 using the keywords "aphasia OR language disorders OR anomia OR linguistic disorders AND repetitive transcranial magnetic stimulation OR rTMS". We used fixed- and random-effects models to estimate the standardized mean difference (SMD and a 95% CI for the language outcomes.Seven eligible studies involving 160 stroke patients were identified in this meta-analysis. A significant effect size of 1.26 was found for the language outcome severity of impairment (95% CI = 0.80 to 1.71 without heterogeneity (I2 = 0%, P = 0.44. Further analyses demonstrated prominent effects for the naming subtest (SMD = 0.52, 95% CI = 0.18 to 0.87, repetition (SMD = 0.54, 95% CI = 0.16 to 0.92, writing (SMD = 0.70, 95% CI = 0.19 to 1.22, and comprehension (the Token test: SMD = 0.58, 95% CI = 0.07 to 1.09 without heterogeneity (I2 = 0%. The SMD of AAT and BDAE comprehension subtests was 0.32 (95% CI = -0.08 to 0.72 with moderate heterogeneity (I2 = 32%,P = 0.22. The effect size did not change significantly even when any one trial was eliminated. None of the patients from the 7 included articles reported adverse effects from rTMS.Low-frequency rTMS with a 90% resting motor threshold that targets the triangular part of the right inferior frontal gyrus (IFG has a positive effect on language recovery in patients with aphasia following

  11. The effectiveness of concept mapping on development of critical thinking in nursing education: A systematic review and meta-analysis.

    Science.gov (United States)

    Yue, Meng; Zhang, Meng; Zhang, Chunmei; Jin, Changde

    2017-05-01

    As an essential skill in daily clinical nursing practice, critical thinking ability has been an important objective in nursing education. Concept mapping enables nursing students connect new information to existing knowledge and integrates interdisciplinary knowledge. However, there is a lack of evidence related to critical thinking ability and concept mapping in nursing education. The purpose of this systematic review and meta-analysis was to assess the effect of concept mapping in developing critical thinking in nursing education. This systematic review was reported in line with Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). A search was conducted in PubMed, Web of science, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health (CINAHL) and China National Knowledge Infrastructure (CNKI). Randomized controlled trials (RCT) comparing concept mapping and traditional teaching method were retrieved. Data were collected by two reviewers according to the data extraction tables. The methodological quality of included studies was assessed by other two reviewers. The results of meta-analysis were presented using mean difference (MD). Thirteen trials were summarized in the systematic review and eleven trials were included in the meta-analysis. The pooled effect size showed that, comparing with traditional methods, concept mapping could improve subjects' critical thinking ability measured by California Critical Thinking Disposition Inventory (CCTDI), California Critical Thinking Skill Test (CCTST) and Critical Thinking Scale (CTS). The subgroup analyses showed that concept mapping improved the score of all subscales. The result of this review indicated that concept mapping could affect the critical thinking affective dispositions and critical thinking cognitive skills. Further high quality research using uniform evaluation is required. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Cognitive-behavioral high parental involvement treatments for pediatric obsessive-compulsive disorder: A meta-analysis.

    Science.gov (United States)

    Iniesta-Sepúlveda, Marina; Rosa-Alcázar, Ana I; Sánchez-Meca, Julio; Parada-Navas, José L; Rosa-Alcázar, Ángel

    2017-06-01

    A meta-analysis on the efficacy of cognitive-behavior-family treatment (CBFT) on children and adolescents with obsessive-compulsive disorder (OCD) was accomplished. The purposes of the study were: (a) to estimate the effect magnitude of CBFT in ameliorating obsessive-compulsive symptoms and reducing family accommodation on pediatric OCD and (b) to identify potential moderator variables of the effect sizes. A literature search enabled us to identify 27 studies that fulfilled our selection criteria. The effect size index was the standardized pretest-postest mean change index. For obsessive-compulsive symptoms, the adjusted mean effect size for CBFT was clinically relevant and statistically significant in the posttest (d adj =1.464). For family accommodation the adjusted mean effect size was also positive and statistically significant, but in a lesser extent than for obsessive-compulsive symptoms (d adj =0.511). Publication bias was discarded as a threat against the validity of the meta-analytic results. Large heterogeneity among effect sizes was found. Better results were found when CBFT was individually applied than in group (d + =2.429 and 1.409, respectively). CBFT is effective to reduce obsessive-compulsive symptoms, but offers a limited effect for family accommodation. Additional modules must be included in CBFT to improve its effectiveness on family accommodation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effectiveness of Various Innovative Learning Methods in Health Science Classrooms: A Meta-Analysis

    Science.gov (United States)

    Kalaian, Sema A.; Kasim, Rafa M.

    2017-01-01

    This study reports the results of a meta-analysis of the available literature on the effectiveness of various forms of innovative small-group learning methods on student achievement in undergraduate college health science classrooms. The results of the analysis revealed that most of the primary studies supported the effectiveness of the…

  14. Effective Interventions in Overweight or Obese Young Children: Systematic Review and Meta-Analysis

    NARCIS (Netherlands)

    Hoek, van E.; Feskens, E.J.M.; Bouwman, L.I.; Janse, A.J.

    2014-01-01

    Abstract Background: Treatment programs for overweight and obese young children are of variable effectiveness, and the characteristics of effective programs are unknown. In this systematic review with meta-analysis, the effectiveness of treatment programs for these children is summarized. Methods:

  15. Meta-Analysis of Social Cognition in Mild Cognitive Impairment.

    Science.gov (United States)

    Bora, Emre; Yener, Görsev G

    2017-07-01

    Social cognitive abilities are impaired in Alzheimer disease and other dementias. Recent studies suggested that social cognitive abilities might be also impaired in mild cognitive impairment (MCI). Current meta-analysis aimed to summarize available evidence for deficits in theory of mind (ToM) and emotion recognition in MCI. In this meta-analysis of 17 studies, facial emotion recognition and ToM performances of 513 individuals with MCI and 693 healthy controls were compared. Mild cognitive impairment was associated with significant impairments falling in the medium effect sizes range in ToM ( d = 0.63) and facial emotion recognition ( d = 0.58). Among individual emotions, recognition of fear and sadness were particularly impaired. There were no significant between-group differences in recognition of disgust, happiness, and surprise. Social cognitive deficits were more severe in multidomain MCI. There is a need for longitudinal studies investigating the potential role of social cognitive impairment in predicting conversion to dementia.

  16. Bias Corrections for Standardized Effect Size Estimates Used with Single-Subject Experimental Designs

    Science.gov (United States)

    Ugille, Maaike; Moeyaert, Mariola; Beretvas, S. Natasha; Ferron, John M.; Van den Noortgate, Wim

    2014-01-01

    A multilevel meta-analysis can combine the results of several single-subject experimental design studies. However, the estimated effects are biased if the effect sizes are standardized and the number of measurement occasions is small. In this study, the authors investigated 4 approaches to correct for this bias. First, the standardized effect…

  17. ERCC2 polymorphisms and radiation-induced adverse effects on normal tissue: systematic review with meta-analysis and trial sequential analysis

    International Nuclear Information System (INIS)

    Song, Yu-Zhe; Duan, Mei-Na; Zhang, Yu-Yu; Shi, Wei-Yan; Xia, Cheng-Cheng; Dong, Li-Hua

    2015-01-01

    The relationship between ERCC2 polymorphisms and the risk of radiotoxicity remains inconclusive. The aim of our study is to systematically evaluate the association between ERCC2 polymorphisms and the risk of radiotoxicity. Publications were identified through a search of the PubMed and Web of Science databases up to August 15, 2015. The pooled odds ratios (ORs) with corresponding 95 % confidence intervals (CIs) were calculated to evaluate the association between ERCC2 polymorphisms and radiotoxicity. Trial sequential analysis (TSA) and power calculation were performed to evaluate the type 1 and type 2 errors. Eleven studies involving 2584 patients were ultimately included in this meta-analysis. Conventional meta-analysis identified a significant association between ERCC2 rs13181 polymorphism and radiotoxicity (OR = 0.71, 95 % CI: 0.55-0.93, P = 0.01), but this association failed to get the confirmation of TSA. The minor allele of rs13181 polymorphism may confer a protect effect against radiotoxicity. To confirm this correlation at the level of OR = 0.71, an overall information size of approximate 2800 patients were needed. The online version of this article (doi:10.1186/s13014-015-0558-6) contains supplementary material, which is available to authorized users

  18. Sex differences in visual-spatial working memory: A meta-analysis.

    Science.gov (United States)

    Voyer, Daniel; Voyer, Susan D; Saint-Aubin, Jean

    2017-04-01

    Visual-spatial working memory measures are widely used in clinical and experimental settings. Furthermore, it has been argued that the male advantage in spatial abilities can be explained by a sex difference in visual-spatial working memory. Therefore, sex differences in visual-spatial working memory have important implication for research, theory, and practice, but they have yet to be quantified. The present meta-analysis quantified the magnitude of sex differences in visual-spatial working memory and examined variables that might moderate them. The analysis used a set of 180 effect sizes from healthy males and females drawn from 98 samples ranging in mean age from 3 to 86 years. Multilevel meta-analysis was used on the overall data set to account for non-independent effect sizes. The data also were analyzed in separate task subgroups by means of multilevel and mixed-effects models. Results showed a small but significant male advantage (mean d = 0.155, 95 % confidence interval = 0.087-0.223). All the tasks produced a male advantage, except for memory for location, where a female advantage emerged. Age of the participants was a significant moderator, indicating that sex differences in visual-spatial working memory appeared first in the 13-17 years age group. Removing memory for location tasks from the sample affected the pattern of significant moderators. The present results indicate a male advantage in visual-spatial working memory, although age and specific task modulate the magnitude and direction of the effects. Implications for clinical applications, cognitive model building, and experimental research are discussed.

  19. Effects of tibolone on fibrinogen and antithrombin III: A systematic review and meta-analysis of controlled trials.

    Science.gov (United States)

    Bała, Małgorzata; Sahebkar, Amirhossein; Ursoniu, Sorin; Serban, Maria-Corina; Undas, Anetta; Mikhailidis, Dimitri P; Lip, Gregory Y H; Rysz, Jacek; Banach, Maciej

    2017-10-01

    Tibolone is a synthetic steroid with estrogenic, androgenic and progestogenic activity, but the evidence regarding its effects on fibrinogen and antithrombin III (ATIII) has not been conclusive. We assessed the impact of tibolone on fibrinogen and ATIII through a systematic review and meta-analysis of available randomized controlled trials (RCTs). The search included PUBMED, Web of Science, Scopus, and Google Scholar (up to January 31st, 2016) to identify controlled clinical studies investigating the effects of oral tibolone treatment on fibrinogen and ATIII. Overall, the impact of tibolone on plasma fibrinogen concentrations was reported in 10 trials comprising 11 treatment arms. Meta-analysis did not suggest a significant reduction of fibrinogen levels following treatment with tibolone (WMD: -5.38%, 95% CI: -11.92, +1.16, p=0.107). This result was robust in the sensitivity analysis and not influenced after omitting each of the included studies from meta-analysis. When the studies were categorized according to the duration of treatment, there was no effect in the subsets of trials lasting either analysis. There was no differential effect of tibolone on plasma ATIII concentrations in trials with either analysis, meta-regression did not suggest any significant association between the changes in plasma concentrations of fibrinogen (slope: +0.40; 95% CI: -0.39, +1.19; p=0.317) and ATIII (slope: -0.17; 95% CI: -0.54, +0.20; p=0.374) with duration of treatment. In conclusion, meta-analysis did not suggest a significant reduction of fibrinogen and ATIII levels following treatment with tibolone. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Ataxia Telangiectasia–Mutated Gene Polymorphisms and Acute Normal Tissue Injuries in Cancer Patients After Radiation Therapy: A Systematic Review and Meta-analysis

    International Nuclear Information System (INIS)

    Dong, Lihua; Cui, Jingkun; Tang, Fengjiao; Cong, Xiaofeng; Han, Fujun

    2015-01-01

    Purpose: Studies of the association between ataxia telangiectasia–mutated (ATM) gene polymorphisms and acute radiation injuries are often small in sample size, and the results are inconsistent. We conducted the first meta-analysis to provide a systematic review of published findings. Methods and Materials: Publications were identified by searching PubMed up to April 25, 2014. Primary meta-analysis was performed for all acute radiation injuries, and subgroup meta-analyses were based on clinical endpoint. The influence of sample size and radiation injury incidence on genetic effects was estimated in sensitivity analyses. Power calculations were also conducted. Results: The meta-analysis was conducted on the ATM polymorphism rs1801516, including 5 studies with 1588 participants. For all studies, the cut-off for differentiating cases from controls was grade 2 acute radiation injuries. The primary meta-analysis showed a significant association with overall acute radiation injuries (allelic model: odds ratio = 1.33, 95% confidence interval: 1.04-1.71). Subgroup analyses detected an association between the rs1801516 polymorphism and a significant increase in urinary and lower gastrointestinal injuries and an increase in skin injury that was not statistically significant. There was no between-study heterogeneity in any meta-analyses. In the sensitivity analyses, small studies did not show larger effects than large studies. In addition, studies with high incidence of acute radiation injuries showed larger effects than studies with low incidence. Power calculations revealed that the statistical power of the primary meta-analysis was borderline, whereas there was adequate power for the subgroup analysis of studies with high incidence of acute radiation injuries. Conclusions: Our meta-analysis showed a consistency of the results from the overall and subgroup analyses. We also showed that the genetic effect of the rs1801516 polymorphism on acute radiation injuries was

  1. Psychosocial Interventions for Depressive and Anxiety Symptoms in Individuals with Chronic Kidney Disease: Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Michaela C. Pascoe

    2017-06-01

    Full Text Available Purpose: Depressive and anxiety symptoms are common amongst individuals with chronic kidney disease and are known to affect quality of life adversely. Psychosocial interventions have been shown to decrease depressive and anxiety symptoms in various chronic diseases, but few studies have examined their efficacy in people with chronic kidney disease and no meta-analysis has been published. Thus, the aim of the present systematic review and meta-analysis was to evaluate the effects of psychosocial interventions on depressive and anxiety symptoms as well as quality of life in individuals diagnosed with chronic kidney disease and/or their carers.Methods: In this systematic review and meta-analysis, we included published randomized controlled trials comparing psychosocial interventions versus usual care for impacting depressive and anxiety symptoms and quality of life.Results: Eight studies were included in the systematic review and six of these were subjected to meta-analysis. Psychosocial interventions were associated with a medium effect size for reduction in depressive symptoms and a small effect size for improved quality of life in the in individuals with chronic-kidney-disease and their carers. Some evidence suggested a reduction in anxiety.Conclusion: Psychosocial interventions appear to reduce depressive symptoms and improve quality of life in patients with chronic-kidney-disease and their carers and to have some beneficial impact on anxiety. However, the small number of identified studies indicates a need for further research in this field.

  2. Systematic review and meta-analysis of educational interventions designed to improve medication administration skills and safety of registered nurses.

    Science.gov (United States)

    Härkänen, Marja; Voutilainen, Ari; Turunen, Elina; Vehviläinen-Julkunen, Katri

    2016-06-01

    The aim of this study is to evaluate the nature, quality and effectiveness of educational interventions designed to increase the medication administration skills and safety of registered nurses working in hospitals. A systematic review with meta-analysis. Intervention studies designed to increase the medication administration skills and safety of nurses, indexed in one or more databases (CINAHL, PubMed, Scopus, Cochrane, PsycInfo, or Medic), and published in peer-reviewed journals between January 2000 and April 2015. The nature of the interventions was evaluated by narrative analysis, the quality of studies was assessed using the Effective Public Health Practise Project Quality Assessment Tool and the effectiveness of the interventions was ascertained by calculating effect sizes and conducting a meta-analysis. A total of 755 studies were identified and 14 intervention studies were reviewed. Interventions differed by their nature, including traditional classroom training, simulation, e-learning, slide show presentations, interactive CD-ROM programme, and the use of posters and pamphlets. All interventions appeared to improve medication administration safety and skills based on original p-values. Only five studies reached strong (n=1) or moderate (n=4) quality ratings and one of them had to be omitted from the meta-analysis due unclear measures of dispersion. The meta-analysis favoured the interventions, the pooled effect size (Hedges' g) was large, 1.06. The most effective interventions were a blended learning programme including e-learning and a 60-min PowerPoint presentation. The least effective educational intervention, an interactive internet-based e-learning course, was reported in the study that achieved the only strong quality rating. It is challenging to recommend any specific intervention, because all educational interventions seem to have a positive effect, although the size of the effect greatly varies. In the future, studies sharing similar contents and

  3. The Effect of Whey Protein Supplementation on the Temporal Recovery of Muscle Function Following Resistance Training: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Robert W. Davies

    2018-02-01

    Full Text Available Whey protein (WP is a widely consumed nutritional supplement, known to enhance strength and muscle mass during resistance training (RT regimens. Muscle protein anabolism is acutely elevated following RT, which is further enhanced by WP. As a result, there is reason to suggest that WP supplementation may be an effective nutritional strategy for restoring the acute loss of contractile function that occurs following strenuous RT. This systematic review and meta-analysis provides a synthesis of the literature to date, investigating the effect of WP supplementation on the recovery of contractile function in young, healthy adults. Eight studies, containing 13 randomised control trials (RCTs were included in this review and meta-analysis, from which individual standardised effect sizes (ESs were calculated, and a temporal overall ES was determined using a random-effects model. Whilst only half of the individual studies reported beneficial effects for WP, the high-quality evidence taken from the 13 RCTs was meta-analysed, yielding overall positive small to medium effects for WP from < 24 to 96 h (ES range = 0.4 to 0.7, for the temporal restoration of contractile function compared to the control treatment. Whilst the effects for WP were shown to be consistent over time, these results are limited to 13 RCTs, principally supporting the requirement for further comprehensive research in this area.

  4. Data analysis with the DIANA meta-scheduling approach

    International Nuclear Information System (INIS)

    Anjum, A; McClatchey, R; Willers, I

    2008-01-01

    The concepts, design and evaluation of the Data Intensive and Network Aware (DIANA) meta-scheduling approach for solving the challenges of data analysis being faced by CERN experiments are discussed in this paper. Our results suggest that data analysis can be made robust by employing fault tolerant and decentralized meta-scheduling algorithms supported in our DIANA meta-scheduler. The DIANA meta-scheduler supports data intensive bulk scheduling, is network aware and follows a policy centric meta-scheduling. In this paper, we demonstrate that a decentralized and dynamic meta-scheduling approach is an effective strategy to cope with increasing numbers of users, jobs and datasets. We present 'quality of service' related statistics for physics analysis through the application of a policy centric fair-share scheduling model. The DIANA meta-schedulers create a peer-to-peer hierarchy of schedulers to accomplish resource management that changes with evolving loads and is dynamic and adapts to the volatile nature of the resources

  5. Exploring Regional Variation in Roost Selection by Bats: Evidence from a Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    François Fabianek

    Full Text Available Tree diameter, tree height and canopy closure have been described by previous meta-analyses as being important characteristics in roost selection by cavity-roosting bats. However, size and direction of effects for these characteristics varied greatly among studies, also referred to as heterogeneity. Potential sources of heterogeneity have not been investigated in previous meta-analyses, which are explored by correlating additional covariates (moderator variables. We tested whether effect sizes from 34 studies were consistent enough to reject the null hypothesis that trees selected by bats did not significantly differ in their characteristics from randomly selected trees. We also examined whether heterogeneity in tree diameter effect sizes was correlated to moderator variables such as sex, bat species, habitat type, elevation and mean summer temperature.We used Hedges' g standardized mean difference as the effect size for the most common characteristics that were encountered in the literature. We estimated heterogeneity indices, potential publication bias, and spatial autocorrelation of our meta-data. We relied upon meta-regression and multi-model inference approaches to evaluate the effects of moderator variables on heterogeneity in tree diameter effect sizes.Tree diameter, tree height, snag density, elevation, and canopy closure were significant characteristics of roost selection by cavity-roosting bats. Size and direction of effects varied greatly among studies with respect to distance to water, tree density, slope, and bark remaining on trunks. Inclusion of mean summer temperature and sex in meta-regressions further explained heterogeneity in tree diameter effect sizes.Regional differences in roost selection for tree diameter were related to mean summer temperature. Large diameter trees play a central role in roost selection by bats, especially in colder regions, where they are likely to provide a warm and stable microclimate for reproductive

  6. Adolescent Sexual Health Communication and Condom Use: A Meta-Analysis

    Science.gov (United States)

    Widman, Laura; Noar, Seth M.; Choukas-Bradley, Sophia; Francis, Diane

    2014-01-01

    Objective Condom use is critical for the health of sexually active adolescents, and yet many adolescents fail to use condoms consistently. One interpersonal factor that may be key to condom use is sexual communication between sexual partners; however, the association between communication and condom use has varied considerably in prior studies of youth. The purpose of this meta-analysis was to synthesize the growing body of research linking adolescents’ sexual communication to condom use, and to examine several moderators of this association. Methods A total of 41 independent effect sizes from 34 studies with 15,046 adolescent participants (Mage=16.8, age range=12–23) were meta-analyzed. Results Results revealed a weighted mean effect size of the sexual communication-condom use relationship of r = .24, which was statistically heterogeneous (Q=618.86, pcommunication topic and communication format were statistically significant moderators (pcommunication about condom use (r = .34) than communication about sexual history (r = .15) or general safer sex topics (r = .14). Effect sizes were also larger for communication behavior formats (r = .27) and self-efficacy formats (r = .28), than for fear/concern (r = .18), future intention (r = .15), or communication comfort (r = −.15) formats. Conclusions Results highlight the urgency of emphasizing communication skills, particularly about condom use, in HIV/STI prevention work for youth. Implications for the future study of sexual communication are discussed. PMID:25133828

  7. Effect of Probiotics on Depression: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Huang, Ruixue; Wang, Ke; Hu, Jianan

    2016-08-06

    It has been reported that gut probiotics play a major role in the bidirectional communication between the gut and the brain. Probiotics may be essential to people with depression, which remains a global health challenge, as depression is a metabolic brain disorder. However, the efficacy of probiotics for depression is controversial. This study aimed to systematically review the existing evidence on the effect of probiotics-based interventions on depression. Randomized, controlled trials, identified through screening multiple databases and grey literature, were included in the meta-analysis. The meta-analysis was performed using Review Manager 5.3 software using a fixed-effects model. The meta-analysis showed that probiotics significantly decreased the depression scale score (MD (depressive disorder) = -0.30, 95% CI (-0.51--0.09), p = 0.005) in the subjects. Probiotics had an effect on both the healthy population (MD = -0.25, 95% CI (-0.47--0.03), p = 0.03) and patients with major depressive disorder (MDD) (MD = -0.73, 95% CI (-1.37--0.09), p = 0.03). Probiotics had an effect on the population aged under 60 (MD = -0.43, 95% CI (-0.72--0.13), p = 0.005), while it had no effect on people aged over 65 (MD = -0.18, 95% CI (-0.47-0.11), p = 0.22). This is the first systematic review and meta-analysis with the goal of determining the effect of probiotics on depression. We found that probiotics were associated with a significant reduction in depression, underscoring the need for additional research on this potential preventive strategy for depression.

  8. Oxidative and Anti-Oxidative Stress Markers in Chronic Glaucoma: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Benoist d’Azy, Cédric; Pereira, Bruno; Chiambaretta, Frédéric

    2016-01-01

    Chronic glaucoma is a multifactorial disease among which oxidative stress may play a major pathophysiological role. We conducted a systematic review and meta-analysis to evaluate the levels of oxidative and antioxidative stress markers in chronic glaucoma compared with a control group. The PubMed, Cochrane Library, Embase and Science Direct databases were searched for studies reporting oxidative and antioxidative stress markers in chronic glaucoma and in healthy controls using the following keywords: “oxidative stress” or “oxidant stress” or “nitrative stress” or “oxidative damage” or “nitrative damage” or “antioxidative stress” or “antioxidant stress” or “antinitrative stress” and “glaucoma”. We stratified our meta-analysis on the type of biomarkers, the type of glaucoma, and the origin of the sample (serum or aqueous humor). We included 22 case-control studies with a total of 2913 patients: 1614 with glaucoma and 1319 healthy controls. We included 12 studies in the meta-analysis on oxidative stress markers and 19 on antioxidative stress markers. We demonstrated an overall increase in oxidative stress markers in glaucoma (effect size = 1.64; 95%CI 1.20–2.09), ranging from an effect size of 1.29 in serum (95%CI 0.84–1.74) to 2.62 in aqueous humor (95%CI 1.60–3.65). Despite a decrease in antioxidative stress marker in serum (effect size = –0.41; 95%CI –0.72 to –0.11), some increased in aqueous humor (superoxide dismutase, effect size = 3.53; 95%CI 1.20–5.85 and glutathione peroxidase, effect size = 6.60; 95%CI 3.88–9.31). The differences in the serum levels of oxidative stress markers between glaucoma patients and controls were significantly higher in primary open angle glaucoma vs primary angle closed glaucoma (effect size = 12.7; 95%CI 8.78–16.6, P stress increased in glaucoma, both in serum and aqueous humor. Malonyldialdehyde seemed the best biomarkers of oxidative stress in serum. The increase of some

  9. Meta-Analysis of Psychological Assessment as a Therapeutic Intervention

    Science.gov (United States)

    Poston, John M.; Hanson, William E.

    2010-01-01

    This study entails the use of meta-analytic techniques to calculate and analyze 18 independent and 52 nonindependent effect sizes across 17 published studies of psychological assessment as a therapeutic intervention. In this sample of studies, which involves 1,496 participants, a significant overall Cohen's d effect size of 0.423 (95% CI [0.321,…

  10. Effect of Resistance Training Frequency on Gains in Muscular Strength: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Grgic, Jozo; Schoenfeld, Brad J; Davies, Timothy B; Lazinica, Bruno; Krieger, James W; Pedisic, Zeljko

    2018-05-01

    Current recommendations on resistance training (RT) frequency for gains in muscular strength are based on extrapolations from limited evidence on the topic, and thus their practical applicability remains questionable. To elucidate this issue, we conducted a systematic review and meta-analysis of the studies that compared muscular strength outcomes with different RT frequencies. To carry out this review, English-language literature searches of the PubMed/MEDLINE, Scopus, and SPORTDiscus databases were conducted. The meta-analysis was performed using a random-effects model. The meta-analysis models were generated with RT frequencies classified as a categorical variable as either 1, 2, 3, or 4+ times/week, or, if there were insufficient data in subgroup analyses, the training frequencies were categorized as 1, 2, or 3 times/week. Subgroup analyses were performed for potential moderators, including (1) training volume; (2) exercise selection for the 1 repetition maximum (RM) test (for both multi-joint and single-joint exercises); (3) upper and lower body strength gains; (4) training to muscular failure (for studies involving and not involving training to muscular failure); (5) age (for both middle-aged/older adults and young adults); and (6) sex (for men and for women). The methodological quality of studies was appraised using the modified Downs and Black checklist. A total of 22 studies were found to meet the inclusion criteria. The average score on the Downs and Black checklist was 18 (range 13-22 points). Four studies were classified as being of good methodological quality, while the rest were classified as being of moderate methodological quality. Results of the meta-analysis showed a significant effect (p = 0.003) of RT frequency on muscular strength gains. Effect sizes increased in magnitude from 0.74, 0.82, 0.93, and 1.08 for training 1, 2, 3, and 4+ times per week, respectively. A subgroup analysis of volume-equated studies showed no significant effect (p

  11. Associations between interleukin-1 gene polymorphisms and sepsis risk: a meta-analysis

    Science.gov (United States)

    2014-01-01

    Background Previous epidemiological studies have presented conflicting evidence regarding associations between interleukin-1 (IL-1) polymorphisms and sepsis susceptibility. We have performed a meta-analysis to evaluate possible associations between IL-1 polymorphisms and sepsis risk. Methods Eligible literature was retrieved from PubMed, Embase and Web of Knowledge databases until Jun 15, 2013. The pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using random-effects model in the overall and subgroup analysis based on ethnicity, sepsis severity and quality score. Results Eighteen studies addressing five IL-1 polymorphisms were included in this meta-analysis. For IL-1A-889 (rs1800587) polymorphism, significant association was observed in overall comparison for allelic effect (OR = 1.47, 95% CI = 1.01-2.13, P = 0.04). There were no significant associations between either IL-1B-511 (rs16944) or IL-1B-31 (rs1143627) and sepsis susceptibility in overall or subgroup analyses. For IL-1B + 3594 (rs143634) polymorphism, genotype TT decreased sepsis risk in overall analysis (OR = 0.59, 95% CI = 0.36-0.97, P = 0.04), as well as in Caucasian (OR = 0.57, 95% CI = 0.34-0.95, P = 0.03) and sepsis (OR = 0.55, 95% CI = 0.31-0.97, P = 0.04) subgroup analysis. For IL-1RN VNTR polymorphism, significant association was observed in overall comparison for allelic effect (OR = 1.40, 95% CI = 1.01-1.95, P = 0.04). Furthermore, the effect sizes of IL-1RN VNTR on sepsis risk increased with disease severity (septic shock OR > severe sepsis OR > sepsis OR). Conclusions Our meta-analysis indicated that IL-1A-889, IL-1B + 3954 and IL-1RN VNTR might be associated with sepsis susceptibility. However, further studies with larger sample sizes and from homogenous populations would be necessary to validate these findings. PMID:24428862

  12. Longitudinal Meta-analysis

    NARCIS (Netherlands)

    Hox, J.J.; Maas, C.J.M.; Lensvelt-Mulders, G.J.L.M.

