A Thematic-Based Meta Analytic Study Regarding the Effect of Creativity on Academic Success and Learning Retention

Science.gov (United States)

Özdas, Faysal; Batdi, Veli

2017-01-01

This thematic-based meta-analytic study aims to examine the effect of creativity on the academic success and learning retention scores of students. In the context of this aim, 18 out of 225 studies regarding creativity that were carried out between 2001 and 2011 have been obtained from certain national and international databases. The studies…

On the Multilevel Nature of Meta-Analysis: A Tutorial, Comparison of Software Programs, and Discussion of Analytic Choices.

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Pastor, Dena A; Lazowski, Rory A

2018-01-01

The term "multilevel meta-analysis" is encountered not only in applied research studies, but in multilevel resources comparing traditional meta-analysis to multilevel meta-analysis. In this tutorial, we argue that the term "multilevel meta-analysis" is redundant since all meta-analysis can be formulated as a special kind of multilevel model. To clarify the multilevel nature of meta-analysis the four standard meta-analytic models are presented using multilevel equations and fit to an example data set using four software programs: two specific to meta-analysis (metafor in R and SPSS macros) and two specific to multilevel modeling (PROC MIXED in SAS and HLM). The same parameter estimates are obtained across programs underscoring that all meta-analyses are multilevel in nature. Despite the equivalent results, not all software programs are alike and differences are noted in the output provided and estimators available. This tutorial also recasts distinctions made in the literature between traditional and multilevel meta-analysis as differences between meta-analytic choices, not between meta-analytic models, and provides guidance to inform choices in estimators, significance tests, moderator analyses, and modeling sequence. The extent to which the software programs allow flexibility with respect to these decisions is noted, with metafor emerging as the most favorable program reviewed.

Behavioural effects of advanced cruise control use : a meta-analytic approach.

NARCIS (Netherlands)

Dragutinovic, N. Brookhuis, K.A. Hagenzieker, M.P. & Marchau, V.A.W.J.

2006-01-01

In this study, a meta-analytic approach was used to analyse effects of Advanced Cruise Control (ACC) on driving behaviour reported in seven driving simulator studies. The effects of ACC on three consistent outcome measures, namely, driving speed, headway and driver workload have been analysed. The

The Significance of Attachment Quality for Obesity : A Meta-Analytic Review

NARCIS (Netherlands)

Diener, Marc J.; Geenen, Rinie; Koelen, Jurrijn A.; Aarts, Floor; Gerdes, Victor E. A.; Brandjes, Dees P. M.; Hinnen, Chris

2016-01-01

Theoretical considerations and empirical results suggest that attachment quality is relevant to obesity. This study used meta-analytic methods to systematically examine the empirical, peer-reviewed evidence regarding the relationship between attachment quality and body mass index (BMI) in separate

Total hip arthroplasty after a previous pelvic osteotomy: A systematic review and meta-analysis.

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Shigemura, T; Yamamoto, Y; Murata, Y; Sato, T; Tsuchiya, R; Wada, Y

2018-06-01

There are several reports regarding total hip arthroplasty (THA) after a previous pelvic osteotomy (PO). However, to our knowledge, until now there has been no formal systematic review and meta-analysis published to summarize the clinical results of THA after a previous PO. Therefore, we conducted a systematic review and meta-analysis of results of THA after a previous PO. We focus on these questions as follows: does a previous PO affect the results of subsequent THA, such as clinical outcomes, operative time, operative blood loss, and radiological parameters. Using PubMed, Web of Science, and Cochrane Library, we searched for relevant original papers. The pooling of data was performed using RevMan software (version 5.3, Cochrane Collaboration, Oxford, UK). A p-value50%, significant heterogeneity was assumed and a random-effects model was applied for the meta-analysis. A fixed-effects model was applied in the absence of significant heterogeneity. Eleven studies were included in this meta-analysis. The pooled results indicated that there was no significant difference in postoperative Merle D'Aubigne-Postel score (I 2 =0%, SMD=-0.15, 95% CI: -0.36 to 0.06, p=0.17), postoperative Harris hip score (I 2 =60%, SMD=-0.23, 95% CI: -0.50 to 0.05, p=0.10), operative time (I 2 =86%, SMD=0.37, 95% CI: -0.09 to 0.82, p=0.11), operative blood loss (I 2 =82%, SMD=0.23, 95% CI: -0.17 to 0.63, p=0.25), and cup abduction angle (I 2 =43%, SMD=-0.08, 95% CI: -0.25 to 0.09, p=0.38) between THA with and without a previous PO. However, cup anteversion angle of THA with a previous PO was significantly smaller than that of without a previous PO (I 2 =77%, SMD=-0.63, 95% CI: -1.13 to -0.13, p=0.01). Systematic review and meta-analysis of results of THA after a previous PO was performed. A previous PO did not affect the results of subsequent THA, except for cup anteversion. Because of the low quality evidence currently available, high-quality randomized controlled trials are required

Enhancing Treatment Outcome of Patients at Risk of Treatment Failure: Meta-Analytic and Mega-Analytic Review of a Psychotherapy Quality Assurance System

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Shimokawa, Kenichi; Lambert, Michael J.; Smart, David W.

2010-01-01

Objective: Outcome research has documented worsening among a minority of the patient population (5% to 10%). In this study, we conducted a meta-analytic and mega-analytic review of a psychotherapy quality assurance system intended to enhance outcomes in patients at risk of treatment failure. Method: Original data from six major studies conducted…

Associations between rejection sensitivity and mental health outcomes : A meta-analytic review

NARCIS (Netherlands)

Gao, S.; Assink, M.; Cipriani, A.; Lin, K.

2017-01-01

Rejection sensitivity is a personality disposition characterized by oversensitivity to social rejection. Using a three-level meta-analytic model, 75 studies were reviewed that examined associations between rejection sensitivity and five mental health outcomes: depression, anxiety, loneliness,

The link between employee attitudes and employee effectiveness: Data matrix of meta-analytic estimates based on 1161 unique correlations

Directory of Open Access Journals (Sweden)

Michael M. Mackay

2016-09-01

Full Text Available This article offers a correlation matrix of meta-analytic estimates between various employee job attitudes (i.e., Employee engagement, job satisfaction, job involvement, and organizational commitment and indicators of employee effectiveness (i.e., Focal performance, contextual performance, turnover intention, and absenteeism. The meta-analytic correlations in the matrix are based on over 1100 individual studies representing over 340,000 employees. Data was collected worldwide via employee self-report surveys. Structural path analyses based on the matrix, and the interpretation of the data, can be found in “Investigating the incremental validity of employee engagement in the prediction of employee effectiveness: a meta-analytic path analysis” (Mackay et al., 2016 [1]. Keywords: Meta-analysis, Job attitudes, Job performance, Employee, Engagement, Employee effectiveness

A Meta-Analytic Review of School-Based Prevention for Cannabis Use

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Porath-Waller, Amy J.; Beasley, Erin; Beirness, Douglas J.

2010-01-01

This investigation used meta-analytic techniques to evaluate the effectiveness of school-based prevention programming in reducing cannabis use among youth aged 12 to 19. It summarized the results from 15 studies published in peer-reviewed journals since 1999 and identified features that influenced program effectiveness. The results from the set of…

Job burnout and employee engagement : A meta-analytic examination of construct proliferation

NARCIS (Netherlands)

Cole, M.S.; Walter, F.; Bedeian, A.G.; O'Boyle, E.H.

Drawing on 50 unique samples (from 37 studies), the authors used meta-analytical techniques to assess the extent to which job burnout and employee engagement are independent and useful constructs. The authors found that (a) dimension-level correlations between burnout and engagement are high, (b)

Impairment of sperm DNA methylation in male infertility: a meta-analytic study.

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Santi, D; De Vincentis, S; Magnani, E; Spaggiari, G

2017-07-01

Considering the widespread use of assisted reproductive techniques (ART), DNA methylation of specific genes involved in spermatogenesis achieves increasingly clinical relevance, representing a possible explanation of increased incidence of syndromes related to genomic imprinting in medically assisted pregnancies. Several trials suggested a relationship between male sub-fertility and sperm DNA methylation, although its weight on seminal parameters alteration is still a matter of debate. To evaluate whether aberrant sperm DNA methylation of imprinted genes is associated with impaired sperm parameters. Meta-analysis of controlled clinical trials evaluating imprinted genes sperm DNA methylation comparing men with idiopathic infertility to fertile controls. Twenty-four studies were included, allowing a meta-analytic evaluation for H19, MEST, SNRPN, and LINE-1. When a high heterogeneity of the results was demonstrated, the random effect model was used. H19 methylation levels resulted significantly lower in 879 infertile compared with 562 fertile men (7.53%, 95% CI: 5.14-9.93%, p male infertility is associated with altered sperm methylation at H19, MEST, and SNRPN. Although its role in infertility remains unclear, sperm DNA methylation could be associated with the epigenetic risk in ART. In this setting, before proposing this analysis in clinical practice, an accurate identification of the most representative genes and a cost-effectiveness evaluation should be assessed in ad hoc prospective studies. © 2017 American Society of Andrology and European Academy of Andrology.

Using meta-analytic path analysis to test theoretical predictions in health behavior: An illustration based on meta-analyses of the theory of planned behavior.

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Hagger, Martin S; Chan, Derwin K C; Protogerou, Cleo; Chatzisarantis, Nikos L D

2016-08-01

Synthesizing research on social cognitive theories applied to health behavior is an important step in the development of an evidence base of psychological factors as targets for effective behavioral interventions. However, few meta-analyses of research on social cognitive theories in health contexts have conducted simultaneous tests of theoretically-stipulated pattern effects using path analysis. We argue that conducting path analyses of meta-analytic effects among constructs from social cognitive theories is important to test nomological validity, account for mediation effects, and evaluate unique effects of theory constructs independent of past behavior. We illustrate our points by conducting new analyses of two meta-analyses of a popular theory applied to health behaviors, the theory of planned behavior. We conducted meta-analytic path analyses of the theory in two behavioral contexts (alcohol and dietary behaviors) using data from the primary studies included in the original meta-analyses augmented to include intercorrelations among constructs and relations with past behavior missing from the original analysis. Findings supported the nomological validity of the theory and its hypotheses for both behaviors, confirmed important model processes through mediation analysis, demonstrated the attenuating effect of past behavior on theory relations, and provided estimates of the unique effects of theory constructs independent of past behavior. Our analysis illustrates the importance of conducting a simultaneous test of theory-stipulated effects in meta-analyses of social cognitive theories applied to health behavior. We recommend researchers adopt this analytic procedure when synthesizing evidence across primary tests of social cognitive theories in health. Copyright © 2016 Elsevier Inc. All rights reserved.

Executive Function and Reading Comprehension: A Meta-Analytic Review

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Follmer, D. Jake

2018-01-01

This article presents a meta-analytic review of the relation between executive function and reading comprehension. Results (N = 6,673) supported a moderate positive association between executive function and reading comprehension (r = 0.36). Moderator analyses suggested that correlations between executive function and reading comprehension did not…

What Limits the Encoding Effect of Note-Taking? A Meta-Analytic Examination

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Kobayashi, K.

2005-01-01

Previous meta-analyses indicate that the overall encoding effect of note-taking is positive but modest. This meta-analysis of 57 note-taking versus no note-taking comparison studies explored what limits the encoding effect by examining the moderating influence of seven variables: intervention, schooling level, presentation mode and length, test…

Matching Procedures in Autism Research: Evidence from Meta-Analytic Studies

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Shaked, Michal; Yirmiya, Nurit

2004-01-01

In this paper, we summarize some of our findings from a series of three meta-analyses and discuss their implications for autism research. In the first meta-analysis, we examined studies addressing the theory of mind hypothesis in autism. This analysis revealed that theory of mind disabilities are not unique to autism, although what may be unique…

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

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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…

Updated Meta-Analysis of Learner Control within Educational Technology

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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…

Random-Effects Models for Meta-Analytic Structural Equation Modeling: Review, Issues, and Illustrations

Science.gov (United States)

Cheung, Mike W.-L.; Cheung, Shu Fai

2016-01-01

Meta-analytic structural equation modeling (MASEM) combines the techniques of meta-analysis and structural equation modeling for the purpose of synthesizing correlation or covariance matrices and fitting structural equation models on the pooled correlation or covariance matrix. Both fixed-effects and random-effects models can be defined in MASEM.…

Violent video game effects on aggression, empathy, and prosocial behavior in Eastern and Western countries: A meta-analytic review

NARCIS (Netherlands)

Anderson, C.A.; Shibuya, A.; Ihori, N.; Swing, E.L.; Bushman, B.J.; Sakamoto, A.; Rothstein, H.R.; Saleem, M.; Barlett, C.P.

2010-01-01

Meta-analytic procedures were used to test the effects of violent video games on aggressive behavior, aggressive cognition, aggressive affect, physiological arousal, empathy/desensitization, and prosocial behavior. Unique features of this meta-analytic review include (a) more restrictive

Atheists and Agnostics Are More Reflective than Religious Believers: Four Empirical Studies and a Meta-Analysis

Science.gov (United States)

Pennycook, Gordon; Ross, Robert M.; Koehler, Derek J.; Fugelsang, Jonathan A.

2016-01-01

Individual differences in the mere willingness to think analytically has been shown to predict religious disbelief. Recently, however, it has been argued that analytic thinkers are not actually less religious; rather, the putative association may be a result of religiosity typically being measured after analytic thinking (an order effect). In light of this possibility, we report four studies in which a negative correlation between religious belief and performance on analytic thinking measures is found when religious belief is measured in a separate session. We also performed a meta-analysis on all previously published studies on the topic along with our four new studies (N = 15,078, k = 31), focusing specifically on the association between performance on the Cognitive Reflection Test (the most widely used individual difference measure of analytic thinking) and religious belief. This meta-analysis revealed an overall negative correlation (r) of -.18, 95% CI [-.21, -.16]. Although this correlation is modest, self-identified atheists (N = 133) scored 18.7% higher than religiously affiliated individuals (N = 597) on a composite measure of analytic thinking administered across our four new studies (d = .72). Our results indicate that the association between analytic thinking and religious disbelief is not caused by a simple order effect. There is good evidence that atheists and agnostics are more reflective than religious believers. PMID:27054566

Multi-site study of additive genetic effects on fractional anisotropy of cerebral white matter: comparing meta and mega analytical approaches for data pooling

Science.gov (United States)

Kochunov, Peter; Jahanshad, Neda; Sprooten, Emma; Nichols, Thomas E.; Mandl, René C.; Almasy, Laura; Booth, Tom; Brouwer, Rachel M.; Curran, Joanne E.; de Zubicaray, Greig I.; Dimitrova, Rali; Duggirala, Ravi; Fox, Peter T.; Hong, L. Elliot; Landman, Bennett A.; Lemaitre, Hervé; Lopez, Lorna; Martin, Nicholas G.; McMahon, Katie L.; Mitchell, Braxton D.; Olvera, Rene L.; Peterson, Charles P.; Starr, John M.; Sussmann, Jessika E.; Toga, Arthur W.; Wardlaw, Joanna M.; Wright, Margaret J.; Wright, Susan N.; Bastin, Mark E.; McIntosh, Andrew M.; Boomsma, Dorret I.; Kahn, René S.; den Braber, Anouk; de Geus, Eco JC; Deary, Ian J.; Hulshoff Pol, Hilleke E.; Williamson, Douglas E.; Blangero, John; van ’t Ent, Dennis; Thompson, Paul M.; Glahn, David C.

2014-01-01

Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9–85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large “mega-family”. We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. PMID:24657781

The role of the putamen in language: a meta-analytic connectivity modeling study.

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Viñas-Guasch, Nestor; Wu, Yan Jing

2017-12-01

The putamen is a subcortical structure that forms part of the dorsal striatum of basal ganglia, and has traditionally been associated with reinforcement learning and motor control, including speech articulation. However, recent studies have shown involvement of the left putamen in other language functions such as bilingual language processing (Abutalebi et al. 2012) and production, with some authors arguing for functional segregation of anterior and posterior putamen (Oberhuber et al. 2013). A further step in exploring the role of putamen in language would involve identifying the network of coactivations of not only the left, but also the right putamen, given the involvement of right hemisphere in high order language functions (Vigneau et al. 2011). Here, a meta-analytic connectivity modeling technique was used to determine the patterns of coactivation of anterior and bilateral putamen in the language domain. Based on previous evidence, we hypothesized that left putamen coactivations would include brain regions directly associated with language processing, whereas right putamen coactivations would encompass regions involved in broader semantic processes, such as memory and visual imagery. The results showed that left anterior putamen coactivated with clusters predominantly in left hemisphere, encompassing regions directly associated with language processing, a left posterior putamen network spanning both hemispheres, and cerebellum. In right hemisphere, coactivations were in both hemispheres, in regions associated with visual and orthographic processing. These results confirm the differential involvement of right and left putamen in different language components, thus highlighting the need for further research into the role of putamen in language.

Meta-connectomics: human brain network and connectivity meta-analyses.

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Crossley, N A; Fox, P T; Bullmore, E T

2016-04-01

Abnormal brain connectivity or network dysfunction has been suggested as a paradigm to understand several psychiatric disorders. We here review the use of novel meta-analytic approaches in neuroscience that go beyond a summary description of existing results by applying network analysis methods to previously published studies and/or publicly accessible databases. We define this strategy of combining connectivity with other brain characteristics as 'meta-connectomics'. For example, we show how network analysis of task-based neuroimaging studies has been used to infer functional co-activation from primary data on regional activations. This approach has been able to relate cognition to functional network topology, demonstrating that the brain is composed of cognitively specialized functional subnetworks or modules, linked by a rich club of cognitively generalized regions that mediate many inter-modular connections. Another major application of meta-connectomics has been efforts to link meta-analytic maps of disorder-related abnormalities or MRI 'lesions' to the complex topology of the normative connectome. This work has highlighted the general importance of network hubs as hotspots for concentration of cortical grey-matter deficits in schizophrenia, Alzheimer's disease and other disorders. Finally, we show how by incorporating cellular and transcriptional data on individual nodes with network models of the connectome, studies have begun to elucidate the microscopic mechanisms underpinning the macroscopic organization of whole-brain networks. We argue that meta-connectomics is an exciting field, providing robust and integrative insights into brain organization that will likely play an important future role in consolidating network models of psychiatric disorders.

Violent Video Game Effects on Aggression, Empathy, and Prosocial Behavior in Eastern and Western Countries: A Meta-Analytic Review

Science.gov (United States)

Anderson, Craig A.; Shibuya, Akiko; Ihori, Nobuko; Swing, Edward L.; Bushman, Brad J.; Sakamoto, Akira; Rothstein, Hannah R.; Saleem, Muniba

2010-01-01

Meta-analytic procedures were used to test the effects of violent video games on aggressive behavior, aggressive cognition, aggressive affect, physiological arousal, empathy/desensitization, and prosocial behavior. Unique features of this meta-analytic review include (a) more restrictive methodological quality inclusion criteria than in past…

Online Programs as Tools to Improve Parenting: A meta-analytic review

NARCIS (Netherlands)

Prof. Dr. Jo J.M.A Hermanns; Prof. Dr. Ruben R.G. Fukkink; dr. Christa C.C. Nieuwboer

2013-01-01

Background. A number of parenting programs, aimed at improving parenting competencies,have recently been adapted or designed with the use of online technologies. Although webbased services have been claimed to hold promise for parent support, a meta-analytic review of online parenting interventions

Online programs as tools to improve parenting: A meta-analytic review

NARCIS (Netherlands)

Nieuwboer, C.C.; Fukkink, R.G.; Hermanns, J.M.A.

2013-01-01

Background: A number of parenting programs, aimed at improving parenting competencies, have recently been adapted or designed with the use of online technologies. Although web-based services have been claimed to hold promise for parent support, a meta-analytic review of online parenting

Thresholds for statistical and clinical significance in systematic reviews with meta-analytic methods

DEFF Research Database (Denmark)

Jakobsen, Janus Christian; Wetterslev, Jorn; Winkel, Per

2014-01-01

BACKGROUND: Thresholds for statistical significance when assessing meta-analysis results are being insufficiently demonstrated by traditional 95% confidence intervals and P-values. Assessment of intervention effects in systematic reviews with meta-analysis deserves greater rigour. METHODS......: Methodologies for assessing statistical and clinical significance of intervention effects in systematic reviews were considered. Balancing simplicity and comprehensiveness, an operational procedure was developed, based mainly on The Cochrane Collaboration methodology and the Grading of Recommendations...... Assessment, Development, and Evaluation (GRADE) guidelines. RESULTS: We propose an eight-step procedure for better validation of meta-analytic results in systematic reviews (1) Obtain the 95% confidence intervals and the P-values from both fixed-effect and random-effects meta-analyses and report the most...

What is Informal Learning and What are its Antecedents? An Integrative and Meta-Analytic Review

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2014-07-01

Cerasoli, C. P., Nicklin, J. M., & Ford, M. T. (2014). Intrinsic motivation and extrinsic incentives jointly predict performance: A 40-year meta... motivation : A meta-analytic path analysis of 20 years of research. Journal of Applied Psychology , 85, 678-707. Cooper, H. (2003). Editorial...error management training: A meta-analysis. Journal of Applied Psychology , 93, 59-69. Klein, H. J., Noe, R. A., & Wang, C. W. (2006). Motivation to

Internationalization and firm performance in Chindia countries: a meta-analytic review

Directory of Open Access Journals (Sweden)

LINDA SCHULZE

Full Text Available For more than four decades, researchers have examined theoretically and empirically the relationship between internationalization and firm performance. While existing studies have provided important contributions, the stream of research still lacks consistency due to ambiguous findings on the internationalization-firm performance relationship. Moreover, previous research has often been limited to developed countries. The present study focuses on the emerging Chindia countries and determines the direction and the strength of the internationalization-firm performance relationship. Additionally, we have identified moderators of the relationship. Drawing on 21 studies, based on 9026 firms, we utilize a meta-analytic review to assess our hypotheses. Our results show that there is a significant and positive internationalization-firm performance relationship in Chindia countries. The effect of internationalization in India and China does not significantly differ. Moreover, we find that the effect of internationalization is significantly stronger in the United States as compared to the Chindia countries. The time period of data collection did not play an important role as a moderator. The present study contributes to the International Business literature by examining how and to which extent internationalization influences firm performance and offers implications for theory and practice as well as recommendations for future research.

A review of cognitive conflicts research: a meta-analytic study of prevalence and relation to symptoms

Directory of Open Access Journals (Sweden)

Montesano A

2015-12-01

Full Text Available Adrián Montesano,1 María Angeles López-González,2 Luis Angel Saúl,2 Guillem Feixas1 1Department of Personality, Assessment and Psychological Treatments, University of Barcelona, Barcelona, 2Department of Personality, Assessment and Psychological Treatments, Faculty of Psychology, National Distance Education University, Madrid, Spain Abstract: Recent research has highlighted the role of implicative dilemmas in a variety of clinical conditions. These dilemmas are a type of cognitive conflict, in which different aspects of the self are countered in such a way that a desired change in a personal dimension (eg, symptom improvement may be hindered by the need of personal coherence in another dimension. The aim of this study was to summarize, using a meta-analytical approach, the evidence relating to the presence and the level of this conflict, as well as its relationship with well-being, in various clinical samples. A systematic review using multiple electronic databases found that out of 37 articles assessed for eligibility, nine fulfilled the inclusion criteria for meta-analysis. Random effects model was applied when computing mean effect sizes and testing for heterogeneity level. Statistically significant associations were observed between the clinical status and the presence of dilemmas, as well as level of conflict across several clinical conditions. Likewise, the level of conflict was associated with symptom severity. Results highlighted the clinical relevance and the transdiagnostic nature of implicative dilemmas. Keywords: implicative dilemmas, cognitive conflicts, intrapersonal conflicts, meta-analysis

Student Satisfaction in Higher Education: A Meta-Analytic Study

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Santini, Fernando de Oliveira; Ladeira, Wagner Junior; Sampaio, Claudio Hoffmann; da Silva Costa, Gustavo

2017-01-01

This paper discusses the results of a meta-analysis performed to identify key antecedent and consequent constructs of satisfaction in higher education. We offer an integrated model to achieve a better understanding of satisfaction in the context of higher education. To accomplish this objective, we identified 83 studies that were valid and…

Language and Verbal Short-Term Memory Skills in Children with Down Syndrome: A Meta-Analytic Review

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Naess, Kari-Anne B.; Lyster, Solveig-Alma Halaas; Hulme, Charles; Melby-Lervag, Monica

2011-01-01

This study presents a meta-analytic review of language and verbal short-term memory skills in children with Down syndrome. The study examines the profile of strengths and weaknesses in children with Down syndrome compared to typically developing children matched for nonverbal mental age. The findings show that children with Down syndrome have…

Violent media and hostile appraisals: A meta-analytic review.

Science.gov (United States)

Bushman, Brad J

2016-11-01

Hostile people tend to view the world as a hostile place. Although there are individual differences in hostile world-views, situational factors can also play a role. For example, scenes of violence in the mass media might influence people to view the world as a hostile place. This meta-analysis aggregates, for the first time, all studies that have investigated the link between exposure to violent media and hostile appraisals (e.g., perceiving the ambiguous actions by others as aggressive actions). This meta-analysis included 37 independent studies involving 10,410 participants. The results showed a "small" to "moderate" sized average correlation between exposure to violent media and hostile appraisals (r +  = .20, 95%CI = .14, .26). Significant correlations were found in experimental, cross-sectional, and longitudinal studies, indicating a triangulation of evidence. Effects were not correlated with participant gender. Effects were also stable over time. However, the link between exposure to violent media and hostile appraisals was positively related to age, perhaps because violent media can have cumulative effects over time. There was no evidence of publication bias. The findings from this meta-analysis are consistent with the General Aggression Model (e.g., Anderson, & Bushman, 2002; Annual Review of Psychology 53:27-51). These results compliment those from previous meta-analyses showing that violent media can increase aggressive thoughts, angry feelings, physiological arousal, and aggressive behavior. These findings also have practical significance, because people who view the world in a hostile manner are more likely to behave aggressively themselves. Aggr. Behav. 42:605-613, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

A Review of Level 2 Parent-Report Instruments Used to Screen Children Aged 1.5-5 for Autism: A Meta-Analytic Update

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Hampton, Justin; Strand, Paul S.

2015-01-01

The present study utilized meta-analytic procedures to estimate the diagnostic validity of instruments used to screen young children, ages 1.5-5 years, for autism. Five scales met inclusion criteria, and data from 18 studies contributed the meta-analysis. Results revealed that 4 of 5 scales met criteria for "good" validity, including two…

"Racial bias in mock juror decision-making: A meta-analytic review of defendant treatment": Correction to Mitchell et al. (2005).

Science.gov (United States)

2017-06-01

Reports an error in "Racial Bias in Mock Juror Decision-Making: A Meta-Analytic Review of Defendant Treatment" by Tara L. Mitchell, Ryann M. Haw, Jeffrey E. Pfeifer and Christian A. Meissner ( Law and Human Behavior , 2005[Dec], Vol 29[6], 621-637). In the article, all of the numbers in Appendix A were correct, but the signs were reversed for z' in a number of studies, which are listed. Also, in Appendix B, some values were incorrect, some signs were reversed, and some values were missing. The corrected appendix is included. (The following abstract of the original article appeared in record 2006-00971-001.) Common wisdom seems to suggest that racial bias, defined as disparate treatment of minority defendants, exists in jury decision-making, with Black defendants being treated more harshly by jurors than White defendants. The empirical research, however, is inconsistent--some studies show racial bias while others do not. Two previous meta-analyses have found conflicting results regarding the existence of racial bias in juror decision-making (Mazzella & Feingold, 1994, Journal of Applied Social Psychology, 24, 1315-1344; Sweeney & Haney, 1992, Behavioral Sciences and the Law, 10, 179-195). This research takes a meta-analytic approach to further investigate the inconsistencies within the empirical literature on racial bias in juror decision-making by defining racial bias as disparate treatment of racial out-groups (rather than focusing upon the minority group alone). Our results suggest that a small, yet significant, effect of racial bias in decision-making is present across studies, but that the effect becomes more pronounced when certain moderators are considered. The state of the research will be discussed in light of these findings. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Examining the Job-Related, Psychological, and Physical Outcomes of Workplace Sexual Harassment: A Meta-Analytic Review

Science.gov (United States)

Chan, Darius K-S.; Lam, Chun Bun; Chow, Suk Yee; Cheung, Shu Fai

2008-01-01

This study was designed to examine the job-related, psychological, and physical outcomes of sexual harassment in the workplace. Using a meta-analytic approach, we analyzed findings from 49 primary studies, with a total sample size of 89,382, to obtain estimates of the population mean effect size of the association between sexual harassment and…

A Meta-Analytic Review of Tactile-Cued Self-Monitoring Interventions Used by Students in Educational Settings

Science.gov (United States)

McDougall, Dennis; Ornelles, Cecily; Mersberg, Kawika; Amona, Kekama

2015-01-01

In this meta-analytic review, we critically evaluate procedures and outcomes from nine intervention studies in which students used tactile-cued self-monitoring in educational settings. Findings suggest that most tactile-cued self-monitoring interventions have moderate to strong effects, have emerged only recently, and have not yet achieved the…

Video game training does not enhance cognitive ability: A comprehensive meta-analytic investigation.

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Sala, Giovanni; Tatlidil, K Semir; Gobet, Fernand

2018-02-01

As a result of considerable potential scientific and societal implications, the possibility of enhancing cognitive ability by training has been one of the most influential topics of cognitive psychology in the last two decades. However, substantial research into the psychology of expertise and a recent series of meta-analytic reviews have suggested that various types of cognitive training (e.g., working memory training) benefit performance only in the trained tasks. The lack of skill generalization from one domain to different ones-that is, far transfer-has been documented in various fields of research such as working memory training, music, brain training, and chess. Video game training is another activity that has been claimed by many researchers to foster a broad range of cognitive abilities such as visual processing, attention, spatial ability, and cognitive control. We tested these claims with three random-effects meta-analytic models. The first meta-analysis (k = 310) examined the correlation between video game skill and cognitive ability. The second meta-analysis (k = 315) dealt with the differences between video game players and nonplayers in cognitive ability. The third meta-analysis (k = 359) investigated the effects of video game training on participants' cognitive ability. Small or null overall effect sizes were found in all three models. These outcomes show that overall cognitive ability and video game skill are only weakly related. Importantly, we found no evidence of a causal relationship between playing video games and enhanced cognitive ability. Video game training thus represents no exception to the general difficulty of obtaining far transfer. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Meta-Analytic Big Bang

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Shadish, William R.; Lecy, Jesse D.

2015-01-01

This article looks at the impact of meta-analysis and then explores why meta-analysis was developed at the time and by the scholars it did in the social sciences in the 1970s. For the first problem, impact, it examines the impact of meta-analysis using citation network analysis. The impact is seen in the sciences, arts and humanities, and on such…

Hemispheric specialization and creative thinking: a meta-analytic review of lateralization of creativity

NARCIS (Netherlands)

Mihov, K.M.; Denzler, M.; Förster, J.

2010-01-01

In the last two decades research on the neurophysiological processes of creativity has found contradicting results. Whereas most research suggests right hemisphere dominance in creative thinking, left-hemisphere dominance has also been reported. The present research is a meta-analytic review of the

The meta-analytic big bang.

Science.gov (United States)

Shadish, William R; Lecy, Jesse D

2015-09-01

This article looks at the impact of meta-analysis and then explores why meta-analysis was developed at the time and by the scholars it did in the social sciences in the 1970s. For the first problem, impact, it examines the impact of meta-analysis using citation network analysis. The impact is seen in the sciences, arts and humanities, and on such contemporaneous developments as multilevel modeling, medical statistics, qualitative methods, program evaluation, and single-case design. Using a constrained snowball sample of citations, we highlight key articles that are either most highly cited or most central to the systematic review network. Then, the article examines why meta-analysis came to be in the 1970s in the social sciences through the work of Gene Glass, Robert Rosenthal, and Frank Schmidt, each of whom developed similar theories of meta-analysis at about the same time. The article ends by explaining how Simonton's chance configuration theory and Campbell's evolutionary epistemology can illuminate why meta-analysis occurred with these scholars when it did and not in medical sciences. Copyright © 2015 John Wiley & Sons, Ltd.

Who benefits from supported employment: a meta-analytic study.

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Campbell, Kikuko

2012-02-01

AIMS: This meta-analysis sought to identify which subgroups of clients with severe mental illness (SMI) benefited from evidence-based supported employment. METHODS: We used meta-analysis to pool the samples from 4 randomized controlled trials comparing the Individual Placement and Support (IPS) model of supported employment to well-regarded vocational approaches using stepwise models and brokered services. Meta-analysis was used to determine the magnitude of effects for IPS\\/control group differences within specific client subgroups (defined by 2 work history, 7 sociodemographic, and 8 clinical variables) on 3 competitive employment outcomes (obtaining a job, total weeks worked, and job tenure). RESULTS: The findings strongly favored IPS, with large effect sizes across all outcomes: 0.96 for job acquisition, 0.79 for total weeks worked, and 0.74 for job tenure. Overall, 90 (77%) of the 117 effect sizes calculated for the 39 subgroups exceeded 0.70, and all 117 favored IPS. CONCLUSIONS: IPS produces better competitive employment outcomes for persons with SMI than alternative vocational programs regardless of background demographic, clinical, and employment characteristics.

Promoting retention of nurses: A meta-analytic examination of causes of nurse turnover.

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Nei, Darin; Snyder, Lori Anderson; Litwiller, Brett J

2015-01-01

Because the health care field is expected to be the fastest growing job field until 2020, an urgent need to focus on nurse retention exists. The aim of this study was to examine the relationships between predictors of turnover (i.e., personal characteristics, role states, job characteristics, group/leader relations, organizational/environmental perceptions, attitudinal reactions) and turnover cognitions and intentions, as well as actual turnover among nurses, in an effort to determine the strongest predictors of voluntary turnover. Meta-analysis was used to determine best estimates of the effect of predictors on turnover based on 106 primary studies of employed nurses. Meta-analyzed correlations were subjected to path analysis to establish the structural relationships among the study variables. Supportive and communicative leadership, network centrality, and organizational commitment are the strongest predictors of voluntary turnover based on meta-analytic correlations. Additional variables that relate to nurse turnover intentions include job strain, role tension, work-family conflict, job control, job complexity, rewards/recognition, and team cohesion. The findings suggest that some factors, such as salary, are relatively less important in prediction of turnover. Administrators concerned about nurse turnover may more effectively direct resources toward altering certain job characteristics and work conditions in the effort to reduce voluntary turnover among nurses.

Are K-12 Learners Motivated in Physical Education? A Meta-Analysis

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Chen, Senlin; Chen, Ang; Zhu, Xihe

2012-01-01

Previous studies devoted to K-12 learner motivation in physical education share a general assumption that students may lack motivation. This meta-analytic study examined published original studies (n = 79) to determine students' motivation level and the association between motivation and outcomes. Original means of motivation measures were…

Using meta-analytic path analysis to test theoretical predictions in health behavior: An illustration based on meta-analyses of the theory of planned behavior

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Hagger, Martin; Chan, Dervin K. C.; Protogerou, Cleo; Chatzisarantis, Nikos L. D.

2016-01-01

Objective Synthesizing research on social cognitive theories applied to health behavior is an important step in the development of an evidence base of psychological factors as targets for effective behavioral interventions. However, few meta-analyses of research on social cognitive theories in health contexts have conducted simultaneous tests of theoretically-stipulated pattern effects using path analysis. We argue that conducting path analyses of meta-analytic effects among constructs fr...

Hemispheric Specialization and Creative Thinking: A Meta-Analytic Review of Lateralization of Creativity

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Mihov, Konstantin M.; Denzler, Markus; Forster, Jens

2010-01-01

In the last two decades research on the neurophysiological processes of creativity has found contradicting results. Whereas most research suggests right hemisphere dominance in creative thinking, left-hemisphere dominance has also been reported. The present research is a meta-analytic review of the literature to establish how creative thinking…

Social Cognitive Career Theory, Conscientiousness, and Work Performance: A Meta-Analytic Path Analysis

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Brown, Steven D.; Lent, Robert W.; Telander, Kyle; Tramayne, Selena

2011-01-01

We performed a meta-analytic path analysis of an abbreviated version of social cognitive career theory's (SCCT) model of work performance (Lent, Brown, & Hackett, 1994). The model we tested included the central cognitive predictors of performance (ability, self-efficacy, performance goals), with the exception of outcome expectations. Results…

Recognition of Emotions in Autism: A Formal Meta-Analysis

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Uljarevic, Mirko; Hamilton, Antonia

2013-01-01

Determining the integrity of emotion recognition in autistic spectrum disorder is important to our theoretical understanding of autism and to teaching social skills. Previous studies have reported both positive and negative results. Here, we take a formal meta-analytic approach, bringing together data from 48 papers testing over 980 participants…

Comparing bona fide psychotherapies of depression in adults with two meta-analytical approaches.

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Sarah R Braun

Full Text Available OBJECTIVE: Despite numerous investigations, the question whether all bona fide treatments of depression are equally efficacious in adults has not been sufficiently answered. METHOD: We applied two different meta-analytical techniques (conventional meta-analysis and mixed treatment comparisons. Overall, 53 studies with 3,965 patients, which directly compared two or more bona fide psychotherapies in a randomized trial, were included. Meta-analyses were conducted regarding five different types of outcome measures. Additionally, the influence of possible moderators was examined. RESULTS: Direct comparisons of cognitive behavior therapy, behavior activation therapy, psychodynamic therapy, interpersonal therapy, and supportive therapies versus all other respective treatments indicated that at the end of treatment all treatments but supportive therapies were equally efficacious whereas there was some evidence that supportive therapies were somewhat less efficacious than all other treatments according to patient self-ratings and clinical significance. At follow-up no significant differences were present. Age, gender, comorbid mental disorders, and length of therapy session were found to moderate efficacy. Cognitive behavior therapy was superior in studies where therapy sessions lasted 90 minutes or longer, behavior activation therapy was more efficacious when therapy sessions lasted less than 90 minutes. Mixed treatment comparisons indicated no statistically significant differences in treatment efficacy but some interesting trends. CONCLUSIONS: This study suggests that there might be differential effects of bona fide psychotherapies which should be examined in detail.