    2004-01-01

    The goal of meta-analysis is to integrate the research results of a number of studies on a specific topic. Characteristic for meta-analysis is that in general only the summary statistics of the studies are used and not the original data. When the published research results to be integrated

  13. Analysis and meta-analysis of single-case designs with a standardized mean difference statistic: a primer and applications.

    Science.gov (United States)

    Shadish, William R; Hedges, Larry V; Pustejovsky, James E

    2014-04-01

    This article presents a d-statistic for single-case designs that is in the same metric as the d-statistic used in between-subjects designs such as randomized experiments and offers some reasons why such a statistic would be useful in SCD research. The d has a formal statistical development, is accompanied by appropriate power analyses, and can be estimated using user-friendly SPSS macros. We discuss both advantages and disadvantages of d compared to other approaches such as previous d-statistics, overlap statistics, and multilevel modeling. It requires at least three cases for computation and assumes normally distributed outcomes and stationarity, assumptions that are discussed in some detail. We also show how to test these assumptions. The core of the article then demonstrates in depth how to compute d for one study, including estimation of the autocorrelation and the ratio of between case variance to total variance (between case plus within case variance), how to compute power using a macro, and how to use the d to conduct a meta-analysis of studies using single-case designs in the free program R, including syntax in an appendix. This syntax includes how to read data, compute fixed and random effect average effect sizes, prepare a forest plot and a cumulative meta-analysis, estimate various influence statistics to identify studies contributing to heterogeneity and effect size, and do various kinds of publication bias analyses. This d may prove useful for both the analysis and meta-analysis of data from SCDs. Copyright © 2013 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  14. Effect of Whey Supplementation on Circulating C-Reactive Protein: A Meta-Analysis of Randomized Controlled Trials

    Science.gov (United States)

    Zhou, Ling-Mei; Xu, Jia-Ying; Rao, Chun-Ping; Han, Shufen; Wan, Zhongxiao; Qin, Li-Qiang

    2015-01-01

    Whey supplementation is beneficial for human health, possibly by reducing the circulating C-reactive protein (CRP) level, a sensitive marker of inflammation. Thus, a meta-analysis of randomized controlled trials was conducted to evaluate their relationship. A systematic literature search was conducted in July, 2014, to identify eligible studies. Either a fixed-effects model or a random-effects model was used to calculate pooled effects. The meta-analysis results of nine trials showed a slight, but no significant, reduction of 0.42 mg/L (95% CI −0.96, 0.13) in CRP level with the supplementation of whey protein and its derivates. Relatively high heterogeneity across studies was observed. Subgroup analyses showed that whey significantly lowered CRP by 0.72 mg/L (95% CI −0.97, −0.47) among trials with a daily whey dose ≥20 g/day and by 0.67 mg/L (95% CI −1.21, −0.14) among trials with baseline CRP ≥3 mg/L. Meta-regression analysis revealed that the baseline CRP level was a potential effect modifier of whey supplementation in reducing CRP. In conclusion, our meta-analysis did not find sufficient evidence that whey and its derivates elicited a beneficial effect in reducing circulating CRP. However, they may significantly reduce CRP among participants with highly supplemental doses or increased baseline CRP levels. PMID:25671415

  15. The effects of aromatherapy on sleep improvement: a systematic literature review and meta-analysis.

    Science.gov (United States)

    Hwang, Eunhee; Shin, Sujin

    2015-02-01

    To evaluate the existing data on aromatherapy interventions for improvement of sleep quality. Systematic literature review and meta-analysis on the effects of aromatherapy. Study Sources: Electronic databases, including the Korea Education and Research Information Service (KERIS), Korean studies Information Service System (KISS), National Assembly Library, and eight academies within the Korean Society of Nursing Science, were searched to identify studies published between 2000 and August 2013. Randomized controlled and quasi-experimental trials that included aromatherapy for the improvement of sleep quality. Of the 245 publications identified, 13 studies met the inclusion and exclusion criteria, and 12 studies were used in the meta-analysis. Meta-analysis of the 12 studies using a random-effects model revealed that the use of aromatherapy was effective in improving sleep quality (95% confidence interval [CI], 0.540-1.745; Z=3.716). Subgroup analysis revealed that inhalation aromatherapy (95% CI, 0.792-1.541; Z=6.107) was more effective than massage therapy (95% CI, 0.128-2.166; Z=2.205) in unhealthy (95% CI, 0.248-1.100; Z=3.100) and healthy (95% CI, 0.393-5.104; Z=2.287) participants, respectively. Readily available aromatherapy treatments appear to be effective and promote sleep. Thus, it is essential to develop specific guidelines for the efficient use of aromatherapy.

  16. Meta analysis on clinical effectiveness of Chinese medicine physiotherapy combined with tropicamide eye drops for pseudomyopia

    Directory of Open Access Journals (Sweden)

    Dan Li

    2018-05-01

    Full Text Available AIM:To evaluate the curative effect of Chinese medicine physiotherapy combined with tropicamide eye drops to treat pseudomyopia in children and adolescent. METHODS: We collected randomized controlled trials from CNKI, CBM, Wanfang database, PubMed, EMBASE and Cochrane Library in 2000-2015, and the improved Jadad scale was used to evaluate the methodology of the literature, and the data was extracted. The Review Manager 5.3 statistical software was used for meta analysis. RESULTS: A total of 5 articles were included in the analysis, with a total sample size of 836 cases. The curative effect of experimental group on pseudomyopia was better than that of control group, and the differences are statistically significant(Z=6.39, PCONCLUSION: Compared with topiramine eye drops alone, combined with traditional Chinese medicine therapy for treating pseudomyopia in children and adolescent is more effective, and is safe and reliable.

  17. The effect of financial development on economic growth: a meta-analysis

    NARCIS (Netherlands)

    Bijlsma, Michiel; Kool, Clemens; Non, Marielle

    2017-01-01

    Empirical studies on the finance-growth relationship show a wide range of estimated effects. We perform a meta-analysis on in total 551 estimates from 68 empirical studies that take private credit to GDP as a measure for financial development and distinguish between linear and logarithmic

  18. The effect of financial development on economic growth: a meta-analysis

    NARCIS (Netherlands)

    Bijlsma, Michiel; Kool, Clemens; Non, Marielle

    2017-01-01

    Empirical studies on the nance-growth relationship show a wide range of estimated effects. We perform a meta-analysis on in total 551 estimates from 68 empirical studies that take private credit to GDP as a measure for financial development and distinguish between linear and logarithmic

  19. The Influence of Judgment Calls on Meta-Analytic Findings.

    Science.gov (United States)

    Tarrahi, Farid; Eisend, Martin

    2016-01-01

    Previous research has suggested that judgment calls (i.e., methodological choices made in the process of conducting a meta-analysis) have a strong influence on meta-analytic findings and question their robustness. However, prior research applies case study comparison or reanalysis of a few meta-analyses with a focus on a few selected judgment calls. These studies neglect the fact that different judgment calls are related to each other and simultaneously influence the outcomes of a meta-analysis, and that meta-analytic findings can vary due to non-judgment call differences between meta-analyses (e.g., variations of effects over time). The current study analyzes the influence of 13 judgment calls in 176 meta-analyses in marketing research by applying a multivariate, multilevel meta-meta-analysis. The analysis considers simultaneous influences from different judgment calls on meta-analytic effect sizes and controls for alternative explanations based on non-judgment call differences between meta-analyses. The findings suggest that judgment calls have only a minor influence on meta-analytic findings, whereas non-judgment call differences between meta-analyses are more likely to explain differences in meta-analytic findings. The findings support the robustness of meta-analytic results and conclusions.

  20. Effects of different lower-limb sensory stimulation strategies on postural regulation-A systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mei Teng Woo

    Full Text Available Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high- pooled effect sizes (Unbiased (Hedges' g standardized mean differences (SMD = 0.31-0.66 were observed with the addition of noise in a Stochastic Resonance Stimulation Strategy (SRSS, in three populations (i.e., healthy young adults, older adults, and individuals with lower-limb injuries, and under different task constraints (i.e., unipedal, bipedal, and eyes open. A Textured Material Stimulation Strategy (TMSS enhanced postural control in the most challenging condition-eyes-closed on a stable surface (SMD = 0.61, and in older adults (SMD = 0.30. The Wearable Garments Stimulation Strategy (WGSS showed no or adverse effects (SMD = -0.68-0.05 under all task constraints and in all populations, except in individuals with lower-limb injuries (SMD = 0.20. Results of our systematic review and meta-analysis revealed that future research could consider combining two or more stimulation strategies in intervention treatments for postural regulation and balance problems, depending on individual needs.

  1. Effects of different lower-limb sensory stimulation strategies on postural regulation-A systematic review and meta-analysis.

    Science.gov (United States)

    Woo, Mei Teng; Davids, Keith; Liukkonen, Jarmo; Orth, Dominic; Chow, Jia Yi; Jaakkola, Timo

    2017-01-01

    Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high- pooled effect sizes (Unbiased (Hedges' g) standardized mean differences (SMD) = 0.31-0.66) were observed with the addition of noise in a Stochastic Resonance Stimulation Strategy (SRSS), in three populations (i.e., healthy young adults, older adults, and individuals with lower-limb injuries), and under different task constraints (i.e., unipedal, bipedal, and eyes open). A Textured Material Stimulation Strategy (TMSS) enhanced postural control in the most challenging condition-eyes-closed on a stable surface (SMD = 0.61), and in older adults (SMD = 0.30). The Wearable Garments Stimulation Strategy (WGSS) showed no or adverse effects (SMD = -0.68-0.05) under all task constraints and in all populations, except in individuals with lower-limb injuries (SMD = 0.20). Results of our systematic review and meta-analysis revealed that future research could consider combining two or more stimulation strategies in intervention treatments for postural regulation and balance problems, depending on individual needs.

  2. The revelation effect: A meta-analytic test of hypotheses.

    Science.gov (United States)

    Aßfalg, André; Bernstein, Daniel M; Hockley, William

    2017-12-01

    Judgments can depend on the activity directly preceding them. An example is the revelation effect whereby participants are more likely to claim that a stimulus is familiar after a preceding task, such as solving an anagram, than without a preceding task. We test conflicting predictions of four revelation-effect hypotheses in a meta-analysis of 26 years of revelation-effect research. The hypotheses' predictions refer to three subject areas: (1) the basis of judgments that are subject to the revelation effect (recollection vs. familiarity vs. fluency), (2) the degree of similarity between the task and test item, and (3) the difficulty of the preceding task. We use a hierarchical multivariate meta-analysis to account for dependent effect sizes and variance in experimental procedures. We test the revelation-effect hypotheses with a model selection procedure, where each model corresponds to a prediction of a revelation-effect hypothesis. We further quantify the amount of evidence for one model compared to another with Bayes factors. The results of this analysis suggest that none of the extant revelation-effect hypotheses can fully account for the data. The general vagueness of revelation-effect hypotheses and the scarcity of data were the major limiting factors in our analyses, emphasizing the need for formalized theories and further research into the puzzling revelation effect.

  3. Academic performance of children born preterm: a meta-analysis and meta-regression.

    Science.gov (United States)

    Twilhaar, E Sabrina; de Kieviet, Jorrit F; Aarnoudse-Moens, Cornelieke Sh; van Elburg, Ruurd M; Oosterlaan, Jaap

    2017-08-28

    Advances in neonatal healthcare have resulted in decreased mortality after preterm birth but have not led to parallel decreases in morbidity. Academic performance provides insight in the outcomes and specific difficulties and needs of preterm children. To study academic performance in preterm children born in the antenatal steroids and surfactant era and possible moderating effects of perinatal and demographic factors. PubMed, Web of Science and PsycINFO were searched for peer-reviewed articles. Cohort studies with a full-term control group reporting standardised academic performance scores of preterm children (Academic test scores and special educational needs of preterm and full-term children were analysed using random effects meta-analysis. Random effects meta-regressions were performed to explore the predictive role of perinatal and demographic factors for between-study variance in effect sizes. The 17 eligible studies included 2390 preterm children and 1549 controls. Preterm children scored 0.71 SD below full-term peers on arithmetic (pacademic performance (p=0.006). Preterm children born in the antenatal steroids and surfactant era show considerable academic difficulties. Preterm children with bronchopulmonarydysplasia are at particular risk for poor academic outcome. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Clinical effect of azithromycin as an adjunct to non-surgical treatment of chronic periodontitis: a meta-analysis of randomized controlled clinical trials.

    Science.gov (United States)

    Zhang, Z; Zheng, Y; Bian, X

    2016-06-01

    The results of recent published studies focusing on the effect of azithromycin as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis are inconsistent. We conducted a meta-analysis of randomized controlled clinical trials to examine the effect of azithromycin combined with SRP on periodontal clinical parameters as compared to SRP alone. An electronic search was carried out on Pubmed, Embase and the Cochrane Central Register of Controlled Trials from their earliest records through December 28, 2014 to identify studies that met pre-stated inclusion criteria. Reference lists of retrieved articles were also reviewed. Data were extracted independently by two authors. Either a fixed- or random-effects model was used to calculate the overall effect sizes of azithromycin on probing depth, attachment level (AL) and bleeding on probing (BOP). Heterogeneity was evaluated using the Q test and I(2) statistic. Publication bias was evaluated by Begg's test and Egger's test. A total of 14 trials were included in the meta-analysis. Compared with SRP alone, locally delivered azithromycin plus SRP statistically significantly reduced probing depth by 0.99 mm (95% CI 0.42-1.57) and increased AL by 1.12 mm (95% CI 0.31-1.92). In addition, systemically administered azithromycin plus SRP statistically significantly reduced probing depth by 0.21 mm (95% CI 0.12-0.29), BOP by 4.50% (95% CI 1.45-7.56) and increased AL by 0.23 mm (95% CI 0.07-0.39). Sensitivity analysis yielded similar results. No evidence of publication bias was observed. The additional benefit of systemic azithromycin was shown at the initially deep probing depth sites, but not at shallow or moderate sites. The overall effect sizes of systemic azithromycin showed a tendency to decrease with time, and meta-regression analysis suggested a negative relation between the length of follow-up and net change in probing depth (r = -0.05, p = 0.02). This meta-analysis provides further

  5. The effects of life review on psycho-spiritual well-being among patients with life-threatening illness: a systematic review and meta-analysis.

    Science.gov (United States)

    Chen, Ying; Xiao, Huimin; Yang, Yanqing; Lan, Xiuyan

    2017-07-01

    The aim of this study was to examine the strength of evidence regarding the effects of life review on psycho-spiritual well-being among patients with life-threatening illness. Life-threatening illness not only causes physical symptoms but also psycho-spiritual burdens. Life review has been widely implemented to assist people coping with these burdens. However, the effectiveness of life review is not clear. To date, no systematic review or meta-analysis has been published on this topic. A systematic review with meta- analysis consistent with the recommendations of the Cochrane Collaboration was conducted. Database searches included MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, CINAHL, PsycINFO, CNKI and VIP et al. up to April 2015. We also searched the grey literature, reviewed reference lists from relevant articles and book chapters and contacted experts. Nine randomized controlled trials (RCTs) and two controlled clinical trials (CCTs) were eligible for this systematic review and meta-analysis. The risk of bias for those studies were rated as moderate (n = 11). The meta-analyses demonstrated significant standardized mean differences or mean differences in favour of life review compared with the control for depression, quality of life and self-esteem. The findings indicate that life review can decrease depressive symptoms, improve quality of life and enhance self-esteem among patients with life-threatening illnesses. Multi-centre studies with adequate sample size and rigorous designs are needed in future research. © 2016 John Wiley & Sons Ltd.

  6. A meta-analysis on the relationship between self-reported presence and anxiety in virtual reality exposure therapy for anxiety disorders.

    Science.gov (United States)

    Ling, Yun; Nefs, Harold T; Morina, Nexhmedin; Heynderickx, Ingrid; Brinkman, Willem-Paul

    2014-01-01

    In virtual reality exposure therapy (VRET) for anxiety disorders, sense of presence in the virtual environment is considered the principal mechanism that enables anxiety to be felt. Existing studies on the relation between sense of presence and level of anxiety, however, have yielded mixed results on the correlation between the two. In this meta-analysis, we reviewed publications on VRET for anxiety that included self-reported presence and anxiety. The comprehensive search of the literature identified 33 publications with a total of 1196 participants. The correlation between self-reported sense of presence and anxiety was extracted and meta-analyzed. Potential moderators such as technology characteristics, sample characteristics including age, gender and clinical status, disorder characteristics and study design characteristics such as measurements were also examined. The random effects analysis showed a medium effect size for the correlation between sense of presence and anxiety (r = .28; 95% CI: 0.18-0.38). Moderation analyses revealed that the effect size of the correlation differed across different anxiety disorders, with a large effect size for fear of animals (r = .50; 95% CI: 0.30-0.66) and a no to small effect size for social anxiety disorder (r = .001; 95% CI: -0.19-0.19). Further, the correlation between anxiety and presence was stronger in studies with participants who met criteria for an anxiety disorder than in studies with a non-clinical population. Trackers with six degrees of freedom and displays with a larger field of view resulted in higher effect sizes, compared to trackers with three degrees of freedom and displays with a smaller field of view. In addition, no difference in effect size was found for the type of presence measurement and the type of anxiety measurement. This meta-analysis confirms the positive relation between sense of presence and anxiety and demonstrates that this relation can be affected by various moderating factors.

  7. Interventions to Improve Medication Adherence among Older Adults: Meta-Analysis of Adherence Outcomes among Randomized Controlled Trials

    Science.gov (United States)

    Conn, Vicki S.; Hafdahl, Adam R.; Cooper, Pamela S.; Ruppar, Todd M.; Mehr, David R.; Russell, Cynthia L.

    2009-01-01

    Purpose: This study investigated the effectiveness of interventions to improve medication adherence (MA) in older adults. Design and Methods: Meta-analysis was used to synthesize results of 33 published and unpublished randomized controlled trials. Random-effects models were used to estimate overall mean effect sizes (ESs) for MA, knowledge,…

  8. Evaluation of the association between acne and smoking: systematic review and meta-analysis of cross-sectional studies

    Directory of Open Access Journals (Sweden)

    Alice Mannocci

    2010-09-01

    Full Text Available MetaPlusBook-Roman; font-size: x-small;">

    Background: Acne vulgaris is one of the most common skin diseases with a multifactorial pathogenesis. Examination of the literature regarding the contribution of smoking to acne shows contradictory results. The aim of this study was to undertake a systematic review of the literature and meta-analysis about the association between acne and smoking.

    Methods: A systematic review and meta-analysis, when possible were performed. The literature review was based on Pubmed, Scopus and Google Scholar searches using the keywords “(smoking OR tobacco OR nicotine OR cigarettes AND acne”. Only cross-sectional studies were included. Meta-analyses were performed using the RevMan software version 5 for Windows. Four different meta-analyses were carried out: one evaluating the association between smoking habit and acne, one including data stratified by gender, one for studies with a quality score > 6, and one relating to acne classification.

    Results: Six studies were selected. The first meta-analysis, including all studies, showed a non significant role of smoke in the development of acne: OR 1.05 (95% CI: 0.66–1.67 with random effect estimate. The second meta-analyses, including data stratified by gender, showed a OR=0.99 (95% CI: 0.57–1.73 for males and a OR of 1.45 (95% CI: 0.08–24.64 for females, using random effect for the heterogeneity in both cases. The third meta-analysis, included studies with a quality score >6 resulted in an estimated OR= 0.69 (95% CI: 0.55–0.85: in this case it was possible to use the fixed effect estimate. The last meta-analysis, concerning the severity grading, showed a non-significant result: OR=1.09 (95% CI: 0.61–1.95 using the random effect approach.

    Conclusions: The first two meta-analyses found no signification association between smoking and

  9. Disclosure of sensitive behaviors across self-administered survey modes: a meta-analysis.

    Science.gov (United States)

    Gnambs, Timo; Kaspar, Kai

    2015-12-01

    In surveys, individuals tend to misreport behaviors that are in contrast to prevalent social norms or regulations. Several design features of the survey procedure have been suggested to counteract this problem; particularly, computerized surveys are supposed to elicit more truthful responding. This assumption was tested in a meta-analysis of survey experiments reporting 460 effect sizes (total N =125,672). Self-reported prevalence rates of several sensitive behaviors for which motivated misreporting has been frequently observed were compared across self-administered paper-and-pencil versus computerized surveys. The results revealed that computerized surveys led to significantly more reporting of socially undesirable behaviors than comparable surveys administered on paper. This effect was strongest for highly sensitive behaviors and surveys administered individually to respondents. Moderator analyses did not identify interviewer effects or benefits of audio-enhanced computer surveys. The meta-analysis highlighted the advantages of computerized survey modes for the assessment of sensitive topics.

  10. Meta-analysis of the antecedent and consequent constructs of materialism

    OpenAIRE

    Fernando de Oliveira Santini; Wagner Júnior Ladeira; Cláudio Hoffmann Sampaio; Clécio Falcão Araújo

    2017-01-01

    Purpose – Materialism has been gaining ground in the academic field, especially from the 1980s on, given the relevance of understanding sentiments connected to possessing and acquiring goods. Thus, this meta-analysis was carried out to assess the antecedents and consequents of materialism. Design/methodology/approach – Based on a systematic review, we gathered a total 77 articles that examined those aspects, generating 99 effects-sizes and a cumulative sample of 40,288 studied individuals...

  11. The Effects of Ability Grouping: A Meta-Analysis of Research Findings.

    Science.gov (United States)

    Noland, Theresa Koontz; Taylor, Bob L.

    The study reported in this paper quantitatively integrated the recent research findings on ability grouping in order to generalize about these effects on student achievement and student self-concept. Meta-analysis was used to statistically integrate the empirical data. The relationships among various experimental variables including grade level,…

  12. Ethnic density effects for adult mental health: systematic review and meta-analysis of international studies.

    Science.gov (United States)

    Bécares, Laia; Dewey, Michael E; Das-Munshi, Jayati

    2017-12-14

    Despite increased ethnic diversity in more economically developed countries it is unclear whether residential concentration of ethnic minority people (ethnic density) is detrimental or protective for mental health. This is the first systematic review and meta-analysis covering the international literature, assessing ethnic density associations with mental health outcomes. We systematically searched Medline, PsychINFO, Sociological Abstracts, Web of Science from inception to 31 March 2016. We obtained additional data from study authors. We conducted random-effects meta-analysis taking into account clustering of estimates within datasets. Meta-regression assessed heterogeneity in studies due to ethnicity, country, generation, and area-level deprivation. Our main exposure was ethnic density, defined as the residential concentration of own racial/ethnic minority group. Outcomes included depression, anxiety and the common mental disorders (CMD), suicide, suicidality, psychotic experiences, and psychosis. We included 41 studies in the review, with meta-analysis of 12 studies. In the meta-analyses, we found a large reduction in relative odds of psychotic experiences [odds ratio (OR) 0.82 (95% confidence interval (CI) 0.76-0.89)] and suicidal ideation [OR 0.88 (95% CI 0.79-0.98)] for each 10 percentage-point increase in own ethnic density. For CMD, depression, and anxiety, associations were indicative of protective effects of own ethnic density; however, results were not statistically significant. Findings from narrative review were consistent with those of the meta-analysis. The findings support consistent protective ethnic density associations across countries and racial/ethnic minority populations as well as mental health outcomes. This may suggest the importance of the social environment in patterning detrimental mental health outcomes in marginalized and excluded population groups.

  13. Arthritis self-management education programs: a meta-analysis of the effect on pain and disability.

    Science.gov (United States)

    Warsi, Asra; LaValley, Michael P; Wang, Philip S; Avorn, Jerry; Solomon, Daniel H

    2003-08-01

    Some reports suggest that education programs help arthritis patients better manage their symptoms and improve function. This review of the published literature was undertaken to assess the effect of such programs on pain and disability. Medline and HealthSTAR were searched for the period 1964-1998. The references of each article were then hand-searched for further publications. Studies were included in the meta-analysis if the intervention contained a self-management education component, a concurrent control group was included, and pain and/or disability were assessed as end points. Two authors reviewed each study. The methodologic attributes and efficacy of the interventions were assessed using a standardized abstraction tool, and the magnitude of the results was converted to a common measure, the effect size. Summary effect sizes were calculated separately for pain and disability. The search strategy yielded 35 studies, of which 17 met inclusion criteria. The mean age of study participants was 61 years, and 69% were female. On average, 19% of patients did not complete followup (range 0-53%). The summary effect size was 0.12 for pain (95% confidence interval [95% CI] 0.00, 0.24) and 0.07 for disability (95% CI 0.00, 0.15). Funnel plots indicated no significant evidence of bias toward the publication of studies with findings that showed reductions in pain or disability. The summary effect sizes suggest that arthritis self-management education programs result in small reductions in pain and disability.

  14. Musicians have better memory than nonmusicians: A meta-analysis

    Science.gov (United States)

    Altoè, Gianmarco; Carretti, Barbara; Grassi, Massimo

    2017-01-01

    Background Several studies have found that musicians perform better than nonmusicians in memory tasks, but this is not always the case, and the strength of this apparent advantage is unknown. Here, we conducted a meta-analysis with the aim of clarifying whether musicians perform better than nonmusicians in memory tasks. Methods Education Source; PEP (WEB)—Psychoanalytic Electronic Publishing; Psychology and Behavioral Science (EBSCO); PsycINFO (Ovid); PubMed; ScienceDirect—AllBooks Content (Elsevier API); SCOPUS (Elsevier API); SocINDEX with Full Text (EBSCO) and Google Scholar were searched for eligible studies. The selected studies involved two groups of participants: young adult musicians and nonmusicians. All the studies included memory tasks (loading long-term, short-term or working memory) that contained tonal, verbal or visuospatial stimuli. Three meta-analyses were run separately for long-term memory, short-term memory and working memory. Results We collected 29 studies, including 53 memory tasks. The results showed that musicians performed better than nonmusicians in terms of long-term memory, g = .29, 95% CI (.08–.51), short-term memory, g = .57, 95% CI (.41–.73), and working memory, g = .56, 95% CI (.33–.80). To further explore the data, we included a moderator (the type of stimulus presented, i.e., tonal, verbal or visuospatial), which was found to influence the effect size for short-term and working memory, but not for long-term memory. In terms of short-term and working memory, the musicians’ advantage was large with tonal stimuli, moderate with verbal stimuli, and small or null with visuospatial stimuli. Conclusions The three meta-analyses revealed a small effect size for long-term memory, and a medium effect size for short-term and working memory, suggesting that musicians perform better than nonmusicians in memory tasks. Moreover, the effect of the moderator suggested that, the type of stimuli influences this advantage. PMID:29049416

  15. The effectiveness of multi-component goal setting interventions for changing physical activity behaviour: a systematic review and meta-analysis.