Meta-analytic structural equation modelling

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Jak, Suzanne

2015-01-01

This book explains how to employ MASEM, the combination of meta-analysis (MA) and structural equation modelling (SEM). It shows how by using MASEM, a single model can be tested to explain the relationships between a set of variables in several studies. This book gives an introduction to MASEM, with a focus on the state of the art approach: the two stage approach of Cheung and Cheung & Chan. Both, the fixed and the random approach to MASEM are illustrated with two applications to real data. All steps that have to be taken to perform the analyses are discussed extensively. All data and syntax files are available online, so that readers can imitate all analyses. By using SEM for meta-analysis, this book shows how to benefit from all available information from all available studies, even if few or none of the studies report about all relationships that feature in the full model of interest.

Communication attitudes in children who stutter: A meta-analytic review.

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Guttormsen, Linn Stokke; Kefalianos, Elaina; Næss, Kari-Anne B

2015-12-01

This article presents a meta-analytic review of differences in communication attitudes between children who stutter (CWS) and children who do not stutter (CWNS). To be included in this review, the studies had to include a group of CWS and CWNS between the ages of 3-18 years and a measurement of communication attitudes. The journal articles were identified by using the key words stutter*, speech disfluenc*, fluency disorder*, and stammer* cross-referenced to awareness*, reaction*, attitude*, KiddyCAT, CAT, A-19 Scale, PASS and OASES. A total of 18 studies met the inclusion criteria for this meta-analysis. The results showed that CWS exhibit more negative communication attitudes than CWNS from the preschool years. The differences between the groups increased with age, but were not influenced by gender. The results indicate that negative communication attitudes can be an effect of stuttering. Key issues requiring further investigation are whether communication attitudes differ as a function of age at stuttering onset and whether communication attitudes influence the development of stuttering. After reading this article, the reader will be able to: (a) summarise empirical findings with regard to the relationship between communication attitudes and childhood stuttering; (b) describe the different instruments used to measure communication attitudes; (c) discuss the relationship between communication attitudes, age and gender. Copyright © 2015 Elsevier Inc. All rights reserved.

Proposal of a social alliance success model from a relationship marketing perspective: A meta-analytical study of the theoretical foundations

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María Jesús Barroso-Méndez

2015-07-01

Full Text Available Partnerships between businesses and non-governmental organizations (NGOs have become widely adopted mechanisms for collaboration in addressing complex social issues, the aim being to take advantage of the two types of organizational rationale to generate mutual value. Many such alliances have proved to be unsuccessful, however. To assist managers improve the likelihood of success of their collaborative relationships, the authors propose a success model of business-NGO partnering processes based on Relationship Marketing Theory. They also analyse the theoretical bases of the model's hypotheses through a meta-analytical study of the existing literature.

Different presence of Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, and Toxoplasma gondii in schizophrenia: meta-analysis and analytical study

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Gutiérrez-Fernández J

2015-03-01

Full Text Available José Gutiérrez-Fernández,1 Juan de Dios Luna del Castillo,2 Sara Mañanes-González,1 José Antonio Carrillo-Ávila,1 Blanca Gutiérrez,3 Jorge A Cervilla,3 Antonio Sorlózano-Puerto1 1Department of Microbiology, 2Department of Statistics and Operation Research, 3Department of Psychiatry, Institute of Neurosciences and CIBERSAM, School of Medicine and Biohealth Research Institute (Instituto de Investigación Biosanitaria IBS-Granada, University of Granada, Granada, Spain Abstract: In the present study we have performed both a meta-analysis and an analytical study exploring the presence of Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, and Toxoplasma gondii antibodies in a sample of 143 schizophrenic patients and 143 control subjects. The meta-analysis was performed on papers published up to April 2014. The presence of serum immunoglobulin G and immunoglobulin A was performed by enzyme-linked immunosorbent assay test. The detection of microbial DNA in total peripheral blood was performed by nested polymerase chain reaction. The meta-analysis showed that: 1 C. pneumoniae DNA in blood and brain are more common in schizophrenic patients; 2 there is association with parasitism by T. gondii, despite the existence of publication bias; and 3 herpes viruses were not more common in schizophrenic patients. In our sample only anti-Toxoplasma immunoglobulin G was more prevalent and may be a risk factor related to schizophrenia, with potential value for prevention. Keywords: meta-analysis, analytical study, Chlamydia pneumoniae, herpes simplex virus type 1, human herpes virus 6, Toxoplasma gondii, schizophrenia

The Relationship between Spirituality and Religiosity on Psychological Outcomes in Adolescents and Emerging Adults: A Meta-Analytic Review

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Yonker, Julie E.; Schnabelrauch, Chelsea A.; DeHaan, Laura G.

2012-01-01

The present study used meta-analytic techniques to examine the association between spirituality and religiosity (S/R) and psychological outcomes in adolescents and emerging adults. The outcome measures of risk behavior, depression, well-being, self-esteem, and personality were examined with respect to the influence of S/R across 75 independent…

A framework for the meta-analysis of Bland-Altman studies based on a limits of agreement approach.

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Tipton, Elizabeth; Shuster, Jonathan

2017-10-15

Bland-Altman method comparison studies are common in the medical sciences and are used to compare a new measure to a gold-standard (often costlier or more invasive) measure. The distribution of these differences is summarized by two statistics, the 'bias' and standard deviation, and these measures are combined to provide estimates of the limits of agreement (LoA). When these LoA are within the bounds of clinically insignificant differences, the new non-invasive measure is preferred. Very often, multiple Bland-Altman studies have been conducted comparing the same two measures, and random-effects meta-analysis provides a means to pool these estimates. We provide a framework for the meta-analysis of Bland-Altman studies, including methods for estimating the LoA and measures of uncertainty (i.e., confidence intervals). Importantly, these LoA are likely to be wider than those typically reported in Bland-Altman meta-analyses. Frequently, Bland-Altman studies report results based on repeated measures designs but do not properly adjust for this design in the analysis. Meta-analyses of Bland-Altman studies frequently exclude these studies for this reason. We provide a meta-analytic approach that allows inclusion of estimates from these studies. This includes adjustments to the estimate of the standard deviation and a method for pooling the estimates based upon robust variance estimation. An example is included based on a previously published meta-analysis. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

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

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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.

A case study of discordant overlapping meta-analyses: vitamin d supplements and fracture.

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Mark J Bolland

Full Text Available BACKGROUND: Overlapping meta-analyses on the same topic are now very common, and discordant results often occur. To explore why discordant results arise, we examined a common topic for overlapping meta-analyses- vitamin D supplements and fracture. METHODS AND FINDINGS: We identified 24 meta-analyses of vitamin D (with or without calcium and fracture in a PubMed search in October 2013, and analysed a sample of 7 meta-analyses in the highest ranking general medicine journals. We used the AMSTAR tool to assess the quality of the meta-analyses, and compared their methodologies, analytic techniques and results. Applying the AMSTAR tool suggested the meta-analyses were generally of high quality. Despite this, there were important differences in trial selection, data extraction, and analytical methods that were only apparent after detailed assessment. 25 trials were included in at least one meta-analysis. Four meta-analyses included all eligible trials according to the stated inclusion and exclusion criteria, but the other 3 meta-analyses "missed" between 3 and 8 trials, and 2 meta-analyses included apparently ineligible trials. The relative risks used for individual trials differed between meta-analyses for total fracture in 10 of 15 trials, and for hip fracture in 6 of 12 trials, because of different outcome definitions and analytic approaches. The majority of differences (11/16 led to more favourable estimates of vitamin D efficacy compared to estimates derived from unadjusted intention-to-treat analyses using all randomised participants. The conclusions of the meta-analyses were discordant, ranging from strong statements that vitamin D prevents fractures to equally strong statements that vitamin D without calcium does not prevent fractures. CONCLUSIONS: Substantial differences in trial selection, outcome definition and analytic methods between overlapping meta-analyses led to discordant estimates of the efficacy of vitamin D for fracture prevention

Meta-Study as Diagnostic: Toward Content Over Form in Qualitative Synthesis.

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Frost, Julia; Garside, Ruth; Cooper, Chris; Britten, Nicky

2016-02-01

Having previously conducted qualitative syntheses of the diabetes literature, we wanted to explore the changes in theoretical approaches, methodological practices, and the construction of substantive knowledge which have recently been presented in the qualitative diabetes literature. The aim of this research was to explore the feasibility of synthesizing existing qualitative syntheses of patient perspectives of diabetes using meta-study methodology. A systematic review of qualitative literature, published between 2000 and 2013, was conducted. Six articles were identified as qualitative syntheses. The meta-study methodology was used to compare the theoretical, methodological, analytic, and synthetic processes across the six studies, exploring the potential for an overarching synthesis. We identified that while research questions have increasingly concentrated on specific aspects of diabetes, the focus on systematic review processes has led to the neglect of qualitative theory and methods. This can inhibit the production of compelling results with meaningful clinical applications. Although unable to produce a synthesis of syntheses, we recommend that researchers who conduct qualitative syntheses pay equal attention to qualitative traditions and systematic review processes, to produce research products that are both credible and applicable. © The Author(s) 2015.

Perceived Discrimination and Health: A Meta-Analytic Review

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Pascoe, Elizabeth A.; Richman, Laura Smart

2009-01-01

Perceived discrimination has been studied with regard to its impact on several types of health effects. This meta-analysis provides a comprehensive account of the relationships between multiple forms of perceived discrimination and both mental and physical health outcomes. In addition, this meta-analysis examines potential mechanisms by which…

Heavy metal phytoremediation from a meta-analytical perspective

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Audet, Patrick [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie St., Ottawa, Ont. K1N 6N5 (Canada)]. E-mail: paude086@uottawa.ca; Charest, Christiane [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie St., Ottawa, Ont. K1N 6N5 (Canada)]. E-mail: ccharest@science.uottawa.ca

2007-05-15

We conducted a literature survey and correlated heavy metal (HM) uptake and plant growth factors from published data to estimate the effectiveness of phytoextraction. The indicators of the actual plant HM uptake showed positive correlations with soil-HM concentrations, while the relative plant HM uptake showed negative correlations. Plant growth was negatively correlated with both the plant and soil-HM concentrations. These significant relationships were found for the majority of HM tested (e.g. Zn, Cd, Pb, Cu, Cr, and Fe) with a few exceptions (e.g. Ni, Co, and Mn). After fitting the correlation coefficients, the highest proportion of variance among the studies was mainly due to the experimental parameters or the plant species. When the metabolic costs of HM uptake are taken into account, the phytoextraction appears to be less effective beyond critical HM concentrations. Despite these constraints, it is emphasized that HM phytoextraction can play an important role in bioremediation. - This meta-analytical approach has revealed a compromise between growth and HM uptake when plants are subjected to toxic soil-HM levels.

Heavy metal phytoremediation from a meta-analytical perspective

International Nuclear Information System (INIS)

Audet, Patrick; Charest, Christiane

2007-01-01

We conducted a literature survey and correlated heavy metal (HM) uptake and plant growth factors from published data to estimate the effectiveness of phytoextraction. The indicators of the actual plant HM uptake showed positive correlations with soil-HM concentrations, while the relative plant HM uptake showed negative correlations. Plant growth was negatively correlated with both the plant and soil-HM concentrations. These significant relationships were found for the majority of HM tested (e.g. Zn, Cd, Pb, Cu, Cr, and Fe) with a few exceptions (e.g. Ni, Co, and Mn). After fitting the correlation coefficients, the highest proportion of variance among the studies was mainly due to the experimental parameters or the plant species. When the metabolic costs of HM uptake are taken into account, the phytoextraction appears to be less effective beyond critical HM concentrations. Despite these constraints, it is emphasized that HM phytoextraction can play an important role in bioremediation. - This meta-analytical approach has revealed a compromise between growth and HM uptake when plants are subjected to toxic soil-HM levels

Toward an integrative theory of training motivation: a meta-analytic path analysis of 20 years of research.

Science.gov (United States)

Colquitt, J A; LePine, J A; Noe, R A

2000-10-01

This article meta-analytically summarizes the literature on training motivation, its antecedents, and its relationships with training outcomes such as declarative knowledge, skill acquisition, and transfer. Significant predictors of training motivation and outcomes included individual characteristics (e.g., locus of control, conscientiousness, anxiety, age, cognitive ability, self-efficacy, valence, job involvement) and situational characteristics (e.g., climate). Moreover, training motivation explained incremental variance in training outcomes beyond the effects of cognitive ability. Meta-analytic path analyses further showed that the effects of personality, climate, and age on training outcomes were only partially mediated by self-efficacy, valence, and job involvement. These findings are discussed in terms of their practical significance and their implications for an integrative theory of training motivation.

A Two-Stage Approach to Synthesizing Covariance Matrices in Meta-Analytic Structural Equation Modeling

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Cheung, Mike W. L.; Chan, Wai

2009-01-01

Structural equation modeling (SEM) is widely used as a statistical framework to test complex models in behavioral and social sciences. When the number of publications increases, there is a need to systematically synthesize them. Methodology of synthesizing findings in the context of SEM is known as meta-analytic SEM (MASEM). Although correlation…

Positive psychology interventions: A meta-analysis of randomized controlled studies

NARCIS (Netherlands)

Bolier, Linda; Haverman, M.; Westerhof, Gerben Johan; Riper, H.; Smit, F.; Bohlmeijer, Ernst Thomas

2013-01-01

Background The use of positive psychological interventions may be considered as a complementary strategy in mental health promotion and treatment. The present article constitutes a meta-analytical study of the effectiveness of positive psychology interventions for the general public and for

Positive psychology interventions: a meta-analysis of randomized controlled studies

NARCIS (Netherlands)

Bolier, L.; Haverman, M.; Westerhof, G.J.; Riper, H.; Smit, H.F.E.; Bohlmeijer, E.

2013-01-01

Background: The use of positive psychological interventions may be considered as a complementary strategy in mental health promotion and treatment. The present article constitutes a meta-analytical study of the effectiveness of positive psychology interventions for the general public and for

The Efficacy of Violence Prediction: A Meta-Analytic Comparison of Nine Risk Assessment Tools

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Yang, Min; Wong, Stephen C. P.; Coid, Jeremy

2010-01-01

Actuarial risk assessment tools are used extensively to predict future violence, but previous studies comparing their predictive accuracies have produced inconsistent findings as a result of various methodological issues. We conducted meta-analyses of the effect sizes of 9 commonly used risk assessment tools and their subscales to compare their…

A meta-analytic review of experiments examining the effects of extrinsic rewards on intrinsic motivation.

Science.gov (United States)

Deci, E L; Koestner, R; Ryan, R M

1999-11-01

A meta-analysis of 128 studies examined the effects of extrinsic rewards on intrinsic motivation. As predicted, engagement-contingent, completion-contingent, and performance-contingent rewards significantly undermined free-choice intrinsic motivation (d = -0.40, -0.36, and -0.28, respectively), as did all rewards, all tangible rewards, and all expected rewards. Engagement-contingent and completion-contingent rewards also significantly undermined self-reported interest (d = -0.15, and -0.17), as did all tangible rewards and all expected rewards. Positive feedback enhanced both free-choice behavior (d = 0.33) and self-reported interest (d = 0.31). Tangible rewards tended to be more detrimental for children than college students, and verbal rewards tended to be less enhancing for children than college students. The authors review 4 previous meta-analyses of this literature and detail how this study's methods, analyses, and results differed from the previous ones.

Stability and change of personality traits, self-esteem, and well-being: Introducing the meta-analytic stability and change model of retest correlations.

Science.gov (United States)

Anusic, Ivana; Schimmack, Ulrich

2016-05-01

The stability of individual differences is a fundamental issue in personality psychology. Although accumulating evidence suggests that many psychological attributes are both stable and change over time, existing research rarely takes advantage of theoretical models that capture both stability and change. In this article, we present the Meta-Analytic Stability and Change model (MASC), a novel meta-analytic model for synthesizing data from longitudinal studies. MASC is based on trait-state models that can separate influences of stable and changing factors from unreliable variance (Kenny & Zautra, 1995). We used MASC to evaluate the extent to which personality traits, life satisfaction, affect, and self-esteem are influenced by these different factors. The results showed that the majority of reliable variance in personality traits is attributable to stable influences (83%). Changing factors had a greater influence on reliable variance in life satisfaction, self-esteem, and affect than in personality (42%-56% vs. 17%). In addition, changing influences on well-being were more stable than changing influences on personality traits, suggesting that different changing factors contribute to personality and well-being. Measures of affect were less reliable than measures of the other 3 constructs, reflecting influences of transient factors, such as mood on affective judgments. After accounting for differences in reliability, stability of affect did not differ from other well-being variables. Consistent with previous research, we found that stability of individual differences increases with age. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Meta-analytic Review of Memory Impairment in Behavioral Variant Frontotemporal Dementia.

Science.gov (United States)

Poos, Jackie M; Jiskoot, Lize C; Papma, Janne M; van Swieten, John C; van den Berg, Esther

2018-03-19

A meta-analysis of the extent, nature and pattern of memory performance in behavioral variant frontotemporal dementia (bvFTD). Multiple observational studies have challenged the relative sparing of memory in bvFTD as stated in the current diagnostic criteria. We performed a meta-analytic review covering the period 1967 to February 2017 of case-control studies on episodic memory in bvFTD versus control participants (16 studies, 383 patients, 603 control participants), and patients with bvFTD versus those with Alzheimer's disease (AD) (20 studies, 452 bvFTD, 874 AD). Differences between both verbal and non-verbal working memory, episodic memory learning and recall, and recognition memory were examined. Data were extracted from the papers and combined into a common metric measure of effect, Hedges' d. Patients with bvFTD show large deficits in memory performance compared to controls (Hedges' d -1.10; 95% confidence interval [CI] [-1.23, -0.95]), but perform significantly better than patients with AD (Hedges' d 0.85; 95% CI [0.69, 1.03]). Learning and recall tests differentiate best between patients with bvFTD and AD (p<.01). There is 37-62% overlap in test scores between the two groups. This study points to memory disorders in patients with bvFTD, with performance at an intermediate level between controls and patients with AD. This indicates that, instead of being an exclusion criterion for bvFTD diagnosis, memory deficits should be regarded as a potential integral part of the clinical spectrum. (JINS, 2018, 24, 1-13).

Multivariate Meta-Analysis of Genetic Association Studies: A Simulation Study.

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Binod Neupane

Full Text Available In a meta-analysis with multiple end points of interests that are correlated between or within studies, multivariate approach to meta-analysis has a potential to produce more precise estimates of effects by exploiting the correlation structure between end points. However, under random-effects assumption the multivariate estimation is more complex (as it involves estimation of more parameters simultaneously than univariate estimation, and sometimes can produce unrealistic parameter estimates. Usefulness of multivariate approach to meta-analysis of the effects of a genetic variant on two or more correlated traits is not well understood in the area of genetic association studies. In such studies, genetic variants are expected to roughly maintain Hardy-Weinberg equilibrium within studies, and also their effects on complex traits are generally very small to modest and could be heterogeneous across studies for genuine reasons. We carried out extensive simulation to explore the comparative performance of multivariate approach with most commonly used univariate inverse-variance weighted approach under random-effects assumption in various realistic meta-analytic scenarios of genetic association studies of correlated end points. We evaluated the performance with respect to relative mean bias percentage, and root mean square error (RMSE of the estimate and coverage probability of corresponding 95% confidence interval of the effect for each end point. Our simulation results suggest that multivariate approach performs similarly or better than univariate method when correlations between end points within or between studies are at least moderate and between-study variation is similar or larger than average within-study variation for meta-analyses of 10 or more genetic studies. Multivariate approach produces estimates with smaller bias and RMSE especially for the end point that has randomly or informatively missing summary data in some individual studies, when

A meta-analytic review on treatment dropout in child and adolescent outpatient mental health care

NARCIS (Netherlands)

de Haan, A.M.; Boon, A.E.; de Jong, J.T.V.M.; Hoeve, M.; Vermeiren, R.R.J.M.

2013-01-01

A large proportion (28% up to 75%) of the treatments in youth mental health care results in premature termination (dropout). It is important to gain knowledge of the determinants of dropout because it can have very severe consequences. The aim of our meta-analytic review was to provide an overview

Eye movement dysfunction in first-degree relatives of patients with schizophrenia: a meta-analytic evaluation of candidate endophenotypes.

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Calkins, Monica E; Iacono, William G; Ones, Deniz S

2008-12-01

Several forms of eye movement dysfunction (EMD) are regarded as promising candidate endophenotypes of schizophrenia. Discrepancies in individual study results have led to inconsistent conclusions regarding particular aspects of EMD in relatives of schizophrenia patients. To quantitatively evaluate and compare the candidacy of smooth pursuit, saccade and fixation deficits in first-degree biological relatives, we conducted a set of meta-analytic investigations. Among 18 measures of EMD, memory-guided saccade accuracy and error rate, global smooth pursuit dysfunction, intrusive saccades during fixation, antisaccade error rate and smooth pursuit closed-loop gain emerged as best differentiating relatives from controls (standardized mean differences ranged from .46 to .66), with no significant differences among these measures. Anticipatory saccades, but no other smooth pursuit component measures were also increased in relatives. Visually-guided reflexive saccades were largely normal. Moderator analyses examining design characteristics revealed few variables affecting the magnitude of the meta-analytically observed effects. Moderate effect sizes of relatives v. controls in selective aspects of EMD supports their endophenotype potential. Future work should focus on facilitating endophenotype utility through attention to heterogeneity of EMD performance, relationships among forms of EMD, and application in molecular genetics studies.

Meta-media and meta-communication - Revisiting the concept of genre in the digital media environment

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Klaus Bruhn Jensen

2011-08-01

Full Text Available As analytical categories, genres have traditionally occupied a middle ground – between media as technologies and institutions, on the one hand, and discourses as material and modal forms of expression and interaction, on the other. With digitalization, the very concept of genre is in doubt: is the world wide web, Facebook, or the writing on its walls the genre? This article situat es genre in relation to the concepts of meta-media and meta-communication. First, I characterize the computer and the internet as metamedia, incorporating previous genres of embodied communication as well as mass communication. Second, I describe genres as a variety of meta-communication, which serves to configure communication in the first place. In conclusion, I discuss whether and how a category of meta-genres might help to account for some distinctive features of the digital media environment.

Understanding suicide risk within the Research Domain Criteria (RDoC) framework: A meta-analytic review.

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Glenn, Catherine R; Kleiman, Evan M; Cha, Christine B; Deming, Charlene A; Franklin, Joseph C; Nock, Matthew K

2018-01-01

The field is in need of novel and transdiagnostic risk factors for suicide. The National Institute of Mental Health's Research Domain Criteria (RDoC) provides a framework that may help advance research on suicidal behavior. We conducted a meta-analytic review of existing prospective risk and protective factors for suicidal thoughts and behaviors (ideation, attempts, and deaths) that fall within one of the five RDoC domains or relate to a prominent suicide theory. Predictors were selected from a database of 4,082 prospective risk and protective factors for suicide outcomes. A total of 460 predictors met inclusion criteria for this meta-analytic review and most examined risk (vs. protective) factors for suicidal thoughts and behaviors. The overall effect of risk factors was statistically significant, but relatively small, in predicting suicide ideation (weighted mean odds ratio: wOR = 1.72; 95% CI: 1.59-1.87), suicide attempt (wOR = 1.66 [1.57-1.76), and suicide death (wOR = 1.41 [1.24-1.60]). Across all suicide outcomes, most risk factors related to the Negative Valence Systems domain, although effect sizes were of similar magnitude across RDoC domains. This study demonstrated that the RDoC framework provides a novel and promising approach to suicide research; however, relatively few studies of suicidal behavior fit within this framework. Future studies must go beyond the "usual suspects" of suicide risk factors (e.g., mental disorders, sociodemographics) to understand the processes that combine to lead to this deadly outcome. © 2017 Wiley Periodicals, Inc.

Organizational Culture and Organizational Effectiveness: A Meta-Analytic Investigation of the Competing Values Framework's Theoretical Suppositions

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Hartnell, Chad A.; Ou, Amy Yi; Kinicki, Angelo

2011-01-01

We apply Quinn and Rohrbaugh's (1983) competing values framework (CVF) as an organizing taxonomy to meta-analytically test hypotheses about the relationship between 3 culture types and 3 major indices of organizational effectiveness (employee attitudes, operational performance [i.e., innovation and product and service quality], and financial…

The reasonable woman standard: a meta-analytic review of gender differences in perceptions of sexual harassment.

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Blumenthal, J A

1998-02-01

Courts and legislatures have begun to develop the "reasonable woman standard" (RWS) as a criterion for deciding sexual harassment trials. This standard rests on assumptions of a "wide divergence" between the perceptions of men and women when viewing social-sexual behavior that may be considered harassing. Narrative reviews of the literature on such perceptions have suggested that these assumptions are only minimally supported. To test these assumptions quantitatively, a meta-analytic review was conducted that assessed the size, stability, and moderators of gender differences in perceptions of sexual harassment. The effect of the actor's status relative to the target also was evaluated meta-analytically, as one alternative to the importance of gender effects. Results supported the claims of narrative reviews for a relatively small gender effect, and draw attention to the status effect. In discussing legal implications of the present findings, earlier claims are echoed suggesting caution in establishing the reasonable woman standard, and one alternative to the RWS, the "reasonable victim standard," is discussed.

The Efficacy of Mindfulness-Based Interventions in Primary Care: A Meta-Analytic Review.

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Demarzo, Marcelo M P; Montero-Marin, Jesús; Cuijpers, Pim; Zabaleta-del-Olmo, Edurne; Mahtani, Kamal R; Vellinga, Akke; Vicens, Caterina; López-del-Hoyo, Yolanda; García-Campayo, Javier

2015-11-01

Positive effects have been reported after mindfulness-based interventions (MBIs) in diverse clinical and nonclinical populations. Primary care is a key health care setting for addressing common chronic conditions, and an effective MBI designed for this setting could benefit countless people worldwide. Meta-analyses of MBIs have become popular, but little is known about their efficacy in primary care. Our aim was to investigate the application and efficacy of MBIs that address primary care patients. We performed a meta-analytic review of randomized controlled trials addressing the effect of MBIs in adult patients recruited from primary care settings. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and Cochrane guidelines were followed. Effect sizes were calculated with the Hedges g in random effects models. The meta-analyses were based on 6 trials having a total of 553 patients. The overall effect size of MBI compared with a control condition for improving general health was moderate (g = 0.48; P = .002), with moderate heterogeneity (I(2) = 59; P .05). Although the number of randomized controlled trials applying MBIs in primary care is still limited, our results suggest that these interventions are promising for the mental health and quality of life of primary care patients. We discuss innovative approaches for implementing MBIs, such as complex intervention and stepped care. © 2015 Annals of Family Medicine, Inc.

Social relationships and mortality risk: a meta-analytic review.

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Holt-Lunstad, Julianne; Smith, Timothy B; Layton, J Bradley

2010-07-27

The quality and quantity of individuals' social relationships has been linked not only to mental health but also to both morbidity and mortality. This meta-analytic review was conducted to determine the extent to which social relationships influence risk for mortality, which aspects of social relationships are most highly predictive, and which factors may moderate the risk. Data were extracted on several participant characteristics, including cause of mortality, initial health status, and pre-existing health conditions, as well as on study characteristics, including length of follow-up and type of assessment of social relationships. Across 148 studies (308,849 participants), the random effects weighted average effect size was OR = 1.50 (95% CI 1.42 to 1.59), indicating a 50% increased likelihood of survival for participants with stronger social relationships. This finding remained consistent across age, sex, initial health status, cause of death, and follow-up period. Significant differences were found across the type of social measurement evaluated (psocial relationships on risk for mortality is comparable with well-established risk factors for mortality. Please see later in the article for the Editors' Summary.

Ethical leadership: meta-analytic evidence of criterion-related and incremental validity.

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Ng, Thomas W H; Feldman, Daniel C

2015-05-01

This study examines the criterion-related and incremental validity of ethical leadership (EL) with meta-analytic data. Across 101 samples published over the last 15 years (N = 29,620), we observed that EL demonstrated acceptable criterion-related validity with variables that tap followers' job attitudes, job performance, and evaluations of their leaders. Further, followers' trust in the leader mediated the relationships of EL with job attitudes and performance. In terms of incremental validity, we found that EL significantly, albeit weakly in some cases, predicted task performance, citizenship behavior, and counterproductive work behavior-even after controlling for the effects of such variables as transformational leadership, use of contingent rewards, management by exception, interactional fairness, and destructive leadership. The article concludes with a discussion of ways to strengthen the incremental validity of EL. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Meta-Analysis of Coefficient Alpha

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Rodriguez, Michael C.; Maeda, Yukiko

2006-01-01

The meta-analysis of coefficient alpha across many studies is becoming more common in psychology by a methodology labeled reliability generalization. Existing reliability generalization studies have not used the sampling distribution of coefficient alpha for precision weighting and other common meta-analytic procedures. A framework is provided for…

Transformational Leadership and Organizational Citizenship Behavior: A Meta-Analytic Test of Underlying Mechanisms.

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Nohe, Christoph; Hertel, Guido

2017-01-01

Based on social exchange theory, we examined and contrasted attitudinal mediators (affective organizational commitment, job satisfaction) and relational mediators (trust in leader, leader-member exchange; LMX) of the positive relationship between transformational leadership and organizational citizenship behavior (OCB). Hypotheses were tested using meta-analytic path models with correlations from published meta-analyses (761 samples with 227,419 individuals overall). When testing single-mediator models, results supported our expectations that each of the mediators explained the relationship between transformational leadership and OCB. When testing a multi-mediator model, LMX was the strongest mediator. When testing a model with a latent attitudinal mechanism and a latent relational mechanism, the relational mechanism was the stronger mediator of the relationship between transformational leadership and OCB. Our findings help to better understand the underlying mechanisms of the relationship between transformational leadership and OCB.

The association between arithmetic and reading performance in school: A meta-analytic study.

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Singer, Vivian; Strasser, Kathernie

2017-12-01

Many studies of school achievement find a significant association between reading and arithmetic achievement. The magnitude of the association varies widely across the studies, but the sources of this variation have not been identified. The purpose of this paper is to examine the magnitude and determinants of the relation between arithmetic and reading performance during elementary and middle school years. We meta-analyzed 210 correlations between math and reading measures, coming from 68 independent samples (the overall sample size was 58923 participants). The meta-analysis yielded an average correlation of 0.55 between math and reading measures. Among the moderators tested, only transparency of orthography and use of timed or untimed tests were significant in explaining the size of the correlation, with the largest correlations observed between timed measures of arithmetic and reading and between math and reading in opaque orthographies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Statistical Power in Meta-Analysis

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Liu, Jin

2015-01-01

Statistical power is important in a meta-analysis study, although few studies have examined the performance of simulated power in meta-analysis. The purpose of this study is to inform researchers about statistical power estimation on two sample mean difference test under different situations: (1) the discrepancy between the analytical power and…

Statistical methodology for estimating the mean difference in a meta-analysis without study-specific variance information.

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Sangnawakij, Patarawan; Böhning, Dankmar; Adams, Stephen; Stanton, Michael; Holling, Heinz

2017-04-30

Statistical inference for analyzing the results from several independent studies on the same quantity of interest has been investigated frequently in recent decades. Typically, any meta-analytic inference requires that the quantity of interest is available from each study together with an estimate of its variability. The current work is motivated by a meta-analysis on comparing two treatments (thoracoscopic and open) of congenital lung malformations in young children. Quantities of interest include continuous end-points such as length of operation or number of chest tube days. As studies only report mean values (and no standard errors or confidence intervals), the question arises how meta-analytic inference can be developed. We suggest two methods to estimate study-specific variances in such a meta-analysis, where only sample means and sample sizes are available in the treatment arms. A general likelihood ratio test is derived for testing equality of variances in two groups. By means of simulation studies, the bias and estimated standard error of the overall mean difference from both methodologies are evaluated and compared with two existing approaches: complete study analysis only and partial variance information. The performance of the test is evaluated in terms of type I error. Additionally, we illustrate these methods in the meta-analysis on comparing thoracoscopic and open surgery for congenital lung malformations and in a meta-analysis on the change in renal function after kidney donation. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Constraints on the nuclear equation of state from nuclear masses and radii in a Thomas-Fermi meta-modeling approach

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Chatterjee, D.; Gulminelli, F.; Raduta, Ad. R.; Margueron, J.

2017-12-01

The question of correlations among empirical equation of state (EoS) parameters constrained by nuclear observables is addressed in a Thomas-Fermi meta-modeling approach. A recently proposed meta-modeling for the nuclear EoS in nuclear matter is augmented with a single finite size term to produce a minimal unified EoS functional able to describe the smooth part of the nuclear ground state properties. This meta-model can reproduce the predictions of a large variety of models, and interpolate continuously between them. An analytical approximation to the full Thomas-Fermi integrals is further proposed giving a fully analytical meta-model for nuclear masses. The parameter space is sampled and filtered through the constraint of nuclear mass reproduction with Bayesian statistical tools. We show that this simple analytical meta-modeling has a predictive power on masses, radii, and skins comparable to full Hartree-Fock or extended Thomas-Fermi calculations with realistic energy functionals. The covariance analysis on the posterior distribution shows that no physical correlation is present between the different EoS parameters. Concerning nuclear observables, a strong correlation between the slope of the symmetry energy and the neutron skin is observed, in agreement with previous studies.

Empathic accuracy and relationship satisfaction: A meta-analytic review.

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Sened, Haran; Lavidor, Michal; Lazarus, Gal; Bar-Kalifa, Eran; Rafaeli, Eshkol; Ickes, William

2017-09-01

Empathic accuracy (EA; Ickes & Hodges, 2013) is the extent to which people accurately perceive their peers' thoughts, feelings, and other inner mental states. EA has particularly interested researchers in the context of romantic couples. Reviews of the literature suggest a possible link between romantic partners' EA and their relationship satisfaction (Ickes & Simpson, 2001; Sillars & Scott, 1983). To assess the magnitude of this association and examine possible moderators, we performed a meta-analytic review of 21 studies (total N = 2,739 participants) that examined the association between EA and satisfaction. We limited our review to studies measuring EA using the dyadic interaction paradigm (Ickes, Stinson, Bissonnette, & Garcia, 1990). We found a small but significant association between the two (r = .134, p .1). The association was also stronger in relationships of moderate length, suggesting that EA may be more meaningful when relationships are consolidating but before they become stable. Gender and procedural variations on the dyadic interaction paradigm did not moderate the association, and there was no difference depending on whether the association was between EA and perceivers' or targets' satisfaction (i.e., actor or partner effects). We discuss the implications of these findings and offer recommendations for future EA studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

A Meta-analytic Review of Religious or Spiritual Involvement and Social Health among Cancer Patients

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Sherman, Allen C; Merluzzi, Thomas V; Pustejovsky, James E; Park, Crystal L; George, Login; Fitchett, George; Jim, Heather SL; Munoz, Alexis R; Danhauer, Suzanne C; Snyder, Mallory A; Salsman, John M

2015-01-01

Background Religion and spirituality (R/S) play an important role in the daily lives of many cancer patients. There has been great interest in determining whether R/S factors are related to clinically-relevant health outcomes. This meta-analytic review examined associations between dimensions of R/S and social health (e.g., social roles and relationships). Methods A systematic search of PubMed, PsycInfo, Cochrane Library, and CINAHL databases was conducted, and data were extracted by four pairs of investigators. Bivariate associations between specific R/S dimensions and social health outcomes were examined in a meta-analysis using a generalized estimating equation (GEE) approach. Results A total of 78 independent samples encompassing 14,277 patients were included in the meta-analysis. Social health was significantly associated with overall R/S (Fisher z effect size = .20, Pcancer. Further research is needed to examine the temporal nature of these associations and the mechanisms that underlie them. PMID:26258730

Association between childhood trauma and accelerated telomere erosion in adulthood: A meta-analytic study.

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Li, Zongchang; He, Ying; Wang, Dong; Tang, Jingsong; Chen, Xiaogang

2017-10-01

Childhood trauma has long-term sequelae on health status and contributes to numbers of somatic and mental disorders in later life. Findings from experimental studies in animals suggest that telomere erosion may be a mediator of this relationship. However, results from human studies are heterogeneous. To address these inconsistencies, we performed a meta-analysis regarding the association between childhood trauma and telomere length in adulthood. Articles were identified by systematically searching the Medline, EMBASE and Web of Science databases. Twenty four studies, which include twenty six sample sets and 30,919 participants, met the inclusion criteria for meta-analyses. This meta-analyses revealed that individuals experienced childhood trauma have accelerated telomere erosion in adulthood, with a small effect size (r = -0.05, 95% CI = -0.08-0.03, p childhood trauma revealed a trend in difference between groups (Q = 5.24, p = 0.07). Analyses for individual trauma types revealed a significant association between childhood separation and telomere erosion (r = -0.09, p childhood trauma and accelerated telomere erosion in adulthood, and further revealed that different trauma types have various impacts on telomere. Additional research on the mechanism that links the individual types of childhood trauma with telomere is needed in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

Financial Determinants for Improving Public Sector Accountability: A Meta-Analytic Study

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Laura Alcaide MUÑOZ

2013-12-01

Full Text Available The economic crisis has highlighted the need to pay close attention to the disclosure of financial information by public administration institutions; this is an element contributing to the control, accountability and responsibility and thus to achieving greater financial stability and sustainability. Although the disclosure of public financial information has traditionally been linked with financial variables, previous researches in this respect have been somewhat inconsistent in their findings, and conclusive evidence has yet to be provided regarding these factors and their influence on the level of disclosure. The present meta-analysis tries to reveal the existence of a statistically significant association between certain financial variables and the disclosure of public financial information, although the strength and sign of this association will depend on the context under analysis. The results obtained indicate that, depending on the context in which public managers are operating, they may have different attitudes toward the disclosure of public financial information; the medium employed for the dissemination and public indebtedness are also significant factors to this disclosure. Therefore, results reveal a variable degree of predisposition among public managers to adopt policies aimed at increasing the disclosure of public financial information.

Formalizing the definition of meta-analysis in Molecular Ecology.

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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.

A Meta-Analysis of Advance-Organizer Studies.

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Stone, Carol Leth

Long term studies of advance organizers (AO) were analyzed with Glass's meta-analysis technique. AO's were defined as bridges from reader's previous knowledge to what is to be learned. The results were compared with predictions from Ausubel's model of assimilative learning. The results of the study indicated that advance organizers were associated…

The structure of common emotion regulation strategies: A meta-analytic examination.

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Naragon-Gainey, Kristin; McMahon, Tierney P; Chacko, Thomas P

2017-04-01

Emotion regulation has been examined extensively with regard to important outcomes, including psychological and physical health. However, the literature includes many different emotion regulation strategies but little examination of how they relate to one another, making it difficult to interpret and synthesize findings. The goal of this meta-analysis was to examine the underlying structure of common emotion regulation strategies (i.e., acceptance, behavioral avoidance, distraction, experiential avoidance, expressive suppression, mindfulness, problem solving, reappraisal, rumination, worry), and to evaluate this structure in light of theoretical models of emotion regulation. We also examined how distress tolerance-an important emotion regulation ability -relates to strategy use. We conducted meta-analyses estimating the correlations between emotion regulation strategies (based on 331 samples and 670 effect sizes), as well as between distress tolerance and strategies. The resulting meta-analytic correlation matrix was submitted to confirmatory and exploratory factor analyses. None of the confirmatory models, based on prior theory, was an acceptable fit to the data. Exploratory factor analysis suggested that 3 underlying factors best characterized these data. Two factors-labeled Disengagement and Aversive Cognitive Perseveration-emerged as strongly correlated but distinct factors, with the latter consisting of putatively maladaptive strategies. The third factor, Adaptive Engagement, was a less unified factor and weakly related to the other 2 factors. Distress tolerance was most closely associated with low levels of repetitive negative thought and experiential avoidance, and high levels of acceptance and mindfulness. We discuss the theoretical implications of these findings and applications to emotion regulation assessment. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The 'side effects' of medicalization: a meta-analytic review of how biogenetic explanations affect stigma.

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Kvaale, Erlend P; Haslam, Nick; Gottdiener, William H

2013-08-01

Reducing stigma is crucial for facilitating recovery from psychological problems. Viewing these problems biomedically may reduce the tendency to blame affected persons, but critics have cautioned that it could also increase other facets of stigma. We report on the first meta-analytic review of the effects of biogenetic explanations on stigma. A comprehensive search yielded 28 eligible experimental studies. Four separate meta-analyses (Ns=1207-3469) assessed the effects of biogenetic explanations on blame, perceived dangerousness, social distance, and prognostic pessimism. We found that biogenetic explanations reduce blame (Hedges g=-0.324) but induce pessimism (Hedges g=0.263). We also found that biogenetic explanations increase endorsement of the stereotype that people with psychological problems are dangerous (Hedges g=0.198), although this result could reflect publication bias. Finally, we found that biogenetic explanations do not typically affect social distance. Promoting biogenetic explanations to alleviate blame may induce pessimism and set the stage for self-fulfilling prophecies that could hamper recovery from psychological problems. Copyright © 2013 Elsevier Ltd. All rights reserved.

Workplace Waste Recycling Behaviour: A Meta-Analytical Review

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Adekunle Oke

2015-06-01

Full Text Available In order to increase waste recycling, many studies have been conducted to understand factors that may influence waste recycling behaviour. However, these studies have focused on household contexts rather than other waste generation contexts. As a result, this paper seeks to provide a detailed analysis of previous studies on workplace waste recycling behaviour. Drawing from different databases, 51 relevant studies on workplace waste recycling attitudes and behaviour were meta-analysed. Findings showed that the highest percentage of the existing studies were conducted in the USA, focused on a single waste stream, were often conducted within academic contexts, adopted (or modified an existing theoretical framework and were based on questionnaires which elicited self-reported behaviour. Some of the factors identified include demographics, situational variables, past behaviour, incentives, prompts and/or information, attitudes and identity. The findings highlighted the scale of challenges confronting waste management practitioners in understanding the factors that may affect waste recycling behaviour due to the complexity and heterogeneity of human behaviours. However, the results from the reviewed studies in this research suggest that a combination of different factors may be required to influence workplace waste recycling behaviour. This may provide effective incentives to develop a framework that may assist waste management stakeholders when addressing workplace waste management.

Altered Brain Activity in Unipolar Depression Revisited: Meta-analyses of Neuroimaging Studies.

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Müller, Veronika I; Cieslik, Edna C; Serbanescu, Ilinca; Laird, Angela R; Fox, Peter T; Eickhoff, Simon B

2017-01-01

major depressive disorder. For meta-analyses with a minimum of 17 experiments available, separate analyses were performed for increases and decreases. In total, 57 studies with 99 individual neuroimaging experiments comprising in total 1058 patients were included; 34 of them tested cognitive and 65 emotional processing. Overall analyses across cognitive processing experiments (P > .29) and across emotional processing experiments (P > .47) revealed no significant results. Similarly, no convergence was found in analyses investigating positive (all P > .15), negative (all P > .76), or memory (all P > .48) processes. Analyses that restricted inclusion of confounds (eg, medication, comorbidity, age) did not change the results. Inconsistencies exist across individual experiments investigating aberrant brain activity in UD and replication problems across previous neuroimaging meta-analyses. For individual experiments, these inconsistencies may relate to use of uncorrected inference procedures, differences in experimental design and contrasts, or heterogeneous clinical populations; meta-analytically, differences may be attributable to varying inclusion and exclusion criteria or rather liberal statistical inference approaches.

Effectiveness of cognitive behavioral therapy in the treatment of fibromyalgia syndrome: a meta-analytic literature review Effectiveness of cognitive behavioral therapy in the treatment of fibromyalgia syndrome: a meta-analytic literature review

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A. Minelli

2012-07-01

Full Text Available Fibromyalgia (FM is a chronic disorder caused by a dysfunction of central nervous system sensitization. This syndrome is characterized by widespread pain and diffuse tenderness, but often also presents fatigue, sleep disturbances, and a whole range of symptoms such as morning stiffness, decreased physical function and dyscognition. FM is usually treated with pharmacological and non-pharmacological treatments. The non-pharmacological interventions include cognitive behavioral therapy (CBT, physiotherapy, acupuncture and patient education programs. In order to evaluate the efficacy of CBT and compare it with other non-pharmacological treatments, we performed a review of the meta-analytic literature. We evaluated the methodological quality of publications found by following the recommendations of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Data showed that CBT does not provide better results than other non-pharmacological treatments on outcomes of pain, fatigue, sleep disturbance and quality of life, at either a short or long-term evaluation. On the contrary, CBT seems to be more effective on symptoms of depression for a short period, whereas it considerably improves the pain self-management and reduces the number of visits to the doctor. The data currently available indicate that cost-effectiveness studies could help us to understand whether the reduction in the number of visits to the doctor could balance the cost of CBT to the health public system.Fibromyalgia (FM is a chronic disorder caused by a dysfunction of central nervous system sensitization. This syndrome is characterized by widespread pain and diffuse tenderness, but often also presents fatigue, sleep disturbances, and a whole range of symptoms such as morning stiffness, decreased physical function and dyscognition. FM is usually treated with pharmacological and non-pharmacological treatments. The nonpharmacological interventions include

Implementation of evidence-based home visiting programs aimed at reducing child maltreatment: A meta-analytic review.

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Casillas, Katherine L; Fauchier, Angèle; Derkash, Bridget T; Garrido, Edward F

2016-03-01

In recent years there has been an increase in the popularity of home visitation programs as a means of addressing risk factors for child maltreatment. The evidence supporting the effectiveness of these programs from several meta-analyses, however, is mixed. One potential explanation for this inconsistency explored in the current study involves the manner in which these programs were implemented. In the current study we reviewed 156 studies associated with 9 different home visitation program models targeted to caregivers of children between the ages of 0 and 5. Meta-analytic techniques were used to determine the impact of 18 implementation factors (e.g., staff selection, training, supervision, fidelity monitoring, etc.) and four study characteristics (publication type, target population, study design, comparison group) in predicting program outcomes. Results from analyses revealed that several implementation factors, including training, supervision, and fidelity monitoring, had a significant effect on program outcomes, particularly child maltreatment outcomes. Study characteristics, including the program's target population and the comparison group employed, also had a significant effect on program outcomes. Implications of the study's results for those interested in implementing home visitation programs are discussed. A careful consideration and monitoring of program implementation is advised as a means of achieving optimal study results. Copyright © 2015 Elsevier Ltd. All rights reserved.

Plantar pressure in diabetic peripheral neuropathy patients with active foot ulceration, previous ulceration and no history of ulceration: a meta-analysis of observational studies.

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Fernando, Malindu Eranga; Crowther, Robert George; Pappas, Elise; Lazzarini, Peter Anthony; Cunningham, Margaret; Sangla, Kunwarjit Singh; Buttner, Petra; Golledge, Jonathan

2014-01-01

Elevated dynamic plantar pressures are a consistent finding in diabetes patients with peripheral neuropathy with implications for plantar foot ulceration. This meta-analysis aimed to compare the plantar pressures of diabetes patients that had peripheral neuropathy and those with neuropathy with active or previous foot ulcers. Published articles were identified from Medline via OVID, CINAHL, SCOPUS, INFORMIT, Cochrane Central EMBASE via OVID and Web of Science via ISI Web of Knowledge bibliographic databases. Observational studies reporting barefoot dynamic plantar pressure in adults with diabetic peripheral neuropathy, where at least one group had a history of plantar foot ulcers were included. Interventional studies, shod plantar pressure studies and studies not published in English were excluded. Overall mean peak plantar pressure (MPP) and pressure time integral (PTI) were primary outcomes. The six secondary outcomes were MPP and PTI at the rear foot, mid foot and fore foot. The protocol of the meta-analysis was published with PROPSERO, (registration number CRD42013004310). Eight observational studies were included. Overall MPP and PTI were greater in diabetic peripheral neuropathy patients with foot ulceration compared to those without ulceration (standardised mean difference 0.551, 95% CI 0.290-0.811, pdiabetic peripheral neuropathy with a history of foot ulceration compared to those with diabetic neuropathy without a history of ulceration. More homogenous data is needed to confirm these findings.

A meta-analytic review of psychological treatments for tinnitus.

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Andersson, G; Lyttkens, L

1999-08-01

Meta-analysis is a technique of combining results from different trials in order to obtain estimates of effects across studies. Meta-analysis has, as yet, rarely been used in audiological research. The aim of this paper was to conduct a meta-analysis on psychological treatment of tinnitus. The outcomes of 18 studies, including a total of 24 samples and up to 700 subjects, were included and coded. Included were studies on cognitive/cognitive-behavioural treatment, relaxation, hypnosis, biofeedback, educational sessions and problem-solving. Effect sizes for perceived tinnitus loudness, annoyance, negative affect (e.g. depression) and sleep problems were calculated for randomized controlled studies, pre-post-treatment design studies and follow-up results. Results showed strong to moderate effects on tinnitus annoyance for controlled studies (d = 0.86), pre-post designs (d = 0.5) and at follow-up (d = 0.48). Results on tinnitus loudness were weaker and disappeared at follow-up. Lower effect sizes were also obtained for measures of negative affect and sleep problems. Exploratory analyses revealed that cognitive-behavioural treatments were more effective on ratings of annoyance in the controlled studies. It is concluded that psychological treatment for tinnitus is effective, but that aspects such as depression and sleep problems may need to be targeted in future studies.

Meta-analytical study of productive and nutritional interactions of mycotoxins in broilers.

Science.gov (United States)

Andretta, I; Kipper, M; Lehnen, C R; Hauschild, L; Vale, M M; Lovatto, P A

2011-09-01

A meta-analysis was carried out to study the association of mycotoxins with performance, productive indices, and organ weights in broilers. Ninety-eight papers published between 1980 and 2009 were used, totaling 1,401 diets and 37,371 animals. Meta-analysis followed 3 sequential analyses: graphical, correlation, and variance-covariance. The mycotoxin presence in diets reduced (P mycotoxins with the greatest effect on feed intake and bird growth, reducing (P mycotoxin concentration in diets and the animal age at challenge were the variables that more improved the coefficient of determination for equations to estimate mycotoxin effect on weight gain. The mycotoxin effect on growth proved to be greater in young poultry. The residual analysis revealed that 65% of the variation in weight gain was explained by feed intake. The variation in weight gain of challenged broilers in relation to nonchallenged broilers was also influenced by ingestion of nutrients such as protein and methionine. Mortality was 8.8 and 2.8 times greater (P Mycotoxins also increased (P Mycotoxins influenced broiler performance, productive indices, and organ weights. However, the magnitude of the effects varied with type and concentration of mycotoxin, animal age, and nutritional factors.

Comparison of aerobic exercise, diet or both on lipids and lipoproteins in adults: a meta-analysis of randomized controlled trials

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Given that previous studies have reached conflicting conclusions regarding the effects of diet (D), aerobic exercise (E) or both (DE) on blood lipid and lipoprotein concentrations in adults, the meta-analytic approach was used to address this issue. Data Sources: Nine electronic databases, cross-ref...

A Meta-Analytic Review of Moral Licensing

NARCIS (Netherlands)

Blanken, Irene; van de Ven, Niels; Zeelenberg, Marcel

2015-01-01

Moral licensing refers to the effect that when people initially behave in a moral way, they are later more likely to display behaviors that are immoral, unethical, or otherwise problematic. We provide a state-of-the-art overview of moral licensing by conducting a meta-analysis of 91 studies (7,397

A meta-analytic review of moral licensing

NARCIS (Netherlands)

Blanken, I.; van de Ven, N.; Zeelenberg, M.

2015-01-01

Moral licensing refers to the effect that when people initially behave in a moral way, they are later more likely to display behaviors that are immoral, unethical, or otherwise problematic. We provide a state-of-the-art overview of moral licensing by conducting a meta-analysis of 91 studies (7,397

The Impact of Trial Stage, Developer Involvement and International Transferability on Universal Social and Emotional Learning Programme Outcomes: A Meta-Analysis

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Wigelsworth, M.; Lendrum, A.; Oldfield, J.; Scott, A.; ten Bokkel, I.; Tate, K.; Emery, C.

2016-01-01

This study expands upon the extant prior meta-analytic literature by exploring previously theorised reasons for the failure of school-based, universal social and emotional learning (SEL) programmes to produce expected results. Eighty-nine studies reporting the effects of school-based, universal SEL programmes were examined for differential effects…

Workplace mistreatment climate and potential employee and organizational outcomes: a meta-analytic review from the target's perspective.

Science.gov (United States)

Yang, Liu-Qin; Caughlin, David E; Gazica, Michele W; Truxillo, Donald M; Spector, Paul E

2014-07-01

This meta-analytic study summarizes relations between workplace mistreatment climate-MC (specific to incivility, aggression, and bullying) and potential outcomes. We define MC as individual or shared perceptions of organizational policies, procedures, and practices that deter interpersonal mistreatment. We located 35 studies reporting results with individual perceptions of MC (psychological MC) that yielded 36 independent samples comprising 91,950 employees. Through our meta-analyses, we found significant mean correlations between psychological MC and employee and organizational outcomes including mistreatment reduction effort (motivation and performance), mistreatment exposure, strains, and job attitudes. Moderator analyses revealed that the psychological MC-outcome relations were generally stronger for perceived civility climate than for perceived aggression-inhibition climate, and content contamination of existing climate scales accentuated the magnitude of the relations between psychological MC and some outcomes (mistreatment exposure and employee strains). Further, the magnitudes of the psychological MC-outcome relations were generally comparable across studies using dominant (i.e., most commonly used) and other climate scales, but for some focal relations, magnitudes varied with respect to cross-sectional versus prospective designs. The 4 studies that assessed MC at the unit-level had results largely consistent with those at the employee level.

The effect of dietary restriction on reproduction: a meta-analytic perspective.

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Moatt, Joshua P; Nakagawa, Shinichi; Lagisz, Malgorzata; Walling, Craig A

2016-10-07

Dietary restriction (DR), a reduction in the amount of food or particular nutrients eaten, is the most consistent environmental manipulation to extend lifespan and protect against age related diseases. Current evolutionary theory explains this effect as a shift in the resolution of the trade-off between lifespan and reproduction. However, recent studies have questioned the role of reproduction in mediating the effect of DR on longevity and no study has quantitatively investigated the effect of DR on reproduction across species. Here we report a comprehensive comparative meta-analysis of the effect of DR on reproduction. In general, DR reduced reproduction across taxa, but several factors moderated this effect. The effect of DR on reproduction was greater in well-studied model species (yeast, nematode worms, fruit flies and rodents) than non-model species. This mirrors recent results for longevity and, for reproduction, seems to result from a faster rate of decline with decreasing resources in model species. Our results also suggested that not all reproductive traits are affected equally by DR. High and moderate cost reproductive traits suffered a significant reduction with DR, but low cost traits, such as ejaculate production, did not. Although the effect of DR on reproduction was stronger in females than males, this sex difference reduced to near zero when accounting for other co-factors such as the costliness of the reproductive trait. Thus, sex differences in the effect of DR on longevity may be due to a failure to expose males to as complete a range of the costs of reproduction as females. We suggest that to better understand the generality of the effect of DR, future studies should attempt to address the cause of the apparent model species bias and ensure that individuals are exposed to as many of the costs of reproduction as possible. Furthermore, our meta-analytic approach reveals a general shortage of DR studies that record reproduction, particularly in

Intergenerational Transmission of Work Values: A Meta-Analytic Review.

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Cemalcilar, Zeynep; Secinti, Ekin; Sumer, Nebi

2018-05-09

Work values act as guiding principles for individuals' work-related behavior. Economic self-sufficiency is an important predictor for psychological well-being in adulthood. Longitudinal research has demonstrated work values to be an important predictor of economic behavior, and consequently of self-sufficiency. Socialization theories designate parents an important role in the socialization of their children to cultural values. Yet, extant literature is limited in demonstrating the role families play on how youth develop agentic pathways and seek self-sufficiency in transition to adulthood. This study presents a meta-analytic review investigating the intergenerational transmission of work values, which is frequently assessed in terms of parent-child value similarities. Thirty studies from 11 countries (N = 19,987; Median child age = 18.15) were included in the analyses. The results revealed a significant effect of parents on their children's work values. Both mothers' and fathers' work values, and their parenting behavior were significantly associated with their children's work values. Yet, similarity of father-child work values decreased as child age increased. Our findings suggest a moderate effect, suggesting the influence of general socio-cultural context, such as generational differences and peer influences, in addition to those of parents on youth's value acquisition. Our systematic review also revealed that, despite its theoretical and practical importance, social science literature is scarce in comprehensive and comparative empirical studies that investigate parent-child work value similarity. We discuss the implications of our findings for labor market and policy makers.

Prospective Linkages between Peer Victimization and Externalizing Problems in Children: A Meta-Analysis

NARCIS (Netherlands)

Reijntjes, A.; Kamphuis, J.H.; Prinzie, P.; Boelen, P.A.; van der Schoot, M.; Telch, M.J.

2011-01-01

Previous meta-analytic research has shown both concurrent and prospective linkages between peer victimization and internalizing problems in youth. However, the linkages between peer victimization and externalizing problems over time have not been systematically examined, and it is therefore unknown

Likelihood-Based Clustering of Meta-Analytic SROC Curves

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Holling, Heinz; Bohning, Walailuck; Bohning, Dankmar

2012-01-01

Meta-analysis of diagnostic studies experience the common problem that different studies might not be comparable since they have been using a different cut-off value for the continuous or ordered categorical diagnostic test value defining different regions for which the diagnostic test is defined to be positive. Hence specificities and…

A meta-analytically derived nomological network of procrastination

NARCIS (Netherlands)

Eerde, van W.

2003-01-01

This meta-analysis contains the correlations of 121 studies examining the relation between procrastination and personality variables, motives, affect, and performance. The largest negative effect sizes were found in relation to conscientiousness and self-efficacy, and the largest positive relation

Drug abuse and aggression between intimate partners: a meta-analytic review.

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Moore, Todd M; Stuart, Gregory L; Meehan, Jeffrey C; Rhatigan, Deborah L; Hellmuth, Julianne C; Keen, Stefanie M

2008-02-01

The present investigation employed meta-analytic procedures to quantitatively evaluate the empirical evidence on the relationship between drug abuse and aggression between intimate partners. Data from 96 studies yielding 547 effect sizes indicated that increases in drug use and drug-related problems were significantly associated with increases in aggression between intimate partners (d= .27). Cocaine emerged as the illicit substance with the strongest relationship to psychological, physical, and sexual aggression (ds= .39 to .62). Marijuana was also identified as having a significant association with partner aggression. Results showed comparable effect sizes for men and women, regardless of the sex of the drug user and/or perpetrator of partner aggression, with female reports of aggression having yielded larger effect sizes than male reports. Moderator analyses revealed that relative to other groups, married or cohabiting couples and Black participants evidenced significantly stronger effect sizes. The findings are discussed in relation to possible mechanisms linking drugs to partner aggression, and implications for future research are discussed in terms of focusing on conducting studies that assess the interaction of context and temporal sequencing of drugs and partner aggression.

A Meta-Analytic Review of Social Identification and Health in Organizational Contexts.

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Steffens, Niklas K; Haslam, S Alexander; Schuh, Sebastian C; Jetten, Jolanda; van Dick, Rolf

2017-11-01

We provide a meta-analytical review examining two decades of work on the relationship between individuals' social identifications and health in organizations (102 effect sizes, k = 58, N = 19,799). Results reveal a mean-weighted positive association between organizational identification and health ( r = .21, T = .14). Analysis identified a positive relationship for both workgroup ( r = .21) and organizational identification ( r = .21), and in studies using longitudinal/experimental ( r = .13) and cross-sectional designs ( r = .22). The relationship is stronger (a) for indicators of the presence of well-being ( r = .27) than absence of stress ( r = .18), (b) for psychological ( r = .23) than physical health ( r = .16), (c) to the extent that identification is shared among group members, and (d) as the proportion of female participants in a sample decreases. Overall, results indicate that social identifications in organizations are positively associated with health but that there is also substantial variation in effect size strength. We discuss implications for theory and practice and outline a roadmap for future research.

Offshore drilling effects in Brazilian SE marine sediments: a meta-analytical approach.

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Dore, Marina Pereira; Farias, Cássia; Hamacher, Cláudia

2017-01-01

The exploration and production of oil and gas reserves often result to drill cutting accumulations on the seafloor adjacent to drill locations. In this study, the detection of drilling influence on marine sediments was performed by meta-analytical comparison between data from pre- and post-drilling surveys undertaken in offshore Campos Basin, southeast of Brazil. Besides this overall appraisal on the geochemical variables, a multivariate assessment, considering only the post-drilling data, was performed. Among the variables, fines content, carbonates, total organic carbon, barium, chromium, copper, iron, manganese, nickel, lead, vanadium, zinc, and total petroleum hydrocarbons, only barium, copper, and hydrocarbons were related to drilling impacts. In relation to the point of discharge, relative elevated levels in the post-drilling campaigns were observed preferentially up to 500 m in the northeast and southwest directions, associated to the Brazil Current-predominant direction. Other distributed concentrations in the surroundings seem to indicate the dilution and dispersion of drilling waste promoted by meteoceanographic factors.

How much will be economic impact of climate change on water resources? A Meta-Analytic Review of previous literature

Science.gov (United States)

Yoshikawa, S.; Iseri, Y.; Kanae, S.

2016-12-01

Water resources is vital in social and economic activities. Total global water use is increasing, mainly due to economic and population growth in developing countries. It has one of risk with high agreement and robust evidence that freshwater-related risks of climate change increase significantly with increasing greenhouse gas concentrations. It is difficult to compare the risk with other field risk (e.g. agriculture, forestry, sea level rise) for considering both adaptation and mitigation policy with the level of decision makers and public servants. Economic impacts of climate change on water scarcity has been estimated by economic researchers. We have no certainty at all about integration between hydrological and economical fields on global scale. In this study, we highlight key concerns about conventional estimations of economic impact on water resources through meta-analysis. The economic impact on water resource in same base year using consumer price index is shown with increase in the global mean temperature. We clarified four concerns which are involved in 1) classification of economic mechanism, 2) estimated items of economic impact, 3) difference in estimating equations, and 4) definition of parameters related with economic impact of climate change. This study would be essential to next challenge as transdisciplinary research between hydrologic and economic fields.

A meta-analytic investigation of conscientiousness in the prediction of job performance: examining the intercorrelations and the incremental validity of narrow traits.

Science.gov (United States)

Dudley, Nicole M; Orvis, Karin A; Lebiecki, Justin E; Cortina, José M

2006-01-01

Researchers of broad and narrow traits have debated whether narrow traits are important to consider in the prediction of job performance. Because personality-performance relationship meta-analyses have focused almost exclusively on the Big Five, the predictive power of narrow traits has not been adequately examined. In this study, the authors address this question by meta-analytically examining the degree to which the narrow traits of conscientiousness predict above and beyond global conscientiousness. Results suggest that narrow traits do incrementally predict performance above and beyond global conscientiousness, yet the degree to which they contribute depends on the particular performance criterion and occupation in question. Overall, the results of this study suggest that there are benefits to considering the narrow traits of conscientiousness in the prediction of performance. (c) 2006 APA, all rights reserved.

Motivation Interventions in Education: A Meta-Analytic Review

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Lazowski, Rory A.; Hulleman, Chris S.

2016-01-01

This meta-analysis provides an extensive and organized summary of intervention studies in education that are grounded in motivation theory. We identified 74 published and unpublished papers that experimentally manipulated an independent variable and measured an authentic educational outcome within an ecologically valid educational context. Our…

Justice at the millennium: a meta-analytic review of 25 years of organizational justice research.

Science.gov (United States)

Colquitt, J A; Conlon, D E; Wesson, M J; Porter, C O; Ng, K Y

2001-06-01

The field of organizational justice continues to be marked by several important research questions, including the size of relationships among justice dimensions, the relative importance of different justice criteria, and the unique effects of justice dimensions on key outcomes. To address such questions, the authors conducted a meta-analytic review of 183 justice studies. The results suggest that although different justice dimensions are moderately to highly related, they contribute incremental variance explained in fairness perceptions. The results also illustrate the overall and unique relationships among distributive, procedural, interpersonal, and informational justice and several organizational outcomes (e.g., job satisfaction, organizational commitment, evaluation of authority, organizational citizenship behavior, withdrawal, performance). These findings are reviewed in terms of their implications for future research on organizational justice.

A meta-analytic review of the relationship between family accommodation and OCD symptom severity.

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Strauss, Clara; Hale, Lucy; Stobie, Blake

2015-06-01

Accommodation of obsessive compulsive disorder (OCD) symptoms by family members is common. This paper presents a systematic meta-analytic review on family accommodation and OCD symptom severity. Fourteen studies investigating the relationship between family accommodation and OCD symptoms were selected. The medium effect size of the relationship between family accommodation and OCD symptom severity was significant (r = .35; 95% CI: .23 to .47), based on a Hunter-Schmidt random effects model with a total of 849 participants. Although there was some evidence of publication bias, Rosenthal's fail-safe N suggested that 596 studies with zero effect would be needed to reduce the mean effect size to non-significant. Findings are discussed in the context of the limitations of the studies, and in particular the reliance on cross-sectional designs which impede causal conclusions. Future research to evaluate a family accommodation intervention in a randomized controlled design and using mediation analysis to explore change mechanisms is called for. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spatial effects in meta-foodwebs.

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Barter, Edmund; Gross, Thilo

2017-08-30

In ecology it is widely recognised that many landscapes comprise a network of discrete patches of habitat. The species that inhabit the patches interact with each other through a foodweb, the network of feeding interactions. The meta-foodweb model proposed by Pillai et al. combines the feeding relationships at each patch with the dispersal of species between patches, such that the whole system is represented by a network of networks. Previous work on meta-foodwebs has focussed on landscape networks that do not have an explicit spatial embedding, but in real landscapes the patches are usually distributed in space. Here we compare the dispersal of a meta-foodweb on Erdős-Rényi networks, that do not have a spatial embedding, and random geometric networks, that do have a spatial embedding. We found that local structure and large network distances in spatially embedded networks, lead to meso-scale patterns of patch occupation by both specialist and omnivorous species. In particular, we found that spatial separations make the coexistence of competing species more likely. Our results highlight the effects of spatial embeddings for meta-foodweb models, and the need for new analytical approaches to them.

Social relationships and cognitive decline : a systematic review and meta-analysis of longitudinal cohort studies

NARCIS (Netherlands)

Kuiper, Jisca S.; Zuidersma, Marij; Zuidema, Sytse U.; Burgerhof, Johannes G. M.; Stolk, Ronald P.; Oude Voshaar, Richard C.; Smidt, Nynke

Background: Although poor social relationships are assumed to contribute to cognitive decline, meta-analytic approaches have not been applied. Individual study results are mixed and difficult to interpret due to heterogeneity in measures of social relationships. We conducted a systematic review and

Social relationships and cognitive decline: a systematic review and meta-analysis of longitudinal cohort studies

NARCIS (Netherlands)

Kuiper, J.S.; Zuidersma, M.; Zuidema, S.U.; Burgerhof, J.G.; Stolk, R.P.; Oude Voshaar, R.C.; Smidt, N.

2016-01-01

BACKGROUND: Although poor social relationships are assumed to contribute to cognitive decline, meta-analytic approaches have not been applied. Individual study results are mixed and difficult to interpret due to heterogeneity in measures of social relationships. We conducted a systematic review and

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.

Choice-impulsivity in children and adolescents with attention-deficit/hyperactivity disorder (ADHD): A meta-analytic review.

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Patros, Connor H G; Alderson, R Matt; Kasper, Lisa J; Tarle, Stephanie J; Lea, Sarah E; Hudec, Kristen L

2016-02-01

Impulsive behavior is a core DSM-5 diagnostic feature of attention-deficit/hyperactivity disorder (ADHD) that is associated with several pejorative outcomes. Impulsivity is multidimensional, consisting of two sub-constructs: rapid-response impulsivity and reward-delay impulsivity (i.e., choice-impulsivity). While previous research has extensively examined the presence and implications of rapid-response impulsivity in children with ADHD, reviews of choice-impulsive behavior have been both sparse and relatively circumscribed. This review used meta-analytic methods to comprehensively examine between-group differences in choice-impulsivity among children and adolescents with and without ADHD. Twenty-eight tasks (from 26 studies), consisting of 4320 total children (ADHD=2360, TD=1,960), provided sufficient information to compute an overall between-group effect size for choice-impulsivity performance. Results revealed a medium-magnitude between-group effect size (g=.47), suggesting that children and adolescents with ADHD exhibited moderately increased impulsive decision-making compared to TD children and adolescents. Further, relative to the TD group, children and adolescents with ADHD exhibited similar patterns of impulsive decision-making across delay discounting and delay of gratification tasks. However, the use of single-informant diagnostic procedures relative to multiple informants yielded larger between-group effects, and a similar pattern was observed across samples that excluded females relative to samples that included females. Copyright © 2015 Elsevier Ltd. All rights reserved.

Use of the Wechsler Adult Intelligence Scale Digit Span subtest for malingering detection: a meta-analytic review.

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Jasinski, Lindsey J; Berry, David T R; Shandera, Anni L; Clark, Jessica A

2011-03-01

Twenty-four studies utilizing the Wechsler Adult Intelligence Scale (WAIS) Digit Span subtest--either the Reliable Digit Span (RDS) or Age-Corrected Scaled Score (DS-ACSS) variant--for malingering detection were meta-analytically reviewed to evaluate their effectiveness in detecting malingered neurocognitive dysfunction. RDS and DS-ACSS effectively discriminated between honest responders and dissimulators, with average weighted effect sizes of 1.34 and 1.08, respectively. No significant differences were found between RDS and DS-ACSS. Similarly, no differences were found between the Digit Span subtest from the WAIS or Wechsler Memory Scale (WMS). Strong specificity and moderate sensitivity were observed, and optimal cutting scores are recommended.

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

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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/ .

A meta-analytic investigation of the relation between interpersonal attraction and enacted behavior.

Science.gov (United States)

Montoya, R Matthew; Kershaw, Christine; Prosser, Julie L

2018-05-07

We present a meta-analysis that investigated the relation between self-reported interpersonal attraction and enacted behavior. Our synthesis focused on (a) identifying the behaviors related to attraction; (b) evaluating the efficacy of models of the relation between attraction and behavior; (c) testing the impact of several moderators, including evaluative threat salience, cognitive appraisal salience, and the sex composition of the social interaction; and (d) investigating the degree of agreement between the meta-analytic findings and an ethnographic analysis. Using a multilevel modeling approach, an analysis of 309 effect sizes (N = 5,422) revealed a significant association (z = .20) between self-reported attraction and enacted behavior. Key findings include: (a) that the specific behaviors associated with attraction (e.g., eye contact, smiling, laughter, mimicry) are those behaviors research has linked to the development of trust/rapport; (b) direct behaviors (e.g., physical proximity, talking to), compared with indirect behaviors (e.g., eye contact, smiling, mimicry), were more strongly related to self-reported attraction; and (c) evaluative threat salience (e.g., fear of rejection) reduced the magnitude of the relation between direct behavior and affective attraction. Moreover, an ethnographic analysis revealed consistency between the behaviors identified by the meta-analysis and those behaviors identified by ethnographers as predictive of attraction. We discuss the implications of our findings for models of the relation between attraction and behavior, for the behavioral expressions of emotions, and for how attraction is measured and conceptualized. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Efficacy of working memory training in children and adolescents with learning disabilities: A review study and meta-analysis.

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Peijnenborgh, Janneke C A W; Hurks, Petra M; Aldenkamp, Albert P; Vles, Johan S H; Hendriksen, Jos G M

2016-10-01

The effectiveness of working memory (WM) training programmes is still a subject of debate. Previous reviews were heterogeneous with regard to participant characteristics of the studies included. To examine whether these programmes are of added value for children with learning disabilities (LDs), a systematic meta-analytic review was undertaken focusing specifically on LDs. Thirteen randomised controlled studies were included, with a total of 307 participants (age range = 5.5-17, Mean age across studies = 10.61, SD = 1.77). Potential moderator variables were examined, i.e., age, type of LD, training programme, training dose, design type, and type of control group. The meta-analysis indicated reliable short-term improvements in verbal WM, visuo-spatial WM, and word decoding in children with LDs after training (effect sizes ranged between 0.36 and 0.63), when compared to the untrained control group. These improvements sustained over time for up to eight months. Furthermore, children > 10 years seemed to benefit more in terms of verbal WM than younger children, both immediately after training as well as in the long-term. Other moderator variables did not have an effect on treatment efficacy.

The influence of discrete emotions on judgement and decision-making: a meta-analytic review.

Science.gov (United States)

Angie, Amanda D; Connelly, Shane; Waples, Ethan P; Kligyte, Vykinta

2011-12-01

During the past three decades, researchers interested in emotions and cognition have attempted to understand the relationship that affect and emotions have with cognitive outcomes such as judgement and decision-making. Recent research has revealed the importance of examining more discrete emotions, showing that same-valence emotions (e.g., anger and fear) differentially impact judgement and decision-making outcomes. Narrative reviews of the literature (Lerner & Tiedens, 2006 ; Pham, 2007 ) have identified some under-researched topics, but provide a limited synthesis of findings. The purpose of this study was to review the research examining the influence of discrete emotions on judgement and decision-making outcomes and provide an assessment of the observed effects using a meta-analytic approach. Results, overall, show that discrete emotions have moderate to large effects on judgement and decision-making outcomes. However, moderator analyses revealed differential effects for study-design characteristics and emotion-manipulation characteristics by emotion type. Implications are discussed.

The TEACCH program for children and adults with autism: a meta-analysis of intervention studies.

Science.gov (United States)

Virues-Ortega, Javier; Julio, Flávia M; Pastor-Barriuso, Roberto

2013-12-01

The intervention program for autism known as Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH) is considered an emerging practice for autism. In the present study we used state-of-the-art meta-analytical procedures to examine the pooled clinical effects of TEACCH in a variety of outcomes. A total of 13 studies were selected for meta-analysis totaling 172 individuals with autism exposed to TEACCH. Standardized measures of perceptual, motor, adaptive, verbal and cognitive skills were identified as treatment outcomes. We used inverse-variance weighted random effects meta-analysis supplemented with quality assessment, sensitivity analysis, meta-regression, and heterogeneity and publication bias tests. The results suggested that TEACCH effects on perceptual, motor, verbal and cognitive skills were of small magnitude in the meta-analyzed studies. Effects over adaptive behavioral repertoires including communication, activities of daily living, and motor functioning were within the negligible to small range. There were moderate to large gains in social behavior and maladaptive behavior. The effects of the TEACCH program were not moderated by aspects of the intervention such as duration (total weeks), intensity (hours per week), and setting (home-based vs. center-based). While the present meta-analysis provided limited support for the TEACCH program as a comprehensive intervention, our results should be considered exploratory owing to the limited pool of studies available. © 2013.