    Science.gov (United States)

    McEwan, Desmond; Harden, Samantha M; Zumbo, Bruno D; Sylvester, Benjamin D; Kaulius, Megan; Ruissen, Geralyn R; Dowd, A Justine; Beauchamp, Mark R

    2016-01-01

    Drawing from goal setting theory (Latham & Locke, 1991; Locke & Latham, 2002; Locke et al., 1981), the purpose of this study was to conduct a systematic review and meta-analysis of multi-component goal setting interventions for changing physical activity (PA) behaviour. A literature search returned 41,038 potential articles. Included studies consisted of controlled experimental trials wherein participants in the intervention conditions set PA goals and their PA behaviour was compared to participants in a control group who did not set goals. A meta-analysis was ultimately carried out across 45 articles (comprising 52 interventions, 126 effect sizes, n = 5912) that met eligibility criteria using a random-effects model. Overall, a medium, positive effect (Cohen's d(SE) = .552(.06), 95% CI = .43-.67, Z = 9.03, p goal setting interventions in relation to PA behaviour was found. Moderator analyses across 20 variables revealed several noteworthy results with regard to features of the study, sample characteristics, PA goal content, and additional goal-related behaviour change techniques. In conclusion, multi-component goal setting interventions represent an effective method of fostering PA across a diverse range of populations and settings. Implications for effective goal setting interventions are discussed.

  16. Quantifying invertebrate resistance to floods: a global-scale meta-analysis.

    Science.gov (United States)

    McMullen, Laura E; Lytle, David A

    2012-12-01

    Floods are a key component of the ecology and management of riverine ecosystems around the globe, but it is not clear whether floods have predictable effects on organisms that can allow us to generalize across regions and continents. To address this, we conducted a global-scale meta-analysis to investigate effects of natural and managed floods on invertebrate resistance, the ability of invertebrates to survive flood events. We considered 994 studies for inclusion in the analysis, and after evaluation based on a priori criteria, narrowed our analysis to 41 studies spanning six of the seven continents. We used the natural-log-ratio of invertebrate abundance before and within 10 days after flood events because this measure of effect size can be directly converted to estimates of percent survival. We conducted categorical and continuous analyses that examined the contribution of environmental and study design variables to effect size heterogeneity, and examined differences in effect size among taxonomic groups. We found that invertebrate abundance was lowered by at least one-half after flood events. While natural vs. managed floods were similar in their effect, effect size differed among habitat and substrate types, with pools, sand, and boulders experiencing the strongest effect. Although sample sizes were not sufficient to examine all taxonomic groups, floods had a significant, negative effect on densities of Coleoptera, Eumalacostraca, Annelida, Ephemeroptera, Diptera, Plecoptera, and Trichoptera. Results from this study provide guidance for river flow regime prescriptions that will be applicable across continents and climate types, as well as baseline expectations for future empirical studies of freshwater disturbance.

  17. Cognitive-Based Interventions to Improve Mobility: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Marusic, Uros; Verghese, Joe; Mahoney, Jeannette R

    2018-06-01

    A strong relation between cognition and mobility has been identified in aging, supporting a role for enhancement mobility through cognitive-based interventions. However, a critical evaluation of the consistency of treatment effects of cognitive-based interventions is currently lacking. The objective of this study was 2-fold: (1) to review the existing literature on cognitive-based interventions aimed at improving mobility in older adults and (2) to assess the clinical effectiveness of cognitive interventions on gait performance. A systematic review of randomized controlled trials (RCT) of cognitive training interventions for improving simple (normal walking) and complex (dual task walking) gait was conducted in February 2018. Older adults without major cognitive, psychiatric, neurologic, and/or sensory impairments were included. Random effect meta-analyses and a subsequent meta-regression were performed to generate overall cognitive intervention effects on single- and dual-task walking conditions. Ten RCTs met inclusion criteria, with a total of 351 participants included in this meta-analysis. Cognitive training interventions revealed a small effect of intervention on complex gait [effect size (ES) = 0.47, 95% confidence interval (CI) 0.13 to 0.81, P = .007, I 2  = 15.85%], but not simple gait (ES = 0.35, 95% CI -0.01 to 0.71, P = .057, I 2  = 57.32%). Moreover, a meta-regression analysis revealed that intervention duration, training frequency, total number of sessions, and total minutes spent in intervention were not significant predictors of improvement in dual-task walking speed, though there was a suggestive trend toward a negative association between dual-task walking speed improvements and individual training session duration (P = .067). This meta-analysis provides support for the fact that cognitive training interventions can improve mobility-related outcomes, especially during challenging walking conditions requiring higher-order executive

  18. Low birth weight and intelligence in adolescence and early adulthood: a meta-analysis.

    Science.gov (United States)

    Kormos, C E; Wilkinson, A J; Davey, C J; Cunningham, A J

    2014-06-01

    Research has demonstrated an association between low birth weight (LBW; intelligence quotient (IQ) outcomes in childhood and early adolescence. We systematically evaluated whether this association persists into late adolescence and early adulthood and also assessed the influence of age of IQ assessment on effect size. During Stage 1 (meta-analysis of data on adolescents/adults), we searched for relevant articles in PsychINFO, PubMed, Ovid, CINAHL, ProQuest and ERIC until February 2011 (no lower limit). Studies which assessed full-scale IQ among LBW individuals (analysis provided a pooled estimate of the difference in IQ scores between LBW and NBW individuals. Publication bias was assessed using Rosenthal's classic fail-safe N and Duval and Tweedie's Trim and Fill. During Stage 2, we added data from the Kerr-Wilson et al. meta-analysis (which included data from children; in Meta-analysis of the association between preterm delivery and intelligence. Journal Public Health 2011;33:1-8) to our sample from Stage 1 and conducted a meta-regression to evaluate the effect of age of IQ assessment. Using a total of 15 studies in Stage 1, it was demonstrated that NBW individuals scored an average of 7.63 IQ points higher than LBW individuals, CI = 5.95-9.31. After adjusting for publication bias, NBW samples demonstrated an IQ of 4.98 points higher than LBW samples, CI = 3.20-6.77. Furthermore, age at IQ assessment was a significant moderator of the association between birth weight and IQ, in that the effect size decreased from childhood into young adulthood. Cognitive impairments associated with LBW persist into adolescence and early adulthood; however, the influence of LBW on IQ decreases from childhood to young adulthood. These conclusions must be interpreted with caution due to unmeasured variables and possible influence from publication bias. © The Author 2013. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions

  19. The Association of Unfavorable Traffic Events and Cannabis Usage: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Sorin Hostiuc

    2018-02-01

    Full Text Available Background: In the last years were published many epidemiological articles aiming to link driving under the influence of cannabis (DUIC with the risk of various unfavorable traffic events (UTEs, with sometimes contradictory results.Aim: The primary objective of this study was to analyze whether there is a significant association between DUIC and UTEs.Materials and Methods: We used two meta-analytical methods to assess the statistical significance of the effect size: random-effects model and inverse variance heterogeneity model.Results: Twenty-four studies were included in the meta-analysis. We obtained significant increases in the effect size for DUIC tested through blood analysis, with an odds ratio (OR of 2.27 and a confidence interval (CI between 1.36 and 3.80; death as an outcome, with an OR of 1.56 and a CI between 1.16 and 2.09; and case–control as the type of study, with an OR of 1.99 and a CI between 1.05 and 3.80. Publication bias was very high.Conclusion: Our analysis suggests that the overall effect size for DUIC on UTEs is not statistically significant, but there are significant differences obtained through subgroup analysis. This result might be caused by either methodological flaws (which are often encountered in articles on this topic, the indiscriminate employment of the term “cannabis use,” or an actual absence of an adverse effect. When a driver is found, in traffic, with a positive reaction suggesting cannabis use, the result should be corroborated by either objective data regarding marijuana usage (like blood analyses, with clear cut-off values, or a clinical assessment of the impairment, before establishing his/her fitness to drive.

  20. The Association of Unfavorable Traffic Events and Cannabis Usage: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Sorin Hostiuc

    2018-02-01

    Full Text Available Background: In the last years were published many epidemiological articles aiming to link driving under the influence of cannabis (DUIC with the risk of various unfavorable traffic events (UTEs, with sometimes contradictory results.Aim: The primary objective of this study was to analyze whether there is a significant association between DUIC and UTEs.Materials and Methods: We used two meta-analytical methods to assess the statistical significance of the effect size: random-effects model and inverse variance heterogeneity model.Results: Twenty-four studies were included in the meta-analysis. We obtained significant increases in the effect size for DUIC tested through blood analysis, with an odds ratio (OR of 1.97 and a confidence interval (CI between 1.35 and 2.87; death as an outcome, with an OR of 1.56 and a CI between 1.16 and 2.09; and case–control as the type of study, with an OR of 1.99 and a CI between 1.05 and 3.80. Publication bias was very high.Conclusion: Our analysis suggests that the overall effect size for DUIC on UTEs is not statistically significant, but there are significant differences obtained through subgroup analysis. This result might be caused by either methodological flaws (which are often encountered in articles on this topic, the indiscriminate employment of the term “cannabis use,” or an actual absence of an adverse effect. When a driver is found, in traffic, with a positive reaction suggesting cannabis use, the result should be corroborated by either objective data regarding marijuana usage (like blood analyses, with clear cut-off values, or a clinical assessment of the impairment, before establishing his/her fitness to drive.

  1. Effect and reporting bias of RhoA/ROCK-blockade intervention on locomotor recovery after spinal cord injury: a systematic review and meta-analysis.

    Science.gov (United States)

    Watzlawick, Ralf; Sena, Emily S; Dirnagl, Ulrich; Brommer, Benedikt; Kopp, Marcel A; Macleod, Malcolm R; Howells, David W; Schwab, Jan M

    2014-01-01

    Blockade of small GTPase-RhoA signaling pathway is considered a candidate translational strategy to improve functional outcome after spinal cord injury (SCI) in humans. Pooling preclinical evidence by orthodox meta-analysis is confounded by missing data (publication bias). To conduct a systematic review and meta-analysis of RhoA/Rho-associated coiled-coil containing protein kinase (ROCK) blocking approaches to (1) analyze the impact of bias that may lead to inflated effect sizes and (2) determine the normalized effect size of functional locomotor recovery after experimental thoracic SCI. We conducted a systematic search of PubMed, EMBASE, and Web of Science and hand searched related references. Studies were selected if they reported the effect of RhoA/ROCK inhibitors (C3-exoenzmye, fasudil, Y-27632, ibuprofen, siRhoA, and p21) in experimental spinal cord hemisection, contusion, or transection on locomotor recovery measured by the Basso, Beattie, and Bresnahan score or the Basso Mouse Scale for Locomotion. Two investigators independently assessed the identified studies. Details of individual study characteristics from each publication were extracted and effect sizes pooled using a random effects model. We assessed risk for bias using a 9-point-item quality checklist and calculated publication bias with Egger regression and the trim and fill method. A stratified meta-analysis was used to assess the impact of study characteristics on locomotor recovery. Thirty studies (725 animals) were identified. RhoA/ROCK inhibition was found to improve locomotor outcome by 21% (95% CI, 16.0-26.6). Assessment of publication bias by the trim and fill method suggested that 30% of experiments remain unpublished. Inclusion of these theoretical missing studies suggested a 27% overestimation of efficacy, reducing the overall efficacy to a 15% improvement in locomotor recovery. Low study quality was associated with larger estimates of neurobehavioral outcome. Taking into account

  2. Short-term Effect of Fine Particulate Matter on Children?s Hospital Admissions and Emergency Department Visits for Asthma: A Systematic Review and Meta-analysis

    OpenAIRE

    Lim, Hyungryul; Kwon, Ho-Jang; Lim, Ji-Ae; Choi, Jong Hyuk; Ha, Mina; Hwang, Seung-Sik; Choi, Won-Jun

    2016-01-01

    Objectives: No children-specified review and meta-analysis paper about the short-term effect of fine particulate matter (PM2.5) on hospital admissions and emergency department visits for asthma has been published. We calculated more precise pooled effect estimates on this topic and evaluated the variation in effect size according to the differences in study characteristics not considered in previous studies. Methods: Two authors each independently searched PubMed and EMBASE for relevant studi...

  3. Relapse rates after psychotherapy for depression - stable long-term effects? A meta-analysis.

    Science.gov (United States)

    Steinert, Christiane; Hofmann, Mareike; Kruse, Johannes; Leichsenring, Falk

    2014-10-01

    Depression is the most common mental disorder. Effective psychotherapeutic treatments for depression exist; however, data on their long-term effectiveness beyond a time span of two years is still scarce. Our aim was to perform a meta-analysis, investigating (a) overall rates of relapse more than two years after psychotherapy (meta-analysis 1), and (b) if psychotherapy has more enduring effects than non-psychotherapeutic comparison conditions (e.g. pharmacotherapy, treatment as usual), again beyond a time span of two years post-therapy (meta-analysis 2). We searched electronic databases Medline, PsycINFO and the COCHRANE Library. Main selection criteria were (i) RCT of psychotherapy with follow-up interval of more than 2 years, (ii) primary diagnosis of depression, assessed by observer ratings, (iii) report of relapse at follow-up. We identified 11 studies, 6 of which included a non-psychotherapeutic comparison condition. Together they comprised long-term data of 966 patients. Mean follow-up duration was 4.4 years. The overall relapse rate at long-term follow-up was 0.39 (95% CI 0.29, 0.50). Psychotherapy resulted in significantly less relapses (53.1% vs. 71.1%, OR 0.51; 95% CI 0.32, 0.82, p=0.005) than comparison treatments. This finding corresponded to a number needed to treat (NNT) of 5.55. Results can only be preliminary as data was sparse and studies differed methodologically. Heterogeneity in the first meta-analysis was high (I(2)=82%). Results indicated publication bias. The relapse rate more than two years after psychotherapy is relatively high, but significantly lower compared to non-psychotherapeutic treatments. Multiannual follow-ups should routinely be included in future psychotherapy RCTs. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Effects of Repeated-Sprint Training in Hypoxia on Sea-Level Performance: A Meta-Analysis.

    Science.gov (United States)

    Brocherie, Franck; Girard, Olivier; Faiss, Raphaël; Millet, Grégoire P

    2017-08-01

    Repeated-sprint training in hypoxia (RSH) is a recent intervention regarding which numerous studies have reported effects on sea-level physical performance outcomes that are debated. No previous study has performed a meta-analysis of the effects of RSH. We systematically reviewed the literature and meta-analyzed the effects of RSH versus repeated-sprint training in normoxia (RSN) on key components of sea-level physical performance, i.e., best and mean (all sprint) performance during repeated-sprint exercise and aerobic capacity (i.e., maximal oxygen uptake [[Formula: see text

  5. Detecting and correcting for publication bias in meta-analysis - A truncated normal distribution approach.

    Science.gov (United States)

    Zhu, Qiaohao; Carriere, K C

    2016-01-01

    Publication bias can significantly limit the validity of meta-analysis when trying to draw conclusion about a research question from independent studies. Most research on detection and correction for publication bias in meta-analysis focus mainly on funnel plot-based methodologies or selection models. In this paper, we formulate publication bias as a truncated distribution problem, and propose new parametric solutions. We develop methodologies of estimating the underlying overall effect size and the severity of publication bias. We distinguish the two major situations, in which publication bias may be induced by: (1) small effect size or (2) large p-value. We consider both fixed and random effects models, and derive estimators for the overall mean and the truncation proportion. These estimators will be obtained using maximum likelihood estimation and method of moments under fixed- and random-effects models, respectively. We carried out extensive simulation studies to evaluate the performance of our methodology, and to compare with the non-parametric Trim and Fill method based on funnel plot. We find that our methods based on truncated normal distribution perform consistently well, both in detecting and correcting publication bias under various situations.

  6. Image Sharing Technologies and Reduction of Imaging Utilization: A Systematic Review and Meta-analysis

    Science.gov (United States)

    Vest, Joshua R.; Jung, Hye-Young; Ostrovsky, Aaron; Das, Lala Tanmoy; McGinty, Geraldine B.

    2016-01-01

    Introduction Image sharing technologies may reduce unneeded imaging by improving provider access to imaging information. A systematic review and meta-analysis were conducted to summarize the impact of image sharing technologies on patient imaging utilization. Methods Quantitative evaluations of the effects of PACS, regional image exchange networks, interoperable electronic heath records, tools for importing physical media, and health information exchange systems on utilization were identified through a systematic review of the published and gray English-language literature (2004–2014). Outcomes, standard effect sizes (ESs), settings, technology, populations, and risk of bias were abstracted from each study. The impact of image sharing technologies was summarized with random-effects meta-analysis and meta-regression models. Results A total of 17 articles were included in the review, with a total of 42 different studies. Image sharing technology was associated with a significant decrease in repeat imaging (pooled effect size [ES] = −0.17; 95% confidence interval [CI] = [−0.25, −0.09]; P utilization (pooled ES = 0.20; 95% CI = [0.07, 0.32]; P = .002). For all outcomes combined, image sharing technology was not associated with utilization. Most studies were at risk for bias. Conclusions Image sharing technology was associated with reductions in repeat and unnecessary imaging, in both the overall literature and the most-rigorous studies. Stronger evidence is needed to further explore the role of specific technologies and their potential impact on various modalities, patient populations, and settings. PMID:26614882

  7. The effectiveness and safety of antifibrinolytics in patients with acute intracranial haemorrhage: statistical analysis plan for an individual patient data meta-analysis.

    Science.gov (United States)

    Ker, Katharine; Prieto-Merino, David; Sprigg, Nikola; Mahmood, Abda; Bath, Philip; Kang Law, Zhe; Flaherty, Katie; Roberts, Ian

    2017-01-01

    Introduction : The Antifibrinolytic Trialists Collaboration aims to increase knowledge about the effectiveness and safety of antifibrinolytic treatment by conducting individual patient data (IPD) meta-analyses of randomised trials. This article presents the statistical analysis plan for an IPD meta-analysis of the effects of antifibrinolytics for acute intracranial haemorrhage. Methods : The protocol for the IPD meta-analysis has been registered with PROSPERO (CRD42016052155). We will conduct an individual patient data meta-analysis of randomised controlled trials with 1000 patients or more assessing the effects of antifibrinolytics in acute intracranial haemorrhage. We will assess the effect on two co-primary outcomes: 1) death in hospital at end of trial follow-up, and 2) death in hospital or dependency at end of trial follow-up. The co-primary outcomes will be limited to patients treated within three hours of injury or stroke onset. We will report treatment effects using odds ratios and 95% confidence intervals. We use logistic regression models to examine how the effect of antifibrinolytics vary by time to treatment, severity of intracranial bleeding, and age. We will also examine the effect of antifibrinolytics on secondary outcomes including death, dependency, vascular occlusive events, seizures, and neurological outcomes. Secondary outcomes will be assessed in all patients irrespective of time of treatment. All analyses will be conducted on an intention-to-treat basis. Conclusions : This IPD meta-analysis will examine important clinical questions about the effects of antifibrinolytic treatment in patients with intracranial haemorrhage that cannot be answered using aggregate data. With IPD we can examine how effects vary by time to treatment, bleeding severity, and age, to gain better understanding of the balance of benefit and harms on which to base recommendations for practice.

  8. HIV-Associated Cognitive Impairment in Perinatally Infected Children: A Meta-analysis.

    Science.gov (United States)

    Phillips, Nicole; Amos, Taryn; Kuo, Caroline; Hoare, Jacqueline; Ipser, Jonathan; Thomas, Kevin G F; Stein, Dan J

    2016-11-01

    Research shows, conclusively, that perinatal HIV infection has negative effects on cognitive functioning of children and adolescents. However, the extent of these cognitive impairments is unknown. Current literature does not document specific cognitive domains most affected in HIV-infected children and adolescents. To systematically review and meta-analyze the degree of cognitive impairment, and the specific cognitive domains affected, in children and adolescents with perinatally acquired HIV infection. We systematically searched 5 electronic bibliographic databases, namely: PubMed, PsychINFO, Academic Search Premier, Scopus, and WorldCat, by using a search protocol specifically designed for this study. Studies were selected on the basis of set a priori eligibility criteria. Titles, abstracts, and full texts were assessed by 2 independent reviewers. Data from included studies were extracted into Microsoft Excel by 2 independent reviewers. Twenty-two studies were identified for inclusion in the systematic review and of this, 6 studies were included in the meta-analysis. Results from the meta-analysis indicated that working memory and executive function were the domains most affected by the HIV virus. Only 27% of the included studies were suitable to enter into the meta-analysis. There was significant geographic bias in published studies, with only 32% (7/22) of included studies from sub-Saharan Africa. The evidence supports an association between HIV infection in children and adolescents and cognitive impairment in the domains of working memory, executive function and processing speed, with effect size estimates also providing some support for deficits in visual memory and visual-spatial ability. Copyright © 2016 by the American Academy of Pediatrics.

  9. Quantitative structure-activity relationship (QSAR) models for polycyclic aromatic hydrocarbons (PAHs) dissipation in rhizosphere based on molecular structure and effect size

    International Nuclear Information System (INIS)

    Ma Bin; Chen Huaihai; Xu Minmin; Hayat, Tahir; He Yan; Xu Jianming

    2010-01-01

    Rhizoremediation is a significant form of bioremediation for polycyclic aromatic hydrocarbons (PAHs). This study examined the role of molecular structure in determining the rhizosphere effect on PAHs dissipation. Effect size in meta-analysis was employed as activity dataset for building quantitative structure-activity relationship (QSAR) models and accumulative effect sizes of 16 PAHs were used for validation of these models. Based on the genetic algorithm combined with partial least square regression, models for comprehensive dataset, Poaceae dataset, and Fabaceae dataset were built. The results showed that information indices, calculated as information content of molecules based on the calculation of equivalence classes from the molecular graph, were the most important molecular structural indices for QSAR models of rhizosphere effect on PAHs dissipation. The QSAR model, based on the molecular structure indices and effect size, has potential to be used in studying and predicting the rhizosphere effect of PAHs dissipation. - Effect size based on meta-analysis was used for building PAHs dissipation quantitative structure-activity relationship (QSAR) models.

  10. Quantitative structure-activity relationship (QSAR) models for polycyclic aromatic hydrocarbons (PAHs) dissipation in rhizosphere based on molecular structure and effect size

    Energy Technology Data Exchange (ETDEWEB)

    Ma Bin; Chen Huaihai; Xu Minmin; Hayat, Tahir [Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, College of Environmental and Natural Resource Sciences, Zhejiang University, Hangzhou 310029 (China); He Yan, E-mail: yhe2006@zju.edu.c [Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, College of Environmental and Natural Resource Sciences, Zhejiang University, Hangzhou 310029 (China); Xu Jianming, E-mail: jmxu@zju.edu.c [Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, College of Environmental and Natural Resource Sciences, Zhejiang University, Hangzhou 310029 (China)

    2010-08-15

    Rhizoremediation is a significant form of bioremediation for polycyclic aromatic hydrocarbons (PAHs). This study examined the role of molecular structure in determining the rhizosphere effect on PAHs dissipation. Effect size in meta-analysis was employed as activity dataset for building quantitative structure-activity relationship (QSAR) models and accumulative effect sizes of 16 PAHs were used for validation of these models. Based on the genetic algorithm combined with partial least square regression, models for comprehensive dataset, Poaceae dataset, and Fabaceae dataset were built. The results showed that information indices, calculated as information content of molecules based on the calculation of equivalence classes from the molecular graph, were the most important molecular structural indices for QSAR models of rhizosphere effect on PAHs dissipation. The QSAR model, based on the molecular structure indices and effect size, has potential to be used in studying and predicting the rhizosphere effect of PAHs dissipation. - Effect size based on meta-analysis was used for building PAHs dissipation quantitative structure-activity relationship (QSAR) models.

  11. Meta-analysis of genome-wide association from genomic prediction models

    Science.gov (United States)

    A limitation of many genome-wide association studies (GWA) in animal breeding is that there are many loci with small effect sizes; thus, larger sample sizes (N) are required to guarantee suitable power of detection. To increase sample size, results from different GWA can be combined in a meta-analys...

  12. Exposure to fluoride in drinking water and hip fracture risk: a meta-analysis of observational studies.

    Science.gov (United States)

    Yin, Xin-Hai; Huang, Guang-Lei; Lin, Du-Ren; Wan, Cheng-Cheng; Wang, Ya-Dong; Song, Ju-Kun; Xu, Ping

    2015-01-01

    Many observational studies have shown that exposure to fluoride in drinking water is associated with hip fracture risk. However, the findings are varied or even contradictory. In this work, we performed a meta-analysis to assess the relationship between fluoride exposure and hip fracture risk. PubMed and EMBASE databases were searched to identify relevant observational studies from the time of inception until March 2014 without restrictions. Data from the included studies were extracted and analyzed by two authors. Summary relative risks (RRs) with corresponding 95% confidence intervals (CIs) were pooled using random- or fixed-effects models as appropriate. Sensitivity analyses and meta-regression were conducted to explore possible explanations for heterogeneity. Finally, publication bias was assessed. Fourteen observational studies involving thirteen cohort studies and one case-control study were included in the meta-analysis. Exposure to fluoride in drinking water does not significantly increase the incidence of hip fracture (RRs, 1.05; 95% CIs, 0.96-1.15). Sensitivity analyses based on adjustment for covariates, effect measure, country, sex, sample size, quality of Newcastle-Ottawa Scale scores, and follow-up period validated the strength of the results. Meta-regression showed that country, gender, quality of Newcastle-Ottawa Scale scores, adjustment for covariates and sample size were not sources of heterogeneity. Little evidence of publication bias was observed. The present meta-analysis suggests that chronic fluoride exposure from drinking water does not significantly increase the risk of hip fracture. Given the potential confounding factors and exposure misclassification, further large-scale, high-quality studies are needed to evaluate the association between exposure to fluoride in drinking water and hip fracture risk.

  13. Exposure to fluoride in drinking water and hip fracture risk: a meta-analysis of observational studies.

    Directory of Open Access Journals (Sweden)

    Xin-Hai Yin

    Full Text Available Many observational studies have shown that exposure to fluoride in drinking water is associated with hip fracture risk. However, the findings are varied or even contradictory. In this work, we performed a meta-analysis to assess the relationship between fluoride exposure and hip fracture risk.PubMed and EMBASE databases were searched to identify relevant observational studies from the time of inception until March 2014 without restrictions. Data from the included studies were extracted and analyzed by two authors. Summary relative risks (RRs with corresponding 95% confidence intervals (CIs were pooled using random- or fixed-effects models as appropriate. Sensitivity analyses and meta-regression were conducted to explore possible explanations for heterogeneity. Finally, publication bias was assessed.Fourteen observational studies involving thirteen cohort studies and one case-control study were included in the meta-analysis. Exposure to fluoride in drinking water does not significantly increase the incidence of hip fracture (RRs, 1.05; 95% CIs, 0.96-1.15. Sensitivity analyses based on adjustment for covariates, effect measure, country, sex, sample size, quality of Newcastle-Ottawa Scale scores, and follow-up period validated the strength of the results. Meta-regression showed that country, gender, quality of Newcastle-Ottawa Scale scores, adjustment for covariates and sample size were not sources of heterogeneity. Little evidence of publication bias was observed.The present meta-analysis suggests that chronic fluoride exposure from drinking water does not significantly increase the risk of hip fracture. Given the potential confounding factors and exposure misclassification, further large-scale, high-quality studies are needed to evaluate the association between exposure to fluoride in drinking water and hip fracture risk.