Variables As Currency: Linking Meta-Analysis Research and Data Paths in Sciences

Directory of Open Access Journals (Sweden)

Hua Qin

2014-11-01

Full Text Available Meta-analyses are studies that bring together data or results from multiple independent studies to produce new and over-arching findings. Current data curation systems only partially support meta-analytic research. Some important meta-analytic tasks, such as the selection of relevant studies for review and the integration of research datasets or findings, are not well supported in current data curation systems. To design tools and services that more fully support meta-analyses, we need a better understanding of meta-analytic research. This includes an understanding of both the practices of researchers who perform the analyses and the characteristics of the individual studies that are brought together. In this study, we make an initial contribution to filling this gap by developing a conceptual framework linking meta-analyses with data paths represented in published articles selected for the analysis. The framework focuses on key variables that represent primary/secondary datasets or derived socio-ecological data, contexts of use, and the data transformations that are applied. We introduce the notion of using variables and their relevant information (e.g., metadata and variable relationships as a type of currency to facilitate synthesis of findings across individual studies and leverage larger bodies of relevant source data produced in small science research. Handling variables in this manner provides an equalizing factor between data from otherwise disparate data-producing communities. We conclude with implications for exploring data integration and synthesis issues as well as system development.

Angry Birds, Angry Children, and Angry Meta-Analysts: A Reanalysis.

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Furuya-Kanamori, Luis; Doi, Suhail A R

2016-05-01

Ferguson's (2015a) meta-analysis assessed a very important and controversial topic about children's mental health and video games. In response to the concerns raised by researchers about the appropriateness of the meta-analytical methods used by Ferguson; we decided to reanalyze the data and discuss two major misconceptions about meta-analysis. We argue that partial correlations can (and should) be meta-analyzed instead of zero-order bivariate correlations if the predictors included in the partial correlation represent a similar construct. We also discuss the fallacy by which the conventional meta-analytical model assumes that the studies' effect sizes came into being according to the same random effect construct used by the analysis. Our replication results using partial correlations, standardized (valid and reliable) outcomes, and an improved meta-analytical model (that does not assume a random effect is the mechanism of data generation) confirmed the main results of Ferguson's meta-analysis. There was a significant yet very small effect on aggressive behavior of exposure to both general, rp = 0.062, 95% CI [0.012, 0.112], and violent, rp = 0.055, 95% CI [0.019, 0.091], video games. A very small effect was seen on reduced prosocial behavior, but this was only in the general video game exposure category, rp = 0.072, 95% CI [0.045, 0.100]. © The Author(s) 2016.

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

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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

Pancultural self-enhancement reloaded: a meta-analytic reply to Heine (2005).

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Sedikides, Constantine; Gaertner, Lowell; Vevea, Jack L

2005-10-01

C. Sedikides, L. Gaertner, and Y. Toguchi (2003) reported findings favoring the universality of self-enhancement. S. J. Heine (2005) challenged the authors' research on evidential and logical grounds. In response, the authors carried out 2 meta-analytic investigations. The results backed the C. Sedikides et al. (2003) theory and findings. Both Westerners and Easterners self-enhanced tactically. Westerners self-enhanced on attributes relevant to the cultural ideal of individualism, whereas Easterners self-enhanced on attributes relevant to the cultural ideal of collectivism (in both cases, because of the personal importance of the ideal). Self-enhancement motivation is universal, although its manifestations are strategically sensitive to cultural context. The authors respond to other aspects of Heine's critique by discussing why researchers should empirically validate the comparison dimension (individualistic vs. collectivistic) and defending why the better-than-average effect is a valid measure of self-enhancement.

Is computerised CBT really helpful for adult depression?-A meta-analytic re-evaluation of CCBT for adult depression in terms of clinical implementation and methodological validity.

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So, Mirai; Yamaguchi, Sosei; Hashimoto, Sora; Sado, Mitsuhiro; Furukawa, Toshi A; McCrone, Paul

2013-04-15

Depression is a major cause of disability worldwide, and computerised cognitive behavioural therapy (CCBT) is expected to be a more augmentative and efficient treatment. According to previous meta-analyses of CCBT, there is a need for a meta-analytic revaluation of the short-term effectiveness of this therapy and for an evaluation of its long-term effects, functional improvement and dropout. Five databases were used (MEDLINE, PsycINFO, EMBASE, CENTRAL and CiNii). We included all RCTs with proper concealment and blinding of outcome assessment for the clinical effectiveness of CCBT in adults (aged 18 and over) with depression. Using Cohen's method, the standard mean difference (SMD) for the overall pooled effects across the included studies was estimated with a random effect model. The main outcome measure and the relative risk of dropout were included in the meta-analysis. Fourteen trials met the inclusion criteria, and sixteen comparisons from these were used for the largest meta-analysis ever. All research used appropriate random sequence generation and Intention-to-Treat analyses (ITT), and employed self-reported measures as the primary outcome. For the sixteen comparisons (2807 participants) comparing CCBT and control conditions, the pooled SMD was -0.48 [95% IC -0.63 to -0.33], suggesting similar effect to the past reviews. Also, there was no significant clinical effect at long follow-up and no improvement of function found. Furthermore, a significantly higher drop-out rate was found for CCBT than for controls. When including studies without BDI as a rating scale and with only modern imputation as sensitivity analysis, the pooled SMD remained significant despite the reduction from a moderate to a small effect. Significant publication bias was found in a funnel plot and on two tests (Begg's p = 0.09; Egger's p = 0.01). Using a trim and fill analysis, the SMD was -0.32 [95% CI -0.49 to -0.16]. Despite a short-term reduction in depression at post-treatment, the

Psychosocial work environment and mental health--a meta-analytic review.

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Stansfeld, Stephen; Candy, Bridget

2006-12-01

To clarify the associations between psychosocial work stressors and mental ill health, a meta-analysis of psychosocial work stressors and common mental disorders was undertaken using longitudinal studies identified through a systematic literature review. The review used a standardized search strategy and strict inclusion and quality criteria in seven databases in 1994-2005. Papers were identified from 24,939 citations covering social determinants of health, 50 relevant papers were identified, 38 fulfilled inclusion criteria, and 11 were suitable for a meta-analysis. The Comprehensive Meta-analysis Programme was used for decision authority, decision latitude, psychological demands, and work social support, components of the job-strain and iso-strain models, and the combination of effort and reward that makes up the effort-reward imbalance model and job insecurity. Cochran's Q statistic assessed the heterogeneity of the results, and the I2 statistic determined any inconsistency between studies. Job strain, low decision latitude, low social support, high psychological demands, effort-reward imbalance, and high job insecurity predicted common mental disorders despite the heterogeneity for psychological demands and social support among men. The strongest effects were found for job strain and effort-reward imbalance. This meta-analysis provides robust consistent evidence that (combinations of) high demands and low decision latitude and (combinations of) high efforts and low rewards are prospective risk factors for common mental disorders and suggests that the psychosocial work environment is important for mental health. The associations are not merely explained by response bias. The impact of work stressors on common mental disorders differs for women and men.

The nature of verbal memory impairment in multiple sclerosis: a list-learning and meta-analytic study.

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Lafosse, Jose M; Mitchell, Sandra M; Corboy, John R; Filley, Christopher M

2013-10-01

The primary purpose of this study was to test the hypothesis that multiple sclerosis (MS) patients have impaired acquisition rather than a retrieval deficit. Verbal memory impairment in MS was examined in 53 relapsing-remitting MS patients and 31 healthy controls (HC), and in a meta-analysis of studies that examined memory functioning in MS with list-learning tasks. The MS group demonstrated significantly lower acquisition and delayed recall performance than the HC group, and the meta-analysis revealed that the largest effect sizes were obtained for acquisition measures relative to delayed recall and recognition. Our data argue against a retrieval deficit as the sole explanation for verbal memory impairment in MS, and make a consistent case for the position that deficient acquisition contributes to the memory dysfunction of MS patients. Deficient acquisition may result from demyelination in relevant white matter tracts that reduces encoding efficiency as a result of impaired speed of information processing.

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.

Depressive realism: a meta-analytic review.

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Moore, Michael T; Fresco, David M

2012-08-01

The current investigation represents the first meta-analysis of the depressive realism literature. A search of this literature revealed 75 relevant studies representing 7305 participants from across the US and Canada, as well as from England, Spain, and Israel. Results generally indicated a small overall depressive realism effect (Cohen's d=-.07). Overall, however, both dysphoric/depressed individuals (d=.14) and nondysphoric/nondepressed individuals evidenced a substantial positive bias (d=.29), with this bias being larger in nondysphoric/nondepressed individuals. Examination of potential moderator variables indicated that studies lacking an objective standard of reality (d=-.15 versus -.03, for studies possessing such a standard) and that utilize self-report measures to measure symptoms of depression (d=.16 versus -.04, for studies which utilize structured interviews) were more likely to find depressive realism effects. Methodological paradigm was also found to influence whether results consistent with depressive realism were found (d's ranged from -.09 to .14). Copyright © 2012 Elsevier Ltd. All rights reserved.

Why and when hierarchy impacts team effectiveness: A meta-analytic integration.

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Greer, Lindred L; de Jong, Bart A; Schouten, Maartje E; Dannals, Jennifer E

2018-06-01

Hierarchy has the potential to both benefit and harm team effectiveness. In this article, we meta-analytically investigate different explanations for why and when hierarchy helps or hurts team effectiveness, drawing on results from 54 prior studies (N = 13,914 teams). Our findings show that, on net, hierarchy negatively impacts team effectiveness (performance: ρ = -.08; viability: ρ = -.11), and that this effect is mediated by increased conflict-enabling states. Additionally, we show that the negative relationship between hierarchy and team performance is exacerbated by aspects of the team structure (i.e., membership instability, skill differentiation) and the hierarchy itself (i.e., mutability), which make hierarchical teams prone to conflict. The predictions regarding the positive effect of hierarchy on team performance as mediated by coordination-enabling processes, and the moderating roles of several aspects of team tasks (i.e., interdependence, complexity) and the hierarchy (i.e., form) were not supported, with the exception that task ambiguity enhanced the positive effects of hierarchy. Given that our findings largely support dysfunctional views on hierarchy, future research is needed to understand when and why hierarchy may be more likely to live up to its purported functional benefits. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Virtual reality measures in neuropsychological assessment: a meta-analytic review.

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Neguț, Alexandra; Matu, Silviu-Andrei; Sava, Florin Alin; David, Daniel

2016-02-01

Virtual reality-based assessment is a new paradigm for neuropsychological evaluation, that might provide an ecological assessment, compared to paper-and-pencil or computerized neuropsychological assessment. Previous research has focused on the use of virtual reality in neuropsychological assessment, but no meta-analysis focused on the sensitivity of virtual reality-based measures of cognitive processes in measuring cognitive processes in various populations. We found eighteen studies that compared the cognitive performance between clinical and healthy controls on virtual reality measures. Based on a random effects model, the results indicated a large effect size in favor of healthy controls (g = .95). For executive functions, memory and visuospatial analysis, subgroup analysis revealed moderate to large effect sizes, with superior performance in the case of healthy controls. Participants' mean age, type of clinical condition, type of exploration within virtual reality environments, and the presence of distractors were significant moderators. Our findings support the sensitivity of virtual reality-based measures in detecting cognitive impairment. They highlight the possibility of using virtual reality measures for neuropsychological assessment in research applications, as well as in clinical practice.

A systematic review of factors associated with accidental falls in people with multiple sclerosis: a meta-analytic approach.

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Giannì, Costanza; Prosperini, Luca; Jonsdottir, Johanna; Cattaneo, Davide

2014-07-01

To determine whether there are demographic, clinical, and instrumental variables useful to detect fall status of patients with multiple sclerosis. PubMed and the Cochrane Library. Eligible studies were identified by two independent investigators. Only studies having a clear distinction between fallers and non-fallers were included and meta-analysed. Odds ratios (ORs) and standard mean differences (SMDs) were calculated and pooled using fixed effect models. Among 115 screened articles, 15 fulfilled criteria for meta-analyses, with a total of 2425 patients included. Proportion of fallers may vary from 30% to 63% in a time frame from 1 to 12 months. No significant publication bias was found, even though 12/15 studies relied on retrospective reports of falls, thus introducing recall biases. Risk factors for falls varied across studies, owing to heterogeneity of populations included and clinical instruments used. The meta-analytic approach found that, compared with non-fallers, fallers had longer disease duration (SMD = 0.14, p = 0.02), progressive course of disease (OR = 2.02, p < 0.0001), assistive device for walking (OR = 3.16, p < 0.0001), greater overall disability level (SMD = 0.74, p < 0.0001), slower walking speed (SMD = 0.45, p = 0.0005), and worse performances in balance tests (Berg Balance Scale: SMD = -0.48, p = 0.002; Timed up-and-go test, SMD = 0.31, p = 0.04), and force-platform measures (postural sway) with eyes opened (SMD = 0.71, p = 0.006) and closed (SMD = 0.83, p = 0.01), respectively. Elucidations regarding risk factors for accidental falls in patients with multiple sclerosis (PwMs) are provided here, with worse disability score, progressive course, use of walking aid, and poorer performances in static and dynamic balance tests strongly associated with fall status. © The Author(s) 2014.

Visual Task Demands and the Auditory Mismatch Negativity: An Empirical Study and a Meta-Analysis.

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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.

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

Common brain areas engaged in false belief reasoning and visual perspective taking: A meta-analysis of functional brain imaging studies.

Directory of Open Access Journals (Sweden)

Matthias eSchurz

2013-11-01

Full Text Available We performed a quantitative meta-analysis of functional neuroimaging studies to identify brain areas which are commonly engaged in social and visuo-spatial perspective taking. Specifically, we compared brain activation found for visual-perspective taking to activation for false belief reasoning, a task which requires awareness of perspective to understand someone’s mistaken belief about the world which contrasts with reality. In support of a previous account by Perner & Leekam (2008, a meta-analytic conjunction analysis found activation for false belief reasoning and visual perspective taking in the left but not the right dorsal temporo-parietal junction. This fits with the idea that the left dorsal TPJ is responsible for representing different perspectives in a domain-general fashion. Moreover, the conjunction found activation in the precuneus and the left middle occipital gyrus close to the putative Extrastriate Body Area. The precuneus is linked to mental-imagery processes, which may aid in the construction of a different perspective. The Extrastriate Body Area may be engaged due to imagined body-transformations when another’s viewpoint is adopted.

Meta-analysis of workplace physical activity interventions.

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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.

Neurocognition and symptoms identify links between facial recognition and emotion processing in schizophrenia: meta-analytic findings.

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Ventura, Joseph; Wood, Rachel C; Jimenez, Amy M; Hellemann, Gerhard S

2013-12-01

In schizophrenia patients, one of the most commonly studied deficits of social cognition is emotion processing (EP), which has documented links to facial recognition (FR). But, how are deficits in facial recognition linked to emotion processing deficits? Can neurocognitive and symptom correlates of FR and EP help differentiate the unique contribution of FR to the domain of social cognition? A meta-analysis of 102 studies (combined n=4826) in schizophrenia patients was conducted to determine the magnitude and pattern of relationships between facial recognition, emotion processing, neurocognition, and type of symptom. Meta-analytic results indicated that facial recognition and emotion processing are strongly interrelated (r=.51). In addition, the relationship between FR and EP through voice prosody (r=.58) is as strong as the relationship between FR and EP based on facial stimuli (r=.53). Further, the relationship between emotion recognition, neurocognition, and symptoms is independent of the emotion processing modality - facial stimuli and voice prosody. The association between FR and EP that occurs through voice prosody suggests that FR is a fundamental cognitive process. The observed links between FR and EP might be due to bottom-up associations between neurocognition and EP, and not simply because most emotion recognition tasks use visual facial stimuli. In addition, links with symptoms, especially negative symptoms and disorganization, suggest possible symptom mechanisms that contribute to FR and EP deficits. © 2013 Elsevier B.V. All rights reserved.

On Conducting Construct Validity Meta-Analyses for the Rorschach: A Reply to Tibon Czopp and Zeligman (2016).

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Mihura, Joni L; Meyer, Gregory J; Dumitrascu, Nicolae; Bombel, George

2016-01-01

We respond to Tibon Czopp and Zeligman's (2016) critique of our systematic reviews and meta-analyses of 65 Rorschach Comprehensive System (CS) variables published in Psychological Bulletin (2013). The authors endorsed our supportive findings but critiqued the same methodology when used for the 13 unsupported variables. Unfortunately, their commentary was based on significant misunderstandings of our meta-analytic method and results, such as thinking we used introspectively assessed criteria in classifying levels of support and reporting only a subset of our externally assessed criteria. We systematically address their arguments that our construct label and criterion variable choices were inaccurate and, therefore, meta-analytic validity for these 13 CS variables was artificially low. For example, the authors created new construct labels for these variables that they called "the customary CS interpretation," but did not describe their methodology nor provide evidence that their labels would result in better validity than ours. They cite studies they believe we should have included; we explain how these studies did not fit our inclusion criteria and that including them would have actually reduced the relevant CS variables' meta-analytic validity. Ultimately, criticisms alone cannot change meta-analytic support from negative to positive; Tibon Czopp and Zeligman would need to conduct their own construct validity meta-analyses.

Do people with chronic pain have impaired executive function? A meta-analytical review.

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Berryman, Carolyn; Stanton, Tasha R; Bowering, K Jane; Tabor, Abby; McFarlane, Alexander; Moseley, G Lorimer

2014-11-01

A widely held belief within the clinical community is that chronic pain is associated with cognitive impairment, despite the absence of a definitive systematic review or meta-analysis on the topic. The current systematic review and meta-analysis aimed to establish the current evidence concerning the difference in executive function between people with chronic pain and healthy controls. Six databases were searched for citations related to executive function and chronic pain from inception to June 24, 2013. Two reviewers independently assessed studies for eligibility and extracted relevant data according to the Cochrane Collaboration and Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Twenty five studies were included in the review and twenty two studies in the meta-analysis. A small to moderate impairment in executive function performance was found in people with chronic pain across cognitive components, although all studies had a high risk of bias. The current evidence suggests impairment of executive function in people with chronic pain, however, important caveats exist. First, executive function involves many cognitive components and there is no standard test for it. Second, moderators of executive function, such as medication and sleep, were seldom controlled for in studies of executive function performance. Copyright © 2014 Elsevier Ltd. All rights reserved.

A meta-analytic review of gender differences in perceptions of sexual harassment.

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Rotundo, M; Nguyen, D H; Sackett, P R

2001-10-01

Research on gender differences in perceptions of sexual harassment informs an ongoing legal debate regarding the use of a reasonable person standard instead of a reasonable woman standard to evaluate sexual harassment claims. The authors report a meta-analysis of 62 studies of gender differences in harassment perceptions. An earlier quantitative review combined all types of social-sexual behaviors for a single meta-analysis; the purpose of this study was to investigate whether the magnitude of the female-male difference varies by type of behavior. An overall standardized mean difference of 0.30 was found, suggesting that women perceive a broader range of social-sexual behaviors as harassing. However, the meta-analysis also found that the female-male difference was larger for behaviors that involve hostile work environment harassment, derogatory attitudes toward women, dating pressure, or physical sexual contact than sexual propositions or sexual coercion.

Loneliness and social isolation as risk factors for mortality: a meta-analytic review.

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Holt-Lunstad, Julianne; Smith, Timothy B; Baker, Mark; Harris, Tyler; Stephenson, David

2015-03-01

Actual and perceived social isolation are both associated with increased risk for early mortality. In this meta-analytic review, our objective is to establish the overall and relative magnitude of social isolation and loneliness and to examine possible moderators. We conducted a literature search of studies (January 1980 to February 2014) using MEDLINE, CINAHL, PsycINFO, Social Work Abstracts, and Google Scholar. The included studies provided quantitative data on mortality as affected by loneliness, social isolation, or living alone. Across studies in which several possible confounds were statistically controlled for, the weighted average effect sizes were as follows: social isolation odds ratio (OR) = 1.29, loneliness OR = 1.26, and living alone OR = 1.32, corresponding to an average of 29%, 26%, and 32% increased likelihood of mortality, respectively. We found no differences between measures of objective and subjective social isolation. Results remain consistent across gender, length of follow-up, and world region, but initial health status has an influence on the findings. Results also differ across participant age, with social deficits being more predictive of death in samples with an average age younger than 65 years. Overall, the influence of both objective and subjective social isolation on risk for mortality is comparable with well-established risk factors for mortality. © The Author(s) 2015.

Anxiety Levels in Children with Autism Spectrum Disorder : A Meta-Analysis

NARCIS (Netherlands)

van Steensel, F.J.A.; Heeman, E.J.

The aim of the current study was to meta-analytically examine whether anxiety levels in children with autism spectrum disorders (ASD) are elevated. A total of 83 articles were selected from a systematic literature search and were included in the meta-analyses. Results demonstrated that children with

Interventions to reduce sexual prejudice: a study-space analysis and meta-analytic review.

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Bartoş, Sebastian E; Berger, Israel; Hegarty, Peter

2014-01-01

Sexual prejudice is an important threat to the physical and mental well-being of lesbians, gay men, and bisexual people. Therefore, we reviewed the effectiveness of interventions designed to reduce such prejudice. A study-space analysis was performed on published and unpublished papers from all over the world to identify well-studied and underexplored issues. Most studies were conducted with North American undergraduates and were educational in nature. Dissertations were often innovative and well designed but were rarely published. We then performed meta-analyses on sets of comparable studies. Education, contact with gay people, and combining contact with education had a medium-size effect on several measures of sexual prejudice. The manipulation of social norms was effective in reducing antigay behavior. Other promising interventions, such as the use of entertainment media to promote tolerance, need further investigation. More research is also needed on populations other than American students, particularly groups who may have higher levels of sexual prejudice.

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

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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.

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

Organizational culture and organizational effectiveness: a meta-analytic investigation of the competing values framework's theoretical suppositions.

Science.gov (United States)

Hartnell, Chad A; Ou, Amy Yi; Kinicki, Angelo

2011-07-01

We apply Quinn and Rohrbaugh's (1983) competing values framework (CVF) as an organizing taxonomy to meta-analytically test hypotheses about the relationship between 3 culture types and 3 major indices of organizational effectiveness (employee attitudes, operational performance [i.e., innovation and product and service quality], and financial performance). The paper also tests theoretical suppositions undergirding the CVF by investigating the framework's nomological validity and proposed internal structure (i.e., interrelationships among culture types). Results based on data from 84 empirical studies with 94 independent samples indicate that clan, adhocracy, and market cultures are differentially and positively associated with the effectiveness criteria, though not always as hypothesized. The findings provide mixed support for the CVF's nomological validity and fail to support aspects of the CVF's proposed internal structure. We propose an alternative theoretical approach to the CVF and delineate directions for future research.

Association between individual differences in non-symbolic number acuity and math performance: a meta-analysis.

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Chen, Qixuan; Li, Jingguang

2014-05-01

Many recent studies have examined the association between number acuity, which is the ability to rapidly and non-symbolically estimate the quantity of items appearing in a scene, and symbolic math performance. However, various contradictory results have been reported. To comprehensively evaluate the association between number acuity and symbolic math performance, we conduct a meta-analysis to synthesize the results observed in previous studies. First, a meta-analysis of cross-sectional studies (36 samples, N = 4705) revealed a significant positive correlation between these skills (r = 0.20, 95% CI = [0.14, 0.26]); the association remained after considering other potential moderators (e.g., whether general cognitive abilities were controlled). Moreover, a meta-analysis of longitudinal studies revealed 1) that number acuity may prospectively predict later math performance (r = 0.24, 95% CI = [0.11, 0.37]; 6 samples) and 2) that number acuity is retrospectively correlated to early math performance as well (r = 0.17, 95% CI = [0.07, 0.26]; 5 samples). In summary, these pieces of evidence demonstrate a moderate but statistically significant association between number acuity and math performance. Based on the estimated effect sizes, power analyses were conducted, which suggested that many previous studies were underpowered due to small sample sizes. This may account for the disparity between findings in the literature, at least in part. Finally, the theoretical and practical implications of our meta-analytic findings are presented, and future research questions are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

Transaction cost determinants and ownership-based entry mode choice: a meta-analytical review

OpenAIRE

Hongxin Zhao; Yadong Luo; Taewon Suh

2004-01-01

Entry mode choice is a critical ingredient of international entry strategies, and has been voluminously examined in the field. The findings, however, are very mixed, especially with respect to transaction-cost-related factors in determining the ownership-based entry mode choice. This study conducted a meta-analysis to quantitatively summarize the literature and empirically generalize more conclusive findings. Based on the 106 effect sizes of 38 empirical studies, the meta-analysis shows that ...

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

Comparison of milk fatty acid profiles measured on Kouri cows near Lake Chad and on dairy cattle as reported by meta-analytical data.

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Bada Algom, O; Fabry, C; Leroy, P L; Hornick, J-L

2017-06-01

Kouri (Bos taurus) is a breed aboriginal from Lake Chad and threatened with extinction. This study aimed to compare milk fatty acid profiles measured on Kouri cows and on high-yielding dairy cattle in Europe and elsewhere as reported by meta-analytical data (22 experimentations). Milk samples were collected from 14 Kouri dairy cows in dry season (March to June) and fatty acids (FA) were determined by gas chromatography. Overall, 32 FA have been identified. Kouri showed lower values (P pastures by Kouri cows.

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

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

Thyroid lesions in patients with acromegaly - case-control study and update to the meta-analysis.

Science.gov (United States)

Woliński, Kosma; Stangierski, Adam; Gurgul, Edyta; Bromińska, Barbara; Czarnywojtek, Agata; Lodyga, Martha; Ruchała, Marek

2017-01-01

Acromegaly results from oversecretion of growth hormone and subsequently insulin growth factor-1. According to some authors, the disease can cause increased prevalence of nodular goitre and thyroid cancer (TC). However, the number of studies comparing acromegalic patients with control groups is low. We aimed to assess the prevalence of thyroid lesions in patients with acromegaly in comparison to an age- and sex-matched control group and to update the meta-analysis previously performed in our department by the same authors. We searched medical documentation of patients with acromegaly treated in our department between 2003 and 2013. The prevalence of thyroid abnormalities was compared with the group of patients with hormonally inactive adrenal incidentalomas. To perform the meta-analytic part of the paper we also searched ten databases to find relevant papers. Two hundred and five patients with acromegaly and 184 patients with incidentalomas were included. Any thyroid lesions were present in 77.6% of patients with acromegaly vs. 63.0% with incidentalomas (p = 0.002), multinodular goitre - 66.8% vs. 47.8% (p = 0.0002), and TC- 5.4% vs. 2.7% (p = 0.21) respectively. For thyroid lesions the pooled odds ratio (OR) was 3.1 (95% confidence interval [CI] 1.8-5.5), and for TCs the OR was 4.5 (95% CI 1.9-10.3). According to our results thyroid lesions were significantly more common in patients with acromegaly; in case of TC the difference was not significant. The updated meta-analysis showed significantly increased prevalence of both disorders. In conclusion, systematic thyroid examination should be an important part of follow-up in case of acromegalic patients. (Endokrynol Pol 2017; 68 (1): 2-6).

Interval estimation of the overall treatment effect in a meta-analysis of a few small studies with zero events

NARCIS (Netherlands)

Pateras, Konstantinos; Nikolakopoulos, Stavros; Mavridis, Dimitris; Roes, Kit C.B.

2018-01-01

When a meta-analysis consists of a few small trials that report zero events, accounting for heterogeneity in the (interval) estimation of the overall effect is challenging. Typically, we predefine meta-analytical methods to be employed. In practice, data poses restrictions that lead to deviations

"Cancer-Related Fatigue: A Systematic and Meta-Analytic Review of Nonpharmacological Therapies for Cancer Patients:" Correction to Kangas, Bovbjerg, and Montgomery (2008)

Science.gov (United States)

Kangas, Maria; Bovbjerg, Dana H.; Montgomery, Guy H.

2009-01-01

Reports an error in "Cancer-related fatigue: A systematic and meta-analytic review of non-pharmacological therapies for cancer patients" by Maria Kangas, Dana H. Bovbjerg and Guy H. Montgomery (Psychological Bulletin, 2008[Sep], Vol 134[5], 700-741). The URL to the Supplemental Materials for the article is listed incorrectly in two places in the…

A meta-analytic review of moral licensing.

Science.gov (United States)

Blanken, Irene; van de Ven, Niels; Zeelenberg, Marcel

2015-04-01

Moral licensing refers to the effect that when people initially behave in a moral way, they are later more likely to display behaviors that are immoral, unethical, or otherwise problematic. We provide a state-of-the-art overview of moral licensing by conducting a meta-analysis of 91 studies (7,397 participants) that compare a licensing condition with a control condition. Based on this analysis, the magnitude of the moral licensing effect is estimated to be a Cohen's d of 0.31. We tested potential moderators and found that published studies tend to have larger moral licensing effects than unpublished studies. We found no empirical evidence for other moderators that were theorized to be of importance. The effect size estimate implies that studies require many more participants to draw solid conclusions about moral licensing and its possible moderators. © 2015 by the Society for Personality and Social Psychology, Inc.

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.

Meta-analyses of workplace physical activity and dietary behaviour interventions on weight outcomes

NARCIS (Netherlands)

Verweij, L.M.; Coffeng, J.; Mechelen, W. van; Proper, K.I.

2011-01-01

This meta-analytic review critically examines the effectiveness of workplace interventions targeting physical activity, dietary behaviour or both on weight outcomes. Data could be extracted from 22 studies published between 1980 and November 2009 for meta-analyses. The GRADE approach was used to

How to Make Nothing Out of Something: Analyses of the Impact of Study Sampling and Statistical Interpretation in Misleading Meta-Analytic Conclusions

Directory of Open Access Journals (Sweden)

Michael Robert Cunningham

2016-10-01

Full Text Available The limited resource model states that self-control is governed by a relatively finite set of inner resources on which people draw when exerting willpower. Once self-control resources have been used up or depleted, they are less available for other self-control tasks, leading to a decrement in subsequent self-control success. The depletion effect has been studied for over 20 years, tested or extended in more than 600 studies, and supported in an independent meta-analysis (Hagger, Wood, Stiff, and Chatzisarantis, 2010. Meta-analyses are supposed to reduce bias in literature reviews. Carter, Kofler, Forster, and McCullough’s (2015 meta-analysis, by contrast, included a series of questionable decisions involving sampling, methods, and data analysis. We provide quantitative analyses of key sampling issues: exclusion of many of the best depletion studies based on idiosyncratic criteria and the emphasis on mini meta-analyses with low statistical power as opposed to the overall depletion effect. We discuss two key methodological issues: failure to code for research quality, and the quantitative impact of weak studies by novice researchers. We discuss two key data analysis issues: questionable interpretation of the results of trim and fill and funnel plot asymmetry test procedures, and the use and misinterpretation of the untested Precision Effect Test [PET] and Precision Effect Estimate with Standard Error (PEESE procedures. Despite these serious problems, the Carter et al. meta-analysis results actually indicate that there is a real depletion effect – contrary to their title.

Predicting organic food consumption: A meta-analytic structural equation model based on the theory of planned behavior.

Science.gov (United States)

Scalco, Andrea; Noventa, Stefano; Sartori, Riccardo; Ceschi, Andrea

2017-05-01

During the last decade, the purchase of organic food within a sustainable consumption context has gained momentum. Consequently, the amount of research in the field has increased, leading in some cases to discrepancies regarding both methods and results. The present review examines those works that applied the theory of planned behavior (TPB; Ajzen, 1991) as a theoretical framework in order to understand and predict consumers' motivation to buy organic food. A meta-analysis has been conducted to assess the strength of the relationships between attitude, subjective norms, perceived behavioral control, and intention, as well as between intention and behavior. Results confirm the major role played by individual attitude in shaping buying intention, followed by subjective norms and perceived behavioral control. Intention-behavior shows a large effect size, few studies however explicitly reported such an association. Furthermore, starting from a pooled correlation matrix, a meta-analytic structural equation model has been applied to jointly evaluate the strength of the relationships among the factors of the original model. Results suggest the robustness of the TPB model. In addition, mediation analysis indicates a potential direct effect from subjective norms to individual attitude in the present context. Finally, some issues regarding methodological aspects of the application of the TPB within the context of organic food are discussed for further research developments. Copyright © 2017 Elsevier Ltd. All rights reserved.

How important are work-family support policies? A meta-analytic investigation of their effects on employee outcomes.

Science.gov (United States)

Butts, Marcus M; Casper, Wendy J; Yang, Tae Seok

2013-01-01

This meta-analysis examines relationships between work-family support policies, which are policies that provide support for dependent care responsibilities, and employee outcomes by developing a conceptual model detailing the psychological mechanisms through which policy availability and use relate to work attitudes. Bivariate results indicated that availability and use of work-family support policies had modest positive relationships with job satisfaction, affective commitment, and intentions to stay. Further, tests of differences in effect sizes showed that policy availability was more strongly related to job satisfaction, affective commitment, and intentions to stay than was policy use. Subsequent meta-analytic structural equation modeling results indicated that policy availability and use had modest effects on work attitudes, which were partially mediated by family-supportive organization perceptions and work-to-family conflict, respectively. Additionally, number of policies and sample characteristics (percent women, percent married-cohabiting, percent with dependents) moderated the effects of policy availability and use on outcomes. Implications of these findings and directions for future research on work-family support policies are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

The Effects of Classroom Interventions on Off-Task and Disruptive Classroom Behavior in Children with Symptoms of Attention-Deficit/Hyperactivity Disorder : A Meta-Analytic Review

NARCIS (Netherlands)

Gaastra, Geraldina F; Groen, Yvonne; Tucha, Lara; Tucha, Oliver

2016-01-01

Children with attention-deficit/hyperactivity disorder (ADHD) often exhibit problem behavior in class, which teachers often struggle to manage due to a lack of knowledge and skills to use classroom management strategies. The aim of this meta-analytic review was to determine the effectiveness of

Transfer of test-enhanced learning: Meta-analytic review and synthesis.

Science.gov (United States)

Pan, Steven C; Rickard, Timothy C

2018-05-07

Attempting recall of information from memory, as occurs when taking a practice test, is one of the most potent training techniques known to learning science. However, does testing yield learning that transfers to different contexts? In the present article, we report the findings of the first comprehensive meta-analytic review into that question. Our review encompassed 192 transfer effect sizes extracted from 122 experiments and 67 published and unpublished articles (N = 10,382) that together comprise more than 40 years of research. A random-effects model revealed that testing can yield transferrable learning as measured relative to a nontesting reexposure control condition (d = 0.40, 95% CI [0.31, 0.50]). That transfer of learning is greatest across test formats, to application and inference questions, to problems involving medical diagnoses, and to mediator and related word cues; it is weakest to rearranged stimulus-response items, to untested materials seen during initial study, and to problems involving worked examples. Moderator analyses further indicated that response congruency and elaborated retrieval practice, as well as initial test performance, strongly influence the likelihood of positive transfer. In two assessments for publication bias using PET-PEESE and various selection methods, the moderator effect sizes were minimally affected. However, the intercept predictions were substantially reduced, often indicating no positive transfer when none of the aforementioned moderators are present. Overall, our results motivate a three-factor framework for transfer of test-enhanced learning and have practical implications for the effective use of practice testing in educational and other training contexts. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Andrews’ Principles of Risk, Need, and Responsivity as Applied in Drug Abuse Treatment Programs: Meta-Analysis of Crime and Drug Use Outcomes

Science.gov (United States)

Prendergast, Michael L.; Pearson, Frank S.; Podus, Deborah; Hamilton, Zachary K.; Greenwell, Lisa

2013-01-01

Objectives The purpose of the present meta-analysis was to answer the question: Can the Andrews principles of risk, needs, and responsivity, originally developed for programs that treat offenders, be extended to programs that treat drug abusers? Methods Drawing from a dataset that included 243 independent comparisons, we conducted random-effects meta-regression and ANOVA-analog meta-analyses to test the Andrews principles by averaging crime and drug use outcomes over a diverse set of programs for drug abuse problems. Results For crime outcomes, in the meta-regressions the point estimates for each of the principles were substantial, consistent with previous studies of the Andrews principles. There was also a substantial point estimate for programs exhibiting a greater number of the principles. However, almost all of the 95% confidence intervals included the zero point. For drug use outcomes, in the meta-regressions the point estimates for each of the principles was approximately zero; however, the point estimate for programs exhibiting a greater number of the principles was somewhat positive. All of the estimates for the drug use principles had confidence intervals that included the zero point. Conclusions This study supports previous findings from primary research studies targeting the Andrews principles that those principles are effective in reducing crime outcomes, here in meta-analytic research focused on drug treatment programs. By contrast, programs that follow the principles appear to have very little effect on drug use outcomes. Primary research studies that experimentally test the Andrews principles in drug treatment programs are recommended. PMID:24058325

Gender differences in emotion expression in children: a meta-analytic review.

Science.gov (United States)

Chaplin, Tara M; Aldao, Amelia

2013-07-01

Emotion expression is an important feature of healthy child development that has been found to show gender differences. However, there has been no empirical review of the literature on gender and facial, vocal, and behavioral expressions of different types of emotions in children. The present study constitutes a comprehensive meta-analytic review of gender differences and moderators of differences in emotion expression from infancy through adolescence. We analyzed 555 effect sizes from 166 studies with a total of 21,709 participants. Significant but very small gender differences were found overall, with girls showing more positive emotions (g = -.08) and internalizing emotions (e.g., sadness, anxiety, sympathy; g = -.10) than boys, and boys showing more externalizing emotions (e.g., anger; g = .09) than girls. Notably, gender differences were moderated by age, interpersonal context, and task valence, underscoring the importance of contextual factors in gender differences. Gender differences in positive emotions were more pronounced with increasing age, with girls showing more positive emotions than boys in middle childhood (g = -.20) and adolescence (g = -.28). Boys showed more externalizing emotions than girls at toddler/preschool age (g = .17) and middle childhood (g = .13) and fewer externalizing emotions than girls in adolescence (g = -.27). Gender differences were less pronounced with parents and were more pronounced with unfamiliar adults (for positive emotions) and with peers/when alone (for externalizing emotions). Our findings of gender differences in emotion expression in specific contexts have important implications for gender differences in children's healthy and maladaptive development. 2013 APA, all rights reserved

Gender Differences in Emotion Expression in Children: A Meta-Analytic Review

Science.gov (United States)

Chaplin, Tara M.; Aldao, Amelia

2012-01-01

Emotion expression is an important feature of healthy child development that has been found to show gender differences. However, there has been no empirical review of the literature on gender and facial, vocal, and behavioral expressions of different types of emotions in children. The present study constitutes a comprehensive meta-analytic review of gender differences, and moderators of differences, in emotion expression from infancy through adolescence. We analyzed 555 effect sizes from 166 studies with a total of 21,709 participants. Significant, but very small, gender differences were found overall, with girls showing more positive emotions (g = −.08) and internalizing emotions (e.g., sadness, anxiety, sympathy; g = −.10) than boys, and boys showing more externalizing emotions (e.g., anger; g = .09) than girls. Notably, gender differences were moderated by age, interpersonal context, and task valence, underscoring the importance of contextual factors in gender differences. Gender differences in positive emotions were more pronounced with increasing age, with girls showing more positive emotions than boys in middle childhood (g = −.20) and adolescence (g = −.28). Boys showed more externalizing emotions than girls at toddler/preschool age (g = .17) and middle childhood (g = .13) and fewer externalizing emotions than girls in adolescence (g = −.27). Gender differences were less pronounced with parents and were more pronounced with unfamiliar adults (for positive emotions) and with peers/when alone (for externalizing emotions). Our findings of gender differences in emotion expression in specific contexts have important implications for gender differences in children’s healthy and maladaptive development. PMID:23231534

Understanding the physical attractiveness literature: Qualitative reviews versus meta-analysis.

Science.gov (United States)

Feingold, Alan

2017-01-01

The target article is a qualitative review of selected findings in the physical attractiveness literature. This commentary explains why the meta-analytic approach, frequently used by other attractiveness reviewers, is preferable for drawing unbiased conclusions about the effects of attractiveness. The article's main contribution is affording a foundation for subsequent meta-analysis of the studies discussed in a subjective fashion.

"A joke a day keeps the doctor away?" Meta-analytical evidence of differential associations of habitual humor styles with mental health.

Science.gov (United States)

Schneider, Martha; Voracek, Martin; Tran, Ulrich S

2018-02-12

Humor and mental health are interconnected as is evidenced by a large number of studies. However, associations are only small and inconsistent as the operationalization of humor poses a methodological challenge. The Humor Styles Questionnaire (HSQ) differentiates four humor styles that might be beneficial or harmful to mental health. The aim of the present study was to meta-analytically aggregate studies using the HSQ to assess the associations of different humor styles with four areas of mental health (self-esteem, life satisfaction, optimism, depression). An extensive electronic database literature search identified 37 studies that reported correlations between the HSQ scales and the four areas of mental health in 45 independent samples (total N = 12,734). In total, 16 meta-analyses were conducted. Moderating effects of participant age, sex, and geographic region were examined via subgroup analyses and meta-regression. Humor styles differed in terms of their associations with mental health. Health-promoting humor styles were overall positively correlated with mental health (small-to-medium effect sizes). Self-defeating humor was overall negatively correlated with mental health. Aggressive humor was overall unrelated with mental health. Moderator analyses suggested geographic differences (Eastern vs. Western samples) and sex differences for some of these associations. Fostering specific humor styles may be beneficial for mental health. In addition, observing the habitual use of humor styles might help therapists to develop a better understanding of their clients. Differences in the utilization and the correlates of humor styles in Eastern and Western societies, and sex differences, need to be addressed in future research. © 2018 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Effectiveness of the Incredible Years parent training to modify disruptive and prosocial child behavior: a meta-analytic review.

Science.gov (United States)

Menting, Ankie T A; Orobio de Castro, Bram; Matthys, Walter

2013-12-01

The present meta-analytic review examined effectiveness of the Incredible Years parent training (IYPT) regarding disruptive and prosocial child behavior, and aimed to explain variability in intervention outcomes. Fifty studies, in which an intervention group receiving the IYPT was compared to a comparison group immediately after intervention, were included in the analyses. Results showed that the IYPT is an effective intervention. Positive effects for distinct outcomes and distinct informants were found, including a mean effect size of d=.27 concerning disruptive child behavior across informants. For parental report, treatment studies were associated with larger effects (d=.50) than indicated (d=.20) and selective (d=.13) prevention studies. Furthermore, initial severity of child behavior revealed to be the strongest predictor of intervention effects, with larger effects for studies including more severe cases. Findings indicate that the IYPT is successful in improving child behavior in a diverse range of families, and that the parent program may be considered well-established. © 2013.

A Meta-Analytic Approach to Examining the Correlation Between Religion/Spirituality and Mental Health in Cancer

Science.gov (United States)

Salsman, John M.; Pustejovsky, James E.; Jim, Heather S.L.; Munoz, Alexis R.; Merluzzi, Thomas V.; George, Login; Park, Crystal L.; Danhauer, Suzanne C.; Sherman, Allen C.; Snyder, Mallory A.; Fitchett, George

2015-01-01

Purpose Religion and spirituality (R/S) are patient-centered factors and often resources for managing the emotional sequelae of the cancer experience. Studies investigating the relationship between R/S (e.g., beliefs, experiences, coping) and mental health (e.g., depression, anxiety, well-being) in cancer have used very heterogeneous measures, with correspondingly inconsistent results. A meaningful synthesis of these findings has been lacking; thus, the purpose of this study was to conduct a meta-analysis of the research on R/S and mental health. Methods Four electronic databases were systematically reviewed and 2,073 abstracts met initial selection criteria. Reviewer pairs applied standardized coding schemes to extract correlational indices of the relationship between R/S and mental health. A total of 617 effect sizes from 148 eligible studies were synthesized using meta-analytic generalized estimating equations; subgroup analyses were performed to examine moderators of effects. Results The estimated mean correlation (Fisher z) was 0.19 (95% CI 0.16–0.23), which varied as a function of R/S dimension: affective, z=0.38 (95% CI 0.33-0.43); behavioral, z=0.03 (95% CI -0.02-0.08); cognitive, z=0.10 (95% CI 0.06-0.14); and ‘other,’ z=0.08 (95% CI 0.03-0.13). Aggregate, study-level demographic and clinical factors were not predictive of the relationship between R/S and mental health. There was little indication of publication or reporting biases. Conclusions The relationship between R/S and mental health is generally a positive one. The strength of that relationship is modest and varies as a function of R/S dimensions and mental health domains assessed. Identification of optimal R/S measures and more sophisticated methodological approaches are needed to advance research. PMID:26258536

Depression and Anxiety Prevention Based on Cognitive Behavioral Therapy for At-Risk Adolescents: A Meta-Analytic Review

Directory of Open Access Journals (Sweden)

Sanne P. A. Rasing

2017-06-01

Full Text Available Depression and anxiety disorders are among the most common mental disorders during adolescence. During this life phase, the incidence of these clinical disorders rises dramatically, and even more adolescents suffer from symptoms of depression or anxiety that are just below the clinical threshold. Both clinical and subclinical levels of depression or anxiety symptoms are related to decreased functioning in various areas, such as social and academic functioning. Prevention of depression and anxiety in adolescents is therefore imperative. We conducted a meta-analytic review of the effects of school-based and community-based prevention programs that are based on cognitive behavioral therapy with the primary goal preventing depression, anxiety, or both in high risk adolescents. Articles were obtained by searching databases and hand searching reference lists of relevant articles and reviews. The selection process yielded 32 articles in the meta-analyses. One article reported on two studies and three articles reported on both depression and anxiety. This resulted in a total of 36 studies, 23 on depression and 13 on anxiety. For depression prevention aimed at high risk adolescents, meta-analysis showed a small effect of prevention programs directly after the intervention, but no effect at 3–6 months and at 12 months follow-up. For anxiety prevention aimed at high risk adolescents, no short-term effect was found, nor at 12 months follow-up. Three to six months after the preventive intervention, symptoms of anxiety were significantly decreased. Although effects on depression and anxiety symptoms were small and temporary, current findings cautiously suggest that depression and anxiety prevention programs based on CBT might have small effects on mental health of adolescents. However, it also indicates that there is still much to be gained for prevention programs. Current findings and possibilities for future research are discussed in order to further

Neural Correlates of Psychotherapy in Anxiety and Depression: A Meta-Analysis

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Messina, Irene; Sambin, Marco; Palmieri, Arianna; Viviani, Roberto

2013-01-01

Several studies have used neuroimaging methods to identify neural change in brain networks associated to emotion regulation after psychotherapy of depression and anxiety. In the present work we adopted a meta-analytic technique specific to neuroimaging data to evaluate the consistence of empirical findings and assess models of therapy that have been proposed in the literature. Meta-analyses were conducted with the Activation Likelihood Estimation technique, which evaluates the overlap between foci of activation across studies. The analysis included 16 studies found in Pubmed (200 foci of activation and 193 patients). Separate meta-analyses were conducted on studies of 1) depression, post-traumatic stress disorder and panic disorder investigated with rest state metabolism (6 studies, 70 patients); 2) depression, post-traumatic stress disorder and panic disorder investigated with task-related activation studies (5 studies, 65 patients); 3) the previous studies considered jointly; and 4) phobias investigated with studies on exposure-related activation (5 studies, 57 patients). Studies on anxiety and depression gave partially consistent results for changes in the dorsomedial prefrontal cortex and in the posterior cingulated gyrus/precuneus. Several areas of change in the temporal lobes were also observed. Studies on the therapy of phobia were consistent with a reduction of activity in medial temporal areas. The cluster of change in the prefrontal cortex may refer to increased recruitment of control processes, as hypothesized by influential models of emotion regulation changes due to psychotherapy. However, not all areas associated with controlled emotion regulation were detected in the meta-analysis, while involvement of midline structures suggested changes in self-related information processing. Changes in phobia were consistent with reduced reactivity to phobic stimuli. PMID:24040309

Neural correlates of psychotherapy in anxiety and depression: a meta-analysis.

Directory of Open Access Journals (Sweden)

Irene Messina

Full Text Available Several studies have used neuroimaging methods to identify neural change in brain networks associated to emotion regulation after psychotherapy of depression and anxiety. In the present work we adopted a meta-analytic technique specific to neuroimaging data to evaluate the consistence of empirical findings and assess models of therapy that have been proposed in the literature. Meta-analyses were conducted with the Activation Likelihood Estimation technique, which evaluates the overlap between foci of activation across studies. The analysis included 16 studies found in Pubmed (200 foci of activation and 193 patients. Separate meta-analyses were conducted on studies of 1 depression, post-traumatic stress disorder and panic disorder investigated with rest state metabolism (6 studies, 70 patients; 2 depression, post-traumatic stress disorder and panic disorder investigated with task-related activation studies (5 studies, 65 patients; 3 the previous studies considered jointly; and 4 phobias investigated with studies on exposure-related activation (5 studies, 57 patients. Studies on anxiety and depression gave partially consistent results for changes in the dorsomedial prefrontal cortex and in the posterior cingulated gyrus/precuneus. Several areas of change in the temporal lobes were also observed. Studies on the therapy of phobia were consistent with a reduction of activity in medial temporal areas. The cluster of change in the prefrontal cortex may refer to increased recruitment of control processes, as hypothesized by influential models of emotion regulation changes due to psychotherapy. However, not all areas associated with controlled emotion regulation were detected in the meta-analysis, while involvement of midline structures suggested changes in self-related information processing. Changes in phobia were consistent with reduced reactivity to phobic stimuli.

Social relationships and cognitive decline: a systematic review and meta-analysis of longitudinal cohort studies.

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Kuiper, Jisca S; Zuidersma, Marij; Zuidema, Sytse U; Burgerhof, Johannes Gm; Stolk, Ronald P; Oude Voshaar, Richard C; Smidt, Nynke

2016-08-01

Although poor social relationships are assumed to contribute to cognitive decline, meta-analytic approaches have not been applied. Individual study results are mixed and difficult to interpret due to heterogeneity in measures of social relationships. We conducted a systematic review and meta-analysis to investigate the relation between poor social relationships and cognitive decline. MEDLINE, Embase and PsycINFO were searched for longitudinal cohort studies examining various aspects of social relationships and cognitive decline in the general population. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using random effects meta-analysis. Sources of heterogeneity were explored and likelihood of publication bias was assessed. We stratified analyses according to three aspects of social relationships: structural, functional and a combination of these. We identified 43 articles. Poor social relationships predicted cognitive decline; for structural (19 studies): pooled OR: 1.08 (95% CI: 1.05-1.11); functional (8 studies): pooled OR: 1.15 (95% CI: 1.00-1.32); and combined measures (7 studies): pooled OR: 1.12 (95% CI: 1.01-1.24). Meta-regression and subgroup analyses showed that the heterogeneity could be explained by the type of social relationship measurement and methodological quality of included studies. Despite heterogeneity in study design and measures, our meta-analyses show that multiple aspects of social relationships are associated with cognitive decline. As evidence for publication bias was found, the association might be overestimated and should therefore be interpreted with caution. Future studies are needed to better define the mechanisms underlying these associations. Potential causality of this prognostic association should be examined in future randomized controlled studies. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

A meta-analytic approach to examining the correlation between religion/spirituality and mental health in cancer.

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Salsman, John M; Pustejovsky, James E; Jim, Heather S L; Munoz, Alexis R; Merluzzi, Thomas V; George, Login; Park, Crystal L; Danhauer, Suzanne C; Sherman, Allen C; Snyder, Mallory A; Fitchett, George

2015-11-01

Religion and spirituality (R/S) are patient-centered factors and often are resources for managing the emotional sequelae of the cancer experience. Studies investigating the correlation between R/S (eg, beliefs, experiences, coping) and mental health (eg, depression, anxiety, well being) in cancer have used very heterogeneous measures and have produced correspondingly inconsistent results. A meaningful synthesis of these findings has been lacking; thus, the objective of this review was to conduct a meta-analysis of the research on R/S and mental health. Four electronic databases were systematically reviewed, and 2073 abstracts met initial selection criteria. Reviewer pairs applied standardized coding schemes to extract indices of the correlation between R/S and mental health. In total, 617 effect sizes from 148 eligible studies were synthesized using meta-analytic generalized estimating equations, and subgroup analyses were performed to examine moderators of effects. The estimated mean correlation (Fisher z) was 0.19 (95% confidence interval [CI], 0.16-0.23), which varied as a function of R/S dimensions: affective R/S (z = 0.38; 95% CI, 0.33-0.43), behavioral R/S (z = 0.03; 95% CI, -0.02-0.08), cognitive R/S (z = 0.10; 95% CI, 0.06-0.14), and 'other' R/S (z = 0.08; 95% CI, 0.03-0.13). Aggregate, study-level demographic and clinical factors were not predictive of the relation between R/S and mental health. There was little indication of publication or reporting biases. The correlation between R/S and mental health generally was positive. The strength of that correlation was modest and varied as a function of the R/S dimensions and mental health domains assessed. The identification of optimal R/S measures and more sophisticated methodological approaches are needed to advance research. © 2015 American Cancer Society.

Intrinsic motivation and extrinsic incentives jointly predict performance: a 40-year meta-analysis.

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Cerasoli, Christopher P; Nicklin, Jessica M; Ford, Michael T

2014-07-01

More than 4 decades of research and 9 meta-analyses have focused on the undermining effect: namely, the debate over whether the provision of extrinsic incentives erodes intrinsic motivation. This review and meta-analysis builds on such previous reviews by focusing on the interrelationship among intrinsic motivation, extrinsic incentives, and performance, with reference to 2 moderators: performance type (quality vs. quantity) and incentive contingency (directly performance-salient vs. indirectly performance-salient), which have not been systematically reviewed to date. Based on random-effects meta-analytic methods, findings from school, work, and physical domains (k = 183, N = 212,468) indicate that intrinsic motivation is a medium to strong predictor of performance (ρ = .21-45). The importance of intrinsic motivation to performance remained in place whether incentives were presented. In addition, incentive salience influenced the predictive validity of intrinsic motivation for performance: In a "crowding out" fashion, intrinsic motivation was less important to performance when incentives were directly tied to performance and was more important when incentives were indirectly tied to performance. Considered simultaneously through meta-analytic regression, intrinsic motivation predicted more unique variance in quality of performance, whereas incentives were a better predictor of quantity of performance. With respect to performance, incentives and intrinsic motivation are not necessarily antagonistic and are best considered simultaneously. Future research should consider using nonperformance criteria (e.g., well-being, job satisfaction) as well as applying the percent-of-maximum-possible (POMP) method in meta-analyses. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Improving accuracy and power with transfer learning using a meta-analytic database.

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Schwartz, Yannick; Varoquaux, Gaël; Pallier, Christophe; Pinel, Philippe; Poline, Jean-Baptiste; Thirion, Bertrand

2012-01-01

Typical cohorts in brain imaging studies are not large enough for systematic testing of all the information contained in the images. To build testable working hypotheses, investigators thus rely on analysis of previous work, sometimes formalized in a so-called meta-analysis. In brain imaging, this approach underlies the specification of regions of interest (ROIs) that are usually selected on the basis of the coordinates of previously detected effects. In this paper, we propose to use a database of images, rather than coordinates, and frame the problem as transfer learning: learning a discriminant model on a reference task to apply it to a different but related new task. To facilitate statistical analysis of small cohorts, we use a sparse discriminant model that selects predictive voxels on the reference task and thus provides a principled procedure to define ROIs. The benefits of our approach are twofold. First it uses the reference database for prediction, i.e., to provide potential biomarkers in a clinical setting. Second it increases statistical power on the new task. We demonstrate on a set of 18 pairs of functional MRI experimental conditions that our approach gives good prediction. In addition, on a specific transfer situation involving different scanners at different locations, we show that voxel selection based on transfer learning leads to higher detection power on small cohorts.

Video games do affect social outcomes: a meta-analytic review of the effects of violent and prosocial video game play.

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Greitemeyer, Tobias; Mügge, Dirk O

2014-05-01

Whether video game play affects social behavior is a topic of debate. Many argue that aggression and helping are affected by video game play, whereas this stance is disputed by others. The present research provides a meta-analytical test of the idea that depending on their content, video games do affect social outcomes. Data from 98 independent studies with 36,965 participants revealed that for both violent video games and prosocial video games, there was a significant association with social outcomes. Whereas violent video games increase aggression and aggression-related variables and decrease prosocial outcomes, prosocial video games have the opposite effects. These effects were reliable across experimental, correlational, and longitudinal studies, indicating that video game exposure causally affects social outcomes and that there are both short- and long-term effects.

Meta-analysis as Statistical and Analytical Method of Journal's Content Scientific Evaluation.

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Masic, Izet; Begic, Edin

2015-02-01

A meta-analysis is a statistical and analytical method which combines and synthesizes different independent studies and integrates their results into one common result. Analysis of the journals "Medical Archives", "Materia Socio Medica" and "Acta Informatica Medica", which are located in the most eminent indexed databases of the biomedical milieu. The study has retrospective and descriptive character, and included the period of the calendar year 2014. Study included six editions of all three journals (total of 18 journals). In this period was published a total of 291 articles (in the "Medical Archives" 110, "Materia Socio Medica" 97, and in "Acta Informatica Medica" 84). The largest number of articles was original articles. Small numbers have been published as professional, review articles and case reports. Clinical events were most common in the first two journals, while in the journal "Acta Informatica Medica" belonged to the field of medical informatics, as part of pre-clinical medical disciplines. Articles are usually required period of fifty to fifty nine days for review. Articles were received from four continents, mostly from Europe. The authors are most often from the territory of Bosnia and Herzegovina, then Iran, Kosovo and Macedonia. The number of articles published each year is increasing, with greater participation of authors from different continents and abroad. Clinical medical disciplines are the most common, with the broader spectrum of topics and with a growing number of original articles. Greater support of the wider scientific community is needed for further development of all three of the aforementioned journals.

Reward Devaluation: Dot-Probe Meta-Analytic Evidence of Avoidance of Positive Information in Depressed Persons

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Winer, E. Samuel; Salem, Taban

2015-01-01

Cognitive theories of depression and anxiety have traditionally emphasized the role of attentional biases in the processing of negative information. The dot-probe task has been widely used to study this phenomenon. Recent findings suggest that biased processing of positive information might also be an important aspect of developing psychopathological symptoms. However, despite some evidence suggesting persons with symptoms of depression and anxiety may avoid positive information, many dot-probe studies have produced null findings. The present review used conventional and novel meta-analytic methods to evaluate dot-probe attentional biases away from positive information and, for comparison, toward negative information, in depressed and anxious individuals. Results indicated that avoidance of positive information is a real effect exhibiting substantial evidential value among persons experiencing psychopathology, with individuals evidencing primary symptoms of depression clearly demonstrating this effect. Different theoretical explanations for these findings are evaluated, including those positing threat-processing structures, even-handedness, self-regulation, and reward devaluation, with the novel theory of reward devaluation emphasized and expanded. These novel findings and theory suggest that avoidance of prospective reward helps to explain the cause and sustainability of depressed states. Suggestions for future research and methodological advances are discussed. PMID:26619211

A meta-study of qualitative research examining determinants of children's independent active free play.

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Lee, Homan; Tamminen, Katherine A; Clark, Alexander M; Slater, Linda; Spence, John C; Holt, Nicholas L

2015-01-24

To produce a meta-study by completing a systematic review of qualitative research examining determinants of independent active free play in children. Following systematic electronic and manual searches and application of inclusion/exclusion criteria, 46 studies were retained and subjected to meta-method, meta-theory, and meta-data analyses, followed by a final meta-synthesis. Identified determinants of independent active free play were child characteristics (age, competence, and gender), parental restrictions (safety concerns and surveillance), neighborhood and physical environment (fewer children to play with, differences in preferences for play spaces between parents and children, accessibility and proximity, and maintenance), societal changes (reduced sense of community, good parenting ideal, changing roles of parents, privatization of playtime and play spaces), and policy issues (need to give children voice). An ecological model depicting these factors, and the relationships therein, was created. This comprehensive meta-study helps establish a knowledge base for children's independent active free play research by synthesizing a previously fragmented set of studies. Parents' perceived safety concerns are the primary barrier to children's active free play. These safety concerns are moderated by child-level factors (age, competence, gender) and broader social issues. Interventions should focus on community-level solutions that include children's perspectives. From a methods perspective, the reviewed studies used a range of data collection techniques, but methodological details were often inadequately reported. The theoretical sophistication of research in this area could be improved. To this end, the synthesis reported in this study provides a framework for guiding future research.

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

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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.

Dictator games: A meta study

OpenAIRE

Engel, Christoph

2010-01-01

Over the last 25 years, more than a hundred dictator game experiments have been published. This meta study summarizes the evidence. Exploiting the fact that most experiments had to fix parameters they did not intend to test, in multiple regression the meta study is able to assess the effect of single manipulations, controlling for a host of alternative explanatory factors. The resulting rich dataset also provides a testbed for comparing alternative specifications of the statistical model for ...

Food and drug cues activate similar brain regions: a meta-analysis of functional MRI studies.

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Tang, D W; Fellows, L K; Small, D M; Dagher, A

2012-06-06

In healthy individuals, food cues can trigger hunger and feeding behavior. Likewise, smoking cues can trigger craving and relapse in smokers. Brain imaging studies report that structures involved in appetitive behaviors and reward, notably the insula, striatum, amygdala and orbital frontal cortex, tend to be activated by both visual food and smoking cues. Here, by carrying out a meta-analysis of human neuro-imaging studies, we investigate the neural network activated by: 1) food versus neutral cues (14 studies, 142 foci) 2) smoking versus neutral cues (15 studies, 176 foci) 3) smoking versus neutral cues when correlated with craving scores (7 studies, 108 foci). PubMed was used to identify cue-reactivity imaging studies that compared brain response to visual food or smoking cues to neutral cues. Fourteen articles were identified for the food meta-analysis and fifteen articles were identified for the smoking meta-analysis. Six articles were identified for the smoking cue correlated with craving analysis. Meta-analyses were carried out using activation likelihood estimation. Food cues were associated with increased blood oxygen level dependent (BOLD) response in the left amygdala, bilateral insula, bilateral orbital frontal cortex, and striatum. Smoking cues were associated with increased BOLD signal in the same areas, with the exception of the insula. However, the smoking meta-analysis of brain maps correlating cue-reactivity with subjective craving did identify the insula, suggesting that insula activation is only found when craving levels are high. The brain areas identified here are involved in learning, memory and motivation, and their cue-induced activity is an index of the incentive salience of the cues. Using meta-analytic techniques to combine a series of studies, we found that food and smoking cues activate comparable brain networks. There is significant overlap in brain regions responding to conditioned cues associated with natural and drug rewards

Meta-Analysis for Sociology – A Measure-Driven Approach

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Roelfs, David J.; Shor, Eran; Falzon, Louise; Davidson, Karina W.; Schwartz, Joseph E.

2013-01-01

Meta-analytic methods are becoming increasingly important in sociological research. In this article we present an approach for meta-analysis which is especially helpful for sociologists. Conventional approaches to meta-analysis often prioritize “concept-driven” literature searches. However, in disciplines with high theoretical diversity, such as sociology, this search approach might constrain the researcher’s ability to fully exploit the entire body of relevant work. We explicate a “measure-driven” approach, in which iterative searches and new computerized search techniques are used to increase the range of publications found (and thus the range of possible analyses) and to traverse time and disciplinary boundaries. We demonstrate this measure-driven search approach with two meta-analytic projects, examining the effects of various social variables on all-cause mortality. PMID:24163498

Breast implants and the risk of breast cancer: a meta-analysis of cohort studies.

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Noels, Eline C; Lapid, Oren; Lindeman, Jan H N; Bastiaannet, Esther

2015-01-01

The popularity of cosmetic breast augmentation and the incidence of breast cancer have been increasing worldwide. It has been hypothesized that the risk of breast cancer may be greater among patients who have undergone cosmetic breast implantation. The authors performed a meta-analysis of the available literature on the risk of breast cancer among women with cosmetic breast implants. The study was designed as a meta-analysis of observational studies. A systematic search of the English literature (published by August 28, 2013) was conducted in PubMed and EMBASE. Eligible reports were those that included relative risk (RR; the increased or decreased risk of breast cancer associated with breast implants) or the standardized incidence ratio (SIR) of the observed number of cases of breast cancer to the expected number of cases among patients that previously underwent cosmetic breast augmentation. Seventeen studies representing 7 cohorts were selected. Some of these were follow-up reports of previously published studies; in such cases, only the most recent reports were included in the meta-analysis. Summary SIR and RR rates and the corresponding 95% confidence intervals (CIs) were calculated with a random-effects (SIR) or fixed-effects (RR) model. The overall SIR estimate was 0.69 (95% CI, 0.56-0.85), and the overall RR, based on 4 studies, was 0.63 (95% CI, 0.56-0.71). Finding of this meta-analysis suggest that women who have undergone cosmetic breast implantation do not have an increased risk of breast cancer. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Association between intrusive negative autobiographical memories and depression: A meta-analytic investigation.

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Mihailova, Stella; Jobson, Laura

2018-02-23

The study investigated several associations between depression and intrusive negative autobiographical memories. A systematic literature search identified 23 eligible studies (N = 2,582), which provided 59 effect sizes. Separate meta-analyses indicated that depression was moderately, positively associated with intrusive memory frequency, memory distress, maladaptive memory appraisals, memory avoidance, and memory rumination. Intrusive memory vividness was not significantly associated with depression. There were insufficient data to examine the relationship between depression and memory vantage perspective. Between-study heterogeneity was high for intrusive memory frequency and memory avoidance, and the percentage of females in studies significantly moderated the relationship between these variables and depression. An additional exploratory meta-analysis (3 studies; N = 257) indicated that intrusive memories were experienced more frequently by those with posttraumatic stress disorder than those with depression. Overall, the findings suggest that intrusive memories warrant clinical attention as they may contribute to the maintenance of depressive symptomatology. Copyright © 2018 John Wiley & Sons, Ltd.

A methodological systematic review of what's wrong with meta-ethnography reporting.

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France, Emma F; Ring, Nicola; Thomas, Rebecca; Noyes, Jane; Maxwell, Margaret; Jepson, Ruth

2014-11-19

Syntheses of qualitative studies can inform health policy, services and our understanding of patient experience. Meta-ethnography is a systematic seven-phase interpretive qualitative synthesis approach well-suited to producing new theories and conceptual models. However, there are concerns about the quality of meta-ethnography reporting, particularly the analysis and synthesis processes. Our aim was to investigate the application and reporting of methods in recent meta-ethnography journal papers, focusing on the analysis and synthesis process and output. Methodological systematic review of health-related meta-ethnography journal papers published from 2012-2013. We searched six electronic databases, Google Scholar and Zetoc for papers using key terms including 'meta-ethnography.' Two authors independently screened papers by title and abstract with 100% agreement. We identified 32 relevant papers. Three authors independently extracted data and all authors analysed the application and reporting of methods using content analysis. Meta-ethnography was applied in diverse ways, sometimes inappropriately. In 13% of papers the approach did not suit the research aim. In 66% of papers reviewers did not follow the principles of meta-ethnography. The analytical and synthesis processes were poorly reported overall. In only 31% of papers reviewers clearly described how they analysed conceptual data from primary studies (phase 5, 'translation' of studies) and in only one paper (3%) reviewers explicitly described how they conducted the analytic synthesis process (phase 6). In 38% of papers we could not ascertain if reviewers had achieved any new interpretation of primary studies. In over 30% of papers seminal methodological texts which could have informed methods were not cited. We believe this is the first in-depth methodological systematic review of meta-ethnography conduct and reporting. Meta-ethnography is an evolving approach. Current reporting of methods, analysis and

A two-dimensional approach to relationship conflict: meta-analytic findings.

Science.gov (United States)

Woodin, Erica M

2011-06-01

This meta-analysis of 64 studies (5,071 couples) used a metacoding system to categorize observed couple conflict behaviors into categories differing in terms of valence (positive to negative) and intensity (high to low) and resulting in five behavioral categories: hostility, distress, withdrawal, problem solving, and intimacy. Aggregate effect sizes indicated that women were somewhat more likely to display hostility, distress, and intimacy during conflict, whereas men were somewhat more likely to display withdrawal and problem solving. Gender differences were of a small magnitude. For both men and women, hostility was robustly associated with lower relationship satisfaction (medium effect), distress and withdrawal were somewhat associated (small effect), and intimacy and problem solving were both closely associated with relationship satisfaction (medium effect). Effect sizes were moderated in several cases by study characteristics including year of publication, developmental period of the sample, recruitment design, duration of observed conflict, method used to induce conflict, and type of coding system used. Findings from this meta-analysis suggest that high-intensity conflict behaviors of both a positive and negative nature are important correlates of relationship satisfaction and underscore the relatively small gender differences in many conflict behaviors. 2011 APA, all rights reserved

Age differences in the effect of framing on risky choice: A meta-analysis

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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

Unemployment Impairs Mental Health: Meta-Analyses

Science.gov (United States)

Paul, Karsten I.; Moser, Klaus

2009-01-01

The effect of unemployment on mental health was examined with meta-analytic methods across 237 cross-sectional and 87 longitudinal studies. The average overall effect size was d = 0.51 with unemployed persons showing more distress than employed persons. A significant difference was found for several indicator variables of mental health (mixed…

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

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

Identifying null meta-analyses that are ripe for updating

Directory of Open Access Journals (Sweden)

Fang Manchun

2003-07-01

Full Text Available Abstract Background As an increasingly large number of meta-analyses are published, quantitative methods are needed to help clinicians and systematic review teams determine when meta-analyses are not up to date. Methods We propose new methods for determining when non-significant meta-analytic results might be overturned, based on a prediction of the number of participants required in new studies. To guide decision making, we introduce the "new participant ratio", the ratio of the actual number of participants in new studies to the predicted number required to obtain statistical significance. A simulation study was conducted to study the performance of our methods and a real meta-analysis provides further evidence. Results In our three simulation configurations, our diagnostic test for determining whether a meta-analysis is out of date had sensitivity of 55%, 62%, and 49% with corresponding specificity of 85%, 80%, and 90% respectively. Conclusions Simulations suggest that our methods are able to detect out-of-date meta-analyses. These quick and approximate methods show promise for use by systematic review teams to help decide whether to commit the considerable resources required to update a meta-analysis. Further investigation and evaluation of the methods is required before they can be recommended for general use.

Phonological skills and their role in learning to read: a meta-analytic review.

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Melby-Lervåg, Monica; Lyster, Solveig-Alma Halaas; Hulme, Charles

2012-03-01

The authors report a systematic meta-analytic review of the relationships among 3 of the most widely studied measures of children's phonological skills (phonemic awareness, rime awareness, and verbal short-term memory) and children's word reading skills. The review included both extreme group studies and correlational studies with unselected samples (235 studies were included, and 995 effect sizes were calculated). Results from extreme group comparisons indicated that children with dyslexia show a large deficit on phonemic awareness in relation to typically developing children of the same age (pooled effect size estimate: -1.37) and children matched on reading level (pooled effect size estimate: -0.57). There were significantly smaller group deficits on both rime awareness and verbal short-term memory (pooled effect size estimates: rime skills in relation to age-matched controls, -0.93, and reading-level controls, -0.37; verbal short-term memory skills in relation to age-matched controls, -0.71, and reading-level controls, -0.09). Analyses of studies of unselected samples showed that phonemic awareness was the strongest correlate of individual differences in word reading ability and that this effect remained reliable after controlling for variations in both verbal short-term memory and rime awareness. These findings support the pivotal role of phonemic awareness as a predictor of individual differences in reading development. We discuss whether such a relationship is a causal one and the implications of research in this area for current approaches to the teaching of reading and interventions for children with reading difficulties.

A Meta-Analysis of Acculturation/Enculturation and Mental Health

Science.gov (United States)

Yoon, Eunju; Chang, Chih-Ting; Kim, Soyeon; Clawson, Angela; Cleary, Sarah Elizabeth; Hansen, Meghan; Bruner, John P.; Chan, Theresa K.; Gomes, Alexandrina M.

2013-01-01

This meta-analytic study examined the relationship among the constructs of acculturation, enculturation, and acculturation strategies (i.e., integration, assimilation, separation, marginalization), and mental health. Data from 325 studies (163 journal articles and 162 dissertation studies) were analyzed using a random-effects model, across a broad…

Incorporating uncertainty regarding applicability of evidence from meta-analyses into clinical decision making.

Science.gov (United States)

Kriston, Levente; Meister, Ramona

2014-03-01

Judging applicability (relevance) of meta-analytical findings to particular clinical decision-making situations remains challenging. We aimed to describe an evidence synthesis method that accounts for possible uncertainty regarding applicability of the evidence. We conceptualized uncertainty regarding applicability of the meta-analytical estimates to a decision-making situation as the result of uncertainty regarding applicability of the findings of the trials that were included in the meta-analysis. This trial-level applicability uncertainty can be directly assessed by the decision maker and allows for the definition of trial inclusion probabilities, which can be used to perform a probabilistic meta-analysis with unequal probability resampling of trials (adaptive meta-analysis). A case study with several fictitious decision-making scenarios was performed to demonstrate the method in practice. We present options to elicit trial inclusion probabilities and perform the calculations. The result of an adaptive meta-analysis is a frequency distribution of the estimated parameters from traditional meta-analysis that provides individually tailored information according to the specific needs and uncertainty of the decision maker. The proposed method offers a direct and formalized combination of research evidence with individual clinical expertise and may aid clinicians in specific decision-making situations. Copyright © 2014 Elsevier Inc. All rights reserved.

Vitamin D and depression: a systematic review and meta-analysis comparing studies with and without biological flaws.

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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.

Examining the Early Evidence for Self-Directed Marriage and Relationship Education: A Meta-Analytic Study

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McAllister, Shelece; Duncan, Stephen F.; Hawkins, Alan J.

2012-01-01

This meta-analysis examines the efficacy of self-directed marriage and relationship education (MRE) programs on relationship quality and communication skills. Programs combining traditional face-to-face learning with self-directed elements are also examined, and traditional programs' effectiveness is included as a comparison point. Sixteen studies…

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

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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.

Trial Sequential Analysis in systematic reviews with meta-analysis

Directory of Open Access Journals (Sweden)

Jørn Wetterslev

2017-03-01

systematic reviews with traditional meta-analyses can be reduced using Trial Sequential Analysis. Several empirical studies have demonstrated that the Trial Sequential Analysis provides better control of type I errors and of type II errors than the traditional naïve meta-analysis. Conclusions Trial Sequential Analysis represents analysis of meta-analytic data, with transparent assumptions, and better control of type I and type II errors than the traditional meta-analysis using naïve unadjusted confidence intervals.

Semantic priming without association: a meta-analytic review.