  14. Effect of Consanguinity on Low Birth Weight: A Meta-Analysis.

    Science.gov (United States)

    Poorolajal, Jalal; Ameri, Pegah; Soltanian, Alireza; Bahrami, Masoud

    2017-03-01

    Consanguinity (when couples share at least one common ancestor) is a public health issue with a variety of distributions and incidence rates worldwide. Several epidemiological studies have explored the association between consanguinity and low birth weight (LBW). However, the results are inconsistent. This meta-analysis aimed to explore the overall association between consanguineous marriage and LBW. We searched PubMed, Web of Science, Scopus, ScienceDirect, and reference lists of articles up to May 2015. We included cohort, case-control, and cross-sectional studies addressing the association between consanguinity and LBW. We assessed heterogeneity using Q-test and I2 statistic. We explored publication bias using the Egger's and Begg's tests and the funnel plot. We meta-analyzed the data and reported the overall odds ratio (OR) and mean difference with 95% confidence intervals (CI) using the random-effects model. We included 24 out of 3941 retrieved studies, with 44,131 participants. We indicated that LBW was associated significantly with first-cousin marriages (OR = 1.36; 95% CI: 1.03, 1.69) and non-significantly with second-cousin marriages (OR = 1.20; 95% CI: 0.49, 1.91). Furthermore, first-cousin marriages can reduce the birth weight of siblings of consanguineous couples 144 g more compared to non-consanguineous marriages. This meta-analysis measured the association between consanguinity and LBW. Based on the current evidence, consanguineous marriage can increase the risk for LBW. However, further evidence based on large cohort studies conducted in different settings is required to make a robust conclusion regarding the effect of consanguinity on LBW.

  15. Effects of foot reflexology on fatigue, sleep and pain: a systematic review and meta-analysis.

    Science.gov (United States)

    Lee, Jeongsoon; Han, Misook; Chung, Younghae; Kim, Jinsun; Choi, Jungsook

    2011-12-01

    The purpose of this study was to evaluate the effectiveness of foot reflexology on fatigue, sleep and pain. A systematic review and meta-analysis were conducted. Electronic database and manual searches were conducted on all published studies reporting the effects of foot reflexology on fatigue, sleep, and pain. Forty four studies were eligible including 15 studies associated with fatigue, 18 with sleep, and 11 with pain. The effects of foot reflexology were analyzed using Comprehensive Meta-Analysis Version 2.0. The homogeneity and the fail-safe N were calculated. Moreover, a funnel plot was used to assess publication bias. The effects on fatigue, sleep, and pain were not homogeneous and ranged from 0.63 to 5.29, 0.01 to 3.22, and 0.43 to 2.67, respectively. The weighted averages for fatigue, sleep, and pain were 1.43, 1.19, and 1.35, respectively. No publication bias was detected as evaluated by fail-safe N. Foot reflexology had a larger effect on fatigue and sleep and a smaller effect on pain. This meta-analysis indicates that foot reflexology is a useful nursing intervention to relieve fatigue and to promote sleep. Further studies are needed to evaluate the effects of foot reflexology on outcome variables other than fatigue, sleep and pain.

  16. An improved method for bivariate meta-analysis when within-study correlations are unknown.

    Science.gov (United States)

    Hong, Chuan; D Riley, Richard; Chen, Yong

    2018-03-01

    Multivariate meta-analysis, which jointly analyzes multiple and possibly correlated outcomes in a single analysis, is becoming increasingly popular in recent years. An attractive feature of the multivariate meta-analysis is its ability to account for the dependence between multiple estimates from the same study. However, standard inference procedures for multivariate meta-analysis require the knowledge of within-study correlations, which are usually unavailable. This limits standard inference approaches in practice. Riley et al proposed a working model and an overall synthesis correlation parameter to account for the marginal correlation between outcomes, where the only data needed are those required for a separate univariate random-effects meta-analysis. As within-study correlations are not required, the Riley method is applicable to a wide variety of evidence synthesis situations. However, the standard variance estimator of the Riley method is not entirely correct under many important settings. As a consequence, the coverage of a function of pooled estimates may not reach the nominal level even when the number of studies in the multivariate meta-analysis is large. In this paper, we improve the Riley method by proposing a robust variance estimator, which is asymptotically correct even when the model is misspecified (ie, when the likelihood function is incorrect). Simulation studies of a bivariate meta-analysis, in a variety of settings, show a function of pooled estimates has improved performance when using the proposed robust variance estimator. In terms of individual pooled estimates themselves, the standard variance estimator and robust variance estimator give similar results to the original method, with appropriate coverage. The proposed robust variance estimator performs well when the number of studies is relatively large. Therefore, we recommend the use of the robust method for meta-analyses with a relatively large number of studies (eg, m≥50). When the

  17. Meta-analysis of the Effectiveness of Educational and Therapeutic Interventions on the Four Classes of Learning Disorders

    Directory of Open Access Journals (Sweden)

    Javad Mesrabadi

    2018-04-01

    Full Text Available Abstract Background: Learning disorders is one of the most common problems of students, which attracted the attention of many psychologists and many studies have been conducted on the effectiveness of various interventions on different classes of learning disorder. The present study aimed to conclude general conclusions about the effectiveness of various educational and therapeutic interventions and the discovery of possible moderating variables. Materials and Methods: In order to achieve the research purpose by using meta-analysis method, quantitative results of 128 selected researches which were obtained according to the criteria for entering and leaving and using keywords were used. In total, 623 primary effect sizes were obtained and analyzed by using CMA2 software. Results: The results of the analysis showed that amount of combined effect size of the educational and therapeutic interventions on learning disorders was 1.13, and after dividing into multiple predecessor and consequence variables, the amounts of the combined effect size for educational interventions and therapeutic interventions for overall class of learning disabilities were respectively 0.74 and 1.26, for reading disorder 0.87 and 1.01, for writing disorder 1.20 and 1.22, and for mathematical disorder 1.29 and 1.26 that all of these effects size were significant (p≤0.001. Also, the results of independent t-test showed that the difference in the effectiveness of therapeutic interventions on reading disorder and educational interventions on mathematical disorder is significant (p≤0.001. Conclusion: Based on the size of the effects obtained, it can be said that educational and therapeutic interventions have a very high effect on learning disabilities, and the use of therapeutic interventions for reading disorder and educational interventions for mathematical disorder is more effective.

  18. Meta-analysis of the effects of forest fragmentation on interspecific interactions.

    Science.gov (United States)

    Magrach, Ainhoa; Laurance, William F; Larrinaga, Asier R; Santamaria, Luis

    2014-10-01

    Forest fragmentation dramatically alters species persistence and distribution and affects many ecological interactions among species. Recent studies suggest that mutualisms, such as pollination and seed dispersal, are more sensitive to the negative effects of forest fragmentation than antagonisms, such as predation or herbivory. We applied meta-analytical techniques to evaluate this hypothesis and quantified the relative contributions of different components of the fragmentation process (decreases in fragment size, edge effects, increased isolation, and habitat degradation) to the overall effect. The effects of fragmentation on mutualisms were primarily driven by habitat degradation, edge effects, and fragment isolation, and, as predicted, they were consistently more negative on mutualisms than on antagonisms. For the most studied interaction type, seed dispersal, only certain components of fragmentation had significant (edge effects) or marginally significant (fragment size) effects. Seed size modulated the effect of fragmentation: species with large seeds showed stronger negative impacts of fragmentation via reduced dispersal rates. Our results reveal that different components of the habitat fragmentation process have varying impacts on key mutualisms. We also conclude that antagonistic interactions have been understudied in fragmented landscapes, most of the research has concentrated on particular types of mutualistic interactions such as seed dispersal, and that available studies of interspecific interactions have a strong geographical bias (arising mostly from studies carried out in Brazil, Chile, and the United States). © 2014 Society for Conservation Biology.

  19. Psychotherapy for chronic major depression and dysthymia: A meta analysis.

    NARCIS (Netherlands)

    Cuijpers, P.; Straten, van A.; Schuurmans, J.; Oppen, van P.C.; Hollon, S.D.; Andersson, G.

    2009-01-01

    Abstract Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic

  20. Meta-analysis of the effect of road safety campaigns on accidents.

    Science.gov (United States)

    Phillips, Ross Owen; Ulleberg, Pål; Vaa, Truls

    2011-05-01

    A meta-analysis of 67 studies evaluating the effect of road safety campaigns on accidents is reported. A total of 119 results were extracted from the studies, which were reported in 12 different countries between 1975 and 2007. After allowing for publication bias and heterogeneity of effects, the weighted average effect of road safety campaigns is a 9% reduction in accidents (with 95% confidence that the weighted average is between -12 and -6%). To account for the variability of effects measured across studies, data were collected to characterise aspects of the campaign and evaluation design associated with each effect, and analysed to identify a model of seven campaign factors for testing by meta-regression. The model was tested using both fixed and random effect meta-regression, and dependency among effects was accounted for by aggregation. These analyses suggest positive associations between accident reduction and the use of personal communication or roadside media as part of a campaign delivery strategy. Campaigns with a drink-driving theme were also associated with greater accident reductions, while some of the analyses suggested that accompanying enforcement and short campaign duration (less than one month) are beneficial. Overall the results are consistent with the idea that campaigns can be more effective in the short term if the message is delivered with personal communication in a way that is proximal in space and time to the behaviour targeted by the campaign. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Veterinary homeopathy: meta-analysis of randomised placebo-controlled trials.

    Science.gov (United States)

    Mathie, Robert T; Clausen, Jürgen

    2015-01-01

    Meta-analysis of randomised controlled trials (RCTs) of veterinary homeopathy has not previously been undertaken. For all medical conditions and species collectively, we tested the hypothesis that the outcome of homeopathic intervention (treatment and/or prophylaxis, individualised and/or non-individualised) is distinguishable from corresponding intervention using placebos. All facets of the review, including literature search strategy, study eligibility, data extraction and assessment of risk of bias, were described in an earlier paper. A trial was judged to comprise reliable evidence if its risk of bias was low or was unclear in specific domains of assessment. Effect size was reported as odds ratio (OR). A trial was judged free of vested interest if it was not funded by a homeopathic pharmacy. Meta-analysis was conducted using the random-effects model, with hypothesis-driven sensitivity analysis based on risk of bias. Nine of 15 trials with extractable data displayed high risk of bias; low or unclear risk of bias was attributed to each of the remaining six trials, only two of which comprised reliable evidence without overt vested interest. For all N = 15 trials, pooled OR = 1.69 [95% confidence interval (CI), 1.12 to 2.56]; P = 0.01. For the N = 2 trials with suitably reliable evidence, pooled OR = 2.62 [95% CI, 1.13 to 6.05]; P = 0.02). Meta-analysis provides some very limited evidence that clinical intervention in animals using homeopathic medicines is distinguishable from corresponding intervention using placebos. The low number and quality of the trials hinders a more decisive conclusion. Copyright © 2014 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  2. Simulation-based training for nurses: Systematic review and meta-analysis.

    Science.gov (United States)

    Hegland, Pål A; Aarlie, Hege; Strømme, Hilde; Jamtvedt, Gro

    2017-07-01

    Simulation-based training is a widespread strategy to improve health-care quality. However, its effect on registered nurses has previously not been established in systematic reviews. The aim of this systematic review is to evaluate effect of simulation-based training on nurses' skills and knowledge. We searched CDSR, DARE, HTA, CENTRAL, CINAHL, MEDLINE, Embase, ERIC, and SveMed+ for randomised controlled trials (RCT) evaluating effect of simulation-based training among nurses. Searches were completed in December 2016. Two reviewers independently screened abstracts and full-text, extracted data, and assessed risk of bias. We compared simulation-based training to other learning strategies, high-fidelity simulation to other simulation strategies, and different organisation of simulation training. Data were analysed through meta-analysis and narrative syntheses. GRADE was used to assess the quality of evidence. Fifteen RCTs met the inclusion criteria. For the comparison of simulation-based training to other learning strategies on nurses' skills, six studies in the meta-analysis showed a significant, but small effect in favour of simulation (SMD -1.09, CI -1.72 to -0.47). There was large heterogeneity (I 2 85%). For the other comparisons, there was large between-study variation in results. The quality of evidence for all comparisons was graded as low. The effect of simulation-based training varies substantially between studies. Our meta-analysis showed a significant effect of simulation training compared to other learning strategies, but the quality of evidence was low indicating uncertainty. Other comparisons showed inconsistency in results. Based on our findings simulation training appears to be an effective strategy to improve nurses' skills, but further good-quality RCTs with adequate sample sizes are needed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Effects of music therapy on mood, language, behavior, and social skills in children with autism:A meta-analysis

    Institute of Scientific and Technical Information of China (English)

    Zhi-Min Shi; Gui-Hong Lin; Qing Xie

    2016-01-01

    Objective: To investigate the effects of music therapy on mood, language, behavior, and social skills in children with autism. Methods: A literature search was conducted using the following Chinese databases:the China National Knowledge Infrastructure (CNKI), Wanfang Data, the Chinese Biomedical Literature (CBM) Database, and the VIP Chinese Science and Technology Periodicals Database. The search terms were“autistic children”or“children with autism”and“music therapy”or“music treatment.”Studies of randomized controlled trials (RCTs) were included, and each publication included was assessed for quality. A meta-analysis was conducted using RevMan 5.1. Results: Publications were selected based on the inclusion and exclusion criteria. Six research articles describing RCTs were included; the total sample size was 300 patients. The results of meta-analysis showed that music therapy improved mood [Risk ratio (RR) ¼ 3.02, 95% confidence interval (CI) ¼ 1.93e4.11, Z ¼ 5.45, P Conclusions: Music therapy can improve mood, language, sensory perception, behavior, and social skills in children with autism.

  4. Lipid profile changes after pomegranate consumption: A systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Sahebkar, Amirhossein; Simental-Mendía, Luis E; Giorgini, Paolo; Ferri, Claudio; Grassi, Davide

    2016-10-15

    Transport of oxidized low-density lipoprotein across the endothelium into the artery wall is considered a fundamental priming step for the atherosclerotic process. Recent studies reported potential therapeutic effects of micronutrients found in natural products, indicating positive applications for controlling the pathogenesis of chronic cardiovascular disease driven by cardiovascular risk factors and oxidative stress. A particular attention has been recently addressed to pomegranate; however findings of clinical studies have been contrasting. To evaluate the effects of pomegranate consumption on plasma lipid concentrations through a systematic review and meta-analysis of randomized controlled trials (RCTs). The study was designed according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement. Scopus and Medline databases were searched to identify randomized placebo-controlled trials investigating the impact of pomegranate on plasma lipid concentrations. A fixed-effects model and the generic inverse variance method were used for quantitative data synthesis. Sensitivity analysis was conducted using the one-study remove approach. Random-effects meta-regression was performed to assess the impact of potential confounders on the estimated effect sizes. A total of 545 individuals were recruited from the 12 RCTs. Fixed-effect meta-analysis of data from 12 RCTs (13 treatment arms) did not show any significant effect of pomegranate consumption on plasma lipid concentrations. The results of meta-regression did not suggest any significant association between duration of supplementation and impact of pomegranate on total cholesterol and HDL-C, while an inverse association was found with changes in triglycerides levels (slope: -1.07; 95% CI: -2.03 to -0.11; p = 0.029). There was no association between the amount of pomegranate juice consumed per day and respective changes in plasma total cholesterol, LDL-C, HDL-C and triglycerides. The

  5. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults

    Science.gov (United States)

    Morton, Robert W; Murphy, Kevin T; McKellar, Sean R; Schoenfeld, Brad J; Henselmans, Menno; Helms, Eric; Aragon, Alan A; Devries, Michaela C; Banfield, Laura; Krieger, James W

    2018-01-01

    Objective We performed a systematic review, meta-analysis and meta-regression to determine if dietary protein supplementation augments resistance exercise training (RET)-induced gains in muscle mass and strength. Data sources A systematic search of Medline, Embase, CINAHL and SportDiscus. Eligibility criteria Only randomised controlled trials with RET ≥6 weeks in duration and dietary protein supplementation. Design Random-effects meta-analyses and meta-regressions with four a priori determined covariates. Two-phase break point analysis was used to determine the relationship between total protein intake and changes in fat-free mass (FFM). Results Data from 49 studies with 1863 participants showed that dietary protein supplementation significantly (all pFFM (0.30 kg (0.09, 0.52)) and muscle size—muscle fibre cross-sectional area (CSA; 310 µm2 (51, 570)) and mid-femur CSA (7.2 mm2 (0.20, 14.30)) during periods of prolonged RET. The impact of protein supplementation on gains in FFM was reduced with increasing age (−0.01 kg (−0.02,–0.00), p=0.002) and was more effective in resistance-trained individuals (0.75 kg (0.09, 1.40), p=0.03). Protein supplementation beyond total protein intakes of 1.62 g/kg/day resulted in no further RET-induced gains in FFM. Summary/conclusion Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults. Increasing age reduces and training experience increases the efficacy of protein supplementation during RET. With protein supplementation, protein intakes at amounts greater than ~1.6 g/kg/day do not further contribute RET-induced gains in FFM. PMID:28698222

  6. Inference for binomial probability based on dependent Bernoulli random variables with applications to meta-analysis and group level studies.

    Science.gov (United States)

    Bakbergenuly, Ilyas; Kulinskaya, Elena; Morgenthaler, Stephan

    2016-07-01

    We study bias arising as a result of nonlinear transformations of random variables in random or mixed effects models and its effect on inference in group-level studies or in meta-analysis. The findings are illustrated on the example of overdispersed binomial distributions, where we demonstrate considerable biases arising from standard log-odds and arcsine transformations of the estimated probability p̂, both for single-group studies and in combining results from several groups or studies in meta-analysis. Our simulations confirm that these biases are linear in ρ, for small values of ρ, the intracluster correlation coefficient. These biases do not depend on the sample sizes or the number of studies K in a meta-analysis and result in abysmal coverage of the combined effect for large K. We also propose bias-correction for the arcsine transformation. Our simulations demonstrate that this bias-correction works well for small values of the intraclass correlation. The methods are applied to two examples of meta-analyses of prevalence. © 2016 The Authors. Biometrical Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  7. Meta-analysis of Big Five personality traits in autism spectrum disorder.

    Science.gov (United States)

    Lodi-Smith, Jennifer; Rodgers, Jonathan D; Cunningham, Sara A; Lopata, Christopher; Thomeer, Marcus L

    2018-04-01

    The present meta-analysis synthesizes the emerging literature on the relationship of Big Five personality traits to autism spectrum disorder. Studies were included if they (1) either (a) measured autism spectrum disorder characteristics using a metric that yielded a single score quantification of the magnitude of autism spectrum disorder characteristics and/or (b) studied individuals with an autism spectrum disorder diagnosis compared to individuals without an autism spectrum disorder diagnosis and (2) measured Big Five traits in the same sample or samples. Fourteen reviewed studies include both correlational analyses and group comparisons. Eighteen effect sizes per Big Five trait were used to calculate two overall effect sizes per trait. Meta-analytic effects were calculated using random effects models. Twelve effects (per trait) from nine studies reporting correlations yielded a negative association between each Big Five personality trait and autism spectrum disorder characteristics (Fisher's z ranged from -.21 (conscientiousness) to -.50 (extraversion)). Six group contrasts (per trait) from six studies comparing individuals diagnosed with autism spectrum disorder to neurotypical individuals were also substantial (Hedges' g ranged from -.88 (conscientiousness) to -1.42 (extraversion)). The potential impact of personality on important life outcomes and new directions for future research on personality in autism spectrum disorder are discussed in light of results.

  8. The Effects of Music on Pain: A Meta-Analysis.

    Science.gov (United States)

    Lee, Jin Hyung

    2016-01-01

    Numerous meta-analyses have been conducted on the topic of music and pain, with the latest comprehensive study published in 2006. Since that time, more than 70 randomized controlled trials (RCTs) have been published, necessitating a new and comprehensive review. The aim of this meta-analysis was to examine published RCT studies investigating the effect of music on pain. The present study included RCTs published between 1995 and 2014. Studies were obtained by searching 12 databases and hand-searching related journals and reference lists. Main outcomes were pain intensity, emotional distress from pain, vital signs, and amount of analgesic intake. Study quality was evaluated according to the Cochrane Collaboration guidelines. Analysis of the 97 included studies revealed that music interventions had statistically significant effects in decreasing pain on 0-10 pain scales (MD = -1.13), other pain scales (SMD = -0.39), emotional distress from pain (MD = -10.83), anesthetic use (SMD = -0.56), opioid intake (SMD = -0.24), non-opioid intake (SMD = -0.54), heart rate (MD = -4.25), systolic blood pressure (MD = -3.34), diastolic blood pressure (MD = -1.18), and respiration rate (MD = -1.46). Subgroup and moderator analyses yielded additional clinically informative outcomes. Considering all the possible benefits, music interventions may provide an effective complementary approach for the relief of acute, procedural, and cancer/chronic pain in the medical setting. © the American Music Therapy Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. A meta-analysis of the effects of texting on driving.

    Science.gov (United States)

    Caird, Jeff K; Johnston, Kate A; Willness, Chelsea R; Asbridge, Mark; Steel, Piers

    2014-10-01

    Text messaging while driving is considered dangerous and known to produce injuries and fatalities. However, the effects of text messaging on driving performance have not been synthesized or summarily estimated. All available experimental studies that measured the effects of text messaging on driving were identified through database searches using variants of "driving" and "texting" without restriction on year of publication through March 2014. Of the 1476 abstracts reviewed, 82 met general inclusion criteria. Of these, 28 studies were found to sufficiently compare reading or typing text messages while driving with a control or baseline condition. Independent variables (text-messaging tasks) were coded as typing, reading, or a combination of both. Dependent variables included eye movements, stimulus detection, reaction time, collisions, lane positioning, speed and headway. Statistics were extracted from studies to compute effect sizes (rc). A total sample of 977 participants from 28 experimental studies yielded 234 effect size estimates of the relationships among independent and dependent variables. Typing and reading text messages while driving adversely affected eye movements, stimulus detection, reaction time, collisions, lane positioning, speed and headway. Typing text messages alone produced similar decrements as typing and reading, whereas reading alone had smaller decrements over fewer dependent variables. Typing and reading text messages affects drivers' capability to adequately direct attention to the roadway, respond to important traffic events, control a vehicle within a lane and maintain speed and headway. This meta-analysis provides convergent evidence that texting compromises the safety of the driver, passengers and other road users. Combined efforts, including legislation, enforcement, blocking technologies, parent modeling, social media, social norms and education, will be required to prevent continued deaths and injuries from texting and driving

  10. Effect of Tamsulosin on Stone Passage for Ureteral Stones: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Wang, Ralph C; Smith-Bindman, Rebecca; Whitaker, Evans; Neilson, Jersey; Allen, Isabel Elaine; Stoller, Marshall L; Fahimi, Jahan

    2017-03-01

    Tamsulosin is recommended for patients receiving a diagnosis of a ureteral stone less than 10 mm who do not require immediate urologic intervention. Because of conflicting results from recent meta-analyses and large randomized controlled trials, the efficacy of tamsulosin is unclear. We perform a systematic review and meta-analysis to investigate the effect of tamsulosin on stone passage in patients receiving a diagnosis of ureteral stone. MEDLINE, EMBASE, and CENTRAL databases were searched without language restriction through November 2015 for studies assessing the efficacy of tamsulosin and using a double-blind, randomized, controlled trial design. Meta-analysis was conducted with a random-effects model and subgroup analyses were conducted to determine sources of heterogeneity. Eight randomized controlled trials (N=1,384) contained sufficient information for inclusion. The pooled risk of stone passage in the tamsulosin arm was 85% versus 66% in the placebo arm, but substantial heterogeneity existed across trials (I 2 =80.2%; Ptamsulosin (risk difference=22%; 95% confidence interval 12% to 33%; number needed to treat=5). The meta-analysis of the small stone subgroup (Tamsulosin significantly improves stone passage in patients with larger stones, whereas the effect of tamsulosin is diminished in those with smaller stones, who are likely to pass their stone regardless of treatment. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  11. Psychotherapy for chronic major depression and dysthymia: A meta analysis

    NARCIS (Netherlands)

    Cuijpers, P.; van Straten, A.; Schuurmans, J.; van Oppen, P.C.; Hollon, S.D.; Andersson, G.

    2010-01-01

    Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic depression and

  12. Psychotherapy for chronic major depression and dysthymia: A meta analysis.

    NARCIS (Netherlands)

    Cuijpers, P.; van Straten, A.; Schuurmans, J.; van Oppen, P.C.; Hollon, S.D.; Andersson, G.

    2009-01-01

    Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic depression and

  13. Effect of aromatherapy massage on pain in primary dysmenorrhea: A meta-analysis.

    Science.gov (United States)

    Sut, Necdet; Kahyaoglu-Sut, Hatice

    2017-05-01

    This meta-analysis investigates the effect of aromatherapy massage on pain in primary dysmenorrhea. Randomized controlled trials were searched by keywords in several databases (Pubmed, ISI Web of Sciences, and Google Scholar). Six randomized controlled trials that included 362 participants with primary dysmenorrhea, comparing abdominal aromatherapy massage (n = 184) with massage with placebo oils (n = 178), were analyzed in the meta-analysis. The change in the visual analogue scale (VAS) pain score from the first menstruation cycle to the second cycle at the first menstruation day was used as the primary outcome. Aromatherapy massage with essential oils was superior to massage with placebo oils (standardized mean difference = -1.06 [95% CI: -1.55 to -0.55]). Abdominal aromatherapy massage with essential oils is an effective complementary method to relieve pain in primary dysmenorrhea. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. A meta-analysis of determinants of RFID adoption around the world: Organization, technology, and public policy

    Directory of Open Access Journals (Sweden)

    Sabinne Lee

    2017-01-01

    Full Text Available Purpose - This paper aims to explore various factors associated with radio frequency identification (RFID adoption with quantitative meta-analysis. More specifically, this paper attempts to measure key variables of RFID adoption derived from Rogers’ innovation theory and further examines how state intervention influences the process of RFID adoption. First, this paper compares, relying on a meta-analysis, various mean effect sizes among technological, organizational and environmental factors (i.e. government-driven policies that Rogers suggested in his innovation model. Design/methodology/approach - In mean effect size analysis, this paper finds that the technological factor is the most powerful factor that affects the RFID adoption. The technological factor is statistically significant across all regions, including North America, Europe and Asia. The organizational factor is significant only in developing countries like Southeast Asian countries and East Asian countries. Environmental factors like government intervention for facilitating RFID adoption are strong enough only in Southeast Asia and Europe. Findings - This paper finds that government’s supportive policy is more effective in Europe but not in America, while external pressure is still more effective in Southeast Asia. These results implicate that developmentalism or government-driven policy can be effective not only in developing countries but also in the case of developed countries. In addition, this paper conducts a seemingly unrelated regression (SUR analysis based on Fisher’s standardized score. Originality/value - In SUR analysis, this paper finds that the correlations between RFID adoption intention and three innovation factors vary across industrial areas. More specifically, the manufacturing area shows negative moderating effect on all three equations where correlations between Rogers’ innovation factors and RFID adoption intention are meta-dependent variables. Also

  15. Effects of Botanical Insecticides on Hymenopteran Parasitoids: a Meta-analysis Approach.

    Science.gov (United States)

    Monsreal-Ceballos, R J; Ruiz-Sánchez, E; Ballina-Gómez, H S; Reyes-Ramírez, A; González-Moreno, A

    2018-02-10

    Botanical insecticides (BIs) are considered a valuable alternative for plant protection in sustainable agriculture. The use of both BIs and parasitoids are presumed to be mutually compatible pest management practices. However, there is controversy on this subject, as various studies have reported lethal and sublethal effects of BIs on hymenopteran parasitoids. To shed new light on this controversy, a meta-analytic approach of the effects of BIs on adult mortality, parasitism, and parasitoid emergence under laboratory conditions was performed. We show that BIs increased mortality, decreased parasitism, and decreased parasitoid emergence. Botanical insecticides derived from Nicotiana tabacum and Caceolaria andina were particulary lethal. Most of the parasitoid groups showed susceptibility to BIs, but the families Scelionidae and Ichneumonidae were not significantly affected. The negative effects of BIs were seen regardless of the type of exposure (topical, ingestion, or residual). In conclusion, this meta-analysis showed that under laboratory conditions, exposure of hymenopteran parasitoids to BIs had significant negative effects on adult mortality, parasitism, and parasitoid emergence.