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Lucas, M

2000-12-01

A meta-analysis of 26 studies indicated that automatic semantic priming can occur without association. Priming did not vary substantially with differences in variables that affect automatic versus strategic processing, such as time spent processing the prime and target, relationship proportion, and task (except that average effects were smaller in the naming task). Although category coordinates were investigated in the majority of studies, synonyms, antonyms, and script relations also demonstrated priming; functional relations showed greater priming, and essential and perceptual relations showed less. The average effect size for semantic priming was smaller than that for associative priming, suggesting that there is an "associative boost" from adding an associative relationship to a semantic one. The implications of these findings for the modularity thesis and for models of semantic priming are discussed.

The Effects of Mindfulness-Based Interventions on Diabetes-Related Distress, Quality of Life, and Metabolic Control Among Persons with Diabetes: A Meta-Analytic Review.

Science.gov (United States)

Bogusch, Leah M; O'Brien, William H

2018-04-04

Mindfulness-based interventions (MBIs) have improved psychological outcomes for multiple chronic health conditions, including diabetes. A meta-analytic review of the literature was conducted on all located studies (n = 14) investigating MBIs that targeted diabetes-related distress (DRD) and diabetes-related outcomes among people with Type 1 and Type 2 diabetes. PsychInfo, PubMed, Medline, and Web of Science were searched for MBIs that were designed to improve DRD and other secondary outcomes, including quality of life and measures of metabolic control. A meta-analysis of these outcomes uncovered small-to-moderate effect sizes for intervention studies measuring pretreatment to posttreatment changes in DRD and metabolic control among treatment group participants. However, the pretreatment to follow-up comparisons for DRD and metabolic control were small and unreliable. For control groups, all pre-treatment to post-treatment and pre-treatment to follow-up comparisons were unreliable for all outcomes. A moderate effect size for treatment-control comparisons was found for intervention studies measuring quality of life outcomes at posttreatment, but not at follow-up comparisons. All other effect sizes for treatment-control comparisons were unreliable. Limitations and implications for MBIs among individuals with diabetes are discussed.

A Meta-analytic Comparison of Face-to-Face and Online Delivery in Ethics Instruction: The Case for a Hybrid Approach.

Science.gov (United States)

Todd, E Michelle; Watts, Logan L; Mulhearn, Tyler J; Torrence, Brett S; Turner, Megan R; Connelly, Shane; Mumford, Michael D

2017-12-01

Despite the growing body of literature on training in the responsible conduct of research, few studies have examined the effectiveness of delivery formats used in ethics courses (i.e., face-to-face, online, hybrid). The present effort sought to address this gap in the literature through a meta-analytic review of 66 empirical studies, representing 106 ethics courses and 10,069 participants. The frequency and effectiveness of 67 instructional and process-based content areas were also assessed for each delivery format. Process-based contents were best delivered face-to-face, whereas contents delivered online were most effective when restricted to compliance-based instructional contents. Overall, hybrid courses were found to be most effective, suggesting that ethics courses are best delivered using a blend of formats and content areas. Implications and recommendations for future development of ethics education courses in the sciences are discussed.

Prevalence and incidence of epilepsy: A systematic review and meta-analysis of international studies.

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Fiest, Kirsten M; Sauro, Khara M; Wiebe, Samuel; Patten, Scott B; Kwon, Churl-Su; Dykeman, Jonathan; Pringsheim, Tamara; Lorenzetti, Diane L; Jetté, Nathalie

2017-01-17

To review population-based studies of the prevalence and incidence of epilepsy worldwide and use meta-analytic techniques to explore factors that may explain heterogeneity between estimates. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses standards were followed. We searched MEDLINE and EMBASE for articles published on the prevalence or incidence of epilepsy since 1985. Abstract, full-text review, and data abstraction were conducted in duplicate. Meta-analyses and meta-regressions were used to explore the association between prevalence or incidence, age group, sex, country level income, and study quality. A total of 222 studies were included (197 on prevalence, 48 on incidence). The point prevalence of active epilepsy was 6.38 per 1,000 persons (95% confidence interval [95% CI] 5.57-7.30), while the lifetime prevalence was 7.60 per 1,000 persons (95% CI 6.17-9.38). The annual cumulative incidence of epilepsy was 67.77 per 100,000 persons (95% CI 56.69-81.03) while the incidence rate was 61.44 per 100,000 person-years (95% CI 50.75-74.38). The prevalence of epilepsy did not differ by age group, sex, or study quality. The active annual period prevalence, lifetime prevalence, and incidence rate of epilepsy were higher in low to middle income countries. Epilepsies of unknown etiology and those with generalized seizures had the highest prevalence. This study provides a comprehensive synthesis of the prevalence and incidence of epilepsy from published international studies and offers insight into factors that contribute to heterogeneity between estimates. Significant gaps (e.g., lack of incidence studies, stratification by age groups) were identified. Standardized reporting of future epidemiologic studies of epilepsy is needed. © 2016 American Academy of Neurology.

The Sleeper Effect in Persuasion: A Meta-Analytic Review

Science.gov (United States)

Kumkale, G. Tarcan; Albarracín, Dolores

2009-01-01

A meta-analysis of the available judgment and memory data on the sleeper effect in persuasion is presented. According to this effect, when people receive a communication associated with a discounting cue, such as a noncredible source, they are less persuaded immediately after exposure than they are later in time. Findings from this meta-analysis indicate that recipients of discounting cues were more persuaded over time when the message arguments and the cue had a strong initial impact. In addition, the increase in persuasion was stronger when recipients of discounting cues had higher ability or motivation to think about the message and received the discounting cue after the message. These results are discussed in light of classic and contemporary models of attitudes and persuasion. PMID:14717653

Neural correlates of somatoform disorders from a meta-analytic perspective on neuroimaging studies.

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Boeckle, Markus; Schrimpf, Marlene; Liegl, Gregor; Pieh, Christoph

2016-01-01

Somatoform disorders (SD) are common medical disorders with prevalence rates between 3.5% and 18.4%, depending on country and medical setting. SD as outlined in the ICD-10 exhibits various biological, social, and psychological pathogenic factors. Little is known about the neural correlates of SD. The aims of this meta-analysis are to identify neuronal areas that are involved in SD and consistently differ between patients and healthy controls. We conducted a systematic literature research on neuroimaging studies of SD. Ten out of 686 studies fulfilled the inclusion criteria and were analyzed using activation likelihood estimation. Five neuronal areas differ between patients with SD and healthy controls namely the premotor and supplementary motor cortexes, the middle frontal gyrus, the anterior cingulate cortex, the insula, and the posterior cingulate cortex. These areas seem to have a particular importance for the occurrence of SD. Out of the ten studies two did not contribute to any of the clusters. Our results seem to largely overlap with the circuit network model of somatosensory amplification for SD. It is conceivable that functional disorders, independent of the clinical impression, show similar neurobiological processes. While overlaps do occur it is necessary to understand single functional somatic syndromes and their aetiology for future research, terminology, and treatment guidelines.

Neural correlates of somatoform disorders from a meta-analytic perspective on neuroimaging studies

Directory of Open Access Journals (Sweden)

Markus Boeckle

2016-01-01

Full Text Available Somatoform disorders (SD are common medical disorders with prevalence rates between 3.5% and 18.4%, depending on country and medical setting. SD as outlined in the ICD-10 exhibits various biological, social, and psychological pathogenic factors. Little is known about the neural correlates of SD. The aims of this meta-analysis are to identify neuronal areas that are involved in SD and consistently differ between patients and healthy controls. We conducted a systematic literature research on neuroimaging studies of SD. Ten out of 686 studies fulfilled the inclusion criteria and were analyzed using activation likelihood estimation. Five neuronal areas differ between patients with SD and healthy controls namely the premotor and supplementary motor cortexes, the middle frontal gyrus, the anterior cingulate cortex, the insula, and the posterior cingulate cortex. These areas seem to have a particular importance for the occurrence of SD. Out of the ten studies two did not contribute to any of the clusters. Our results seem to largely overlap with the circuit network model of somatosensory amplification for SD. It is conceivable that functional disorders, independent of the clinical impression, show similar neurobiological processes. While overlaps do occur it is necessary to understand single functional somatic syndromes and their aetiology for future research, terminology, and treatment guidelines.

The influence of delaying judgments of learning on metacognitive accuracy: a meta-analytic review.

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Rhodes, Matthew G; Tauber, Sarah K

2011-01-01

Many studies have examined the accuracy of predictions of future memory performance solicited through judgments of learning (JOLs). Among the most robust findings in this literature is that delaying predictions serves to substantially increase the relative accuracy of JOLs compared with soliciting JOLs immediately after study, a finding termed the delayed JOL effect. The meta-analyses reported in the current study examined the predominant theoretical accounts as well as potential moderators of the delayed JOL effect. The first meta-analysis examined the relative accuracy of delayed compared with immediate JOLs across 4,554 participants (112 effect sizes) through gamma correlations between JOLs and memory accuracy. Those data showed that delaying JOLs leads to robust benefits to relative accuracy (g = 0.93). The second meta-analysis examined memory performance for delayed compared with immediate JOLs across 3,807 participants (98 effect sizes). Those data showed that delayed JOLs result in a modest but reliable benefit for memory performance relative to immediate JOLs (g = 0.08). Findings from these meta-analyses are well accommodated by theories suggesting that delayed JOL accuracy reflects access to more diagnostic information from long-term memory rather than being a by-product of a retrieval opportunity. However, these data also suggest that theories proposing that the delayed JOL effect results from a memorial benefit or the match between the cues available for JOLs and those available at test may also provide viable explanatory mechanisms necessary for a comprehensive account.

A meta-analytic review of the effects of exercise on brain-derived neurotrophic factor

OpenAIRE

Szuhany, Kristin L.; Bugatti, Matteo; Otto, Michael W.

2014-01-01

Consistent evidence indicates that exercise improves cognition and mood, with preliminary evidence suggesting that brain-derived neurotrophic factor (BDNF) may mediate these effects. The aim of the current meta-analysis was to provide an estimate of the strength of the association between exercise and increased BDNF levels in humans across multiple exercise paradigms. We conducted a meta-analysis of 29 studies (N = 1,111 participants) examining the effect of exercise on BDNF levels in three e...

The Relation of Empathy and Defending in Bullying: A Meta-Analytic Investigation

Science.gov (United States)

Nickerson, Amanda B.; Aloe, Ariel M.; Werth, Jilynn M.

2015-01-01

This meta-analysis synthesized results about the association between empathy and defending in bullying. A total of 20 studies were included, with 22 effect sizes from 6 studies that separated findings by the defender's gender, and 31 effect sizes from 18 studies that provided effects for the total sample were included in the analysis. The weighted…

Orthodontic bracket bonding without previous adhesive priming: A meta-regression analysis.

Science.gov (United States)

Altmann, Aline Segatto Pires; Degrazia, Felipe Weidenbach; Celeste, Roger Keller; Leitune, Vicente Castelo Branco; Samuel, Susana Maria Werner; Collares, Fabrício Mezzomo

2016-05-01

To determine the consensus among studies that adhesive resin application improves the bond strength of orthodontic brackets and the association of methodological variables on the influence of bond strength outcome. In vitro studies were selected to answer whether adhesive resin application increases the immediate shear bond strength of metal orthodontic brackets bonded with a photo-cured orthodontic adhesive. Studies included were those comparing a group having adhesive resin to a group without adhesive resin with the primary outcome measurement shear bond strength in MPa. A systematic electronic search was performed in PubMed and Scopus databases. Nine studies were included in the analysis. Based on the pooled data and due to a high heterogeneity among studies (I(2)  =  93.3), a meta-regression analysis was conducted. The analysis demonstrated that five experimental conditions explained 86.1% of heterogeneity and four of them had significantly affected in vitro shear bond testing. The shear bond strength of metal brackets was not significantly affected when bonded with adhesive resin, when compared to those without adhesive resin. The adhesive resin application can be set aside during metal bracket bonding to enamel regardless of the type of orthodontic adhesive used.

Bayesian variable selection for post-analytic interrogation of susceptibility loci.

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Chen, Siying; Nunez, Sara; Reilly, Muredach P; Foulkes, Andrea S

2017-06-01

Understanding the complex interplay among protein coding genes and regulatory elements requires rigorous interrogation with analytic tools designed for discerning the relative contributions of overlapping genomic regions. To this aim, we offer a novel application of Bayesian variable selection (BVS) for classifying genomic class level associations using existing large meta-analysis summary level resources. This approach is applied using the expectation maximization variable selection (EMVS) algorithm to typed and imputed SNPs across 502 protein coding genes (PCGs) and 220 long intergenic non-coding RNAs (lncRNAs) that overlap 45 known loci for coronary artery disease (CAD) using publicly available Global Lipids Gentics Consortium (GLGC) (Teslovich et al., 2010; Willer et al., 2013) meta-analysis summary statistics for low-density lipoprotein cholesterol (LDL-C). The analysis reveals 33 PCGs and three lncRNAs across 11 loci with >50% posterior probabilities for inclusion in an additive model of association. The findings are consistent with previous reports, while providing some new insight into the architecture of LDL-cholesterol to be investigated further. As genomic taxonomies continue to evolve, additional classes such as enhancer elements and splicing regions, can easily be layered into the proposed analysis framework. Moreover, application of this approach to alternative publicly available meta-analysis resources, or more generally as a post-analytic strategy to further interrogate regions that are identified through single point analysis, is straightforward. All coding examples are implemented in R version 3.2.1 and provided as supplemental material. © 2016, The International Biometric Society.

The Economic Value of Mangroves: A Meta-Analysis

Science.gov (United States)

Marwa Salem; D. Evan Mercer

2012-01-01

This paper presents a synthesis of the mangrove ecosystem valuation literature through a meta-regression analysis. The main contribution of this study is that it is the first meta-analysis focusing solely on mangrove forests, whereas previous studies have included different types of wetlands. The number of studies included in the regression analysis is 44 for a total...

ADHD and personality: a meta-analytic review

OpenAIRE

Gomez, R.; Corr, P. J.

2014-01-01

We report a meta-analysis of up to 40 data sets that examined the personality dimensions in the Five-Factor Model (FFM) and the integrated Five-Factor Model (IFFM) in relation to ADHD symptom domains of inattention (IA) and hyperactivity/impulsivity (HI). The IFFM incorporated the dimensions of other personality models (in particular, those of Eysenck, Tellegen, and Cloninger, as well as the FFM). Major findings were: (1) IA and HI were both associated with low conscientious inhibition/consci...

Conducting Meta-Analyses Based on p Values

Science.gov (United States)

van Aert, Robbie C. M.; Wicherts, Jelte M.; van Assen, Marcel A. L. M.

2016-01-01

Because of overwhelming evidence of publication bias in psychology, techniques to correct meta-analytic estimates for such bias are greatly needed. The methodology on which the p-uniform and p-curve methods are based has great promise for providing accurate meta-analytic estimates in the presence of publication bias. However, in this article, we show that in some situations, p-curve behaves erratically, whereas p-uniform may yield implausible estimates of negative effect size. Moreover, we show that (and explain why) p-curve and p-uniform result in overestimation of effect size under moderate-to-large heterogeneity and may yield unpredictable bias when researchers employ p-hacking. We offer hands-on recommendations on applying and interpreting results of meta-analyses in general and p-uniform and p-curve in particular. Both methods as well as traditional methods are applied to a meta-analysis on the effect of weight on judgments of importance. We offer guidance for applying p-uniform or p-curve using R and a user-friendly web application for applying p-uniform. PMID:27694466

Genome-wide association study and meta-analysis find that over 40 loci affect risk of type 1 diabetes

DEFF Research Database (Denmark)

Barrett, Jeffrey C; Clayton, David G; Concannon, Patrick

2009-01-01

Type 1 diabetes (T1D) is a common autoimmune disorder that arises from the action of multiple genetic and environmental risk factors. We report the findings of a genome-wide association study of T1D, combined in a meta-analysis with two previously published studies. The total sample set included 7......,514 cases and 9,045 reference samples. Forty-one distinct genomic locations provided evidence for association with T1D in the meta-analysis (P

Allergies and risk of head and neck cancer: an original study plus meta-analysis.

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Hsiao, Jenn-Ren; Ou, Chun-Yen; Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S

2013-01-01

Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. THE CURRENT PAPER REPORTS RESULTS FROM: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27-0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63-0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40-0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54-0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81-1.18). These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.

The neural basis of sex differences in sexual behavior: A quantitative meta-analysis

Science.gov (United States)

Poeppl, Timm B.; Langguth, Berthold; Rupprecht, Rainer; Safron, Adam; Bzdok, Danilo; Laird, Angela R.; Eickhoff, Simon B.

2016-01-01

Sexuality as to its etymology presupposes the duality of sexes. Using quantitative neuroimaging meta-analyses, we demonstrate robust sex differences in the neural processing of sexual stimuli in thalamus, hypothalamus, and basal ganglia. In a narrative review, we show how these relate to the well-established sex differences on the behavioral level. More specifically, we describe the neural bases of known poor agreement between self-reported and genital measures of female sexual arousal, of previously proposed male proneness to affective sexual conditioning, as well as hints of unconscious activation of bonding mechanisms during sexual stimulation in women. In summary, our meta-analytic review demonstrates that neurofunctional sex differences during sexual stimulation can account for well-established sex differences in sexual behavior. PMID:27742561

Meta-analytic comparison of randomized and nonrandomized studies of breast cancer surgery.

Science.gov (United States)

Edwards, Janet P; Kelly, Elizabeth J; Lin, Yongtao; Lenders, Taryn; Ghali, William A; Graham, Andrew J

2012-06-01

Randomized controlled trials (RCTs) are thought to provide the most accurate estimation of "true" treatment effect. The relative quality of effect estimates derived from nonrandomized studies (nRCTs) remains unclear, particularly in surgery, where the obstacles to performing high-quality RCTs are compounded. We performed a meta-analysis of effect estimates of RCTs comparing surgical procedures for breast cancer relative to those of corresponding nRCTs. English-language RCTs of breast cancer treatment in human patients published from 2003 to 2008 were identified in MEDLINE, EMBASE and Cochrane databases. We identified nRCTs using the National Library of Medicine's "related articles" function and reference lists. Two reviewers conducted all steps of study selection. We included studies comparing 2 surgical arms for the treatment of breast cancer. Information on treatment efficacy estimates, expressed as relative risk (RR) for outcomes of interest in both the RCTs and nRCTs was extracted. We identified 12 RCTs representing 10 topic/outcome combinations with comparable nRCTs. On visual inspection, 4 of 10 outcomes showed substantial differences in summary RR. The pooled RR estimates for RCTs versus nRCTs differed more than 2-fold in 2 of 10 outcomes and failed to demonstrate consistency of statistical differences in 3 of 10 cases. A statistically significant difference, as assessed by the z score, was not detected for any of the outcomes. Randomized controlled trials comparing surgical procedures for breast cancer may demonstrate clinically relevant differences in effect estimates in 20%-40% of cases relative to those generated by nRCTs, depending on which metric is used.

Chiral meta-atoms rotated by light

International Nuclear Information System (INIS)

Liu Mingkai; Powell, David A.; Shadrivov, Ilya V.

2012-01-01

We study the opto-mechanical properties of coupled chiral meta-atoms based on a pair of twisted split-ring resonators. By using a simple analytical model in conjunction with the Maxwell stress tensor, we capture insight into the mechanism and find that this structure can be used as a general prototype of subwavelength light-driven actuators over a wide range of frequencies. This coupled structure can provide a strong and tunable torque, and can support different opto-mechanical modes, including uniform rotation, periodically variable rotation and damped oscillations. Our results suggest that chiral meta-atoms are good candidates for creating sub-wavelength motors or wrenches controlled by light.

Chiral meta-atoms rotated by light

Science.gov (United States)

Liu, Mingkai; Powell, David A.; Shadrivov, Ilya V.

2012-07-01

We study the opto-mechanical properties of coupled chiral meta-atoms based on a pair of twisted split-ring resonators. By using a simple analytical model in conjunction with the Maxwell stress tensor, we capture insight into the mechanism and find that this structure can be used as a general prototype of subwavelength light-driven actuators over a wide range of frequencies. This coupled structure can provide a strong and tunable torque, and can support different opto-mechanical modes, including uniform rotation, periodically variable rotation and damped oscillations. Our results suggest that chiral meta-atoms are good candidates for creating sub-wavelength motors or wrenches controlled by light.

Does oral language underpin the development of later behavior problems? A longitudinal meta-analysis.

Science.gov (United States)

Chow, Jason C; Ekholm, Erik; Coleman, Heather

2018-05-24

The purpose of this article is to estimate the overall weighted mean effect of the relation between early language skills and later behavior problems in school-aged children. A systematic literature search yielded 19,790 unduplicated reports, and a structured search strategy and identification procedure yielded 25 unique data sets, with 114 effect sizes for analysis. Eligible reports were then coded, and effect sizes were extracted and synthesized via robust variance estimation and random-effects meta-analytic techniques. The overall correlation between early language and later behavior problems was negative and small (r = -.14, 95% confidence interval [CI] [-.16, -.11]), and controlling for demographic variables did not reduce the magnitude of the inverse relationship between language skill and problem behavior (r = -.16). Moderator analyses identified receptive language, parent-reported behavior measures, gender, and age as significant predictors of the association between language and behavior. This article corroborates the consistent findings of previous meta-analytic and longitudinal studies and further identifies areas, particularly around measurement, for future research. Furthermore, prospective longitudinal evaluations of the relations between language deficits and behavior problems with different types of measures (teacher-/parent-report, direct assessment, classroom observation) is warranted. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Multivariate Methods for Meta-Analysis of Genetic Association Studies.

Science.gov (United States)

Dimou, Niki L; Pantavou, Katerina G; Braliou, Georgia G; Bagos, Pantelis G

2018-01-01

Multivariate meta-analysis of genetic association studies and genome-wide association studies has received a remarkable attention as it improves the precision of the analysis. Here, we review, summarize and present in a unified framework methods for multivariate meta-analysis of genetic association studies and genome-wide association studies. Starting with the statistical methods used for robust analysis and genetic model selection, we present in brief univariate methods for meta-analysis and we then scrutinize multivariate methodologies. Multivariate models of meta-analysis for a single gene-disease association studies, including models for haplotype association studies, multiple linked polymorphisms and multiple outcomes are discussed. The popular Mendelian randomization approach and special cases of meta-analysis addressing issues such as the assumption of the mode of inheritance, deviation from Hardy-Weinberg Equilibrium and gene-environment interactions are also presented. All available methods are enriched with practical applications and methodologies that could be developed in the future are discussed. Links for all available software implementing multivariate meta-analysis methods are also provided.

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.

Born analytical or adopted over time? a study investigating if new analytical tools can ensure the survival of market oriented startups.

OpenAIRE

Skogen, Hege Janson; De la Cruz, Kai

2017-01-01

Masteroppgave(MSc) in Master of Science in Strategic Marketing Management - Handelshøyskolen BI, 2017 This study investigates whether the prevalence of technological advances within quantitative analytics moderates the effect market orientation has on firm performance, and if startups can take advantage of the potential opportunities to ensure their own survival. For this purpose, the authors review previous literature in marketing orientation, startups, marketing analytics, an...

Nonvitamin-K-antagonist oral anticoagulants versus warfarin in patients with atrial fibrillation and previous stroke or transient ischemic attack: An updated systematic review and meta-analysis of randomized controlled trials.

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Ntaios, George; Papavasileiou, Vasileios; Diener, Hans-Chris; Makaritsis, Konstantinos; Michel, Patrik

2017-08-01

Background In a previous systematic review and meta-analysis, we assessed the efficacy and safety of nonvitamin-K antagonist oral anticoagulants versus warfarin in patients with atrial fibrillation and stroke or transient ischemic attack. Since then, new information became available. Aim The aim of the present work was to update the results of the previous systematic review and meta-analysis. Methods We searched PubMed until 24 August 2016 for randomized controlled trials using the following search items: "atrial fibrillation" and "anticoagulation" and "warfarin" and "previous stroke or transient ischemic attack." Eligible studies had to be phase III trials in patients with atrial fibrillation comparing warfarin with nonvitamin-K antagonist oral anticoagulants currently on the market or with the intention to be brought to the market in North America or Europe. The outcomes assessed in the efficacy analysis included stroke or systemic embolism, stroke, ischemic or unknown stroke, disabling or fatal stroke, hemorrhagic stroke, cardiovascular death, death from any cause, and myocardial infarction. The outcomes assessed in the safety analysis included major bleeding, intracranial bleeding, and major gastrointestinal bleeding. We performed fixed effects analyses on intention-to-treat basis. Results Among 183 potentially eligible articles, four were included in the meta-analysis. In 20,500 patients, compared to warfarin, nonvitamin-K antagonist oral anticoagulants were associated with a significant reduction of stroke/systemic embolism (relative risk reduction: 13.7%, absolute risk reduction: 0.78%, number needed to treat to prevent one event: 127), hemorrhagic stroke (relative risk reduction: 50.0%, absolute risk reduction: 0.63%, number needed to treat: 157), any stroke (relative risk reduction: 13.1%, absolute risk reduction: 0.7%, number needed to treat: 142), and intracranial hemorrhage (relative risk reduction: 46.1%, absolute risk reduction: 0.88%, number needed

Vitamin D and Depression: A Systematic Review and Meta-Analysis Comparing Studies with and without Biological Flaws

Directory of Open Access Journals (Sweden)

Simon Spedding

2014-04-01

Full Text Available 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.

Dairy products and colorectal cancer risk : a systematic review and meta-analysis of cohort studies

NARCIS (Netherlands)

Aune, D.; Lau, R.; Chan, D.S.M.; Vieira, R.; Greenwood, D.C.; Kampman, E.; Norat, T.

2012-01-01

Background: Previous studies of the association between intake of dairy products and colorectal cancer risk have indicated an inverse association with milk, however, the evidence for cheese or other dairy products is inconsistent. Methods: We conducted a systematic review and meta-analysis to

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

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.

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

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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…

Pictorial cigarette pack warnings: a meta-analysis of experimental studies.

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Noar, Seth M; Hall, Marissa G; Francis, Diane B; Ribisl, Kurt M; Pepper, Jessica K; Brewer, Noel T

2016-05-01

To inform international research and policy, we conducted a meta-analysis of the experimental literature on pictorial cigarette pack warnings. We systematically searched 7 computerised databases in April 2013 using several search terms. We also searched reference lists of relevant articles. We included studies that used an experimental protocol to test cigarette pack warnings and reported data on both pictorial and text-only conditions. 37 studies with data on 48 independent samples (N=33,613) met criteria. Two independent coders coded all study characteristics. Effect sizes were computed from data extracted from study reports and were combined using random effects meta-analytic procedures. Pictorial warnings were more effective than text-only warnings for 12 of 17 effectiveness outcomes (all pnegative pack attitudes and negative smoking attitudes and (4) more effectively increased intentions to not start smoking and to quit smoking. Participants also perceived pictorial warnings as being more effective than text-only warnings across all 8 perceived effectiveness outcomes. The evidence from this international body of literature supports pictorial cigarette pack warnings as more effective than text-only warnings. Gaps in the literature include a lack of assessment of smoking behaviour and a dearth of theory-based research on how warnings exert their effects. 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/

Hostile attribution of intent and aggressive behavior: A meta-analysis

NARCIS (Netherlands)

Orobio de Castro, B.; Veerman, J.W.; Koops, W.; Bosch, J.D.; Monshouwer, H.J.

2002-01-01

A meta-analytic review was conducted to explain divergent findings on the relation between children's aggressive behavior and hostile attribution of intent to peers. Forty-one studies with 6,017 participants were included in the analysis. Ten studies concerned representative samples from the general

Justice at the millennium, a decade later: a meta-analytic test of social exchange and affect-based perspectives.

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Colquitt, Jason A; Scott, Brent A; Rodell, Jessica B; Long, David M; Zapata, Cindy P; Conlon, Donald E; Wesson, Michael J

2013-03-01

Although a flurry of meta-analyses summarized the justice literature at the turn of the millennium, interest in the topic has surged in the decade since. In particular, the past decade has witnessed the rise of social exchange theory as the dominant lens for examining reactions to justice, and the emergence of affect as a complementary lens for understanding such reactions. The purpose of this meta-analytic review was to test direct, mediating, and moderating hypotheses that were inspired by those 2 perspectives, to gauge their adequacy as theoretical guides for justice research. Drawing on a review of 493 independent samples, our findings revealed a number of insights that were not included in prior meta-analyses. With respect to social exchange theory, our results revealed that the significant relationships between justice and both task performance and citizenship behavior were mediated by indicators of social exchange quality (trust, organizational commitment, perceived organizational support, and leader-member exchange), though such mediation was not apparent for counterproductive behavior. The strength of those relationships did not vary according to whether the focus of the justice matched the target of the performance behavior, contrary to popular assumptions in the literature, or according to whether justice was referenced to a specific event or a more general entity. With respect to affect, our results showed that justice-performance relationships were mediated by positive and negative affect, with the relevant affect dimension varying across justice and performance variables. Our discussion of these findings focuses on the merit in integrating the social exchange and affect lenses in future research.

The neuroanatomy of psychotic diathesis: a meta-analytic review.

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Palaniyappan, Lena; Balain, Vijender; Liddle, Peter F

2012-10-01

Several studies have found widespread structural changes affecting the grey matter at various stages of schizophrenia (the prodrome, first-episode, and the chronic stage). It is unclear which of these neuroanatomical changes are associated with a predisposition or vulnerability to develop schizophrenia rather than the appearance of the clinical features of the illness. 16 voxel-based morphometry (VBM) analyses involving 733 genetically high-risk relatives (HRR) of patients with schizophrenia, 563 healthy controls and 474 patients were meta-analysed using the Signed Differential Mapping (SDM) technique. Two meta-analyses were conducted, with one comparing HRR group with healthy controls and the other comparing HRR group with the patients. A significant grey matter reduction in the lentiform nucleus, amygdala/parahippocampal gyrus and medial prefrontal cortex was seen in association with the genetic diathesis. Grey matter reduction in bilateral insula, inferior frontal gyrus, superior temporal gyrus and the anterior cingulate was seen in association with the disease expression. The neuroanatomical changes associated with the genetic diathesis to develop schizophrenia appear to be different from those that contribute to the clinical expression of the illness. Grey matter abnormalities in multimodal brain regions that have a supervisory function are likely to be central to the expression of the clinical symptoms of schizophrenia. Copyright © 2012 Elsevier Ltd. All rights reserved.

Independent Risk Factors Contributing to Acute Kidney Injury According to Updated Valve Academic Research Consortium-2 Criteria After Transcatheter Aortic Valve Implantation: A Meta-analysis and Meta-regression of 13 Studies.

Science.gov (United States)

Wang, Jiayang; Yu, Wenyuan; Zhou, Ye; Yang, Yong; Li, Chenglong; Liu, Nan; Hou, Xiaotong; Wang, Longfei

2017-06-01

This study aimed to examine the risk factors for transcatheter aortic valve implantation (TAVI)-associated acute kidney injury (AKI) according to the AKI definition from the Valve Academic Research Consortium-2 (VARC-2). A meta-analysis. A total of 661 patients with post-TAVI AKI according to the VARC-2 definition and 2,012 controls were included in the meta-analysis. Patients undergoing TAVI were included in this meta-analysis. Multiple electronic databases were searched using predefined criteria. The diagnosis of AKI was based on the VARC-2 classification. The authors found that preoperative New York Heart Association class IV (odds ratio [OR], 7.77; 95% confidence interval [CI], 3.81-15.85), previous chronic renal disease (CKD) (OR, 2.81; 95% CI, 1.96-4.03), and requirement for transfusion (OR, 2.03; 95% CI, 1.59-2.59) were associated significantly with an increased risk for post-TAVI AKI. Furthermore, previous peripheral vascular disease (PVD), hypertension, atrial fibrillation, congestive heart failure, diabetes mellitus, and stroke were also risk factors for TAVI-associated AKI. Additionally, transfemoral access significantly correlated with a reduced risk for post-TAVI AKI (OR, 0.43; 95% CI, 0.33-0.57). The potential confounders, including Society of Thoracic Surgeons Score, the logistic European System for Cardiac Operative Risk Evaluation, aortic valve area, mean pressure gradient, left ventricular ejection fraction, age, body mass index, contrast volume, and valve type, had no impact on the association between the risk factors and post-TAVI AKI. Subgroup analysis of the eligible studies presenting multivariate logistic regression analysis on the independent risk factors for post-TAVI AKI revealed that previous CKD, previous PVD, and transapical access were independent risk factors for TAVI-associated AKI. The current meta-analysis suggested that previous CKD, previous PVD, and transapical access may be independent risk factors for TAVI-associated AKI

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).

Multi-site study of additive genetic effects on fractional anisotropy of cerebral white matter: Comparing meta and megaanalytical approaches for data pooling.

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Kochunov, Peter; Jahanshad, Neda; Sprooten, Emma; Nichols, Thomas E; Mandl, René C; Almasy, Laura; Booth, Tom; Brouwer, Rachel M; Curran, Joanne E; de Zubicaray, Greig I; Dimitrova, Rali; Duggirala, Ravi; Fox, Peter T; Hong, L Elliot; Landman, Bennett A; Lemaitre, Hervé; Lopez, Lorna M; Martin, Nicholas G; McMahon, Katie L; Mitchell, Braxton D; Olvera, Rene L; Peterson, Charles P; Starr, John M; Sussmann, Jessika E; Toga, Arthur W; Wardlaw, Joanna M; Wright, Margaret J; Wright, Susan N; Bastin, Mark E; McIntosh, Andrew M; Boomsma, Dorret I; Kahn, René S; den Braber, Anouk; de Geus, Eco J C; Deary, Ian J; Hulshoff Pol, Hilleke E; Williamson, Douglas E; Blangero, John; van 't Ent, Dennis; Thompson, Paul M; Glahn, David C

2014-07-15

Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9-85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large "mega-family". We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. Copyright © 2014 Elsevier Inc. All rights reserved.

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

Martial arts participation and externalizing behavior in juveniles : A meta-analytic review

NARCIS (Netherlands)

Gubbels, J.; van der Stouwe, T.; Spruit, A.; Stams, G.J.J.M.

2016-01-01

Martial arts are very popular among juveniles all over the world, but the relation between martial arts and externalizing behavior in juveniles remains unclear. The current multilevel meta-analysis of 12 studies, including 94 effect sizes and N = 5949 juveniles, was conducted to examine the relation

Evaluation methodology for comparing memory and communication of analytic processes in visual analytics

Energy Technology Data Exchange (ETDEWEB)

Ragan, Eric D [ORNL; Goodall, John R [ORNL

2014-01-01

Provenance tools can help capture and represent the history of analytic processes. In addition to supporting analytic performance, provenance tools can be used to support memory of the process and communication of the steps to others. Objective evaluation methods are needed to evaluate how well provenance tools support analyst s memory and communication of analytic processes. In this paper, we present several methods for the evaluation of process memory, and we discuss the advantages and limitations of each. We discuss methods for determining a baseline process for comparison, and we describe various methods that can be used to elicit process recall, step ordering, and time estimations. Additionally, we discuss methods for conducting quantitative and qualitative analyses of process memory. By organizing possible memory evaluation methods and providing a meta-analysis of the potential benefits and drawbacks of different approaches, this paper can inform study design and encourage objective evaluation of process memory and communication.

Child Development in the Face of Rural-to-Urban Migration in China: A Meta-Analytic Review.

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Wang, Lamei; Mesman, Judi

2015-11-01

In the last 30 years, China has undergone one of the largest rural-to-urban migrations in human history, with many children left behind because of parental migration. We present a meta-analytic review of empirical studies on Chinese children's rural-to-urban migration and on rural children left behind because of parental migration. We examine how these events relate to children's emotional, social, and academic developmental outcomes. We include publications in English and in Chinese to uncover and quantify a part of the research literature that has been inaccessible to most Western scholars in the field of child and family studies. Overall, both migrant children and children left behind by migrant parents in China show significantly less favorable functioning across domains than other Chinese children. It appears that, similar to processes found in other parts of the world, the experience of economic and acculturation stress as well as disrupted parent-child relations constitute a risk for nonoptimal child functioning in the Chinese context. Further, we found evidence for publication bias against studies showing less favorable development for migrant children and children left behind. We discuss the results in terms of challenges to Chinese society and to future empirical research on Chinese family life. © The Author(s) 2015.

Change Driven by Nature: A Meta-Analytic Review of the Proactive Personality Literature

Science.gov (United States)

Fuller, Bryan, Jr.; Marler, Laura E.

2009-01-01

This study provides the first comprehensive review of literature examining proactive personality. The authors use career success as a broad organizing framework, meta-analyzing 313 correlations from 107 studies. Results indicate proactive personality is positively related to objective and subjective career success. Further, results indicate…

The Happy Culture: A Theoretical, Meta-Analytic, and Empirical Review of the Relationship Between Culture and Wealth and Subjective Well-Being

Science.gov (United States)

Steel, Piers; Taras, Vasyl; Uggerslev, Krista; Bosco, Frank

2017-01-01

Do cultural values enhance financial and subjective well-being (SWB)? Taking a multidisciplinary approach, we meta-analytically reviewed the field, found it thinly covered, and focused on individualism. In counter, we collected a broad array of individual-level data, specifically an Internet sample of 8,438 adult respondents. Individual SWB was most strongly associated with cultural values that foster relationships and social capital, which typically accounted for more unique variance in life satisfaction than an individual’s salary. At a national level, we used mean-based meta-analysis to construct a comprehensive cultural and SWB database. Results show some reversals from the individual level, particularly masculinity’s facet of achievement orientation. In all, the happy nation has low power distance and low uncertainty avoidance, but is high in femininity and individualism, and these effects are interrelated but still partially independent from political and economic institutions. In short, culture matters for individual and national well-being. PMID:28770649

The Happy Culture: A Theoretical, Meta-Analytic, and Empirical Review of the Relationship Between Culture and Wealth and Subjective Well-Being.