  16. False-positive findings in Cochrane meta-analyses with and without application of trial sequential analysis

    DEFF Research Database (Denmark)

    Imberger, Georgina; Thorlund, Kristian; Gluud, Christian

    2016-01-01

    outcome, a negative result and sufficient power. We defined a negative result as one where the 95% CI for the effect included 1.00, a positive result as one where the 95% CI did not include 1.00, and sufficient power as the required information size for 80% power, 5% type 1 error, relative risk reduction...... of 10% or number needed to treat of 100, and control event proportion and heterogeneity taken from the included studies. We re-conducted the meta-analyses, using conventional cumulative techniques, to measure how many false positives would have occurred if these meta-analyses had been updated after each...... new trial. For each false positive, we performed TSA, using three different approaches. RESULTS: We screened 4736 systematic reviews to find 100 meta-analyses that fulfilled our inclusion criteria. Using conventional cumulative meta-analysis, false positives were present in seven of the meta...

  17. Meta-Analysis of Placental Transcriptome Data Identifies a Novel Molecular Pathway Related to Preeclampsia.

    Science.gov (United States)

    van Uitert, Miranda; Moerland, Perry D; Enquobahrie, Daniel A; Laivuori, Hannele; van der Post, Joris A M; Ris-Stalpers, Carrie; Afink, Gijs B

    2015-01-01

    Studies using the placental transcriptome to identify key molecules relevant for preeclampsia are hampered by a relatively small sample size. In addition, they use a variety of bioinformatics and statistical methods, making comparison of findings challenging. To generate a more robust preeclampsia gene expression signature, we performed a meta-analysis on the original data of 11 placenta RNA microarray experiments, representing 139 normotensive and 116 preeclamptic pregnancies. Microarray data were pre-processed and analyzed using standardized bioinformatics and statistical procedures and the effect sizes were combined using an inverse-variance random-effects model. Interactions between genes in the resulting gene expression signature were identified by pathway analysis (Ingenuity Pathway Analysis, Gene Set Enrichment Analysis, Graphite) and protein-protein associations (STRING). This approach has resulted in a comprehensive list of differentially expressed genes that led to a 388-gene meta-signature of preeclamptic placenta. Pathway analysis highlights the involvement of the previously identified hypoxia/HIF1A pathway in the establishment of the preeclamptic gene expression profile, while analysis of protein interaction networks indicates CREBBP/EP300 as a novel element central to the preeclamptic placental transcriptome. In addition, there is an apparent high incidence of preeclampsia in women carrying a child with a mutation in CREBBP/EP300 (Rubinstein-Taybi Syndrome). The 388-gene preeclampsia meta-signature offers a vital starting point for further studies into the relevance of these genes (in particular CREBBP/EP300) and their concomitant pathways as biomarkers or functional molecules in preeclampsia. This will result in a better understanding of the molecular basis of this disease and opens up the opportunity to develop rational therapies targeting the placental dysfunction causal to preeclampsia.

  18. Conducting Meta-Analysis Using SAS

    CERN Document Server

    Arthur, Winfried; Huffcutt, Allen I; Arthur, Winfred

    2001-01-01

    Conducting Meta-Analysis Using SAS reviews the meta-analysis statistical procedure and shows the reader how to conduct one using SAS. It presents and illustrates the use of the PROC MEANS procedure in SAS to perform the data computations called for by the two most commonly used meta-analytic procedures, the Hunter & Schmidt and Glassian approaches. This book serves as both an operational guide and user's manual by describing and explaining the meta-analysis procedures and then presenting the appropriate SAS program code for computing the pertinent statistics. The practical, step-by-step instru

  19. Effect of Probiotics on Glucose and Lipid Metabolism in Type 2 Diabetes Mellitus: A Meta-Analysis of 12 Randomized Controlled Trials.

    Science.gov (United States)

    Yao, Kecheng; Zeng, Linghai; He, Qian; Wang, Wei; Lei, Jiao; Zou, Xiulan

    2017-06-22

    BACKGROUND It has been unclear whether supplemental probiotics therapy improves clinical outcomes in type 2 diabetic patients. This meta-analysis aimed to summarize the effect of probiotics on glucose and lipid metabolism and C-reactive protein (CRP) from 12 randomized controlled trials (RCTs). MATERIAL AND METHODS An up-to-date search was performed for all relevant RCTs up to April 2016 from PubMed, Embase, and Cochrane Library. Standardized mean difference (SMD) and weighted mean difference (WMD) were calculated for a fixed-effect and random-effect meta-analysis to assess the impact of supplemental probiotics on fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), lipid profile, and CRP level. RESULTS A total of 12 studies (684 patients) were entered into the final analysis. The effect of probiotics was significant on reducing HbA1c level (standardized mean difference [SMD], -0.38; confidence interval [CI], -0.62 to -0.14, P=0.002; I²=0%, P=0.72 for heterogeneity), fasting insulin level (SMD, -0.38; CI -0.59 to -0.18, P=0.0003; I²=0%, P=0.81 for heterogeneity), and HOMA-IR (SMD, -0.99; CI -1.52 to -0.47, P=0.0002; I²=86%, Pprobiotics on FPG, CRP, or lipid profile were either non-significant or highly heterogeneous. CONCLUSIONS This meta-analysis demonstrated that probiotics supplementation was associated with significant improvement in HbA1c and fasting insulin in type 2 diabetes patients. More randomized placebo-controlled trials with large sample sizes are warranted to confirm our conclusions.

  20. Faith-adapted psychological therapies for depression and anxiety: Systematic review and meta-analysis.

    Science.gov (United States)

    Anderson, Naomi; Heywood-Everett, Suzanne; Siddiqi, Najma; Wright, Judy; Meredith, Jodi; McMillan, Dean

    2015-05-01

    Incorporating faith (religious or spiritual) perspectives into psychological treatments has attracted significant interest in recent years. However, previous suggestion that good psychiatric care should include spiritual components has provoked controversy. To try to address ongoing uncertainty in this field we present a systematic review and meta-analysis to assess the efficacy of faith-based adaptations of bona fide psychological therapies for depression or anxiety. A systematic review and meta-analysis of randomised controlled trials were performed. The literature search yielded 2274 citations of which 16 studies were eligible for inclusion. All studies used cognitive or cognitive behavioural models as the basis for their faith-adapted treatment (F-CBT). We identified statistically significant benefits of using F-CBT. However, quality assessment using the Cochrane risk of bias tool revealed methodological limitations that reduce the apparent strength of these findings. Whilst the effect sizes identified here were statistically significant, there were relatively a few relevant RCTs available, and those included were typically small and susceptible to significant biases. Biases associated with researcher or therapist allegiance were identified as a particular concern. Despite some suggestion that faith-adapted CBT may out-perform both standard CBT and control conditions (waiting list or "treatment as usual"), the effect sizes identified in this meta-analysis must be considered in the light of the substantial methodological limitations that affect the primary research data. Before firm recommendations about the value of faith-adapted treatments can be made, further large-scale, rigorously performed trials are required. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Efficacy of intensive versus nonintensive physiotherapy in children with cerebral palsy: a meta-analysis.

    Science.gov (United States)

    Arpino, Carla; Vescio, Maria Fenicia; De Luca, Angela; Curatolo, Paolo

    2010-06-01

    A commonly used treatment for cerebral palsy in children is so-called 'conventional therapy', which includes physiotherapy or the neurodevelopmental approach. Although more intensive rehabilitative treatment is thought to be more effective than less intensive interventions, this assumption has not been proven. In this study we compared the efficacy of intensive versus nonintensive rehabilitative treatment in children with cerebral palsy. A meta-analysis of the studies published between January 1996 and July 2007 was performed. infants/children/adolescents (1-18 years old); randomized controlled trials using, as outcome measure, the Gross Motor Function Measure score. studies that included therapies not generally used in 'so-called' conventional treatment (i.e. constraint, taping). Treatment effects were combined using the weighted mean difference method. Fixed and random effect meta-analyses were carried out and results were compared. Heterogeneity was also assessed. Funnel plots were examined and the presence of small-study effects was tested. Intensive therapy tended to have a greater effect than nonintensive therapy (1.32; 95% confidence interval: 0.55-2.10). The effect of intensive treatment tended to be apparently stronger for children 2 years of age. Our meta-analysis shows that, in children with cerebral palsy, intensive conventional therapy may improve the functional motor outcome, but the effect size seems to be modest.

  2. The relationship between divided attention and implicit memory: a meta-analysis.

    Science.gov (United States)

    Spataro, Pietro; Cestari, Vincenzo; Rossi-Arnaud, Clelia

    2011-03-01

    This article reports a meta-analysis comparing the size of repetition priming in full and divided-attention (DA) conditions. The main analysis included 38 effect sizes (ES) extracted from 21 empirical studies, for a total of 2074 (full-attention) and 2148 (divided-attention) participants. The mean weighted ES was 0.357 (95% CI=0.278-0.435), indicating that divided attention produced a small, but significant, negative effect on implicit memory. Overall, the distinction between identification and production priming provided the best fit to empirical data (with the effect of DA being greater for production tests), whereas there was no significant difference between perceptual and conceptual priming. A series of focused contrasts suggested that word-stem completion might be influenced by lexical-conceptual processes, and that perceptual identification might involve a productive component. Implications for current theories of implicit memory are discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. The efficacy of cognitive behavioral therapy for Chinese people: A meta-analysis.

    Science.gov (United States)

    Ng, Ting Kin; Wong, Daniel Fu Keung

    2018-07-01

    Over the past decade, cognitive behavioral therapy has been applied to an increasingly wider range of disorders and problems in Chinese societies. However, no meta-analysis has been conducted to synthesize the studies on cognitive behavioral therapy for Chinese clients. The purpose of this meta-analytic study was to examine the overall efficacy of cognitive behavioral therapy for Chinese people. A literature search was conducted using electronic databases, including Web of Science, PsycINFO and PubMed. Pooled mean effect sizes were calculated using the random-effects model. The literature search identified 55 studies with 6763 Chinese participants. The overall short-term effect of cognitive behavioral therapy on the primary outcome was medium in size. Effect sizes were medium for anxiety, depression/well-being and caregiving stress and small for psychotic symptoms and addictive behaviors. The effects of cognitive behavioral therapy on process variables, dysfunctional thoughts and coping, were in the small range. The overall longer-term effect of cognitive behavioral therapy on the primary outcome was medium in size. Moderator analyses showed that the short-term effect was stronger for culturally adapted cognitive behavioral therapy than for unadapted cognitive behavioral therapy. Type of primary outcome, type of control group, recruitment method, study design, the format of delivery and region were found to moderate the efficacy of cognitive behavioral therapy. The findings of this study provide evidence for the overall efficacy of cognitive behavioral therapy for Chinese people and the benefit of cultural adaptation of cognitive behavioral therapy to Chinese culture.

  4. The five-factor model of personality traits and organizational citizenship behaviors: a meta-analysis.

    Science.gov (United States)

    Chiaburu, Dan S; Oh, In-Sue; Berry, Christopher M; Li, Ning; Gardner, Richard G

    2011-11-01

    Using meta-analytic tests based on 87 statistically independent samples, we investigated the relationships between the five-factor model (FFM) of personality traits and organizational citizenship behaviors in both the aggregate and specific forms, including individual-directed, organization-directed, and change-oriented citizenship. We found that Emotional Stability, Extraversion, and Openness/Intellect have incremental validity for citizenship over and above Conscientiousness and Agreeableness, 2 well-established FFM predictors of citizenship. In addition, FFM personality traits predict citizenship over and above job satisfaction. Finally, we compared the effect sizes obtained in the current meta-analysis with the comparable effect sizes predicting task performance from previous meta-analyses. As a result, we found that Conscientiousness, Emotional Stability, and Extraversion have similar magnitudes of relationships with citizenship and task performance, whereas Openness and Agreeableness have stronger relationships with citizenship than with task performance. This lends some support to the idea that personality traits are (slightly) more important determinants of citizenship than of task performance. We conclude with proposed directions for future research on the relationships between FFM personality traits and specific forms of citizenship, based on the current findings. (c) 2011 APA, all rights reserved.

  5. Visual Task Demands and the Auditory Mismatch Negativity: An Empirical Study and a Meta-Analysis.

    Science.gov (United States)

    Wiens, Stefan; Szychowska, Malina; Nilsson, Mats E

    2016-01-01

    Because the auditory system is particularly useful in monitoring the environment, previous research has examined whether task-irrelevant, auditory distracters are processed even if subjects focus their attention on visual stimuli. This research suggests that attentionally demanding visual tasks decrease the auditory mismatch negativity (MMN) to simultaneously presented auditory distractors. Because a recent behavioral study found that high visual perceptual load decreased detection sensitivity of simultaneous tones, we used a similar task (n = 28) to determine if high visual perceptual load would reduce the auditory MMN. Results suggested that perceptual load did not decrease the MMN. At face value, these nonsignificant findings may suggest that effects of perceptual load on the MMN are smaller than those of other demanding visual tasks. If so, effect sizes should differ systematically between the present and previous studies. We conducted a selective meta-analysis of published studies in which the MMN was derived from the EEG, the visual task demands were continuous and varied between high and low within the same task, and the task-irrelevant tones were presented in a typical oddball paradigm simultaneously with the visual stimuli. Because the meta-analysis suggested that the present (null) findings did not differ systematically from previous findings, the available evidence was combined. Results of this meta-analysis confirmed that demanding visual tasks reduce the MMN to auditory distracters. However, because the meta-analysis was based on small studies and because of the risk for publication biases, future studies should be preregistered with large samples (n > 150) to provide confirmatory evidence for the results of the present meta-analysis. These future studies should also use control conditions that reduce confounding effects of neural adaptation, and use load manipulations that are defined independently from their effects on the MMN.

  6. Visual Task Demands and the Auditory Mismatch Negativity: An Empirical Study and a Meta-Analysis

    Science.gov (United States)

    Wiens, Stefan; Szychowska, Malina; Nilsson, Mats E.

    2016-01-01

    Because the auditory system is particularly useful in monitoring the environment, previous research has examined whether task-irrelevant, auditory distracters are processed even if subjects focus their attention on visual stimuli. This research suggests that attentionally demanding visual tasks decrease the auditory mismatch negativity (MMN) to simultaneously presented auditory distractors. Because a recent behavioral study found that high visual perceptual load decreased detection sensitivity of simultaneous tones, we used a similar task (n = 28) to determine if high visual perceptual load would reduce the auditory MMN. Results suggested that perceptual load did not decrease the MMN. At face value, these nonsignificant findings may suggest that effects of perceptual load on the MMN are smaller than those of other demanding visual tasks. If so, effect sizes should differ systematically between the present and previous studies. We conducted a selective meta-analysis of published studies in which the MMN was derived from the EEG, the visual task demands were continuous and varied between high and low within the same task, and the task-irrelevant tones were presented in a typical oddball paradigm simultaneously with the visual stimuli. Because the meta-analysis suggested that the present (null) findings did not differ systematically from previous findings, the available evidence was combined. Results of this meta-analysis confirmed that demanding visual tasks reduce the MMN to auditory distracters. However, because the meta-analysis was based on small studies and because of the risk for publication biases, future studies should be preregistered with large samples (n > 150) to provide confirmatory evidence for the results of the present meta-analysis. These future studies should also use control conditions that reduce confounding effects of neural adaptation, and use load manipulations that are defined independently from their effects on the MMN. PMID:26741815

  7. Beta-binomial model for meta-analysis of odds ratios.

    Science.gov (United States)

    Bakbergenuly, Ilyas; Kulinskaya, Elena

    2017-05-20

    In meta-analysis of odds ratios (ORs), heterogeneity between the studies is usually modelled via the additive random effects model (REM). An alternative, multiplicative REM for ORs uses overdispersion. The multiplicative factor in this overdispersion model (ODM) can be interpreted as an intra-class correlation (ICC) parameter. This model naturally arises when the probabilities of an event in one or both arms of a comparative study are themselves beta-distributed, resulting in beta-binomial distributions. We propose two new estimators of the ICC for meta-analysis in this setting. One is based on the inverted Breslow-Day test, and the other on the improved gamma approximation by Kulinskaya and Dollinger (2015, p. 26) to the distribution of Cochran's Q. The performance of these and several other estimators of ICC on bias and coverage is studied by simulation. Additionally, the Mantel-Haenszel approach to estimation of ORs is extended to the beta-binomial model, and we study performance of various ICC estimators when used in the Mantel-Haenszel or the inverse-variance method to combine ORs in meta-analysis. The results of the simulations show that the improved gamma-based estimator of ICC is superior for small sample sizes, and the Breslow-Day-based estimator is the best for n⩾100. The Mantel-Haenszel-based estimator of OR is very biased and is not recommended. The inverse-variance approach is also somewhat biased for ORs≠1, but this bias is not very large in practical settings. Developed methods and R programs, provided in the Web Appendix, make the beta-binomial model a feasible alternative to the standard REM for meta-analysis of ORs. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

  8. Dissociation between recognition and detection advantage for facial expressions: a meta-analysis.

    Science.gov (United States)

    Nummenmaa, Lauri; Calvo, Manuel G

    2015-04-01

    Happy facial expressions are recognized faster and more accurately than other expressions in categorization tasks, whereas detection in visual search tasks is widely believed to be faster for angry than happy faces. We used meta-analytic techniques for resolving this categorization versus detection advantage discrepancy for positive versus negative facial expressions. Effect sizes were computed on the basis of the r statistic for a total of 34 recognition studies with 3,561 participants and 37 visual search studies with 2,455 participants, yielding a total of 41 effect sizes for recognition accuracy, 25 for recognition speed, and 125 for visual search speed. Random effects meta-analysis was conducted to estimate effect sizes at population level. For recognition tasks, an advantage in recognition accuracy and speed for happy expressions was found for all stimulus types. In contrast, for visual search tasks, moderator analysis revealed that a happy face detection advantage was restricted to photographic faces, whereas a clear angry face advantage was found for schematic and "smiley" faces. Robust detection advantage for nonhappy faces was observed even when stimulus emotionality was distorted by inversion or rearrangement of the facial features, suggesting that visual features primarily drive the search. We conclude that the recognition advantage for happy faces is a genuine phenomenon related to processing of facial expression category and affective valence. In contrast, detection advantages toward either happy (photographic stimuli) or nonhappy (schematic) faces is contingent on visual stimulus features rather than facial expression, and may not involve categorical or affective processing. (c) 2015 APA, all rights reserved).

  9. Effect of Probiotics on Depression: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

    Directory of Open Access Journals (Sweden)

    Ruixue Huang

    2016-08-01

    Full Text Available It has been reported that gut probiotics play a major role in the bidirectional communication between the gut and the brain. Probiotics may be essential to people with depression, which remains a global health challenge, as depression is a metabolic brain disorder. However, the efficacy of probiotics for depression is controversial. This study aimed to systematically review the existing evidence on the effect of probiotics-based interventions on depression. Randomized, controlled trials, identified through screening multiple databases and grey literature, were included in the meta-analysis. The meta-analysis was performed using Review Manager 5.3 software using a fixed-effects model. The meta-analysis showed that probiotics significantly decreased the depression scale score (MD (depressive disorder = −0.30, 95% CI (−0.51–−0.09, p = 0.005 in the subjects. Probiotics had an effect on both the healthy population (MD = −0.25, 95% CI (−0.47–−0.03, p = 0.03 and patients with major depressive disorder (MDD (MD = −0.73, 95% CI (−1.37–−0.09, p = 0.03. Probiotics had an effect on the population aged under 60 (MD = −0.43, 95% CI (−0.72–−0.13, p = 0.005, while it had no effect on people aged over 65 (MD = −0.18, 95% CI (−0.47–0.11, p = 0.22. This is the first systematic review and meta-analysis with the goal of determining the effect of probiotics on depression. We found that probiotics were associated with a significant reduction in depression, underscoring the need for additional research on this potential preventive strategy for depression.

  10. A meta-analysis of motivational interviewing process: Technical, relational, and conditional process models of change.

    Science.gov (United States)

    Magill, Molly; Apodaca, Timothy R; Borsari, Brian; Gaume, Jacques; Hoadley, Ariel; Gordon, Rebecca E F; Tonigan, J Scott; Moyers, Theresa

    2018-02-01

    In the present meta-analysis, we test the technical and relational hypotheses of Motivational Interviewing (MI) efficacy. We also propose an a priori conditional process model where heterogeneity of technical path effect sizes should be explained by interpersonal/relational (i.e., empathy, MI Spirit) and intrapersonal (i.e., client treatment seeking status) moderators. A systematic review identified k = 58 reports, describing 36 primary studies and 40 effect sizes (N = 3,025 participants). Statistical methods calculated the inverse variance-weighted pooled correlation coefficient for the therapist to client and the client to outcome paths across multiple target behaviors (i.e., alcohol use, other drug use, other behavior change). Therapist MI-consistent skills were correlated with more client change talk (r = .55, p technical hypothesis was supported. Specifically, proportion MI consistency was related to higher proportion change talk (r = .11, p = .004) and higher proportion change talk was related to reductions in risk behavior at follow up (r = -.16, p technical hypothesis path effect sizes was partially explained by inter- and intrapersonal moderators. This meta-analysis provides additional support for the technical hypothesis of MI efficacy; future research on the relational hypothesis should occur in the field rather than in the context of clinical trials. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  11. Social attention in ASD: A review and meta-analysis of eye-tracking studies.

    Science.gov (United States)

    Chita-Tegmark, Meia

    2016-01-01

    Determining whether social attention is reduced in Autism Spectrum Disorder (ASD) and what factors influence social attention is important to our theoretical understanding of developmental trajectories of ASD and to designing targeted interventions for ASD. This meta-analysis examines data from 38 articles that used eye-tracking methods to compare individuals with ASD and TD controls. In this paper, the impact of eight factors on the size of the effect for the difference in social attention between these two groups are evaluated: age, non-verbal IQ matching, verbal IQ matching, motion, social content, ecological validity, audio input and attention bids. Results show that individuals with ASD spend less time attending to social stimuli than typically developing (TD) controls, with a mean effect size of 0.55. Social attention in ASD was most impacted when stimuli had a high social content (showed more than one person). This meta-analysis provides an opportunity to survey the eye-tracking research on social attention in ASD and to outline potential future research directions, more specifically research of social attention in the context of stimuli with high social content. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effectiveness of massage therapy on the range of motion of the shoulder: a systematic review and meta-analysis.

    Science.gov (United States)

    Yeun, Young-Ran

    2017-02-01

    [Purpose] This study was conducted to identify and analyze the degree of effect of massage therapy on the range of motion of the shoulder. [Subjects and Methods] The database search was conducted using PubMed, CINAHL, Embase, PsycINFO, RISS, NDSL, NANET, DBpia, and KoreaMed. The meta-analysis was based on 7 studies, covered a total of 237 participants, and used a random-effects model. [Results] The effect size estimate showed that massage therapy significantly improved the shoulder range of motion, especially the flexion (SMD: 18.21, 95% CI 1.57-34.85) and abduction (SMD: 22.07, 95% CI 5.84-38.30). [Conclusion] The review findings suggest that massage therapy is effective in improving the shoulder flexion and abduction.

  13. Personality and Parkinson's disease: A meta-analysis.

    Science.gov (United States)

    Santangelo, Gabriella; Garramone, Federica; Baiano, Chiara; D'Iorio, Alfonsina; Piscopo, Fausta; Raimo, Simona; Vitale, Carmine

    2018-04-01

    Personality changes are considered pre-motor features of Parkinson's disease (PD). Cross-sectional studies revealed that PD patients were more introvert, apprehensive, and cautious than healthy subjects (HS), whereas other studies failed to disclose these behavioural traits. Some studies found mixed results concerning Novelty Seeking (NS) and Harm Avoidance (HA) profiles in PD patients. To better clarify the personality profile in PD we performed a meta-analysis on studies exploring such topic according to both Cloninger's Psychobiological Model (PM) and Big Five Model (BFM) METHODS: The meta-analysis included 17 studies evaluating the personality in PD patients compared with HS. The outcomes were the dimensions of the temperament and character of the PM and personality traits of BFM. Effect sizes from data reported in the primary studies were computed using Hedges'g unbiased approach. Heterogeneity among the studies and publication bias were assessed. Meta-regressions were conducted with age at evaluation, gender, schooling, and type of personality trait tools as moderators. As for PM, PD patients scored higher on HA and lower on NS than HS. No difference was found on Reward Dependence, Perseverance/Persistence and on character level. As for BFM, higher levels of Neuroticism, but lower levels of Openness and Extraversion were associated with PD. The personality profile in PD is characterized by high Neuroticism and HA, and by low Openness, Extraversion and NS. The personality profile delineated in the present study on PD patients seems to reflect the premorbid one and might contribute to development and persistence of affective disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Complementary and alternative exercise for fibromyalgia: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Mist SD

    2013-03-01

    Full Text Available Scott David Mist, Kari Firestone, Kim Dupree Jones Fibromyalgia Research and Treatment Group, School of Nursing, Oregon Health and Science University, Portland, OR, USA Abstract: Complementary and alternative medicine includes a number of exercise modalities, such as tai chi, qigong, yoga, and a variety of lesser-known movement therapies. A meta-analysis of the current literature was conducted estimating the effect size of the different modalities, study quality and bias, and adverse events. The level of research has been moderately weak to date, but most studies report a medium-to-high effect size in pain reduction. Given the lack of adverse events, there is little risk in recommending these modalities as a critical component in a multimodal treatment plan, which is often required for fibromyalgia management. Keywords: fibromyalgia, exercise, complementary and alternative, efficacy, safety

  15. Curcuminoids Lower Plasma Leptin Concentrations: A Meta-analysis.

    Science.gov (United States)

    Atkin, Stephen L; Katsiki, Niki; Derosa, Giuseppe; Maffioli, Pamela; Sahebkar, Amirhossein

    2017-12-01

    Curcumin is a naturally occurring polyphenol that has been suggested to improve several metabolic diseases. Leptin is an adipokine involved in metabolic status and appetite, with marked crosstalk with other systems. Available data suggest that curcumin may affect leptin levels; therefore, this meta-analysis was performed to evaluate this. A systematic review and meta-analysis were undertaken on all randomized controlled trials of curcumin studies that included the measurement of leptin. The search included PubMed-Medline, Scopus, ISI Web of Knowledge, and Google Scholar databases. Quantitative data synthesis was performed by using a random-effects model, with standardized mean difference and 95% confidence interval as summary statistics. A funnel plot, Begg's rank correlation, and Egger's weighted regression tests assessed the presence of publication bias. Four eligible articles comprising five treatment arms were selected for the meta-analysis. Meta-analysis showed a significant decrease in plasma leptin concentrations following curcumin treatment (standardized mean difference: -0.69, 95% confidence interval: -1.16, -0.23, p = 0.003; I 2  = 76.53%). There was no evidence of publication bias. This meta-analysis showed that curcumin supplementation is associated with a decrease in leptin levels that may be regarded as a potential mechanism for the metabolic effects of curcumin. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  16. A meta-analysis of effects of post-hatch food and water deprivation on development, performance and welfare of chickens

    NARCIS (Netherlands)

    Jong, de I.C.; Riel, van J.W.; Bracke, M.B.M.; Brand, van den H.

    2017-01-01

    A ‘meta-analysis’ was performed to determine effects of post-hatch food and water deprivation (PHFWD) on chicken development, performance and welfare (including health). Two types of meta-analysis were performed on peer-reviewed scientific publications: a quantitative ‘meta-analysis’ (MA) and a

  17. Educational Impacts and Cost-Effectiveness of Conditional Cash Transfer Programs in Developing Countries: A Meta-Analysis

    Science.gov (United States)

    García, Sandra; Saavedra, Juan E.

    2017-01-01

    We meta-analyze for impact and cost-effectiveness 94 studies from 47 conditional cash transfer programs in low- and middle-income countries worldwide, focusing on educational outcomes that include enrollment, attendance, dropout, and school completion. To conceptually guide and interpret the empirical findings of our meta-analysis, we present a…

  18. Physical therapy treatments for low back pain in children and adolescents: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Calvo-Muñoz Inmaculada

    2013-02-01

    Full Text Available Abstract Background Low back pain (LBP in adolescents is associated with LBP in later years. In recent years treatments have been administered to adolescents for LBP, but it is not known which physical therapy treatment is the most efficacious. By means of a meta-analysis, the current study investigated the effectiveness of the physical therapy treatments for LBP in children and adolescents. Methods Studies in English, Spanish, French, Italian and Portuguese, and carried out by March 2011, were selected by electronic and manual search. Two independent researchers coded the moderator variables of the studies, and performed the effect size calculations. The mean effect size index used was the standardized mean change between the pretest and posttest, and it was applied separately for each combination of outcome measures, (pain, disability, flexibility, endurance and mental health and measurement type (self-reports, and clinician assessments. Results Eight articles that met the selection criteria enabled us to define 11 treatment groups and 5 control groups using the group as the unit of analysis. The 16 groups involved a total sample of 334 subjects at the posttest (221 in the treatment groups and 113 in the control groups. For all outcome measures, the average effect size of the treatment groups was statistically and clinically significant, whereas the control groups had negative average effect sizes that were not statistically significant. Conclusions Of all the physical therapy treatments for LBP in children and adolescents, the combination of therapeutic physical conditioning and manual therapy is the most effective. The low number of studies and control groups, and the methodological limitations in this meta-analysis prevent us from drawing definitive conclusions in relation to the efficacy of physical therapy treatments in LBP.

  19. Causal Meta-Analysis : Methodology and Applications

    NARCIS (Netherlands)

    Bax, L.J.

    2009-01-01

    Meta-analysis is a statistical method to summarize research data from multiple studies in a quantitative manner. This dissertation addresses a number of methodological topics in causal meta-analysis and reports the development and validation of meta-analysis software. In the first (methodological)

  20. A Meta-Analysis Summarizing the Effects of Pornography II: Aggression after Exposure.

    Science.gov (United States)

    Allen, Mike; And Others

    1995-01-01

    Examines by meta-analysis the effect that exposure to pornography produces on aggressive behavior under laboratory conditions considering a variety of possible moderating conditions. Demonstrates a homogeneous set of results showing that pictorial nudity reduces subsequent violent behavior, but that depictions of nonviolent sexual behavior and…

  1. Age differences in the effect of framing on risky choice: A meta-analysis

    Science.gov (United States)

    Best, Ryan; Charness, Neil

    2015-01-01

    The framing of decision scenarios in terms of potential gains versus losses has been shown to influence choice preferences between sure and risky options. Normative cognitive changes associated with aging have been known to affect decision-making, which has led to a number of studies investigating the influence of aging on the effect of framing. Mata, Josef, Samanez-Larkin, and Hertwig (2011) systematically reviewed the available literature using a meta-analytic approach, but did not include tests of homogeneity nor subsequent moderator variable analyses. The current review serves to extend the previous analysis to include such tests as well as update the pool of studies available for analysis. Results for both positively and negatively framed conditions were reviewed using two meta-analyses encompassing data collected from 3,232 subjects across 18 studies. Deviating from the previous results, the current analysis finds a tendency for younger adults to choose the risky option more often than older adults for positively framed items. Moderator variable analyses find this effect to likely be driven by the specific decision scenario, showing a significant effect with younger adults choosing the risky option more often in small-amount financial and large-amount mortality-based scenarios. For negatively framed items, the current review found no overall age difference in risky decision making, confirming the results from the prior meta-analysis. Moderator variable analyses conducted to address heterogeneity found younger adults to be more likely than older adults to choose the risky option for negatively framed high-amount mortality-based decision scenarios. Practical implications for older adults are discussed. PMID:26098168

  2. Self-Determination Theory Applied to Health Contexts: A Meta-Analysis.

    Science.gov (United States)

    Ng, Johan Y Y; Ntoumanis, Nikos; Thøgersen-Ntoumani, Cecilie; Deci, Edward L; Ryan, Richard M; Duda, Joan L; Williams, Geoffrey C

    2012-07-01

    Behavior change is more effective and lasting when patients are autonomously motivated. To examine this idea, we identified 184 independent data sets from studies that utilized self-determination theory (SDT; Deci & Ryan, 2000) in health care and health promotion contexts. A meta-analysis evaluated relations between the SDT-based constructs of practitioner support for patient autonomy and patients' experience of psychological need satisfaction, as well as relations between these SDT constructs and indices of mental and physical health. Results showed the expected relations among the SDT variables, as well as positive relations of psychological need satisfaction and autonomous motivation to beneficial health outcomes. Several variables (e.g., participants' age, study design) were tested as potential moderators when effect sizes were heterogeneous. Finally, we used path analyses of the meta-analyzed correlations to test the interrelations among the SDT variables. Results suggested that SDT is a viable conceptual framework to study antecedents and outcomes of motivation for health-related behaviors. © The Author(s) 2012.

  3. Sixty Years of Placebo-Controlled Antipsychotic Drug Trials in Acute Schizophrenia: Systematic Review, Bayesian Meta-Analysis, and Meta-Regression of Efficacy Predictors.

    Science.gov (United States)

    Leucht, Stefan; Leucht, Claudia; Huhn, Maximilian; Chaimani, Anna; Mavridis, Dimitris; Helfer, Bartosz; Samara, Myrto; Rabaioli, Matteo; Bächer, Susanne; Cipriani, Andrea; Geddes, John R; Salanti, Georgia; Davis, John M

    2017-10-01

    Antipsychotic drug efficacy may have decreased over recent decades. The authors present a meta-analysis of all placebo-controlled trials in patients with acute exacerbations of schizophrenia, and they investigate which trial characteristics have changed over the years and which are moderators of drug-placebo efficacy differences. The search included multiple electronic databases. The outcomes were overall efficacy (primary outcome); responder and dropout rates; positive, negative, and depressive symptoms; quality of life; functioning; and major side effects. Potential moderators of efficacy were analyzed by meta-regression. The analysis included 167 double-blind randomized controlled trials with 28,102 mainly chronic participants. The standardized mean difference (SMD) for overall efficacy was 0.47 (95% credible interval 0.42, 0.51), but accounting for small-trial effects and publication bias reduced the SMD to 0.38. At least a "minimal" response occurred in 51% of the antipsychotic group versus 30% in the placebo group, and 23% versus 14% had a "good" response. Positive symptoms (SMD 0.45) improved more than negative symptoms (SMD 0.35) and depression (SMD 0.27). Quality of life (SMD 0.35) and functioning (SMD 0.34) improved even in the short term. Antipsychotics differed substantially in side effects. Of the response predictors analyzed, 16 trial characteristics changed over the decades. However, in a multivariable meta-regression, only industry sponsorship and increasing placebo response were significant moderators of effect sizes. Drug response remained stable over time. Approximately twice as many patients improved with antipsychotics as with placebo, but only a minority experienced a good response. Effect sizes were reduced by industry sponsorship and increasing placebo response, not decreasing drug response. Drug development may benefit from smaller samples but better-selected patients.

  4. Meta-analysis a structural equation modeling approach

    CERN Document Server

    Cheung, Mike W-L

    2015-01-01

    Presents a novel approach to conducting meta-analysis using structural equation modeling. Structural equation modeling (SEM) and meta-analysis are two powerful statistical methods in the educational, social, behavioral, and medical sciences. They are often treated as two unrelated topics in the literature. This book presents a unified framework on analyzing meta-analytic data within the SEM framework, and illustrates how to conduct meta-analysis using the metaSEM package in the R statistical environment. Meta-Analysis: A Structural Equation Modeling Approach begins by introducing the impo

  5. Can chocolate consumption reduce cardio-cerebrovascular risk? A systematic review and meta-analysis.

    Science.gov (United States)

    Gianfredi, Vincenza; Salvatori, Tania; Nucci, Daniele; Villarini, Milena; Moretti, Massimo

    2018-02-01

    A systematic review and meta-analysis of the literature was performed to assess the relationship between chocolate intake and cardio-cerebrovascular risk in the general population. A structured search of the literature was performed in the PubMed database up to September 26, 2016, using predetermined keywords. Epidemiologic studies evaluating the risk for cardiovascular diseases (CVDs; i.e., stroke, acute myocardial infarction [MI], heart failure, coronary heart disease) were included according to different rates of chocolate intake. The software ProMeta 3 was used to perform the meta-analysis. The systematic review identified 16 eligible studies. The majority of the studies showed a protective effect of chocolate intake compared with unexposed individuals. The overall risk ratio (effect size [ES]) of CVD for the highest versus the lowest category of chocolate consumption was 0.77 (95% confidence interval [CI], 0.71-0.84; P = 0.000) with a moderate heterogeneity. The risk related to subgroups of CVD and in particular, the risk for MI was further analyzed: ES = 0.78 (95% CI, 0.64-0.94; P = 0.009) without statistical heterogeneity (I 2  = 46.56%; P = 0.13). Moreover, the analysis performed based on sex found an ES = 0.85 (95% CI, 0.77-0.95; P = 0.003) for women, with a very low grade of heterogeneity (I 2  = 62.21%; P = 0.005). The results of the meta-analysis showed a potential protective effect of moderate consumption of chocolate on cardiovascular risk, especially for women, and against MI for both sexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. MetaMeta: integrating metagenome analysis tools to improve taxonomic profiling.

    Science.gov (United States)

    Piro, Vitor C; Matschkowski, Marcel; Renard, Bernhard Y

    2017-08-14

    Many metagenome analysis tools are presently available to classify sequences and profile environmental samples. In particular, taxonomic profiling and binning methods are commonly used for such tasks. Tools available among these two categories make use of several techniques, e.g., read mapping, k-mer alignment, and composition analysis. Variations on the construction of the corresponding reference sequence databases are also common. In addition, different tools provide good results in different datasets and configurations. All this variation creates a complicated scenario to researchers to decide which methods to use. Installation, configuration and execution can also be difficult especially when dealing with multiple datasets and tools. We propose MetaMeta: a pipeline to execute and integrate results from metagenome analysis tools. MetaMeta provides an easy workflow to run multiple tools with multiple samples, producing a single enhanced output profile for each sample. MetaMeta includes a database generation, pre-processing, execution, and integration steps, allowing easy execution and parallelization. The integration relies on the co-occurrence of organisms from different methods as the main feature to improve community profiling while accounting for differences in their databases. In a controlled case with simulated and real data, we show that the integrated profiles of MetaMeta overcome the best single profile. Using the same input data, it provides more sensitive and reliable results with the presence of each organism being supported by several methods. MetaMeta uses Snakemake and has six pre-configured tools, all available at BioConda channel for easy installation (conda install -c bioconda metameta). The MetaMeta pipeline is open-source and can be downloaded at: https://gitlab.com/rki_bioinformatics .

  7. Effects of Basal Defoliation on Wine Aromas: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2018-03-01

    Full Text Available Basal defoliation, as one of the most common viticulture management practices to modify fruit zone microclimates, has been widely applied aiming at improving wine quality. Wine aroma contributes greatly to wine quality, yet the effects of basal defoliation on wine aromas show discrepancies according to previous studies. This study is a meta-analysis performed to dissect the factors related to the influence of basal defoliation on volatile compounds in wine. Timing of basal defoliation plays an important role in the concentration of varietal aromas in wine. Pre-veraison defoliation induces an increase in β-damascenone and linalool as well as a reduction in 3-isobutyl-2-methoxypyrazine (IBMP. The effects of basal defoliation on certain volatile compounds relative to fermentation aromas in wine (1-hexanol, β-phenylethanol, 2-phenylethyl acetate, decanoic acid, and ethyl octanoate depend on grape maturity. There are also other factors, such as cultivar and climate conditions, that might be responsible for the effect of basal defoliation on wine aromas. The concentrations of isobutanol, isoamyl alcohol, hexanoic acid, and octanoic acid as well as ethyl isobutyrate, ethyl hexanoate, ethyl isovalerate, and ethyl decanoate in wine are not markedly affected by basal defoliation. Due to limited studies included in this meta-analysis, more trials are needed to confirm the current findings.

  8. Comparative effectiveness of instructional design features in simulation-based education: systematic review and meta-analysis.

    Science.gov (United States)

    Cook, David A; Hamstra, Stanley J; Brydges, Ryan; Zendejas, Benjamin; Szostek, Jason H; Wang, Amy T; Erwin, Patricia J; Hatala, Rose

    2013-01-01

    Although technology-enhanced simulation is increasingly used in health professions education, features of effective simulation-based instructional design remain uncertain. Evaluate the effectiveness of instructional design features through a systematic review of studies comparing different simulation-based interventions. We systematically searched MEDLINE, EMBASE, CINAHL, ERIC, PsycINFO, Scopus, key journals, and previous review bibliographies through May 2011. We included original research studies that compared one simulation intervention with another and involved health professions learners. Working in duplicate, we evaluated study quality and abstracted information on learners, outcomes, and instructional design features. We pooled results using random effects meta-analysis. From a pool of 10,903 articles we identified 289 eligible studies enrolling 18,971 trainees, including 208 randomized trials. Inconsistency was usually large (I2 > 50%). For skills outcomes, pooled effect sizes (positive numbers favoring the instructional design feature) were 0.68 for range of difficulty (20 studies; p simulation-based education.

  9. Effectiveness and feasibility of hysteroscopic sterilization techniques: a systematic review and meta-analysis

    NARCIS (Netherlands)

    la Chapelle, C.F.; Veersema, S.; Brölmann, H.A.M.; Jansen, F.W.

    2015-01-01

    Objective To assess whether hysteroscopic sterilization is feasible and effective in preventing pregnancy. Secondarily, to identify risk factors for failure of hysteroscopic sterilization. Design A systematic review and meta-analysis. Setting Not applicable. Patient(s) Women undergoing hysteroscopic

  10. Evaluating the Effect of Virtual Reality Temporal Bone Simulation on Mastoidectomy Performance: A Meta-analysis.

    Science.gov (United States)

    Lui, Justin T; Hoy, Monica Y

    2017-06-01

    Background The increasing prevalence of virtual reality simulation in temporal bone surgery warrants an investigation to assess training effectiveness. Objectives To determine if temporal bone simulator use improves mastoidectomy performance. Data Sources Ovid Medline, Embase, and PubMed databases were systematically searched per the PRISMA guidelines. Review Methods Inclusion criteria were peer-reviewed publications that utilized quantitative data of mastoidectomy performance following the use of a temporal bone simulator. The search was restricted to human studies published in English. Studies were excluded if they were in non-peer-reviewed format, were descriptive in nature, or failed to provide surgical performance outcomes. Meta-analysis calculations were then performed. Results A meta-analysis based on the random-effects model revealed an improvement in overall mastoidectomy performance following training on the temporal bone simulator. A standardized mean difference of 0.87 (95% CI, 0.38-1.35) was generated in the setting of a heterogeneous study population ( I 2 = 64.3%, P virtual reality simulation temporal bone surgery studies, meta-analysis calculations demonstrate an improvement in trainee mastoidectomy performance with virtual simulation training.

  11. Mobile phone SMS messages can enhance healthy behaviour: a meta-analysis of randomised controlled trials.

    Science.gov (United States)

    Orr, Jayne A; King, Robert J

    2015-01-01

    Healthy behaviour, such as smoking cessation and adherence to prescribed medications, mitigates illness risk factors but health behaviour change can be challenging. Mobile phone short-message service (SMS) messages are increasingly used to deliver interventions designed to enhance healthy behaviour. This meta-analysis used a random-effects model to synthesise 38 randomised controlled trials that investigated the efficacy of SMS messages to enhance healthy behaviour. Participants (N = 19,641) lived in developed and developing countries and were diverse with respect to age, ethnicity, socioeconomic background and health behaviours targeted for change. SMS messages had a small, positive, significant effect (g = 0.291) on a broad range of healthy behaviour. This effect was maximised when multiple SMS messages per day were used (g = 0.395) compared to using lower frequencies (daily, multiple per week and once-off) (g = 0.244). The low heterogeneity in this meta-analysis (I (2) = 38.619) supports reporting a summary effect size and implies that the effect of SMS messaging is robust, regardless of population characteristics or healthy behaviour targeted. SMS messaging is a simple, cost-effective intervention that can be automated and can reach any mobile phone owner. While the effect size is small, potential health benefits are well worth achieving.

  12. Magnitude of cognitive dysfunction in adults with type 2 diabetes: a meta-analysis of six cognitive domains and the most frequently reported neuropsychological tests within domains

    NARCIS (Netherlands)

    Palta, P.; Schneider, A.; Biessels, G.J.; Touradji, P.; Hill-Briggs, F.

    2014-01-01

    The objectives were to conduct a meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards to determine effect sizes (Cohen’s d) for cognitive dysfunction in adults with type 2 diabetes, relative to nondiabetic controls, and to obtain

  13. Effectiveness of Reirradiation for Painful Bone Metastases: A Systematic Review and Meta-Analysis

    International Nuclear Information System (INIS)

    Huisman, Merel; Bosch, Maurice A.A.J. van den; Wijlemans, Joost W.; Vulpen, Marco van; Linden, Yvette M. van der; Verkooijen, Helena M.

    2012-01-01

    Purpose: Reirradiation of painful bone metastases in nonresponders or patients with recurrent pain after initial response is performed in up to 42% of patients initially treated with radiotherapy. Literature on the effect of reirradiation for pain control in those patients is scarce. In this systematic review and meta-analysis, we quantify the effectiveness of reirradiation for achieving pain control in patients with painful bone metastases. Methods and Materials: A free text search was performed to identify eligible studies using the MEDLINE, EMBASE, and the Cochrane Collaboration library electronic databases. After study selection and quality assessment, a pooled estimate was calculated for overall pain response for reirradiation of metastatic bone pain. Results: Our literature search identified 707 titles, of which 10 articles were selected for systematic review and seven entered the meta-analysis. Overall study quality was mediocre. Of the 2,694 patients initially treated for metastatic bone pain, 527 (20%) patients underwent reirradiation. Overall, a pain response after reirradiation was achieved in 58% of patients (pooled overall response rate 0.58, 95% confidence interval = 0.49–0.67). There was a substantial between-study heterogeneity (I 2 = 63.3%, p = 0.01) because of clinical and methodological differences between studies. Conclusions: Reirradiation of painful bone metastases is effective in terms of pain relief for a small majority of patients; approximately 40% of patients do not benefit from reirradiation. Although the validity of results is limited, this meta-analysis provides a comprehensive overview and the most quantitative estimate of reirradiation effectiveness to date.

  14. Quality of Caregiving in Mothers With Illicit Substance Use: A Systematic Review and Meta-analysis

    Directory of Open Access Journals (Sweden)

    Denise Hatzis

    2017-03-01

    Full Text Available Background: The quality of caregiving in mothers with substance abuse problems appears to be compromised. However, divergent findings, methodological variability, and sample characteristics point to the need for research synthesis. Methods: A comprehensive systematic search was undertaken. Studies were eligible if they (1 compared substance-misusing mothers with non–substance-misusing mothers, (2 involved children from birth to 3 years, and (3 maternal sensitivity and child responsiveness were measured using observational methodology. Results: A global meta-analysis for maternal sensitivity (n = 24 studies and child responsiveness (n = 16 studies on 3433 mother-infant dyads yielded significant population effect sizes and significant heterogeneity. Subgroup analyses found reduced heterogeneity when the meta-analysis was conducted on studies where groups were matched on key demographic characteristics; although the effect size was small, it was still significant for maternal sensitivity but not child responsiveness. Conclusions: Compromised quality of caregiving is found in high-risk, substance-misusing mothers, emphasising the importance of early intervention that draws from attachment-based interventions.

  15. Diagnostic accuracy of dual-energy computed tomography in patients with gout: A meta-analysis.

    Science.gov (United States)

    Lee, Young Ho; Song, Gwan Gyu

    2017-08-01

    This study aimed to evaluate the diagnostic performance of dual-energy computed tomography (DECT) for patients with gout. We searched the Medline, Embase, and Cochrane Library databases, and performed a meta-analysis on the diagnostic accuracy of DECT in patients with gout. A total of eight studies including 510 patients with gout and 268 controls (patients with non-gout inflammatory arthritis) were available for the meta-analysis. The pooled sensitivity and specificity of DECT were 84.7% (95% confidence interval [CI]: 81.3-87.7) and 93.7% (93.0-96.3), respectively. The positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 9.882 (6.122-15.95), 0.163 (0.097-0.272), and 78.10 (31.14-195.84), respectively. The area under the curve of DECT was 0.956 and the Q * index was 0.889, indicating a high diagnostic accuracy. Some between-study heterogeneity was found in the meta-analyses. However, there was no evidence of a threshold effect (Spearman correlation coefficient = 0.419; p = 0.035). In addition, meta-regression showed that the sample size, study design, and diagnostic criteria were not sources of heterogeneity, and subgroup meta-analyses did not change the overall diagnostic accuracy. Our meta-analysis of published studies demonstrates that DECT has a high diagnostic accuracy and plays an important role in the diagnosis of gout. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Siblings of children with a chronic illness: a meta-analysis.

    Science.gov (United States)

    Sharpe, Donald; Rossiter, Lucille

    2002-12-01

    To review the literature pertaining to the siblings of children with a chronic illness. Fifty-one published studies and 103 effect sizes were identified and examined through meta-analysis. We found (1) a modest, negative effect size statistic existed for siblings of children with a chronic illness relative to comparison participants or normative data; (2) heterogeneity existed for those effect sizes; (3) parent reports were more negative than child self-reports; (4) psychological functioning (i.e., depression, anxiety), peer activities, and cognitive development scores were lower for siblings of children with a chronic illness compared to controls; and (5) a cluster of chronic illnesses with daily treatment regimes was associated with negative effect statistics compared to chronic illnesses that did not affect daily functioning. More methodologically sound studies investigating the psychological functioning of siblings of children with a chronic illness are needed. Clinicians need to know that siblings of children with a chronic illness are at risk for negative psychological effects. Intervention programs for the siblings and families of children with a chronic illness should be developed.

  17. Alcohol and the risk of sleep apnoea: a systematic review and meta-analysis.

    Science.gov (United States)

    Simou, Evangelia; Britton, John; Leonardi-Bee, Jo

    2018-02-01

    A systematic review and meta-analysis of the association between alcohol consumption and risk of sleep apnoea in adults. We searched Medline, EMBASE and Web of Science databases from 1985 to 2015 for comparative epidemiological studies assessing the relation between alcohol consumption and sleep apnoea. Two authors independently screened and extracted data. Random effects meta-analysis was used to estimate pooled effect sizes with 95% confidence intervals (CI). Heterogeneity was quantified using I 2 and explored using subgroup analyses based on study exposure and outcome measures, quality, design, adjustment for confounders and geographical location. Publication bias was assessed using a funnel plot and Egger's test. We identified 21 studies from which estimates of relative risk could be obtained. Meta-analysis of these estimates demonstrated that higher levels of alcohol consumption increased the risk of sleep apnoea by 25% (RR 1.25, 95%CI 1.13-1.38, I 2  = 82%, p Country locations. We detected evidence of publication bias (p = 0.001). A further eight included studies reported average alcohol consumption in people with and without sleep apnoea. Meta-analysis revealed that mean alcohol intake was two units/week higher in those with sleep apnoea, but this difference was not statistically significant (p = 0.41). These findings suggest that alcohol consumption is associated with a higher risk of sleep apnoea, further supporting evidence that reducing alcohol intake is of potential therapeutic and preventive value in this condition. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Effectiveness of medical treatment for Cushing's syndrome: a systematic review and meta-analysis.

    Science.gov (United States)

    Broersen, Leonie H A; Jha, Meghna; Biermasz, Nienke R; Pereira, Alberto M; Dekkers, Olaf M

    2018-05-31

    To systematically review the effectiveness of medical treatment for Cushing's syndrome in clinical practice, regarding cortisol secretion, clinical symptom improvement, and quality of life. To assess the occurrence of side effects of these medical therapies. Eight electronic databases were searched in March 2017 to identify potentially relevant articles. Randomized controlled trials and cohort studies assessing the effectiveness of medical treatment in patients with Cushing's syndrome, were eligible. Pooled proportions were reported including 95% confidence intervals. We included 35 articles with in total 1520 patients in this meta-analysis. Most included patients had Cushing's disease. Pooled reported percentage of patients with normalization of cortisol ranged from 35.7% for cabergoline to 81.8% for mitotane in Cushing's disease. Patients using medication monotherapy showed a lower percentage of cortisol normalization compared to use of multiple medical agents (49.4 vs. 65.7%); this was even higher for patients with concurrent or previous radiotherapy (83.6%). Mild side effects were reported in 39.9%, and severe side effects were seen in 15.2% of patients after medical treatment. No meta-analyses were performed for clinical symptom improvement or quality of life due to lack of sufficient data. This meta-analysis shows that medication induces cortisol normalization effectively in a large percentage of patients. Medical treatment for Cushing's disease patients is thus a reasonable option in case of a contraindication for surgery, a recurrence, or in patients choosing not to have surgery. When experiencing side effects or no treatment effect, an alternate medical therapy or combination therapy can be considered.

  19. The effects of an edgeline on speed and lateral position: a meta-analysis

    NARCIS (Netherlands)

    van Driel, Cornelie J.G.; Davidse, Ragnhild J.; van Maarseveen, Martin F.A.M.

    2004-01-01

    This paper presents a meta-analysis of studies that have evaluated the effects of an edgeline on speed and lateral position of motorised road users. Together with many other study characteristics, 41 estimates of the effects of an edgeline on speed and 65 on lateral position were extracted from the

  20. Interventions in Higher Education and Their Effect on Student Success: A Meta-Analysis

    Science.gov (United States)

    Sneyers, Eline; De Witte, Kristof

    2018-01-01

    This article provides a meta-analysis on the effect of academic probation, student-faculty mentoring and need-based grants on various student outcomes. Using 25 (quasi-) experimental studies, we find that academic probation has a significant negative effect on retention (d = -0.17), while it does not have an effect on graduation. Student-faculty…

  1. Psychopathology in children with epilepsy: a meta-analysis

    NARCIS (Netherlands)

    Rodenburg, R.; Stams, G.J.; Meijer, A.M.; Aldenkamp, A.P.; Dekovic, M.