Science.gov (United States)

Steel, Piers; Taras, Vasyl; Uggerslev, Krista; Bosco, Frank

2018-05-01

Do cultural values enhance financial and subjective well-being (SWB)? Taking a multidisciplinary approach, we meta-analytically reviewed the field, found it thinly covered, and focused on individualism. In counter, we collected a broad array of individual-level data, specifically an Internet sample of 8,438 adult respondents. Individual SWB was most strongly associated with cultural values that foster relationships and social capital, which typically accounted for more unique variance in life satisfaction than an individual's salary. At a national level, we used mean-based meta-analysis to construct a comprehensive cultural and SWB database. Results show some reversals from the individual level, particularly masculinity's facet of achievement orientation. In all, the happy nation has low power distance and low uncertainty avoidance, but is high in femininity and individualism, and these effects are interrelated but still partially independent from political and economic institutions. In short, culture matters for individual and national well-being.

EMDR therapy for PTSD after motor vehicle accidents: meta-analytic evidence for specific treatment

Directory of Open Access Journals (Sweden)

Maddalena eBoccia

2015-04-01

Full Text Available Motor vehicle accident (MVA victims may suffer both acute and post-traumatic stress disorders (PTSD. With PTSD affecting social, interpersonal and occupational functioning, clinicians as well as the National Institute of Health are very interested in identifying the most effective psychological treatment to reduce PTSD. From research findings, eye movement desensitization and reprocessing (EMDR therapy is considered as one of the effective treatment of PTSD. In this paper, we present the results of a meta-analysis of fMRI studies on PTSD after MVA through activation likelihood estimation. We found that PTSD following MVA is characterized by neural modifications in the anterior cingulate cortex (ACC, a cerebral structure involved in fear-conditioning mechanisms. Basing on previous findings in both humans and animals, which demonstrate that desensitization techniques and extinction protocols act on the limbic system, the effectiveness of EMDR and of cognitive behavioral therapies (CBT may be related to the fact that during these therapies the ACC is stimulated by desensitization.

EMDR therapy for PTSD after motor vehicle accidents: meta-analytic evidence for specific treatment

Science.gov (United States)

Boccia, Maddalena; Piccardi, Laura; Cordellieri, Pierluigi; Guariglia, Cecilia; Giannini, Anna Maria

2015-01-01

Motor vehicle accident (MVA) victims may suffer both acute and post-traumatic stress disorders (PTSD). With PTSD affecting social, interpersonal and occupational functioning, clinicians as well as the National Institute of Health are very interested in identifying the most effective psychological treatment to reduce PTSD. From research findings, eye movement desensitization and reprocessing (EMDR) therapy is considered as one of the effective treatment of PTSD. In this paper, we present the results of a meta-analysis of fMRI studies on PTSD after MVA through activation likelihood estimation. We found that PTSD following MVA is characterized by neural modifications in the anterior cingulate cortex (ACC), a cerebral structure involved in fear-conditioning mechanisms. Basing on previous findings in both humans and animals, which demonstrate that desensitization techniques and extinction protocols act on the limbic system, the effectiveness of EMDR and of cognitive behavioral therapies (CBT) may be related to the fact that during these therapies the ACC is stimulated by desensitization. PMID:25954183

Education and Entrepreneurship in Industrialized Countries: A Meta-analysis

NARCIS (Netherlands)

vander Sluis, J.; van Praag, C.M.; Vijverberg, W.

2004-01-01

This paper provides a meta-analytical review of empirical studies into the impact of schooling on entrepreneurship selection and performance. We first describe the main effects found in the current entrepreneurship literature. We then explain the variance in results across the hundreds of empirical

Psychometric Properties of “Community Assessment of Psychic Experiences”: Review and Meta-analyses

Science.gov (United States)

Mark, Winifred; Toulopoulou, Timothea

2016-01-01

The Community Assessment of Psychic Experiences (CAPE) has been used extensively as a measurement for psychosis proneness in clinical and research settings. However, no prior review and meta-analysis have comprehensively examined psychometric properties (reliability and validity) of CAPE scores across different studies. To study CAPE’s internal reliability—ie, how well scale items correlate with one another—111 studies were reviewed. Of these, 18 reported unique internal reliability coefficients using data at hand, which were aggregated in a meta-analysis. Furthermore, to confirm the number and nature of factors tapped by CAPE, 17 factor analytic studies were reviewed and subjected to meta-analysis in cases of discrepancy. Results suggested that CAPE scores were psychometrically reliable—ie, scores obtained could be attributed to true score variance. Our review of factor analytic studies supported a 3-factor model for CAPE consisting of “Positive”, “Negative”, and “Depressive” subscales; and a tripartite structure for the Negative dimension consisting of “Social withdrawal”, “Affective flattening”, and “Avolition” subdimensions. Meta-analysis of factor analytic studies of the Positive dimension revealed a tridimensional structure consisting of “Bizarre experiences”, “Delusional ideations”, and “Perceptual anomalies”. Information on reliability and validity of CAPE scores is important for ensuring accurate measurement of the psychosis proneness phenotype, which in turn facilitates early detection and intervention for psychotic disorders. Apart from enhancing the understanding of psychometric properties of CAPE scores, our review revealed questionable reporting practices possibly reflecting insufficient understanding regarding the significance of psychometric properties. We recommend increased focus on psychometrics in psychology programmes and clinical journals. PMID:26150674

Linking job demands and resources to employee engagement and burnout: a theoretical extension and meta-analytic test.

Science.gov (United States)

Crawford, Eean R; Lepine, Jeffery A; Rich, Bruce Louis

2010-09-01

We refine and extend the job demands-resources model with theory regarding appraisal of stressors to account for inconsistencies in relationships between demands and engagement, and we test the revised theory using meta-analytic structural modeling. Results indicate support for the refined and updated theory. First, demands and burnout were positively associated, whereas resources and burnout were negatively associated. Second, whereas relationships among resources and engagement were consistently positive, relationships among demands and engagement were highly dependent on the nature of the demand. Demands that employees tend to appraise as hindrances were negatively associated with engagement, and demands that employees tend to appraise as challenges were positively associated with engagement. Implications for future research are discussed. Copyright 2010 APA, all rights reserved

How to conduct a qualitative meta-analysis: Tailoring methods to enhance methodological integrity.

Science.gov (United States)

Levitt, Heidi M

2018-05-01

Although qualitative research has long been of interest in the field of psychology, meta-analyses of qualitative literatures (sometimes called meta-syntheses) are still quite rare. Like quantitative meta-analyses, these methods function to aggregate findings and identify patterns across primary studies, but their aims, procedures, and methodological considerations may vary. This paper explains the function of qualitative meta-analyses and their methodological development. Recommendations have broad relevance but are framed with an eye toward their use in psychotherapy research. Rather than arguing for the adoption of any single meta-method, this paper advocates for considering how procedures can best be selected and adapted to enhance a meta-study's methodological integrity. Through the paper, recommendations are provided to help researchers identify procedures that can best serve their studies' specific goals. Meta-analysts are encouraged to consider the methodological integrity of their studies in relation to central research processes, including identifying a set of primary research studies, transforming primary findings into initial units of data for a meta-analysis, developing categories or themes, and communicating findings. The paper provides guidance for researchers who desire to tailor meta-analytic methods to meet their particular goals while enhancing the rigor of their research.

All-dielectric meta-holograms with holographic images transforming longitudinally

KAUST Repository

Wang, Qiu; Xu, Quan; Zhang, Xueqian; Tian, Chunxiu; Xu, Yuehong; Gu, Jianqiang; Tian, Zhen; Ouyang, Chunmei; Zhang, Xixiang; Han, Jiaguang; Zhang, Weili

2017-01-01

Metasurfaces are unique subwavelength geometries capable of engineering electromagnetic waves at will, delivering new opportunities for holography. Most previous meta-holograms, so-called phase-only meta-holograms, modulate only the amplitude distribution of a virtual object, and require optimizing techniques to improve the image quality. However, the phase distribution of the reconstructed image is usually overlooked in previous studies, leading to inevitable information loss. Here, we demonstrate all-dielectric meta-holograms that allow tailoring of both the phase and amplitude distributions of virtual objects. Several longitudinal manipulations of the holographic images are theoretically and experimentally demonstrated, including shifting, stretching, and rotating, enabling a large depth of focus. Furthermore, a new meta-hologram with a three-dimensional holographic design method is demonstrated with an even enhanced depth of focus. The proposed meta-holograms offer more freedom in holographic design and open new avenues for designing complex three-dimensional holography.

All-dielectric meta-holograms with holographic images transforming longitudinally

KAUST Repository

Wang, Qiu

2017-11-22

Metasurfaces are unique subwavelength geometries capable of engineering electromagnetic waves at will, delivering new opportunities for holography. Most previous meta-holograms, so-called phase-only meta-holograms, modulate only the amplitude distribution of a virtual object, and require optimizing techniques to improve the image quality. However, the phase distribution of the reconstructed image is usually overlooked in previous studies, leading to inevitable information loss. Here, we demonstrate all-dielectric meta-holograms that allow tailoring of both the phase and amplitude distributions of virtual objects. Several longitudinal manipulations of the holographic images are theoretically and experimentally demonstrated, including shifting, stretching, and rotating, enabling a large depth of focus. Furthermore, a new meta-hologram with a three-dimensional holographic design method is demonstrated with an even enhanced depth of focus. The proposed meta-holograms offer more freedom in holographic design and open new avenues for designing complex three-dimensional holography.

Lack of association of poultry and eggs intake with risk of non-Hodgkin lymphoma: a meta-analysis of observational studies.

Science.gov (United States)

Dong, Y; Wu, G

2017-09-01

We carried out a meta-analysis to explore the association between poultry and eggs consumption and non-Hodgkin lymphoma (NHL) risk according to the published observational studies. A search of databases was performed in MEDLINE and EMBASE from their inception to March 2015. We derived meta-analytic estimates using random-effects models, and assessed between-study heterogeneity using the Cochran's Q and I 2 statistics. We identified a total of nine case-control and three prospective cohort studies, including 11,271 subjects with NHL. The summary relative risks for high vs. low analyses were 1.04 (95% confidence intervals [CIs]: 0.86-1.27; p heterogeneity poultry consumption and 1.15 (95% CIs: 0.87-1.51; p heterogeneity poultry consumption, whereas no significant factors were responsible for the high heterogeneity among the studies on eggs consumption. Limited data suggested a null association between consumption of poultry and eggs and NHL subtypes. Findings from our meta-analysis indicate that consumption of poultry and eggs may be not related to NHL risk. © 2016 John Wiley & Sons Ltd.

Estudio Meta-Analítico de Características Diferenciales Entre Maltratadores y no Maltratadores: El Caso de la Psicopatología y el Consumo de Alcohol o Drogas Meta-Analytic Study of Differential Characteristics Between Batterers and Non-Batterers: The Case of Psychopathology and Consumption of Alcohol and Drugs

Directory of Open Access Journals (Sweden)

Victoria Ferrer

2004-05-01

Full Text Available Últimamente la violencia doméstica ha pasado a ser considerada como un verdadero problema social. Entre las cuestiones que han generado mayor interés está la caracterización de los agresores, es decir, tratar de delimitar las características que diferencian a maltratadores de no maltratadores. Este interés ha dado lugar a gran cantidad de literatura cuyas conclusiones parecen provisionales y en ocasiones confusas. El objetivo de este trabajo es realizar una revisión meta-analítica de la literatura que compara a maltratadores y no maltratadores en cuanto a psicopatología y consumo de alcohol y drogas. Los resultados obtenidos indican que, en general, hay diferencias significativas aunque limitadas en cuanto a su magnitud entre unos y otros en cuanto a estas variables. Se discuten las implicaciones y limitaciones de estos resultados.Domestic violence has been regarded as an important social problem during the last years. One of the questions that have generated more interest is the perpetrator profile, that is the features that differentiate male batterers from male non-batterers. A raising amount of literature exists on this matter, although conclusions seem yet to be provisional. This piece of research offers a meta-analytic review about the literature that compares male batterers and non-batterers in psychopathology and use of alcohol and drugs. These meta-analytic findings offer support for the existence of limited differences between male batterers and non-batterers in these variables. The implications and limitations of these results are discussed.

ABO blood group and esophageal carcinoma risk: from a case-control study in Chinese population to meta-analysis.

Science.gov (United States)

Wang, Wei; Liu, Lei; Wang, Zhiwei; Lu, Xiaopeng; Wei, Min; Lin, Tianlong; Zhang, Yixin; Jiang, Songqi; Wang, Qiang; Cao, Ziang; Shi, Minxin

2014-10-01

The association between ABO blood group and the risk of esophageal carcinoma (EC) in previously published studies is uncertain and conflicting. The aim of the current study was to determine the correlation of ABO blood group with EC risk via a case-control study and meta-analysis. We performed a population-based case-control study of 3,595 cases and 41,788 controls in Chinese population to evaluate the association between ABO blood group and EC risk. Then, a comprehensive meta-analysis combining our original data and previously published data was conducted to clearly discern the real relationship. The strength of association was measured by odds ratios (ORs) with 95% confidence intervals (CI). In our case-control study, the risk of EC in blood group B was significantly higher than that in non-B groups (A, O, and AB) (OR = 1.15, 95% CI 1.09-1.21). Compared with non-O groups (A, B, and AB), individuals with blood group O demonstrated a reduced risk of EC (OR = 0.90, 95% CI 0.85-0.94). The meta-analysis also indicated that blood group B was associated with significantly higher EC risk (OR = 1.20, 95% CI 1.10-1.31), and people with blood group O had a decreased EC risk (OR = 0.94, 95% CI 0.90-0.99). Neither the case-control study nor the meta-analysis produced any significant association of blood group A or AB with EC risk. Results from our case-control study and the followed meta-analysis confirmed that there was an increased risk of EC in blood group B individuals, whereas a decreased risk of EC was observed in blood group O individuals.

The Association Between Anxiety and Falls: A Meta-Analysis.

Science.gov (United States)

Hallford, David John; Nicholson, Geoff; Sanders, Kerrie; McCabe, Marita P

2017-09-01

Falls occur frequently among older adults and can lead to a range of adverse and debilitating outcomes. Although symptoms of clinical anxiety have been implicated as risk factors for falls, there is no current consensus on the empirical association between anxiety and falls. The current study aimed to address this gap in the literature by conducting a quantitative, meta-analytic review of findings from previous studies. A systematic literature search of bibliographic databases was conducted, yielding 18 studies that fit the criteria for inclusion in the meta-analysis. A random-effects model of all 18 studies showed a significant overall odds ratio of 1.53 (95% CI 1.28-1.83, p anxiety were associated with a 53% increased likelihood of falls. A high amount of variance among effect sizes was observed. Only age was identified as a moderator of this relationship in a subgroup of the samples. Clinical anxiety is associated with falls, however, further research is required to elucidate the factors that might moderate or mediate this relationship, the casual pathways through which they are related, and the associations between different types of anxiety and falls. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Forecasting urban water demand: A meta-regression analysis.

Science.gov (United States)

Sebri, Maamar

2016-12-01

Water managers and planners require accurate water demand forecasts over the short-, medium- and long-term for many purposes. These range from assessing water supply needs over spatial and temporal patterns to optimizing future investments and planning future allocations across competing sectors. This study surveys the empirical literature on the urban water demand forecasting using the meta-analytical approach. Specifically, using more than 600 estimates, a meta-regression analysis is conducted to identify explanations of cross-studies variation in accuracy of urban water demand forecasting. Our study finds that accuracy depends significantly on study characteristics, including demand periodicity, modeling method, forecasting horizon, model specification and sample size. The meta-regression results remain robust to different estimators employed as well as to a series of sensitivity checks performed. The importance of these findings lies in the conclusions and implications drawn out for regulators and policymakers and for academics alike. Copyright © 2016. Published by Elsevier Ltd.

Planning performance in schizophrenia patients: a meta-analysis of the influence of task difficulty and clinical and sociodemographic variables.

Science.gov (United States)

Knapp, F; Viechtbauer, W; Leonhart, R; Nitschke, K; Kaller, C P

2017-08-01

Despite a large body of research on planning performance in adult schizophrenia patients, results of individual studies are equivocal, suggesting either no, moderate or severe planning deficits. This meta-analysis therefore aimed to quantify planning deficits in schizophrenia and to examine potential sources of the heterogeneity seen in the literature. The meta-analysis comprised outcomes of planning accuracy of 1377 schizophrenia patients and 1477 healthy controls from 31 different studies which assessed planning performance using tower tasks such as the Tower of London, the Tower of Hanoi and the Stockings of Cambridge. A meta-regression analysis was applied to assess the influence of potential moderator variables (i.e. sociodemographic and clinical variables as well as task difficulty). The findings indeed demonstrated a planning deficit in schizophrenia patients (mean effect size: ; 95% confidence interval 0.56-0.78) that was moderated by task difficulty in terms of the minimum number of moves required for a solution. The results did not reveal any significant relationship between the extent of planning deficits and sociodemographic or clinical variables. The current results provide first meta-analytic evidence for the commonly assumed impairments of planning performance in schizophrenia. Deficits are more likely to become manifest in problem items with higher demands on planning ahead, which may at least partly explain the heterogeneity of previous findings. As only a small fraction of studies reported coherent information on sample characteristics, future meta-analyses would benefit from more systematic reports on those variables.

Understanding organizational commitment: A meta-analytic examination of the roles of the five-factor model of personality and culture.

Science.gov (United States)

Choi, Daejeong; Oh, In-Sue; Colbert, Amy E

2015-09-01

We examined the relationships between the Five-Factor Model (FFM) of personality traits and three forms of organizational commitment (affective, normative, and continuance commitment) and their variability across individualistic and collectivistic cultures. Meta-analytic results based on 55 independent samples from 50 studies (N = 18,262) revealed that (a) all FFM traits had positive relationships with affective commitment; (b) all FFM traits had positive relationships with normative commitment; and (c) Emotional Stability, Extraversion, and Openness to Experience had negative relationships with continuance commitment. In particular, Agreeableness was found to be the trait most strongly related to both affective and normative commitment. The results also showed that Agreeableness had stronger relationships with affective and normative commitment in collectivistic cultures than in individualistic cultures. We provide theoretical and practical implications of these findings for personality, job attitudes, and employee selection and retention. (c) 2015 APA, all rights reserved).

Meta-analysis of the effectiveness of psychological and medical treatments for binge-eating disorder (MetaBED): study protocol.

Science.gov (United States)

Hilbert, Anja; Petroff, David; Herpertz, Stephan; Kersting, Anette; Pietrowsky, Reinhard; Tuschen-Caffier, Brunna; Vocks, Silja; Schmidt, Ricarda

2017-03-29

Binge-eating disorder (BED) was included as its own diagnostic entity in the Fifth Edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). An increasing number of treatment studies have been published, but an up-to-date comprehensive meta-analysis on diverse treatment approaches for BED is lacking. In an updated and extension of a previous meta-analysis, the goals of this study are to assess the short-term and long-term effectiveness of psychological and medical treatments for BED. We will search bibliographic databases and study registries, including manual searches for studies published before January 2016. The search strategy will include terms relating to binge eating and diverse forms of psychological and medical interventions. Language will be restricted to English. The studies included will be treatment studies, that is, randomised-controlled trials, and non-randomised and non-controlled studies, for individuals with BED (DSM-IV or DSM-5), and studies that provided a pre-treatment and at least one post-treatment or follow-up assessment of binge eating. The primary outcomes will be the number of binge-eating episodes, abstinence from binge eating and diagnosis of BED at post-treatment and/or follow-up(s), and changes from pre-treatment to post-treatment and/or follow-up(s). Likewise, as secondary outcomes, eating disorder and general psychopathology, quality of life, and body weight will be analysed and adverse events and treatment drop-out will be examined. Study search, selection and data extraction, including risk of bias assessment, will be independently performed by 2 reviewers and consensus will be sought. Moderator analyses will be conducted, and equity aspects will be considered. Sensitivity analyses will be conducted to determine the robustness of the results. Ethical approval is not required for this meta-analysis. Published in a peer-reviewed journal and disseminated electronically and in print, this meta-analysis will form

A meta-analysis of the price elasticity of gasoline demand. A SUR approach

Energy Technology Data Exchange (ETDEWEB)

Brons, Martijn; Rietveld, Piet [Department of Spatial Economics, Vrije Universiteit, De Boelelaan 1105, 1081 HV Amsterdam (Netherlands); Tinbergen Institute Amsterdam (TIA), Roetersstraat 31, 1018 WB Amsterdam (Netherlands); Nijkamp, Peter [Department of Spatial Economics, Vrije Universiteit, De Boelelaan 1105, 1081 HV Amsterdam (Netherlands); Tinbergen Institute Amsterdam (TIA), Roetersstraat 31, 1018 WB Amsterdam (Netherlands); The Netherlands Organisation of Scientific Research (NWO), postbus 93138 - 2509 AC Den Haag (Netherlands); Pels, Eric [Department of Spatial Economics, Vrije Universiteit, De Boelelaan 1105, 1081 HV Amsterdam (Netherlands)

2008-09-15

Automobile gasoline demand can be expressed as a multiplicative function of fuel efficiency, mileage per car and car ownership. This implies a linear relationship between the price elasticity of total fuel demand and the price elasticities of fuel efficiency, mileage per car and car ownership. In this meta-analytical study we aim to investigate and explain the variation in empirical estimates of the price elasticity of gasoline demand. A methodological novelty is that we use the linear relationship between the elasticities to develop a meta-analytical estimation approach based on a Seemingly Unrelated Regression (SUR) model with Cross Equation Restrictions. This approach enables us to combine observations of different elasticities and thus increase our sample size. Furthermore, it allows for a more detailed interpretation of our meta-regression results. The empirical results of the study demonstrate that the SUR approach leads to more precise results (i.e., lower standard errors) than a standard meta-analytical approach. We find that, with mean short run and long run price elasticities of - 0.34 and - 0.84, respectively, the demand for gasoline is not very price sensitive. Both in the short and the long run, the impact of a change in the gasoline price on demand is mainly driven by responses in fuel efficiency and mileage per car and to a slightly lesser degree by changes in car ownership. Furthermore, we find that study characteristics relating to the geographic area studied, the year of the study, the type of data used, the time horizon and the functional specification of the demand equation have a significant impact on the estimated value of the price elasticity of gasoline demand. (author)

A meta-analysis of the price elasticity of gasoline demand. A SUR approach

International Nuclear Information System (INIS)

Brons, Martijn; Rietveld, Piet; Nijkamp, Peter; Pels, Eric

2008-01-01

Automobile gasoline demand can be expressed as a multiplicative function of fuel efficiency, mileage per car and car ownership. This implies a linear relationship between the price elasticity of total fuel demand and the price elasticities of fuel efficiency, mileage per car and car ownership. In this meta-analytical study we aim to investigate and explain the variation in empirical estimates of the price elasticity of gasoline demand. A methodological novelty is that we use the linear relationship between the elasticities to develop a meta-analytical estimation approach based on a Seemingly Unrelated Regression (SUR) model with Cross Equation Restrictions. This approach enables us to combine observations of different elasticities and thus increase our sample size. Furthermore, it allows for a more detailed interpretation of our meta-regression results. The empirical results of the study demonstrate that the SUR approach leads to more precise results (i.e., lower standard errors) than a standard meta-analytical approach. We find that, with mean short run and long run price elasticities of - 0.34 and - 0.84, respectively, the demand for gasoline is not very price sensitive. Both in the short and the long run, the impact of a change in the gasoline price on demand is mainly driven by responses in fuel efficiency and mileage per car and to a slightly lesser degree by changes in car ownership. Furthermore, we find that study characteristics relating to the geographic area studied, the year of the study, the type of data used, the time horizon and the functional specification of the demand equation have a significant impact on the estimated value of the price elasticity of gasoline demand. (author)

Sex Differences in Objective and Projective Dependency Tests: A Meta-Analytic Review.

Science.gov (United States)

Bornstein, Robert F.

1995-01-01

A meta-analysis of 97 studies published since 1950 that assessed sex differences in scores on objective and projective dependency tests indicated that women consistently obtained higher dependency scores on objective tests, and men obtained higher scores on projective tests. Findings are discussed in terms of sex role socialization. (SLD)

Investigation of publication bias in meta-analyses of diagnostic test accuracy: a meta-epidemiological study

NARCIS (Netherlands)

van Enst, W. Annefloor; Ochodo, Eleanor; Scholten, Rob J. P. M.; Hooft, Lotty; Leeflang, Mariska M.

2014-01-01

The validity of a meta-analysis can be understood better in light of the possible impact of publication bias. The majority of the methods to investigate publication bias in terms of small study-effects are developed for meta-analyses of intervention studies, leaving authors of diagnostic test

Meta-analytic evaluation of the association between head injury and risk of amyotrophic lateral sclerosis.

Science.gov (United States)

Watanabe, Yukari; Watanabe, Takamitsu

2017-10-01

Head injury is considered as a potential risk factor for amyotrophic lateral sclerosis (ALS). However, several recent studies have suggested that head injury is not a cause, but a consequence of latent ALS. We aimed to evaluate such a possibility of reverse causation with meta-analyses considering time lags between the incidence of head injuries and the occurrence of ALS. We searched Medline and Web of Science for case-control, cross-sectional, or cohort studies that quantitatively investigated the head-injury-related risk of ALS and were published until 1 December 2016. After selecting appropriate publications based on PRISMA statement, we performed random-effects meta-analyses to calculate odds ratios (ORs) and 95% confidence intervals (CI). Sixteen of 825 studies fulfilled the eligibility criteria. The association between head injuries and ALS was statistically significant when the meta-analysis included all the 16 studies (OR 1.45, 95% CI 1.21-1.74). However, in the meta-analyses considering the time lags between the experience of head injuries and diagnosis of ALS, the association was weaker (OR 1.21, 95% CI 1.01-1.46, time lag ≥ 1 year) or not significant (e.g. OR 1.16, 95% CI 0.84-1.59, time lag ≥ 3 years). Although it did not deny associations between head injuries and ALS, the current study suggests a possibility that such a head-injury-oriented risk of ALS has been somewhat overestimated. For more accurate evaluation, it would be necessary to conduct more epidemiological studies that consider the time lags between the occurrence of head injuries and the diagnosis of ALS.

The Interpersonal Adaptiveness of Dispositional Guilt and Shame: A Meta-Analytic Investigation.

Science.gov (United States)

Tignor, Stefanie M; Colvin, C Randall

2017-06-01

Despite decades of empirical research, conclusions regarding the adaptiveness of dispositional guilt and shame are mixed. We use meta-analysis to summarize the empirical literature and clarify these ambiguities. Specifically, we evaluate how guilt and shame are uniquely related to pro-social orientation and, in doing so, highlight the substantial yet under-acknowledged impact of researchers' methodological choices. A series of meta-analyses was conducted investigating the relationship between dispositional guilt (or shame) and pro-social orientation. Two main methodological moderators of interest were tested: test format (scenario vs. checklist) and statistical analysis (semi-partial vs. zero-order correlations). Among studies employing zero-order correlations, dispositional guilt was positively correlated with pro-social orientation (k = 63, Mr = .13, p guilt studies only, with scenario measures producing significantly stronger effects. Semi-partial correlations resulted in significantly stronger effects among guilt and shame studies. Although dispositional guilt and shame are differentially related to pro-social orientation, such relationships depend largely on the methodological choices of the researcher, particularly in the case of guilt. Implications for the study of these traits are discussed. © 2016 Wiley Periodicals, Inc.

Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry

Science.gov (United States)

Segerstrom, Suzanne C.; Miller, Gregory E.

2004-01-01

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of…

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,…

A meta-analytic review of measurement equivalence study findings of the SF-36® and SF-12® Health Surveys across electronic modes compared to paper administration.

Science.gov (United States)

White, Michelle K; Maher, Stephen M; Rizio, Avery A; Bjorner, Jakob B

2018-04-16

Patient-reported outcome (PRO) measures originally developed for paper administration are increasingly being administered electronically in clinical trials and other health research studies. Three published meta-analyses of measurement equivalence among paper and electronic modes aggregated findings across hundreds of PROs, but there has not been a similar meta-analysis that addresses a single PRO, partly because there are not enough published measurement equivalence studies using the same PRO. Because the SF-36 (R) Health Survey (SF-36) is a widely used PRO, the aim of this study was to conduct a meta-analysis of measurement equivalence studies of this survey. A literature search of several medical databases used search terms for variations of "SF-36" or "SF-12" and "equivalence" in the title or abstract of English language publications. The eight scale scores and two summary measures of the SF-36 and SF-12 were transformed to norm-based scores (NBS) using developer guidelines. A threshold of within ± 2 NBS points was set as the margin of equivalence. Comprehensive meta-analysis software was used. Twenty-five studies were included in the meta-analysis. Results indicated that mean differences across domains and summary scores ranged from 0.01 to 0.39 while estimates of agreement ranged from 0.76 to 0.91, all well within the equivalence threshold. Moderator analyses showed that time between administration, survey language, and type of electronic device did not influence equivalence. The results of the meta-analysis support equivalence of paper-based and electronic versions of the SF-36 and SF-12 across a variety of disease populations, countries, and electronic modes.

Meta-analysis as Statistical and Analytical Method of Journal’s Content Scientific Evaluation

Science.gov (United States)

Masic, Izet; Begic, Edin

2015-01-01

Introduction: A meta-analysis is a statistical and analytical method which combines and synthesizes different independent studies and integrates their results into one common result. Goal: Analysis of the journals “Medical Archives”, “Materia Socio Medica” and “Acta Informatica Medica”, which are located in the most eminent indexed databases of the biomedical milieu. Material and methods: The study has retrospective and descriptive character, and included the period of the calendar year 2014. Study included six editions of all three journals (total of 18 journals). Results: In this period was published a total of 291 articles (in the “Medical Archives” 110, “Materia Socio Medica” 97, and in “Acta Informatica Medica” 84). The largest number of articles was original articles. Small numbers have been published as professional, review articles and case reports. Clinical events were most common in the first two journals, while in the journal “Acta Informatica Medica” belonged to the field of medical informatics, as part of pre-clinical medical disciplines. Articles are usually required period of fifty to fifty nine days for review. Articles were received from four continents, mostly from Europe. The authors are most often from the territory of Bosnia and Herzegovina, then Iran, Kosovo and Macedonia. Conclusion: The number of articles published each year is increasing, with greater participation of authors from different continents and abroad. Clinical medical disciplines are the most common, with the broader spectrum of topics and with a growing number of original articles. Greater support of the wider scientific community is needed for further development of all three of the aforementioned journals. PMID:25870484

Selecting Suicide Ideation Assessment Instruments: A Meta-Analytic Review

Science.gov (United States)

Erford, Bradley T.; Jackson, Jessica; Bardhoshi, Gerta; Duncan, Kelly; Atalay, Zumra

2018-01-01

Psychometric meta-analyses and reviews were provided for four commonly used suicidal ideation instruments: the Beck Scale for Suicide Ideation, the Suicide Ideation Questionnaire, the Suicide Probability Scale, and Columbia--Suicide Severity Rating Scale. Practical and technical issues and best use recommendations for screening and outcome…

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.

Integrating motivational, social, and contextual work design features: a meta-analytic summary and theoretical extension of the work design literature.

Science.gov (United States)

Humphrey, Stephen E; Nahrgang, Jennifer D; Morgeson, Frederick P

2007-09-01

The authors developed and meta-analytically examined hypotheses designed to test and extend work design theory by integrating motivational, social, and work context characteristics. Results from a summary of 259 studies and 219,625 participants showed that 14 work characteristics explained, on average, 43% of the variance in the 19 worker attitudes and behaviors examined. For example, motivational characteristics explained 25% of the variance in subjective performance, 2% in turnover perceptions, 34% in job satisfaction, 24% in organizational commitment, and 26% in role perception outcomes. Beyond motivational characteristics, social characteristics explained incremental variances of 9% of the variance in subjective performance, 24% in turnover intentions, 17% in job satisfaction, 40% in organizational commitment, and 18% in role perception outcomes. Finally, beyond both motivational and social characteristics, work context characteristics explained incremental variances of 4% in job satisfaction and 16% in stress. The results of this study suggest numerous opportunities for the continued development of work design theory and practice. (c) 2007 APA.

A meta-analysis of drug resistant tuberculosis in Sub-Saharan Africa: how strongly associated with previous treatment and HIV co-infection?

Science.gov (United States)

Berhan, Asres; Berhan, Yifru; Yizengaw, Desalegn

2013-11-01

In Sub-Saharan Africa, the fight against tuberculosis (TB) has encountered a great challenge because of the emergence of drug resistant TB strains and the high prevalence of HIV infection. The aim of this meta-analysis was to determine the association of drug-resistant TB with anti-TB drug treatment history and HIV co-infection. After electronic based literature search in the databases of Medline, HINARI, EMBASE and the Cochrane library, article selection and data extraction were carried out. HIV co-infection and previous history of TB treatment were used as predictors for the occurrence of any anti-TB drug resistant or multiple drug resistant TB (MDR-TB). The risk ratios for each included study and for the pooled sample were computed using the random-effects model. Heterogeneity test, sensitivity analyses and funnel plots were also done. The pooled analysis showed that the risk of developing drug-resistant TB to at least one anti-TB drug was about 3 times higher in individuals who had a previous history of anti-TB treatment than new TB cases. The risk of having MDR-TB in previously anti-TB treated TB cases was more than 5-fold higher than that of new TB cases. Resistance to Ethambutol and Rifampicin was more than fivefold higher among the previously treated with anti-TB drugs. However, HIV infection was not associated with drug-resistant TB. There was a strong association of previous anti-TB treatment with MDR-TB. Primary treatment warrants special emphasis, and screening for anti-TB drugs sensitivity has to be strengthened.

The Consequences of Perceived Discrimination for Psychological Well-Being : A Meta-Analytic Review

NARCIS (Netherlands)

Schmitt, Michael T.; Branscombe, Nyla R.; Postmes, Tom; Garcia, Amber

In 2 meta-analyses, we examined the relationship between perceived discrimination and psychological well-being and tested a number of moderators of that relationship. In Meta-Analysis 1 (328 independent effect sizes, N = 144,246), we examined correlational data measuring both perceived

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

A Meta-Analytic Review of Obesity Prevention in the Schools: 1997-2008

Science.gov (United States)

Cook-Cottone, Catherine; Casey, Carolyn M.; Feeley, Thomas Hugh; Baran, Jennifer

2009-01-01

A meta-analysis was conducted on school-based interventions to reduce obesity in children. Sixty-six (k = 66, N = 31,059) comparisons from 40 published studies from 1997 through 2008 were included in analyses. Results indicated a significant effect for school-based interventions with an overall weighted effect size of r = 0.05. Several moderating…

Figurative Language Comprehension in Individuals with Autism Spectrum Disorder: A Meta-Analytic Review

Science.gov (United States)

Kalandadze, Tamar; Norbury, Courtenay; Naerland, Terje; Naess, Kari-Anne B.

2018-01-01

We present a meta-analysis of studies that compare figurative language comprehension in individuals with autism spectrum disorder and in typically developing controls who were matched based on chronological age or/and language ability. A total of 41 studies and 45 independent effect sizes were included based on predetermined inclusion criteria.…

The Evaluation of Bivariate Mixed Models in Meta-analyses of Diagnostic Accuracy Studies with SAS, Stata and R.

Science.gov (United States)

Vogelgesang, Felicitas; Schlattmann, Peter; Dewey, Marc

2018-05-01

Meta-analyses require a thoroughly planned procedure to obtain unbiased overall estimates. From a statistical point of view not only model selection but also model implementation in the software affects the results. The present simulation study investigates the accuracy of different implementations of general and generalized bivariate mixed models in SAS (using proc mixed, proc glimmix and proc nlmixed), Stata (using gllamm, xtmelogit and midas) and R (using reitsma from package mada and glmer from package lme4). Both models incorporate the relationship between sensitivity and specificity - the two outcomes of interest in meta-analyses of diagnostic accuracy studies - utilizing random effects. Model performance is compared in nine meta-analytic scenarios reflecting the combination of three sizes for meta-analyses (89, 30 and 10 studies) with three pairs of sensitivity/specificity values (97%/87%; 85%/75%; 90%/93%). The evaluation of accuracy in terms of bias, standard error and mean squared error reveals that all implementations of the generalized bivariate model calculate sensitivity and specificity estimates with deviations less than two percentage points. proc mixed which together with reitsma implements the general bivariate mixed model proposed by Reitsma rather shows convergence problems. The random effect parameters are in general underestimated. This study shows that flexibility and simplicity of model specification together with convergence robustness should influence implementation recommendations, as the accuracy in terms of bias was acceptable in all implementations using the generalized approach. Schattauer GmbH.

Effect of exercise interventions on perceived fatigue in people with multiple sclerosis: synthesis of meta-analytic reviews.

Science.gov (United States)

Safari, Reza; Van der Linden, Marietta L; Mercer, Tom H

2017-06-01

Although exercise training has been advocated as a nonpharmacological treatment for multiple sclerosis (MS) related fatigue, no consensus exists regarding its effectiveness. To address this, we collated meta-analytic reviews that explored the effectiveness of exercise training for the treatment of MS-related fatigue. We searched five online databases for relevant reviews, published since 2005, and identified 172 records. Five reviews were retained for systematic extraction of information and evidence quality analysis. Although our review synthesis indicated that exercise training interventions have a moderate effect on fatigue reduction in people with MS, no clear insight was obtained regarding the relative effectiveness of specific types or modes of exercise intervention. Moreover, Grading of Recommendation Assessment, Development and Evaluation revealed that the overall quality of evidence emanating from these five reviews was 'very low'.

Spatial Bayesian latent factor regression modeling of coordinate-based meta-analysis data.