    2005-01-01

    Objective To examine the types and severity of psychopathology in children with epilepsy. Methods A series of meta-analyses were conducted to review 46 studies, including 2,434 children with epilepsy. Results Effect sizes were medium to large for comparisons with children from the general

  2. New trends in gender and mathematics performance: a meta-analysis.

    Science.gov (United States)

    Lindberg, Sara M; Hyde, Janet Shibley; Petersen, Jennifer L; Linn, Marcia C

    2010-11-01

    In this article, we use meta-analysis to analyze gender differences in recent studies of mathematics performance. First, we meta-analyzed data from 242 studies published between 1990 and 2007, representing the testing of 1,286,350 people. Overall, d = 0.05, indicating no gender difference, and variance ratio = 1.08, indicating nearly equal male and female variances. Second, we analyzed data from large data sets based on probability sampling of U.S. adolescents over the past 20 years: the National Longitudinal Surveys of Youth, the National Education Longitudinal Study of 1988, the Longitudinal Study of American Youth, and the National Assessment of Educational Progress. Effect sizes for the gender difference ranged between -0.15 and +0.22. Variance ratios ranged from 0.88 to 1.34. Taken together, these findings support the view that males and females perform similarly in mathematics.

  3. Effect of ethnicity on HbA1c levels in individuals without diabetes: Systematic review and meta-analysis

    Science.gov (United States)

    Freitas, Priscila Aparecida Correa; Gross, Jorge Luiz

    2017-01-01

    Aims/Hypothesis Disparities in HbA1c levels have been observed among ethnic groups. Most studies were performed in patients with diabetes mellitus (DM), which may interfere with results due to the high variability of glucose levels. We conducted a systematic review and meta-analysis to investigate the effect of ethnicity on HbA1c levels in individuals without DM. Methods This is a systematic review with meta-analysis. We searched MEDLINE and EMBASE up to September 2016. Studies published after 1996, performed in adults without DM, reporting HbA1c results measured by certified/standardized methods were included. A random effects model was used and the effect size was presented as weighted HbA1c mean difference (95% CI) between different ethnicities as compared to White ethnicity. Results Twelve studies met the inclusion criteria, totalling data from 49,238 individuals. There were significant differences between HbA1c levels in Blacks [0.26% (2.8 mmol/mol); 95% CI 0.18 to 0.33 (2.0 to 3.6), p HbA1c values are higher in Blacks, Asians, and Latinos when compared to White persons. Although small, these differences might have impact on the use of a sole HbA1c point to diagnose DM in all ethnic populations. PMID:28192447

  4. MetaComp: comprehensive analysis software for comparative meta-omics including comparative metagenomics.

    Science.gov (United States)

    Zhai, Peng; Yang, Longshu; Guo, Xiao; Wang, Zhe; Guo, Jiangtao; Wang, Xiaoqi; Zhu, Huaiqiu

    2017-10-02

    During the past decade, the development of high throughput nucleic sequencing and mass spectrometry analysis techniques have enabled the characterization of microbial communities through metagenomics, metatranscriptomics, metaproteomics and metabolomics data. To reveal the diversity of microbial communities and interactions between living conditions and microbes, it is necessary to introduce comparative analysis based upon integration of all four types of data mentioned above. Comparative meta-omics, especially comparative metageomics, has been established as a routine process to highlight the significant differences in taxon composition and functional gene abundance among microbiota samples. Meanwhile, biologists are increasingly concerning about the correlations between meta-omics features and environmental factors, which may further decipher the adaptation strategy of a microbial community. We developed a graphical comprehensive analysis software named MetaComp comprising a series of statistical analysis approaches with visualized results for metagenomics and other meta-omics data comparison. This software is capable to read files generated by a variety of upstream programs. After data loading, analyses such as multivariate statistics, hypothesis testing of two-sample, multi-sample as well as two-group sample and a novel function-regression analysis of environmental factors are offered. Here, regression analysis regards meta-omic features as independent variable and environmental factors as dependent variables. Moreover, MetaComp is capable to automatically choose an appropriate two-group sample test based upon the traits of input abundance profiles. We further evaluate the performance of its choice, and exhibit applications for metagenomics, metaproteomics and metabolomics samples. MetaComp, an integrative software capable for applying to all meta-omics data, originally distills the influence of living environment on microbial community by regression analysis

  5. The relationship between nature connectedness and happiness: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Colin A. Capaldi

    2014-09-01

    Full Text Available Research suggests that contact with nature can be beneficial, for example leading to improvements in mood, cognition, and health. A distinct but related idea is the personality construct of subjective nature connectedness, a stable individual difference in cognitive, affective, and experiential connection with the natural environment. Subjective nature connectedness is a strong predictor of pro-environmental attitudes and behaviours that may also be positively associated with subjective well-being. This meta-analysis was conducted to examine the relationship between nature connectedness and happiness. Based on 30 samples (n = 8,523, a fixed-effect meta-analysis found a small but significant effect size (r = .19. Those who are more connected to nature tended to experience more positive affect, vitality, and life satisfaction compared to those less connected to nature. Publication status, year, average age, and percentage of females in the sample were not significant moderators. Vitality had the strongest relationship with nature connectedness (r = .24, followed by positive affect (r = .22 and life satisfaction (r = .17. In terms of specific nature connectedness measures, associations were the strongest between happiness and inclusion of nature in self (r = .27, compared to nature relatedness (r = .18 and connectedness to nature (r = .18. This research highlights the importance of considering personality when examining the psychological benefits of nature. The results suggest that closer human-nature relationships do not have to come at the expense of happiness. Rather, this meta-analysis shows that being connected to nature and feeling happy are, in fact, connected.

  6. The effect of funding sources on donepezil randomised controlled trial outcome: a meta-analysis.

    Science.gov (United States)

    Killin, Lewis O J; Russ, Tom C; Starr, John M; Abrahams, Sharon; Della Sala, Sergio

    2014-04-07

    To investigate whether there is a difference in the treatment effect of donepezil on cognition in Alzheimer disease between industry-funded and independent randomised controlled trials. Fixed effects meta-analysis of standardised effects of donepezil on cognition as measured by the Mini Mental State Examination and the Alzheimer's Disease Assessment Scale-cognitive subscale. Studies included in the meta-analyses reported in the National Institute for Health and Care Excellence (NICE) technical appraisal 217 updated with new studies through a PubMed search. Inclusion criteria were double-blind, placebo-controlled trials of any length comparing patients diagnosed with probable Alzheimer disease (according to the NINCDS-ADRDA/DSM-III/IV criteria) taking any dosage of donepezil. Studies of combination therapies (eg, donepezil and memantine) were excluded, as were studies that enrolled patients with a diagnosis of Alzheimer disease associated with other disorders (eg, Parkinson's disease and Down's syndrome). Our search strategy identified 14 relevant trials (4 independent) with suitable data. Trials sponsored by pharmaceutical companies reported a larger effect of donepezil on standardised cognitive tests than trials published by independent research groups (standardised mean difference (SMD)=0.46, 95% CI 0.37 to 0.55 vs SMD=0.33, 95% CI 0.18 to 0.48, respectively). This difference remained when only data representing change up to 12 weeks from baseline were analysed (industry SMD=0.44, 95% CI 0.34 to 0.53 vs independent SMD=0.35, 95% CI 0.18 to 0.52). Analysis revealed that the effect of funding as a moderator variable of study heterogeneity was not statistically significant at either time point. The effect size of donepezil on cognition is larger in industry-funded than independent trials and this is not explained by the longer duration of industry-funded trials. The lack of a statistically significant moderator effect may indicate that the differences are due to

  7. Systematic review with meta-analysis

    DEFF Research Database (Denmark)

    Kimer, N; Krag, A; Møller, Søren

    2014-01-01

    BACKGROUND: Rifaximin is recommended for prevention of hepatic encephalopathy (HE). The effects of rifaximin on overt and minimal HE are debated. AIM: To perform a systematic review and meta-analysis of randomised controlled trials (RCTs) on rifaximin for HE. METHODS: We performed electronic...... and manual searches, gathered information from the U.S. Food and Drug Administration Home Page, and obtained unpublished information on trial design and outcome measures from authors and pharmaceutical companies. Meta-analyses were performed and results presented as risk ratios (RR) with 95% confidence...

  8. A meta-analysis on the relationship between self-reported presence and anxiety in virtual reality exposure therapy for anxiety disorders.

    Directory of Open Access Journals (Sweden)

    Yun Ling

    Full Text Available In virtual reality exposure therapy (VRET for anxiety disorders, sense of presence in the virtual environment is considered the principal mechanism that enables anxiety to be felt. Existing studies on the relation between sense of presence and level of anxiety, however, have yielded mixed results on the correlation between the two. In this meta-analysis, we reviewed publications on VRET for anxiety that included self-reported presence and anxiety. The comprehensive search of the literature identified 33 publications with a total of 1196 participants. The correlation between self-reported sense of presence and anxiety was extracted and meta-analyzed. Potential moderators such as technology characteristics, sample characteristics including age, gender and clinical status, disorder characteristics and study design characteristics such as measurements were also examined. The random effects analysis showed a medium effect size for the correlation between sense of presence and anxiety (r = .28; 95% CI: 0.18-0.38. Moderation analyses revealed that the effect size of the correlation differed across different anxiety disorders, with a large effect size for fear of animals (r = .50; 95% CI: 0.30-0.66 and a no to small effect size for social anxiety disorder (r = .001; 95% CI: -0.19-0.19. Further, the correlation between anxiety and presence was stronger in studies with participants who met criteria for an anxiety disorder than in studies with a non-clinical population. Trackers with six degrees of freedom and displays with a larger field of view resulted in higher effect sizes, compared to trackers with three degrees of freedom and displays with a smaller field of view. In addition, no difference in effect size was found for the type of presence measurement and the type of anxiety measurement. This meta-analysis confirms the positive relation between sense of presence and anxiety and demonstrates that this relation can be affected by various moderating

  9. Characteristics of meta-analyses and their component studies in the Cochrane Database of Systematic Reviews: a cross-sectional, descriptive analysis

    Directory of Open Access Journals (Sweden)

    Davey Jonathan

    2011-11-01

    Full Text Available Abstract Background Cochrane systematic reviews collate and summarise studies of the effects of healthcare interventions. The characteristics of these reviews and the meta-analyses and individual studies they contain provide insights into the nature of healthcare research and important context for the development of relevant statistical and other methods. Methods We classified every meta-analysis with at least two studies in every review in the January 2008 issue of the Cochrane Database of Systematic Reviews (CDSR according to the medical specialty, the types of interventions being compared and the type of outcome. We provide descriptive statistics for numbers of meta-analyses, numbers of component studies and sample sizes of component studies, broken down by these categories. Results We included 2321 reviews containing 22,453 meta-analyses, which themselves consist of data from 112,600 individual studies (which may appear in more than one meta-analysis. Meta-analyses in the areas of gynaecology, pregnancy and childbirth (21%, mental health (13% and respiratory diseases (13% are well represented in the CDSR. Most meta-analyses address drugs, either with a control or placebo group (37% or in a comparison with another drug (25%. The median number of meta-analyses per review is six (inter-quartile range 3 to 12. The median number of studies included in the meta-analyses with at least two studies is three (inter-quartile range 2 to 6. Sample sizes of individual studies range from 2 to 1,242,071, with a median of 91 participants. Discussion It is clear that the numbers of studies eligible for meta-analyses are typically very small for all medical areas, outcomes and interventions covered by Cochrane reviews. This highlights the particular importance of suitable methods for the meta-analysis of small data sets. There was little variation in number of studies per meta-analysis across medical areas, across outcome data types or across types of

  10. Does chocolate reduce blood pressure? A meta-analysis

    Directory of Open Access Journals (Sweden)

    Ried Karin

    2010-06-01

    Full Text Available Abstract Background Dark chocolate and flavanol-rich cocoa products have attracted interest as an alternative treatment option for hypertension, a known risk factor for cardiovascular disease. Previous meta-analyses concluded that cocoa-rich foods may reduce blood pressure. Recently, several additional trials have been conducted with conflicting results. Our study summarises current evidence on the effect of flavanol-rich cocoa products on blood pressure in hypertensive and normotensive individuals. Methods We searched Medline, Cochrane and international trial registries between 1955 and 2009 for randomised controlled trials investigating the effect of cocoa as food or drink compared with placebo on systolic and diastolic blood pressure (SBP/DBP for a minimum duration of 2 weeks. We conducted random effects meta-analysis of all studies fitting the inclusion criteria, as well as subgroup analysis by baseline blood pressure (hypertensive/normotensive. Meta-regression analysis explored the association between type of treatment, dosage, duration or baseline blood pressure and blood pressure outcome. Statistical significance was set at P Results Fifteen trial arms of 13 assessed studies met the inclusion criteria. Pooled meta-analysis of all trials revealed a significant blood pressure-reducing effect of cocoa-chocolate compared with control (mean BP change ± SE: SBP: -3.2 ± 1.9 mmHg, P = 0.001; DBP: -2.0 ± 1.3 mmHg, P = 0.003. However, subgroup meta-analysis was significant only for the hypertensive or prehypertensive subgroups (SBP: -5.0 ± 3.0 mmHg; P = 0.0009; DBP: -2.7 ± 2.2 mm Hg, P = 0.01, while BP was not significantly reduced in the normotensive subgroups (SBP: -1.6 ± 2.3 mmHg, P = 0.17; DBP: -1.3 ± 1.6 mmHg, P = 0.12. Nine trials used chocolate containing 50% to 70% cocoa compared with white chocolate or other cocoa-free controls, while six trials compared high- with low-flavanol cocoa products. Daily flavanol dosages ranged from 30

  11. Dose-Dependent Effects of Statins for Patients with Aneurysmal Subarachnoid Hemorrhage: Meta-Regression Analysis.

    Science.gov (United States)

    To, Minh-Son; Prakash, Shivesh; Poonnoose, Santosh I; Bihari, Shailesh

    2018-05-01

    The study uses meta-regression analysis to quantify the dose-dependent effects of statin pharmacotherapy on vasospasm, delayed ischemic neurologic deficits (DIND), and mortality in aneurysmal subarachnoid hemorrhage. Prospective, retrospective observational studies, and randomized controlled trials (RCTs) were retrieved by a systematic database search. Summary estimates were expressed as absolute risk (AR) for a given statin dose or control (placebo). Meta-regression using inverse variance weighting and robust variance estimation was performed to assess the effect of statin dose on transformed AR in a random effects model. Dose-dependence of predicted AR with 95% confidence interval (CI) was recovered by using Miller's Freeman-Tukey inverse. The database search and study selection criteria yielded 18 studies (2594 patients) for analysis. These included 12 RCTs, 4 retrospective observational studies, and 2 prospective observational studies. Twelve studies investigated simvastatin, whereas the remaining studies investigated atorvastatin, pravastatin, or pitavastatin, with simvastatin-equivalent doses ranging from 20 to 80 mg. Meta-regression revealed dose-dependent reductions in Freeman-Tukey-transformed AR of vasospasm (slope coefficient -0.00404, 95% CI -0.00720 to -0.00087; P = 0.0321), DIND (slope coefficient -0.00316, 95% CI -0.00586 to -0.00047; P = 0.0392), and mortality (slope coefficient -0.00345, 95% CI -0.00623 to -0.00067; P = 0.0352). The present meta-regression provides weak evidence for dose-dependent reductions in vasospasm, DIND and mortality associated with acute statin use after aneurysmal subarachnoid hemorrhage. However, the analysis was limited by substantial heterogeneity among individual studies. Greater dosing strategies are a potential consideration for future RCTs. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Automatic imitation: A meta-analysis.

    Science.gov (United States)

    Cracco, Emiel; Bardi, Lara; Desmet, Charlotte; Genschow, Oliver; Rigoni, Davide; De Coster, Lize; Radkova, Ina; Deschrijver, Eliane; Brass, Marcel

    2018-05-01

    Automatic imitation is the finding that movement execution is facilitated by compatible and impeded by incompatible observed movements. In the past 15 years, automatic imitation has been studied to understand the relation between perception and action in social interaction. Although research on this topic started in cognitive science, interest quickly spread to related disciplines such as social psychology, clinical psychology, and neuroscience. However, important theoretical questions have remained unanswered. Therefore, in the present meta-analysis, we evaluated seven key questions on automatic imitation. The results, based on 161 studies containing 226 experiments, revealed an overall effect size of g z = 0.95, 95% CI [0.88, 1.02]. Moderator analyses identified automatic imitation as a flexible, largely automatic process that is driven by movement and effector compatibility, but is also influenced by spatial compatibility. Automatic imitation was found to be stronger for forced choice tasks than for simple response tasks, for human agents than for nonhuman agents, and for goalless actions than for goal-directed actions. However, it was not modulated by more subtle factors such as animacy beliefs, motion profiles, or visual perspective. Finally, there was no evidence for a relation between automatic imitation and either empathy or autism. Among other things, these findings point toward actor-imitator similarity as a crucial modulator of automatic imitation and challenge the view that imitative tendencies are an indicator of social functioning. The current meta-analysis has important theoretical implications and sheds light on longstanding controversies in the literature on automatic imitation and related domains. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  13. Brain vs behavior: an effect size comparison of neuroimaging and cognitive studies of genetic risk for schizophrenia.

    LENUS (Irish Health Repository)

    Rose, Emma Jane

    2013-05-01

    Genetic variants associated with increased risk for schizophrenia (SZ) are hypothesized to be more penetrant at the level of brain structure and function than at the level of behavior. However, to date the relative sensitivity of imaging vs cognitive measures of these variants has not been quantified. We considered effect sizes associated with cognitive and imaging studies of 9 robust SZ risk genes (DAOA, DISC1, DTNBP1, NRG1, RGS4, NRGN, CACNA1C, TCF4, and ZNF804A) published between January 2005-November 2011. Summary data was used to calculate estimates of effect size for each significant finding. The mean effect size for each study was categorized as small, medium, or large and the relative frequency of each category was compared between modalities and across genes. Random effects meta-analysis was used to consider the impact of experimental methodology on effect size. Imaging studies reported mostly medium or large effects, whereas cognitive investigations commonly reported small effects. Meta-analysis confirmed that imaging studies were associated with larger effects. Effect size estimates were negatively correlated with sample size but did not differ as a function of gene nor imaging modality. These observations support the notion that SZ risk variants show larger effects, and hence greater penetrance, when characterized using indices of brain structure and function than when indexed by cognitive measures. However, it remains to be established whether this holds true for individual risk variants, imaging modalities, or cognitive functions, and how such effects may be mediated by a relationship with sample size and other aspects of experimental variability.

  14. Comparative efficacy of seven psychotherapeutic interventions for patients with depression: a network meta-analysis.

    Directory of Open Access Journals (Sweden)

    Jürgen Barth

    Full Text Available BACKGROUND: Previous meta-analyses comparing the efficacy of psychotherapeutic interventions for depression were clouded by a limited number of within-study treatment comparisons. This study used network meta-analysis, a novel methodological approach that integrates direct and indirect evidence from randomised controlled studies, to re-examine the comparative efficacy of seven psychotherapeutic interventions for adult depression. METHODS AND FINDINGS: We conducted systematic literature searches in PubMed, PsycINFO, and Embase up to November 2012, and identified additional studies through earlier meta-analyses and the references of included studies. We identified 198 studies, including 15,118 adult patients with depression, and coded moderator variables. Each of the seven psychotherapeutic interventions was superior to a waitlist control condition with moderate to large effects (range d = -0.62 to d = -0.92. Relative effects of different psychotherapeutic interventions on depressive symptoms were absent to small (range d = 0.01 to d = -0.30. Interpersonal therapy was significantly more effective than supportive therapy (d = -0.30, 95% credibility interval [CrI] [-0.54 to -0.05]. Moderator analysis showed that patient characteristics had no influence on treatment effects, but identified aspects of study quality and sample size as effect modifiers. Smaller effects were found in studies of at least moderate (Δd = 0.29 [-0.01 to 0.58]; p = 0.063 and large size (Δd = 0.33 [0.08 to 0.61]; p = 0.012 and those that had adequate outcome assessment (Δd = 0.38 [-0.06 to 0.87]; p = 0.100. Stepwise restriction of analyses by sample size showed robust effects for cognitive-behavioural therapy, interpersonal therapy, and problem-solving therapy (all d>0.46 compared to waitlist. Empirical evidence from large studies was unavailable or limited for other psychotherapeutic interventions. CONCLUSIONS: Overall our

  15. Effect of metformin treatment during pregnancy on women with PCOS: a systematic review and meta-analysis.

    Science.gov (United States)

    Tan, Xingrong; Li, Shengbing; Chang, Ying; Fang, Chao; Liu, Hua; Zhang, Xingping; Wang, Yi

    2016-09-11

    Some previous studies have found that continued metformin use is beneficial in the management of polycystic ovary syndrome (PCOS) in pregnant women. A systemic review and meta-analysis were needed to more fully assess the effects of metformin on pregnant PCOS patients. The literature was fully searched using MEDLINE, EMBASE, SCOPUS, and COCHRANE for continued metformin use during pregnancy in women with PCOS. A systematic review and meta-analysis were performed to evaluate the comprehensive effects of continued metformin treatment on pregnancy-related outcomes in these women. Eleven eligible studies out of 127 relevant publications were included in meta-analysis. The rates of early pregnancy loss and preterm delivery were found to be significantly decreased in metformin-treated PCOS women. A non-significant difference was found in fetal abnormality and fetal birth weight between the metformin-treated and the non-treated groups. The incidence of gestational diabetes mellitus (GDM) and hypertension/preeclampsia were not significantly different in the two groups, probably because of inconsistent results in the subgroup analysis. Our results showed that continued use during of metformin, during pregnancy in women with PCOS, had no effect on incidence of fetal abnormalities or fetal birth weight. The effects of metformin on GDM and hypertension/preeclampsia should be determined through high-quality randomized controlled trials.

  16. The Effect of Campaign-Generated Interpersonal Communication on Campaign-Targeted Health Outcomes: A Meta-Analysis.

    Science.gov (United States)

    Jeong, Michelle; Bae, Rosie Eungyuhl

    2017-06-16

    This study examined the effect of mass media campaign-generated conversations on campaign-targeted health outcomes, via a systematic meta-analysis of 28 studies (including 124 sub-studies and a total of 138,898 participants). The study also conducted a series of moderation analyses to examine the conditions under which interpersonal communication has larger effects on bringing about the desired outcomes. The findings of this meta-analysis indicate that campaign-generated conversations have a positive effect on inducing campaign-targeted outcomes (OR = 1.28) and show that this effect is moderated by health topic addressed by the campaign, the type of outcome being targeted by the campaign, and with whom people converse, along with several other campaign-relevant and study-relevant variables. The implications of these findings for future research are discussed.

  17. Meta-Analysis of Placental Transcriptome Data Identifies a Novel Molecular Pathway Related to Preeclampsia.

    Directory of Open Access Journals (Sweden)

    Miranda van Uitert

    Full Text Available Studies using the placental transcriptome to identify key molecules relevant for preeclampsia are hampered by a relatively small sample size. In addition, they use a variety of bioinformatics and statistical methods, making comparison of findings challenging. To generate a more robust preeclampsia gene expression signature, we performed a meta-analysis on the original data of 11 placenta RNA microarray experiments, representing 139 normotensive and 116 preeclamptic pregnancies. Microarray data were pre-processed and analyzed using standardized bioinformatics and statistical procedures and the effect sizes were combined using an inverse-variance random-effects model. Interactions between genes in the resulting gene expression signature were identified by pathway analysis (Ingenuity Pathway Analysis, Gene Set Enrichment Analysis, Graphite and protein-protein associations (STRING. This approach has resulted in a comprehensive list of differentially expressed genes that led to a 388-gene meta-signature of preeclamptic placenta. Pathway analysis highlights the involvement of the previously identified hypoxia/HIF1A pathway in the establishment of the preeclamptic gene expression profile, while analysis of protein interaction networks indicates CREBBP/EP300 as a novel element central to the preeclamptic placental transcriptome. In addition, there is an apparent high incidence of preeclampsia in women carrying a child with a mutation in CREBBP/EP300 (Rubinstein-Taybi Syndrome. The 388-gene preeclampsia meta-signature offers a vital starting point for further studies into the relevance of these genes (in particular CREBBP/EP300 and their concomitant pathways as biomarkers or functional molecules in preeclampsia. This will result in a better understanding of the molecular basis of this disease and opens up the opportunity to develop rational therapies targeting the placental dysfunction causal to preeclampsia.

  18. Effect of psychiatric consultation models in primary care. A systematic review and meta-analysis of randomized clinical trials.

    Science.gov (United States)

    van der Feltz-Cornelis, Christina M; Van Os, Titus W D P; Van Marwijk, Harm W J; Leentjens, Albert F G

    2010-06-01

    Psychiatric consultation in primary care is meant to enhance and improve treatment for mental disorder in that setting. An estimate of the effect for different conditions as well as identification of particularly effective elements is needed. Database search for randomized controlled trials (RCTs) on psychiatric consultation in primary care. Validity assessment and data extraction according to Cochrane criteria were performed by independent assessors in duplicate. Meta-analysis was performed. Data were collected from 10 RCTs with a total of 3408 included patients with somatoform disorder or depressive disorder, which compared psychiatric consultation to care as usual (CAU). Meta-analysis irrespective of condition showed a weighted mean indicating a combined assessment of illness burden as outcome of psychiatric consultation, compared to CAU, of 0.313 (95% CI 0.190-0.437). The effect was especially large in somatoform disorder (0.614; 95% CI 0.206-1.022). RCTs in which after the consult, consultation advice was given by means of a consultation letter, showed a combined weighted mean effect size of 0.561 (95% CI 0.337-0.786), while studies not using such a letter showed a small effect of 0.210 (95% CI 0.102-0.319). Effects are highest on utilization of health care services with 0.507 (95% CI 0.305-0.708). Psychiatric consultation in the primary care setting is effective in patients with somatoform and depressive disorder. Largest effects are seen in reduction of utilization of health care services. Copyright 2010 Elsevier Inc. All rights reserved.

  19. Effects of pharmacological concentrations of dietary zinc oxide on growth of post-weaning pigs: a meta-analysis.

    Science.gov (United States)

    Sales, James

    2013-06-01

    Pharmacological dietary zinc (Zn) concentrations of 1,000 to 3,000 mg/kg diet from Zn oxide have been found to increase growth in post-weaning pigs. However, results were inconsistent among studies. A frequentist meta-analysis, in which effects were numerically described with standardized effect sizes (Hedges's g), was conducted in order to identify and quantify the responses in average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G/F) in post-weaning pigs upon dietary Zn supplementation from Zn oxide. The inability of independent continuous variables to explain significant heterogeneity obtained with fixed effect models necessitated the use of random effects models to calculate summary statistics. Dietary Zn supplementation increased (P potential environmental pollution will have to be negated by alternative feed additives and management strategies in order to prevent economic losses.

  20. Predictors of persistent pain after total knee arthroplasty: a systematic review and meta-analysis.

    Science.gov (United States)

    Lewis, G N; Rice, D A; McNair, P J; Kluger, M

    2015-04-01

    Several studies have identified clinical, psychosocial, patient characteristic, and perioperative variables that are associated with persistent postsurgical pain; however, the relative effect of these variables has yet to be quantified. The aim of the study was to provide a systematic review and meta-analysis of predictor variables associated with persistent pain after total knee arthroplasty (TKA). Included studies were required to measure predictor variables prior to or at the time of surgery, include a pain outcome measure at least 3 months post-TKA, and include a statistical analysis of the effect of the predictor variable(s) on the outcome measure. Counts were undertaken of the number of times each predictor was analysed and the number of times it was found to have a significant relationship with persistent pain. Separate meta-analyses were performed to determine the effect size of each predictor on persistent pain. Outcomes from studies implementing uni- and multivariable statistical models were analysed separately. Thirty-two studies involving almost 30 000 patients were included in the review. Preoperative pain was the predictor that most commonly demonstrated a significant relationship with persistent pain across uni- and multivariable analyses. In the meta-analyses of data from univariate models, the largest effect sizes were found for: other pain sites, catastrophizing, and depression. For data from multivariate models, significant effects were evident for: catastrophizing, preoperative pain, mental health, and comorbidities. Catastrophizing, mental health, preoperative knee pain, and pain at other sites are the strongest independent predictors of persistent pain after TKA. © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Plasma L-tryptophan concentration in major depressive disorder: new data and meta-analysis.

    Science.gov (United States)

    Ogawa, Shintaro; Fujii, Takashi; Koga, Norie; Hori, Hiroaki; Teraishi, Toshiya; Hattori, Kotaro; Noda, Takamasa; Higuchi, Teruhiko; Motohashi, Nobutaka; Kunugi, Hiroshi

    2014-09-01

    Tryptophan, an essential amino acid, is the precursor to serotonin and is metabolized mainly by the kynurenine pathway. Both serotonin and kynurenine have been implicated in the pathophysiology of major depressive disorder (MDD). However, plasma tryptophan concentration in patients with MDD has not unequivocally been reported to be decreased, which prompted us to perform a meta-analysis on previous studies and our own data. We searched the PubMed database for case-control studies published until August 31, 2013, using the search terms plasma AND tryptophan AND synonyms for MDD. An additional search was performed for the term amino acid instead of tryptophan. We obtained our own data in 66 patients with MDD (DSM-IV) and 82 controls who were recruited from March 2011 to July 2012. The majority of the patients were medicated (N = 53). Total plasma tryptophan concentrations were measured by the liquid chromatography/mass spectrometry method. We scrutinized 160 studies for eligibility. Original articles that were written in English and documented plasma tryptophan values in patients and controls were selected. We included 24 studies from the literature and our own data in the meta-analysis, which involved a total of 744 patients and 793 controls. Data on unmedicated patients (N = 156) and their comparison subjects (N = 203) were also extracted. To see the possible correlation between tryptophan concentrations and depression severity, meta-regression analysis was performed for 10 studies with the Hamilton Depression Rating Scale 17-item version score. In our case-control study, mean (SD) plasma tryptophan level was significantly decreased in the MDD patients versus the controls (53.9 [10.9] vs 57.2 [11.3] μmol/L; P = .03). The meta-analysis after adjusting for publication bias showed a significant decrease in patients with MDD with a modest effect size (Hedges g, -0.45). However, analysis on unmedicated subjects yielded a large effect (Hedges g, -0.84; P = .00015). We

  2. Deviation from intention to treat analysis in randomised trials and treatment effect estimates: meta-epidemiological study.

    Science.gov (United States)

    Abraha, Iosief; Cherubini, Antonio; Cozzolino, Francesco; De Florio, Rita; Luchetta, Maria Laura; Rimland, Joseph M; Folletti, Ilenia; Marchesi, Mauro; Germani, Antonella; Orso, Massimiliano; Eusebi, Paolo; Montedori, Alessandro

    2015-05-27

    To examine whether deviation from the standard intention to treat analysis has an influence on treatment effect estimates of randomised trials. Meta-epidemiological study. Medline, via PubMed, searched between 2006 and 2010; 43 systematic reviews of interventions and 310 randomised trials were included. From each year searched, random selection of 5% of intervention reviews with a meta-analysis that included at least one trial that deviated from the standard intention to treat approach. Basic characteristics of the systematic reviews and randomised trials were extracted. Information on the reporting of intention to treat analysis, outcome data, risk of bias items, post-randomisation exclusions, and funding were extracted from each trial. Trials were classified as: ITT (reporting the standard intention to treat approach), mITT (reporting a deviation from the standard approach), and no ITT (reporting no approach). Within each meta-analysis, treatment effects were compared between mITT and ITT trials, and between mITT and no ITT trials. The ratio of odds ratios was calculated (value deviated from the intention to treat analysis showed larger intervention effects than trials that reported the standard approach. Where an intention to treat analysis is impossible to perform, authors should clearly report who is included in the analysis and attempt to perform multiple imputations. © Abraha et al 2015.

  3. Racism and health service utilisation: A systematic review and meta-analysis

    Science.gov (United States)

    Cormack, Donna; Harris, Ricci; Paradies, Yin

    2017-01-01

    Although racism has been posited as driver of racial/ethnic inequities in healthcare, the relationship between racism and health service use and experience has yet to be systematically reviewed or meta-analysed. This paper presents a systematic review and meta-analysis of quantitative empirical studies that report associations between self-reported racism and various measures of healthcare service utilisation. Data were reviewed and extracted from 83 papers reporting 70 studies. Studies included 250,850 participants and were conducted predominately in the U.S. The meta-analysis included 59 papers reporting 52 studies, which were analysed using random effects models and mean weighted effect sizes. Racism was associated with more negative patient experiences of health services (HSU-E) (OR = 0.351 (95% CI [0.236,0.521], k = 19), including lower levels of healthcare-related trust, satisfaction, and communication. Racism was not associated with health service use (HSU-U) as an outcome group, and was not associated with most individual HSU-U outcomes, including having had examinations, health service visits and admissions to health professionals and services. Racism was associated with health service use outcomes such as delaying/not getting healthcare, and lack of adherence to treatment uptake, although these effects may be influenced by a small sample of studies, and publication bias, respectively. Limitations to the literature reviewed in terms of study designs, sampling methods and measurements are discussed along with suggested future directions in the field. PMID:29253855

  4. Racism and health service utilisation: A systematic review and meta-analysis.

    Science.gov (United States)

    Ben, Jehonathan; Cormack, Donna; Harris, Ricci; Paradies, Yin

    2017-01-01

    Although racism has been posited as driver of racial/ethnic inequities in healthcare, the relationship between racism and health service use and experience has yet to be systematically reviewed or meta-analysed. This paper presents a systematic review and meta-analysis of quantitative empirical studies that report associations between self-reported racism and various measures of healthcare service utilisation. Data were reviewed and extracted from 83 papers reporting 70 studies. Studies included 250,850 participants and were conducted predominately in the U.S. The meta-analysis included 59 papers reporting 52 studies, which were analysed using random effects models and mean weighted effect sizes. Racism was associated with more negative patient experiences of health services (HSU-E) (OR = 0.351 (95% CI [0.236,0.521], k = 19), including lower levels of healthcare-related trust, satisfaction, and communication. Racism was not associated with health service use (HSU-U) as an outcome group, and was not associated with most individual HSU-U outcomes, including having had examinations, health service visits and admissions to health professionals and services. Racism was associated with health service use outcomes such as delaying/not getting healthcare, and lack of adherence to treatment uptake, although these effects may be influenced by a small sample of studies, and publication bias, respectively. Limitations to the literature reviewed in terms of study designs, sampling methods and measurements are discussed along with suggested future directions in the field.

  5. Updated Meta-Analysis of Learner Control within Educational Technology

    Science.gov (United States)

    Karich, Abbey C.; Burns, Matthew K.; Maki, Kathrin E.

    2014-01-01

    Giving a student control over their learning has theoretical and intuitive appeal, but its effects are neither powerful nor consistent in the empirical literature base. This meta-analysis updated previous meta-analytic research by Niemiec, Sikorski, and Walberg by studying the overall effectiveness of providing learner control within educational…

  6. Caffeine ingestion enhances Wingate performance: a meta-analysis.

    Science.gov (United States)

    Grgic, Jozo

    2018-03-01

    The positive effects of caffeine ingestion on aerobic performance are well-established; however, recent findings are suggesting that caffeine ingestion might also enhance components of anaerobic performance. A commonly used test of anaerobic performance and power output is the 30-second Wingate test. Several studies explored the effects of caffeine ingestion on Wingate performance, with equivocal findings. To elucidate this topic, this paper aims to determine the effects of caffeine ingestion on Wingate performance using meta-analytic statistical techniques. Following a search through PubMed/MEDLINE, Scopus, and SportDiscus ® , 16 studies were found meeting the inclusion criteria (pooled number of participants = 246). Random-effects meta-analysis of standardized mean differences (SMD) for peak power output and mean power output was performed. Study quality was assessed using the modified version of the PEDro checklist. Results of the meta-analysis indicated a significant difference (p = .005) between the placebo and caffeine trials on mean power output with SMD values of small magnitude (0.18; 95% confidence interval: 0.05, 0.31; +3%). The meta-analysis performed for peak power output indicated a significant difference (p = .006) between the placebo and caffeine trials (SMD = 0.27; 95% confidence interval: 0.08, 0.47 [moderate magnitude]; +4%). The results from the PEDro checklist indicated that, in general, studies are of good and excellent methodological quality. This meta-analysis adds on to the current body of evidence showing that caffeine ingestion can also enhance components of anaerobic performance. The results presented herein may be helpful for developing more efficient evidence-based recommendations regarding caffeine supplementation.

  7. Immediate effects of alcohol marketing communications and media portrayals on consumption and cognition: a systematic review and meta-analysis of experimental studies.

    Science.gov (United States)

    Stautz, Kaidy; Brown, Kyle G; King, Sarah E; Shemilt, Ian; Marteau, Theresa M

    2016-06-09

    Restricting marketing of alcoholic products is purported to be a cost-effective intervention to reduce alcohol consumption. The strength of evidence supporting this claim is contested. This systematic review aimed to assess immediate effects of exposure to alcohol marketing on alcoholic beverage consumption and related cognitions. Electronic searches of nine databases, supplemented with reference list searches and forward citation tracking, were used to identify randomised, experimental studies assessing immediate effects of exposure to alcohol marketing communications on objective alcohol consumption (primary outcome), explicit or implicit alcohol-related cognitions, or selection without purchasing (secondary outcomes). Study limitations were assessed using the Cochrane Risk of Bias tool. Random and fixed effects meta-analyses were conducted to estimate effect sizes. Twenty four studies met the eligibility criteria. A meta-analysis integrating seven studies (758 participants, all students) found that viewing alcohol advertisements increased immediate alcohol consumption relative to viewing non-alcohol advertisements (SMD = 0.20, 95 % CI = 0.05, 0.34). A meta-analysis integrating six studies (631 participants, all students) did not find that viewing alcohol portrayals in television programmes or films increased consumption (SMD = 0.16, 95 % CI = -0.05, 0.37). Meta-analyses of secondary outcome data found that exposure to alcohol portrayals increased explicit alcohol-related cognitions, but did not find that exposure to alcohol advertisements influenced explicit or implicit alcohol-related cognitions. Confidence in results is diminished by underpowered analyses and unclear risk of bias. Viewing alcohol advertisements (but not alcohol portrayals) may increase immediate alcohol consumption by small amounts, equivalent to between 0.39 and 2.67 alcohol units for males and between 0.25 and 1.69 units for females. The generalizability of this finding

  8. Immediate effects of alcohol marketing communications and media portrayals on consumption and cognition: a systematic review and meta-analysis of experimental studies

    Directory of Open Access Journals (Sweden)

    Kaidy Stautz

    2016-06-01

    Full Text Available Abstract Background Restricting marketing of alcoholic products is purported to be a cost-effective intervention to reduce alcohol consumption. The strength of evidence supporting this claim is contested. This systematic review aimed to assess immediate effects of exposure to alcohol marketing on alcoholic beverage consumption and related cognitions. Methods Electronic searches of nine databases, supplemented with reference list searches and forward citation tracking, were used to identify randomised, experimental studies assessing immediate effects of exposure to alcohol marketing communications on objective alcohol consumption (primary outcome, explicit or implicit alcohol-related cognitions, or selection without purchasing (secondary outcomes. Study limitations were assessed using the Cochrane Risk of Bias tool. Random and fixed effects meta-analyses were conducted to estimate effect sizes. Results Twenty four studies met the eligibility criteria. A meta-analysis integrating seven studies (758 participants, all students found that viewing alcohol advertisements increased immediate alcohol consumption relative to viewing non-alcohol advertisements (SMD = 0.20, 95 % CI = 0.05, 0.34. A meta-analysis integrating six studies (631 participants, all students did not find that viewing alcohol portrayals in television programmes or films increased consumption (SMD = 0.16, 95 % CI = −0.05, 0.37. Meta-analyses of secondary outcome data found that exposure to alcohol portrayals increased explicit alcohol-related cognitions, but did not find that exposure to alcohol advertisements influenced explicit or implicit alcohol-related cognitions. Confidence in results is diminished by underpowered analyses and unclear risk of bias. Conclusions Viewing alcohol advertisements (but not alcohol portrayals may increase immediate alcohol consumption by small amounts, equivalent to between 0.39 and 2.67 alcohol units for males and between 0.25 and 1

  9. OHBM 2017: Practical intensity based meta-analysis

    OpenAIRE

    Maumet, Camille

    2017-01-01

    "Practical intensity-based meta-analysis" slides from my talk in the OHBM 2017 educational talk on Neuroimaging meta-analysis.http://www.humanbrainmapping.org/files/2017/ED Courses/Neuroimaging Meta-Analysis.pdf

  10. Age differences in the effect of framing on risky choice: A meta-analysis.

    Science.gov (United States)

    Best, Ryan; Charness, Neil

    2015-09-01

    The framing of decision scenarios in terms of potential gains versus losses has been shown to influence choice preferences between sure and risky options. Normative cognitive changes associated with aging have been known to affect decision making, which has led to a number of studies investigating the influence of aging on the effect of framing. Mata, Josef, Samanez-Larkin, and Hertwig (2011) systematically reviewed the available literature using a meta-analytic approach, but did not include tests of homogeneity or subsequent moderator variable analyses. The current review serves to extend the previous analysis to include such tests as well as update the pool of studies available for analysis. Results for both positively and negatively framed conditions were reviewed using 2 meta-analyses encompassing data collected from 3,232 subjects across 18 studies. Deviating from the previous results, the current analysis found a tendency for younger adults to choose the risky option more often than older adults for positively framed items. Moderator variable analyses found this effect likely to be driven by the specific decision scenario, showing a significant effect, with younger adults choosing the risky option more often in small-amount financial and large-amount mortality-based scenarios. For negatively framed items, the current review found no overall age difference in risky decision making, confirming the results from the prior meta-analysis. Moderator variable analyses conducted to address heterogeneity found younger adults to be more likely than older adults to choose the risky option for negatively framed high-amount mortality-based decision scenarios. Practical implications for older adults are discussed. (c) 2015 APA, all rights reserved).

  11. MetaEasy: A Meta-Analysis Add-In for Microsoft Excel

    Directory of Open Access Journals (Sweden)

    Evangelos Kontopantelis

    2009-04-01

    Full Text Available Meta-analysis is a statistical methodology that combines or integrates the results ofseveral independent clinical trials considered by the analyst to be `combinable' (Huque1988. However, completeness and user-friendliness are uncommon both in specialisedmeta-analysis software packages and in mainstream statistical packages that have to relyon user-written commands. We implemented the meta-analysis methodology in an Mi-crosoft Excel add-in which is freely available and incorporates more meta-analysis models(including the iterative maximum likelihood and prole likelihood than are usually avail-able, while paying particular attention to the user-friendliness of the package.

  12. A meta-analysis of serious digital games for healthy lifestyle promotion

    Science.gov (United States)

    Several systematic reviews have described health-promoting effects of serious games, but so far no meta-analysis has been reported. This paper presents a meta-analysis of 54 serious digital game studies for healthy lifestyle promotion, in which we investigated the overall effectiveness of serious di...

  13. Microarray Meta-Analysis Identifies Acute Lung Injury Biomarkers in Donor Lungs That Predict Development of Primary Graft Failure in Recipients

    Science.gov (United States)

    Haitsma, Jack J.; Furmli, Suleiman; Masoom, Hussain; Liu, Mingyao; Imai, Yumiko; Slutsky, Arthur S.; Beyene, Joseph; Greenwood, Celia M. T.; dos Santos, Claudia

    2012-01-01

    Objectives To perform a meta-analysis of gene expression microarray data from animal studies of lung injury, and to identify an injury-specific gene expression signature capable of predicting the development of lung injury in humans. Methods We performed a microarray meta-analysis using 77 microarray chips across six platforms, two species and different animal lung injury models exposed to lung injury with or/and without mechanical ventilation. Individual gene chips were classified and grouped based on the strategy used to induce lung injury. Effect size (change in gene expression) was calculated between non-injurious and injurious conditions comparing two main strategies to pool chips: (1) one-hit and (2) two-hit lung injury models. A random effects model was used to integrate individual effect sizes calculated from each experiment. Classification models were built using the gene expression signatures generated by the meta-analysis to predict the development of lung injury in human lung transplant recipients. Results Two injury-specific lists of differentially expressed genes generated from our meta-analysis of lung injury models were validated using external data sets and prospective data from animal models of ventilator-induced lung injury (VILI). Pathway analysis of gene sets revealed that both new and previously implicated VILI-related pathways are enriched with differentially regulated genes. Classification model based on gene expression signatures identified in animal models of lung injury predicted development of primary graft failure (PGF) in lung transplant recipients with larger than 80% accuracy based upon injury profiles from transplant donors. We also found that better classifier performance can be achieved by using meta-analysis to identify differentially-expressed genes than using single study-based differential analysis. Conclusion Taken together, our data suggests that microarray analysis of gene expression data allows for the detection of

  14. Is the perceived placebo effect comparable between adults and children? A meta-regression analysis.

    Science.gov (United States)

    Janiaud, Perrine; Cornu, Catherine; Lajoinie, Audrey; Djemli, Amina; Cucherat, Michel; Kassai, Behrouz

    2017-01-01

    A potential larger perceived placebo effect in children compared with adults could influence the detection of the treatment effect and the extrapolation of the treatment benefit from adults to children. This study aims to explore this potential difference, using a meta-epidemiological approach. A systematic review of the literature was done to identify trials included in meta-analyses evaluating a drug intervention with separate data for adults and children. The standardized mean change and the proportion of responders (binary outcomes) were used to calculate the perceived placebo effect. A meta-regression analysis was conducted to test for the difference between adults and children of the perceived placebo effect. For binary outcomes, the perceived placebo effect was significantly more favorable in children compared with adults (β = 0.13; P = 0.001). Parallel group trials (β = -1.83; P < 0.001), subjective outcomes (β = -0.76; P < 0.001), and the disease type significantly influenced the perceived placebo effect. The perceived placebo effect is different between adults and children for binary outcomes. This difference seems to be influenced by the design, the disease, and outcomes. Calibration of new studies for children should consider cautiously the placebo effect in children.

  15. Effect of melatonin on nocturnal blood pressure: meta-analysis of randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Laudon M

    2011-09-01

    Full Text Available Ehud Grossman1,4, Moshe Laudon2, Nava Zisapel2,31Department of Internal Medicine D and Hypertension Unit, The Chaim Sheba Medical Center, Tel-Hashomer, Israel; 2Neurim Pharmaceuticals Ltd, Tel Aviv, Israel and 3Department of Neurobiology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel; 4Sackler School of Medicine, Tel Aviv University, Tel Aviv, IsraelBackground: Patients with nocturnal hypertension are at higher risk for cardiovascular complications such as myocardial infarction and cerebrovascular insult. Published studies inconsistently reported decreases in nocturnal blood pressure with melatonin.Methods: A meta-analysis of the efficacy and safety of exogenous melatonin in ameliorating nocturnal blood pressure was performed using a random effects model of all studies fitting the inclusion criteria, with subgroup analysis of fast-release versus controlled-release preparations.Results: Seven trials (three of controlled-release and four of fast-release melatonin with 221 participants were included. Meta-analysis of all seven studies did not reveal significant effects of melatonin versus placebo on nocturnal blood pressure. However, subgroup analysis revealed that controlled-release melatonin significantly reduced nocturnal blood pressure whereas fast-release melatonin had no effect. Systolic blood pressure decreased significantly with controlled-release melatonin (-6.1 mmHg; 95% confidence interval [CI] -10.7 to -1.5; P = 0.009 but not fast-release melatonin (-0.3 mmHg; 95% CI -5.9 to 5.30; P = 0.92. Diastolic blood pressure also decreased significantly with controlled-release melatonin (-3.5 mmHg; 95% CI -6.1 to -0.9; P = 0.009 but not fast-release melatonin (-0.2 mmHg; 95% CI -3.8 to 3.3; P = 0.89. No safety concerns were raised.Conclusion: Add-on controlled-release melatonin to antihypertensive therapy is effective and safe in ameliorating nocturnal hypertension, whereas fast-release melatonin is ineffective. It is necessary

  16. Vitamin D and depression: a systematic review and meta-analysis comparing studies with and without biological flaws.

    Science.gov (United States)

    Spedding, Simon

    2014-04-11

    Efficacy of Vitamin D supplements in depression is controversial, awaiting further literature analysis. Biological flaws in primary studies is a possible reason meta-analyses of Vitamin D have failed to demonstrate efficacy. This systematic review and meta-analysis of Vitamin D and depression compared studies with and without biological flaws. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was undertaken through four databases for randomized controlled trials (RCTs). Studies were critically appraised for methodological quality and biological flaws, in relation to the hypothesis and study design. Meta-analyses were performed for studies according to the presence of biological flaws. The 15 RCTs identified provide a more comprehensive evidence-base than previous systematic reviews; methodological quality of studies was generally good and methodology was diverse. A meta-analysis of all studies without flaws demonstrated a statistically significant improvement in depression with Vitamin D supplements (+0.78 CI +0.24, +1.27). Studies with biological flaws were mainly inconclusive, with the meta-analysis demonstrating a statistically significant worsening in depression by taking Vitamin D supplements (-1.1 CI -0.7, -1.5). Vitamin D supplementation (≥800 I.U. daily) was somewhat favorable in the management of depression in studies that demonstrate a change in vitamin levels, and the effect size was comparable to that of anti-depressant medication.

  17. Physical Activity and Cognitive Development: A Meta-Analysis.

    Science.gov (United States)

    Jackson, William M; Davis, Nicholas; Sands, Stephen A; Whittington, Robert A; Sun, Lena S

    2016-10-01

    inclusion. From these 18 studies, 8 were independently selected by 2 authors for inclusion in the final analysis; there were no selection discrepancies between authors with regard to the studies to be included. In all, 770 subjects were included, 339 in the control group and 431 in the intervention group. All 8 studies contained a measure of inhibitory control; no other domain of executive function was measured frequently enough to perform meta-analysis, so only measures of inhibitory control were pooled and analyzed. A Cohen d effect size was calculated for each measure using the method of Morris for controlled pre-post control measurement studies. The studies were then combined in a random effects model using Comprehensive Meta Analysis software (Biostat, Englewood, NJ) for Windows (Microsoft, Redmond, WA). All studies showed a positive effect of regular exercise with improvements in measures of inhibitory control, but none were statistically significant for this measure. When pooled, the model revealed a combined Cohen d effect size of 0.2 (95% confidence interval, 0.03-0.37; P=0.021), indicating a small improvement of inhibitory control with long-term physical activity. Heterogeneity was very low (I=0). Many studies used different neuropsychological tests to assess inhibitory control, which may have introduced unforeseen confounders. Other domains of executive functions were not measured frequently enough to perform meta-analysis. Despite attempts to gather unpublished data, positive results were observed in all of the included studies, raising the possibility of publication bias. Increased regular physical activity is associated with a small and measurable, improvement in neuropsychological tests of executive functions, specifically inhibitory control. Executive functions play an important role in complex behavior, and may contribute to academic and career achievement as well as success in social interaction. This finding provides support for the important interaction

  18. Effect of Active Workstation on Energy Expenditure and Job Performance: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Cao, Chunmei; Liu, Yu; Zhu, Weimo; Ma, Jiangjun

    2016-05-01

    Recently developed active workstation could become a potential means for worksite physical activity and wellness promotion. The aim of this review was to quantitatively examine the effectiveness of active workstation in energy expenditure and job performance. The literature search was conducted in 6 databases (PubMed, SPORTDiscuss, Web of Science, ProQuest, ScienceDirect, and Scopuse) for articles published up to February 2014, from which a systematic review and meta-analysis was conducted. The cumulative analysis for EE showed there was significant increase in EE using active workstation [mean effect size (MES): 1.47; 95% confidence interval (CI): 1.22 to 1.72, P job performance indicated 2 findings: (1) active workstation did not affect selective attention, processing speed, speech quality, reading comprehension, interpretation and accuracy of transcription; and (2) it could decrease the efficiency of typing speed (MES: -0.55; CI: -0.88 to -0.21, P job performance were significantly lower, others were not. As a result there was little effect on real-life work productivity if we made a good arrangement of job tasks.

  19. A meta-analysis of the effects of β-adrenergic blockers in chronic heart failure.

    Science.gov (United States)

    Zhang, Xiaojian; Shen, Chengwu; Zhai, Shujun; Liu, Yukun; Yue, Wen-Wei; Han, Li

    2016-10-01

    Adrenergic β-blockers are drugs that bind to, but do not activate β-adrenergic receptors. Instead they block the actions of β-adrenergic agonists and are used for the treatment of various diseases such as cardiac arrhythmias, angina pectoris, myocardial infarction, hypertension, headache, migraines, stress, anxiety, prostate cancer, and heart failure. Several meta-analysis studies have shown that β-blockers improve the heart function and reduce the risks of cardiovascular events, rate of mortality, and sudden death through chronic heart failure (CHF) of patients. The present study identified results from recent meta-analyses of β-adrenergic blockers and their usefulness in CHF. Databases including Medline/Embase/Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed were searched for the periods May, 1985 to March, 2011 and June, 2013 to August, 2015, and a number of studies identified. Results of those studies showed that use of β-blockers was associated with decreased sudden cardiac death in patients with heart failure. However, contradictory results have also been reported. The present meta-analysis aimed to determine the efficacy of β-blockers on mortality and morbidity in patients with heart failure. The results showed that mortality was significantly reduced by β-blocker treatment prior to the surgery of heart failure patients. The results from the meta-analysis studies showed that β-blocker treatment in heart failure patients correlated with a significant decrease in long-term mortality, even in patients that meet one or more exclusion criteria of the MERIT-HF study. In summary, the findings of the current meta-analysis revealed beneficial effects different β-blockers have on patients with heart failure or related heart disease.

  20. Effect of zinc intake on mental and motor development in infants: a meta-analysis.

    Science.gov (United States)

    Nissensohn, Mariela; Sánchez-Villegas, Almudena; Fuentes Lugo, Daniel; Henríquez Sánchez, Patricia; Doreste Alonso, Jorge; Skinner, Anna L; Medina, Marisol W; Lowe, Nicola M; Hall Moran, Victoria; Serra-Majem, Lluis

    2013-01-01

    A systematic review and meta-analysis of available randomized controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on mental and motor development in infants. Out of 5500 studies identified through electronic searches and reference lists, 5 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on mental and motor development was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional situation, and risk of bias. Indices of mental and motor development assessed were the Mental Development Index (MDI) and Psychomotor Development Index (PDI). Additionally we carried out a sensitivity analysis. The pooled β was -0.01 (95 %CI -0.02, 0) for MDI and 0 (95 %CI -0.03, 0.02) for PDI, with a substantial heterogeneity in both analyses. When we performed a meta-regression, the effect of Zn supplementation on MDI changed depending on the dose of supplementation. Regarding PDI, there was a differential effect of Zn intake depending on intervention duration, dose of supplementation, nutritional situation, and risk of bias. Zn supplementation showed a negative, weak and significant effect on PDI score in those studies with a length of 4 to 20 weeks (β= -0.05; CI 95 % -0.06 to -0.04). In conclusion, no association was found between Zn intake and mental and motor development in infants. Further standardized research is urgently needed to clarify the role of Zn supplementation upon infant mental and motor development, particularly in Europe.