Science.gov (United States)

Montagna, Silvia; Wager, Tor; Barrett, Lisa Feldman; Johnson, Timothy D; Nichols, Thomas E

2018-03-01

Now over 20 years old, functional MRI (fMRI) has a large and growing literature that is best synthesised with meta-analytic tools. As most authors do not share image data, only the peak activation coordinates (foci) reported in the article are available for Coordinate-Based Meta-Analysis (CBMA). Neuroimaging meta-analysis is used to (i) identify areas of consistent activation; and (ii) build a predictive model of task type or cognitive process for new studies (reverse inference). To simultaneously address these aims, we propose a Bayesian point process hierarchical model for CBMA. We model the foci from each study as a doubly stochastic Poisson process, where the study-specific log intensity function is characterized as a linear combination of a high-dimensional basis set. A sparse representation of the intensities is guaranteed through latent factor modeling of the basis coefficients. Within our framework, it is also possible to account for the effect of study-level covariates (meta-regression), significantly expanding the capabilities of the current neuroimaging meta-analysis methods available. We apply our methodology to synthetic data and neuroimaging meta-analysis datasets. © 2017, The International Biometric Society.

Spatial Bayesian Latent Factor Regression Modeling of Coordinate-based Meta-analysis Data

Science.gov (United States)

Montagna, Silvia; Wager, Tor; Barrett, Lisa Feldman; Johnson, Timothy D.; Nichols, Thomas E.

2017-01-01

Summary Now over 20 years old, functional MRI (fMRI) has a large and growing literature that is best synthesised with meta-analytic tools. As most authors do not share image data, only the peak activation coordinates (foci) reported in the paper are available for Coordinate-Based Meta-Analysis (CBMA). Neuroimaging meta-analysis is used to 1) identify areas of consistent activation; and 2) build a predictive model of task type or cognitive process for new studies (reverse inference). To simultaneously address these aims, we propose a Bayesian point process hierarchical model for CBMA. We model the foci from each study as a doubly stochastic Poisson process, where the study-specific log intensity function is characterised as a linear combination of a high-dimensional basis set. A sparse representation of the intensities is guaranteed through latent factor modeling of the basis coefficients. Within our framework, it is also possible to account for the effect of study-level covariates (meta-regression), significantly expanding the capabilities of the current neuroimaging meta-analysis methods available. We apply our methodology to synthetic data and neuroimaging meta-analysis datasets. PMID:28498564

Protocol-developing meta-ethnography reporting guidelines (eMERGe).

Science.gov (United States)

France, E F; Ring, N; Noyes, J; Maxwell, M; Jepson, R; Duncan, E; Turley, R; Jones, D; Uny, I

2015-11-25

Designing and implementing high-quality health care services and interventions requires robustly synthesised evidence. Syntheses of qualitative research studies can provide evidence of patients' experiences of health conditions; intervention feasibility, appropriateness and acceptability to patients; and advance understanding of health care issues. The unique, interpretive, theory-based meta-ethnography synthesis approach is suited to conveying patients' views and developing theory to inform service design and delivery. However, meta-ethnography reporting is often poor quality, which discourages trust in, and use of, meta-ethnography findings. Users of evidence syntheses require reports that clearly articulate analytical processes and findings. Tailored research reporting guidelines can raise reporting standards but none exists for meta-ethnography. This study aims to create an evidence-based meta-ethnography reporting guideline articulating the methodological standards and depth of reporting required to improve reporting quality. The mixed-methods design of this National Institute of Health Research-funded study (http://www.stir.ac.uk/emerge/) follows good practice in research reporting guideline development comprising: (1) a methodological systematic review (PROSPERO registration: CRD42015024709) to identify recommendations and guidance in conducting/reporting meta-ethnography; (2) a review and audit of published meta-ethnographies to identify good practice principles and develop standards in conduct/reporting; (3) an online workshop and Delphi studies to agree guideline content with 45 international qualitative synthesis experts and 45 other stakeholders including patients; (4) development and wide dissemination of the guideline and its accompanying detailed explanatory document, a report template for National Institute of Health Research commissioned meta-ethnographies, and training materials on guideline use. Meta-ethnography, devised in the field of education

The Effect of Gender on Organizational Commitment of Teachers: A Meta Analytic Analysis

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Aydin, Ayhan; Sarier, Yilmaz; Uysal, Sengul

2011-01-01

The purpose of this study is to determine the effect of gender on the organizational commitment of teachers. In this respect, the levels of organizational commitment were also investigated with organizational commitment. Fifteen master and doctorate theses done between 2005-2009 were analyzed using meta analysis. At the end of the research study,…

The Trans-Contextual Model of Autonomous Motivation in Education: Conceptual and Empirical Issues and Meta-Analysis.

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Hagger, Martin S; Chatzisarantis, Nikos L D

2016-06-01

The trans-contextual model outlines the processes by which autonomous motivation toward activities in a physical education context predicts autonomous motivation toward physical activity outside of school, and beliefs about, intentions toward, and actual engagement in, out-of-school physical activity. In the present article, we clarify the fundamental propositions of the model and resolve some outstanding conceptual issues, including its generalizability across multiple educational domains, criteria for its rejection or failed replication, the role of belief-based antecedents of intentions, and the causal ordering of its constructs. We also evaluate the consistency of model relationships in previous tests of the model using path-analytic meta-analysis. The analysis supported model hypotheses but identified substantial heterogeneity in the hypothesized relationships across studies unattributed to sampling and measurement error. Based on our meta-analysis, future research needs to provide further replications of the model in diverse educational settings beyond physical education and test model hypotheses using experimental methods.

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

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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.

Social Goals and Youth Aggression: Meta-Analysis of Prosocial and Antisocial Goals

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Samson, Jennifer E.; Ojanen, Tiina; Hollo, Alexandra

2012-01-01

To advance research evaluating the relationship between social information processing (Crick & Dodge) and youth aggression, this meta-analytic study examined associations between social goals and aggression in children in 21 separate research reports. Eligible studies provided descriptive or preintervention measurement of children's aggression and…

VAGINAL PROGESTERONE VERSUS CERVICAL CERCLAGE FOR THE PREVENTION OF PRETERM BIRTH IN WOMEN WITH A SONOGRAPHIC SHORT CERVIX, SINGLETON GESTATION, AND PREVIOUS PRETERM BIRTH: A SYSTEMATIC REVIEW AND INDIRECT COMPARISON META-ANALYSIS

Science.gov (United States)

CONDE-AGUDELO, Agustin; ROMERO, Roberto; NICOLAIDES, Kypros; CHAIWORAPONGSA, Tinnakorn; O'BRIEN, John M.; CETINGOZ, Elcin; DA FONSECA, Eduardo; CREASY, George; SOMA-PILLAY, Priya; FUSEY, Shalini; CAM, Cetin; ALFIREVIC, Zarko; HASSAN, Sonia S.

2012-01-01

OBJECTIVE No randomized controlled trial has directly compared vaginal progesterone and cervical cerclage for the prevention of preterm birth in women with a sonographic short cervix in the midtrimester, singleton gestation, and previous spontaneous preterm birth. We performed an indirect comparison of vaginal progesterone versus cerclage, using placebo/no cerclage as the common comparator. STUDY DESIGN Adjusted indirect meta-analysis of randomized controlled trials. RESULTS Four studies evaluating vaginal progesterone versus placebo (158 patients) and five evaluating cerclage versus no cerclage (504 patients) were included. Both interventions were associated with a statistically significant reduction in the risk of preterm birth <32 weeks of gestation and composite perinatal morbidity and mortality compared with placebo/no cerclage. Adjusted indirect meta-analyses did not show statistically significant differences between vaginal progesterone and cerclage in reducing preterm birth or adverse perinatal outcomes. CONCLUSION Based on state-of-the-art methodology for indirect comparisons, either vaginal progesterone or cerclage are equally efficacious in the prevention of preterm birth in women with a sonographic short cervix in the midtrimester, singleton gestation, and previous preterm birth. The selection of the optimal treatment may depend upon adverse events, cost and patient/clinician preferences. PMID:23157855

Inhibition deficits in individuals with intellectual disability: a meta-regression analysis

NARCIS (Netherlands)

Bexkens, A.; Ruzzano, L.; Collot D'Escury-Koenigs, A.M.L.; van der Molen, M.W.; Huizenga, H.M.

2014-01-01

Background: Individuals with intellectual disabilities (ID) are characterised by inhibition deficits; however, the magnitude of these deficits is still subject to debate. This meta-analytic study therefore has two aims: first to assess the magnitude of inhibition deficits in ID, and second to

Can infants learn phonology in the lab? A meta-analytic answer.

Science.gov (United States)

Cristia, Alejandrina

2018-01-01

Two of the key tasks facing the language-learning infant lie at the level of phonology: establishing which sounds are contrastive in the native inventory, and determining what their possible syllabic positions and permissible combinations (phonotactics) are. In 2002-2003, two theoretical proposals, one bearing on how infants can learn sounds (Maye, Werker, & Gerken, 2002) and the other on phonotactics (Chambers, Onishi, & Fisher, 2003), were put forward on the pages of Cognition, each supported by two laboratory experiments, wherein a group of infants was briefly exposed to a set of pseudo-words, and plausible phonological generalizations were tested subsequently. These two papers have received considerable attention from the general scientific community, and inspired a flurry of follow-up work. In the context of questions regarding the replicability of psychological science, the present work uses a meta-analytic approach to appraise extant empirical evidence for infant phonological learning in the laboratory. It is found that neither seminal finding (on learning sounds and learning phonotactics) holds up when close methodological replications are integrated, although less close methodological replications do provide some evidence in favor of the sound learning strand of work. Implications for authors and readers of this literature are drawn out. It would be desirable that additional mechanisms for phonological learning be explored, and that future infant laboratory work employ paradigms that rely on constrained and unambiguous links between experimental exposure and measured infant behavior. Copyright © 2017. Published by Elsevier B.V.

Balancing selection and heterogeneity across the classical human leukocyte antigen loci: a meta-analytic review of 497 population studies.

Science.gov (United States)

Solberg, Owen D; Mack, Steven J; Lancaster, Alex K; Single, Richard M; Tsai, Yingssu; Sanchez-Mazas, Alicia; Thomson, Glenys

2008-07-01

This paper presents a meta-analysis of high-resolution human leukocyte antigen (HLA) allele frequency data describing 497 population samples. Most of the datasets were compiled from studies published in eight journals from 1990 to 2007; additional datasets came from the International Histocompatibility Workshops and from the AlleleFrequencies.net database. In all, these data represent approximately 66,800 individuals from throughout the world, providing an opportunity to observe trends that may not have been evident at the time the data were originally analyzed, especially with regard to the relative importance of balancing selection among the HLA loci. Population genetic measures of allele frequency distributions were summarized across populations by locus and geographic region. A role for balancing selection maintaining much of HLA variation was confirmed. Further, the breadth of this meta-analysis allowed the ranking of the HLA loci, with DQA1 and HLA-C showing the strongest balancing selection and DPB1 being compatible with neutrality. Comparisons of the allelic spectra reported by studies since 1990 indicate that most of the HLA alleles identified since 2000 are very-low-frequency alleles. The literature-based allele-count data, as well as maps summarizing the geographic distributions for each allele, are available online.

Flaws in animal studies exploring statins and impact on meta-analysis.

Science.gov (United States)

Moja, Lorenzo; Pecoraro, Valentina; Ciccolallo, Laura; Dall'Olmo, Luigi; Virgili, Gianni; Garattini, Silvio

2014-06-01

Animal experiments should be appropriately designed, correctly analysed and transparently reported to increase their scientific validity and maximise the knowledge gained from each experiment. This systematic review of animal experiments investigating statins evaluates their quality of reporting and methodological aspects as well as their implications for the conduction of meta-analyses. We searched medline and embase for studies reporting research on statins in mice, rats and rabbits. We collected detailed information about the characteristics of studies, animals and experimental methods. We retrieved 161 studies. A little over half did not report randomisation (55%) and most did not describe blinding (88%). All studies reported details on the experimental procedure, although many omitted information about animal gender, age or weight. Four percent did not report the number of animals used. None reported the sample size. Fixed- and random-effects models gave different results (ratio of effect size increased by five folds). Heterogeneity was consistently substantial within animal models, for which accounting for covariates had minimal impact. Publication bias is highly suspected across studies. Although statins showed efficacy in animal models, preclinical studies highlighted fundamental problems in the way in which such research is conducted and reported. Results were often difficult to interpret and reproduce. Different meta-analytic approaches were highly inconsistent: a reliable approach to estimate the true parameter was imperceptible. Policies that address these issues are required from investigators, editors and institutions that care about the quality standards and ethics of animal research. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.

Meta-análise em pesquisas científicas: enfoque em metodologias Meta analysis in scientific research: a methodological approach

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P.A. Lovatto

2007-07-01

meta-analytic studies are described (selection, code, data filtration. The most common analysis (graph, adjustments are presented, the choice of the statistical model (a qualitative explanatory factor, a qualitative or quantitative effect, the interference factors and the post-analytic procedures (residual variations, heterogeneity among results. In conclusion, this text shows that meta-analysis is better than traditional methods of literature review for esteeming with more precision the treatments effects adjusting it's for the experimental heterogeneity. However, the meta-analysis requires discipline in the systematization and analysis of the research results.

Pain anticipation: an activation likelihood estimation meta-analysis of brain imaging studies.

Science.gov (United States)

Palermo, Sara; Benedetti, Fabrizio; Costa, Tommaso; Amanzio, Martina

2015-05-01

The anticipation of pain has been investigated in a variety of brain imaging studies. Importantly, today there is no clear overall picture of the areas that are involved in different studies and the exact role of these regions in pain expectation remains especially unexploited. To address this issue, we used activation likelihood estimation meta-analysis to analyze pain anticipation in several neuroimaging studies. A total of 19 functional magnetic resonance imaging were included in the analysis to search for the cortical areas involved in pain anticipation in human experimental models. During anticipation, activated foci were found in the dorsolateral prefrontal, midcingulate and anterior insula cortices, medial and inferior frontal gyri, inferior parietal lobule, middle and superior temporal gyrus, thalamus, and caudate. Deactivated foci were found in the anterior cingulate, superior frontal gyrus, parahippocampal gyrus and in the claustrum. The results of the meta-analytic connectivity analysis provide an overall view of the brain responses triggered by the anticipation of a noxious stimulus. Such a highly distributed perceptual set of self-regulation may prime brain regions to process information where emotion, action and perception as well as their related subcategories play a central role. Not only do these findings provide important information on the neural events when anticipating pain, but also they may give a perspective into nocebo responses, whereby negative expectations may lead to pain worsening. © 2014 Wiley Periodicals, Inc.

Health message framing effects on attitudes, intentions, and behavior: a meta-analytic review.

Science.gov (United States)

Gallagher, Kristel M; Updegraff, John A

2012-02-01

Message framing has been an important focus in health communication research, yet prior meta-analyses found limited support for using framing to increase persuasiveness of health messages. This meta-analysis distinguished the outcomes used to assess the persuasive impact of framed messages (attitudes, intentions, or behavior). One hundred eighty-nine effect sizes were identified from 94 peer-reviewed, published studies which compared the persuasive impact of gain- and loss-framed messages. Gain-framed messages were more likely than loss-framed messages to encourage prevention behaviors (r = 0.083, p = 0.002), particularly for skin cancer prevention, smoking cessation, and physical activity. No effect of framing was found when persuasion was assessed by attitudes/intentions or among studies encouraging detection. Gain-framed messages appear to be more effective than loss-framed messages in promoting prevention behaviors. Research should examine the contexts in which loss-framed messages are most effective, and the processes that mediate the effects of framing on behavior.

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...

Neuroanatomic changes and their association with cognitive decline in mild cognitive impairment: a meta-analysis

OpenAIRE

Nickl-Jockschat, Thomas; Kleiman, Alexandra; Schulz, Jörg B.; Schneider, Frank; Laird, Angela R.; Fox, Peter T.; Eickhoff, Simon B.; Reetz, Kathrin

2011-01-01

Mild cognitive impairment (MCI) is an acquired syndrome characterised by cognitive decline not affecting activities of daily living. Using a quantitative meta-analytic approach, we aimed to identify consistent neuroanatomic correlates of MCI and how they are related to cognitive dysfunction. The meta-analysis enrols 22 studies, involving 917 MCI (848 amnestic MCI) patients and 809 healthy controls. Only studies investigating local changes in grey matter and reporting whole-brain results in st...

Does acute exercise affect the performance of whole-body, psychomotor skills in an inverted-U fashion? A meta-analytic investigation.

Science.gov (United States)

McMorris, Terry; Hale, Beverley J; Corbett, Jo; Robertson, Kevin; Hodgson, Christopher I

2015-03-15

The primary purpose of this study was to examine, using meta-analytical measures, whether research into the performance of whole-body, psychomotor tasks following moderate and heavy exercise demonstrates an inverted-U effect. A secondary purpose was to compare the effects of acute exercise on tasks requiring static maintenance of posture versus dynamic, ballistic skills. Moderate intensity exercise was determined as being between 40% and 79% maximum power output (ẆMAX) or equivalent, while ≥80% ẆMAX was considered to be heavy. There was a significant difference (Zdiff=4.29, p=0.001, R(2)=0.42) between the mean effect size for moderate intensity exercise (g=0.15) and that for heavy exercise size (g=-0.86). These data suggest a catastrophe effect during heavy exercise. Mean effect size for static tasks (g=-1.24) was significantly different (Zdiff=3.24, p=0.001, R(2)=0.90) to those for dynamic/ballistic tasks (g=-0.30). The result for the static versus dynamic tasks moderating variables point to perception being more of an issue than peripheral fatigue for maintenance of static posture. The difference between this result and those found in meta-analyses examining the effects of acute exercise on cognition shows that, when perception and action are combined, the complexity of the interaction induces different effects to when cognition is detached from motor performance. Copyright © 2015 Elsevier Inc. All rights reserved.

Dividend Policy and Corporate Value (A Meta-Analysis

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Tifani Titah Dwi Tyastari

2017-07-01

Full Text Available This study aimed to understand the effect of dividend policy on corporate value, as well as to examine and analyze the variation of result study on corporate value in Indonesia.Dividend Signaling Model was the grand theory used to explain the effect of dividend policy on corporate value. This study used meta-analysis approach with the sample were 70 researches in Indonesia, both the published and unpublished in 2007-2015. The result of this study, meta-analysis strengthens the findings of the previous study which stated that the dividend policy could increase the corporate value. The differences of the previous studies were due to the presence of moderation effect from the measurement model of corporate value and dividend corporate.

The price-perceived quality relationship: A meta-analytic review and assessment of its determinants

DEFF Research Database (Denmark)

Völckner, Franziska; Hofmann, Julian

2007-01-01

The authors conducted a meta-analysis of study results on the price-perceived quality relationship published from 1989 to 2006. The findings show that the price effect on perceived quality has decreased. Furthermore, the price–quality relationship is stronger in studies that use a within-subjects...

Effectiveness of Intelligent Tutoring Systems: A Meta-Analytic Review

Science.gov (United States)

Kulik, James A.; Fletcher, J. D.

2016-01-01

This review describes a meta-analysis of findings from 50 controlled evaluations of intelligent computer tutoring systems. The median effect of intelligent tutoring in the 50 evaluations was to raise test scores 0.66 standard deviations over conventional levels, or from the 50th to the 75th percentile. However, the amount of improvement found in…

Allocation plasticity and plant-metal partitioning: Meta-analytical perspectives in phytoremediation

Energy Technology Data Exchange (ETDEWEB)

Audet, Patrick [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie Street, Ottawa, ON K1N 6N5 (Canada)], E-mail: paude086@uottawa.ca; Charest, Christiane [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie Street, Ottawa, ON K1N 6N5 (Canada)], E-mail: ccharest@uottawa.ca

2008-11-15

In this meta-analysis of plant growth and metal uptake parameters, we selected 19 studies of heavy metal (HM) phytoremediation to evaluate trends of allocation plasticity and plant-metal partitioning in roots relative to shoots. We calculated indexes of biomass allocation and metal distribution for numerous metals and plant species among four families of interest for phytoremediation purposes (e.g. Brassicaceae, Fabaceae, Poaceae, and Solanaceae). We determined that plants shift their biomass and distribute metals more to roots than shoots possibly to circumvent the challenges of increasing soil-HM conditions. Although this shift is viewed as a stress-avoidance strategy complementing intrinsic stress-tolerance, our findings indicate that plants express different levels of allocation plasticity and metal partitioning depending on their overall growth strategy and status as 'fast-grower' or 'slow-grower' species. Accordingly, we propose a conceptual model of allocation plasticity and plant-metal partitioning comparing 'fast-grower' and 'slow-grower' strategies and outlining applications for remediation practices. - This meta-analysis has revealed a shift in plant biomass and metal distribution from shoots to roots possibly to protect vital functions when subjected to metal stress.

Allocation plasticity and plant-metal partitioning: Meta-analytical perspectives in phytoremediation

International Nuclear Information System (INIS)

Audet, Patrick; Charest, Christiane

2008-01-01

In this meta-analysis of plant growth and metal uptake parameters, we selected 19 studies of heavy metal (HM) phytoremediation to evaluate trends of allocation plasticity and plant-metal partitioning in roots relative to shoots. We calculated indexes of biomass allocation and metal distribution for numerous metals and plant species among four families of interest for phytoremediation purposes (e.g. Brassicaceae, Fabaceae, Poaceae, and Solanaceae). We determined that plants shift their biomass and distribute metals more to roots than shoots possibly to circumvent the challenges of increasing soil-HM conditions. Although this shift is viewed as a stress-avoidance strategy complementing intrinsic stress-tolerance, our findings indicate that plants express different levels of allocation plasticity and metal partitioning depending on their overall growth strategy and status as 'fast-grower' or 'slow-grower' species. Accordingly, we propose a conceptual model of allocation plasticity and plant-metal partitioning comparing 'fast-grower' and 'slow-grower' strategies and outlining applications for remediation practices. - This meta-analysis has revealed a shift in plant biomass and metal distribution from shoots to roots possibly to protect vital functions when subjected to metal stress

The consequences of perceived discrimination for psychological well-being: a meta-analytic review.

Science.gov (United States)

Schmitt, Michael T; Branscombe, Nyla R; Postmes, Tom; Garcia, Amber

2014-07-01

In 2 meta-analyses, we examined the relationship between perceived discrimination and psychological well-being and tested a number of moderators of that relationship. In Meta-Analysis 1 (328 independent effect sizes, N = 144,246), we examined correlational data measuring both perceived discrimination and psychological well-being (e.g., self-esteem, depression, anxiety, psychological distress, life satisfaction). Using a random-effects model, the mean weighted effect size was significantly negative, indicating harm (r = -.23). Effect sizes were larger for disadvantaged groups (r = -.24) compared to advantaged groups (r = -.10), larger for children compared to adults, larger for perceptions of personal discrimination compared to group discrimination, and weaker for racism and sexism compared to other stigmas. The negative relationship was significant across different operationalizations of well-being but was somewhat weaker for positive outcomes (e.g., self-esteem, positive affect) than for negative outcomes (e.g., depression, anxiety, negative affect). Importantly, the effect size was significantly negative even in longitudinal studies that controlled for prior levels of well-being (r = -.15). In Meta-Analysis 2 (54 independent effect sizes, N = 2,640), we examined experimental data from studies manipulating perceptions of discrimination and measuring well-being. We found that the effect of discrimination on well-being was significantly negative for studies that manipulated general perceptions of discrimination (d = -.25), but effects did not differ from 0 when attributions to discrimination for a specific negative event were compared to personal attributions (d = .06). Overall, results support the idea that the pervasiveness of perceived discrimination is fundamental to its harmful effects on psychological well-being. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Does sexy media promote teen sex? A meta-analytic and methodological review

OpenAIRE

Ferguson, Chris; Nielsen, Rune Kristian Lundedal; Markey, Patrick

2016-01-01

Parents and policy makers are often concerned that sexy media (media depicting or discussing sexual encounters) may promote sexual behavior in young viewers. There has been some debate among scholars regarding whether such media promote sexual behaviors. It remains unclear to what extent sexy media is a risk factor for increased sexual behavior among youth. The current study employed a meta-analysis of 22 correlational and longitudinal studies of sexy media effects on teen sexual behavior (n ...

Consumption of garlic and risk of colorectal cancer: an updated meta-analysis of prospective studies.

Science.gov (United States)

Hu, Ji-Yi; Hu, Yi-Wang; Zhou, Jiao-Jiao; Zhang, Meng-Wen; Li, Dan; Zheng, Shu

2014-11-07

To conduct an updated meta-analysis of prospective studies addressing the association between garlic consumption and colorectal cancer. Eligible cohort studies were identified by searching MEDLINE (PubMed) and screening the references of related articles published up to October 2013. Meta-analyses were conducted for colorectal cancer in relation to consumption of raw and cooked (RC) garlic and garlic supplements, separately. The summary relative risks (RR) with 95%CI were calculated using fixed-effects or random-effects model depending on the heterogeneity among studies. A total of 5 prospective cohort studies were identified. In contrast to the previous meta-analysis, no significant associations were found between consumption of RC garlic (RR: 1.06; 95%CI: 0.95-1.19) or garlic supplements (RR: 1.12; 95%CI: 0.96-1.31) and risk of colorectal cancer. A non-significant protective effect of garlic supplement intake against colorectal cancer was observed in females (RR: 0.84; 95%CI: 0.64-1.11), but the opposite was the case in males (RR: 1.24; 95%CI: 0.96-1.59). Consumption of RC garlic or garlic supplements is not significantly associated with reduced colorectal cancer risk.

Does gratitude enhance prosociality?: A meta-analytic review.

Science.gov (United States)

Ma, Lawrence K; Tunney, Richard J; Ferguson, Eamonn

2017-06-01

Theoretical models suggest that gratitude is linked to increased prosociality. To date, however, there is a lack of a comprehensive quantitative synthesis of results to support this claim. In this review we aimed to (a) examine the overall strength of the association between gratitude and prosociality, and (b) identify the theoretical and methodological variables that moderate this link. We identified 252 effect sizes from 91 studies across 65 papers-(Total N = 18,342 participants). The present meta-analysis revealed a statistically significant, and moderate positive correlation between gratitude and prosociality (r = .374). This association was significantly larger among studies that assessed reciprocal outcomes relative to nonreciprocal outcomes, and in particular among studies that examined direct -compared with indirect -reciprocity. Studies that examined gratitude as an affective state reported significantly larger effect size studies assessing gratitude as a trait . Studies that examined benefit-triggered gratitude (in response to other's kindness) had a stronger effect that generalized gratitude that focuses on the appreciation of what is valued and cherished in life. Finally, studies that manipulated gratitude in vivo (e.g., economic games) had larger effect sizes compared with those based on recalled incidents when the person felt grateful. We describe the theoretical and practical significance of the results. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Neuroimaging studies of practice-related change: fMRI and meta-analytic evidence of a domain-general control network for learning.

Science.gov (United States)

Chein, Jason M; Schneider, Walter

2005-12-01

Functional magnetic resonance imaging and a meta-analysis of prior neuroimaging studies were used to characterize cortical changes resulting from extensive practice and to evaluate a dual-processing account of the neural mechanisms underlying human learning. Three core predictions of the dual processing theory are evaluated: 1) that practice elicits generalized reductions in regional activity by reducing the load on the cognitive control mechanisms that scaffold early learning; 2) that these control mechanisms are domain-general; and 3) that no separate processing pathway emerges as skill develops. To evaluate these predictions, a meta-analysis of prior neuroimaging studies and a within-subjects fMRI experiment contrasting unpracticed to practiced performance in a paired-associate task were conducted. The principal effect of practice was found to be a reduction in the extent and magnitude of activity in a cortical network spanning bilateral dorsal prefrontal, left ventral prefrontal, medial frontal (anterior cingulate), left insular, bilateral parietal, and occipito-temporal (fusiform) areas. These activity reductions are shown to occur in common regions across prior neuroimaging studies and for both verbal and nonverbal paired-associate learning in the present fMRI experiment. The implicated network of brain regions is interpreted as a domain-general system engaged specifically to support novice, but not practiced, performance.

Values of natural and human-made wetlands: A meta-analysis

NARCIS (Netherlands)

Ghermandi, A.; van den Bergh, J.C.J.M.; Brander, L.M.; de Groot, H.L.F.; Nunes, P.A.L.D.

2010-01-01

The values of goods and services provided by wetland ecosystems are examined through a meta-analysis of an expanded database of wetland value estimates and with a focus on human-made wetlands. This study extends and improves upon previous meta-analyses of the wetland valuation literature in terms of

Cognitive Evaluation Theory: A Meta-Analytic Review of the Literature.

Science.gov (United States)

Rummel, Amy; Feinberg, Richard

1988-01-01

Employed meta-analysis to determine existence of the detrimental effects of extrinsic rewards on intrinsic motivation. Results showed that within strictly defined parameters the phenomenon concerning the detrimental effects of reward described in Deci's Cognitive Evaluation Theory did exist. (Author/NB)

Are all first-generation antipsychotics equally effective in treating schizophrenia? A meta-analysis of randomised, haloperidol-controlled trials.

Science.gov (United States)

Dold, Markus; Tardy, Magdolna; Samara, Myrto T; Li, Chunbo; Kasper, Siegfried; Leucht, Stefan

2016-04-01

Narrative, unsystematic reviews revealed no differences in efficacy between the various first-generation antipsychotics (FGAs) resulting in the psychopharmacological assumption of comparable efficacy between the different FGAs. We sought to determine if the assumption of comparable efficacy of all FGAs can be regarded as evidence-based using meta-analytic statistics. A systematic literature survey (Cochrane Schizophrenia Group trial register) was applied to identify all RCTs that compared oral haloperidol with another oral FGA in schizophrenia. Primary outcome was dichotomous treatment response. Secondary outcomes were symptom severity measured by rating scales, discontinuation rates, and specific adverse effects. Altogether, 79 RCTs with 4343 participants published between 1962 and 1999 were included. We found a significant between-group difference only between haloperidol and nemonapride, but not for the remaining 19 investigated FGAs. There were no significant differences for discontinuation rates. As most of the single meta-analytic comparisons can be regarded as underpowered, the evidence for the assumption of comparable efficacy of all FGAs is inconclusive. We therefore cannot confirm or reject the statements of previous narrative, unsystematic reviews in this regard. Our findings were limited by the small sample size in the individual comparisons and the low methodological quality in many included studies.

Prevalence of traumatic brain injury in juvenile offenders: a meta-analysis.

Science.gov (United States)

Farrer, Thomas J; Frost, R Brock; Hedges, Dawson W

2013-01-01

Studies of traumatic brain injury (TBI) among adult populations demonstrate that such injuries can lead to aggressive behaviors. Related findings suggest that incarcerated individuals have high rates of brain injuries. Such studies suggest that traumatic brain injury may be related to the etiology and recidivism of criminal behavior. Relatively few studies have examined the prevalence of TBI using a delinquent juvenile sample. In order to assess the relationship between TBI and juvenile offender status, the current study used meta-analytic techniques to examine the odds of having a TBI among juvenile offenders. Across 9 studies, we found that approximately 30% of juvenile offenders have sustained a previous brain injury. Across 5 studies that used a control group, a calculated summary odds ratio of 3.37 suggests that juvenile offenders are significantly more likely to have a TBI compared to controls. Results suggest that the rate of TBIs within the juvenile offender population is significant and that there may be a relationship between TBIs and juvenile criminal behavior.

Periodontal Disease and Incident Lung Cancer Risk: A Meta-Analysis of Cohort Studies.

Science.gov (United States)

Zeng, Xian-Tao; Xia, Ling-Yun; Zhang, Yong-Gang; Li, Sheng; Leng, Wei-Dong; Kwong, Joey S W

2016-10-01

Periodontal disease is linked to a number of systemic diseases such as cardiovascular diseases and diabetes mellitus. Recent evidence has suggested periodontal disease might be associated with lung cancer. However, their precise relationship is yet to be explored. Hence, this study aims to investigate the association of periodontal disease and risk of incident lung cancer using a meta-analytic approach. PubMed, Scopus, and ScienceDirect were searched up to June 10, 2015. Cohort and nested case-control studies investigating risk of lung cancer in patients with periodontal disease were included. Hazard ratios (HRs) were calculated, as were their 95% confidence intervals (CIs) using a fixed-effect inverse-variance model. Statistical heterogeneity was explored using the Q test as well as the I(2) statistic. Publication bias was assessed by visual inspection of funnel plots symmetry and Egger's test. Five cohort studies were included, involving 321,420 participants in this meta-analysis. Summary estimates based on adjusted data showed that periodontal disease was associated with a significant risk of lung cancer (HR = 1.24, 95% CI = 1.13 to 1.36; I(2) = 30%). No publication bias was detected. Subgroup analysis indicated that the association of periodontal disease and lung cancer remained significant in the female population. Evidence from cohort studies suggests that patients with periodontal disease are at increased risk of developing lung cancer.

Does psychotherapy work with school-aged youth? A meta-analytic examination of moderator variables that influence therapeutic outcomes.

Science.gov (United States)

Fedewa, Alicia L; Ahn, Soyeon; Reese, Robert J; Suarez, Marietta M; Macquoid, Ahjane; Davis, Matthew C; Prout, H Thompson

2016-06-01

The present study is a quantitative synthesis of the available literature to investigate the efficacy of psychotherapy for children's mental health outcomes. In particular, this study focuses on potential moderating variables-study design, treatment, client, and therapist characteristics-that may influence therapeutic outcomes for youth but have not been thoroughly accounted for in prior meta-analytic studies. An electronic search of relevant databases resulted in 190 unpublished and published studies that met criteria for inclusion in the analysis. Effect sizes differed by study design. Pre-post-test designs resulted in absolute magnitudes of treatment effects ranging from |-0.02| to |-0.76| while treatment versus control group comparison designs resulted in absolute magnitudes of treatment effects ranging from |-0.14| to |-2.39|. Changes in youth outcomes larger than 20% were found, irrespective of study design, for outcomes focused on psychosomatization (29% reduction), school attendance (25% increase), and stress (48% reduction). The magnitude of changes after psychotherapy ranged from 6% (externalizing problems) to 48% (stress). Several moderator variables significantly influenced psychotherapy treatment effect sizes, including frequency and length of treatment as well as treatment format. However, results did not support the superiority of a single type of intervention for most outcomes. Implications for therapy with school-aged youth and future research are discussed. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry

OpenAIRE

Segerstrom, Suzanne C.; Miller, Gregory E.

2004-01-01

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stres...

Rational Emotive Therapy with Children and Adolescents: A Meta-Analysis

Science.gov (United States)

Gonzalez, Jorge E.; Nelson, J. Ron; Gutkin, Terry B.; Saunders, Anita; Galloway, Ann; Shwery, Craig S.

2004-01-01

This article systematically reviews the available research on rational emotive behavioral therapy (REBT) with children and adolescents. Meta-analytic procedures were applied to 19 studies that met inclusion criteria. The overall mean weighted effect of REBT was positive and significant. Weighted z[r] effect sizes were also computed for five…

Dairy consumption is inversely associated with type 2 diabetes: dose-response meta-analysis of prospective cohort studies

NARCIS (Netherlands)

Gijsbers, L.; Geleijnse, J.M.; Soedamah-Muthu, S.S.

2011-01-01

Observational studies suggest an inverse association between dairy intake and incident type 2 diabetes, but the quantity of dairy is not known. Previous meta-analyses did not take into account the type of dairy product. Therefore, we examined dose-response associations between the intake of total

Study protocol for examining job strain as a risk factor for severe unipolar depression in an individual participant meta-analysis of 14 European cohorts

DEFF Research Database (Denmark)

Madsen, Ida E H; Hannerz, Harald; Nyberg, Solja T

2013-01-01

scales that do not necessarily correspond to clinically diagnosed depression. In addition, a meta-analysis from 2008 indicated publication bias in the field. METHODS: This study protocol describes the planned design and analyses of an individual participant data meta-analysis, to examine whether job...... using random effects meta-analysis. DISCUSSION: The planned analyses will help clarify whether job strain is associated with an increased risk of clinically diagnosed unipolar depression. As the analysis is based on pre-planned study protocols and an individual participant data meta-analysis, the pooled......BACKGROUND: Previous studies have shown that gainfully employed individuals with high work demands and low control at work (denoted "job strain") are at increased risk of common mental disorders, including depression. Most existing studies have, however, measured depression using self-rated symptom...

Living with a Colicky Infant: Meta-synthesis of Qualitative Studies

Directory of Open Access Journals (Sweden)

Ali Reza Mansourzadeh

2016-08-01

Full Text Available Background Parents having a baby with infantile colic experienced thoughts and emotions such as hopelessness, fatigue and concern. This study presents a review to provide better insights into the life of parents living with a colicky infant. The aimed of this meta-synthesis was to analyze and synthesize findings from qualitative studies about the experiences of parents of colicky infants. Materials and Methods This meta-synthesis follows the guidelines of Sandeowski and Barroso and was designed to synthesize findings from previous qualitative studies. The following biomedical archives were searched: PubMED, Web of Science, PsycINFO, Cochrane library, ProQuest. Recently published articles and books on the experiences of parents living with a colicky infant were reviewed. The searches covered the years from 2000 to 2016 and found three studies, which fulfilled the inclusion criteria. Results The findings of all studies selected were categorized into the themes of "eclipse of normal life" and "relief through parental adaptation". The findings reveal that the experiences of parents living with a colicky infant are important for constructing an insightful child care protocol and improving interpersonal interactions in the family. Conclusion The pathic or non-diagnostic knowledge that emerged from this qualitative review may be helpful for improving treatment of colicky infants and a provide relief for their parents.

Estimation of the biserial correlation and its sampling variance for use in meta-analysis.

Science.gov (United States)

Jacobs, Perke; Viechtbauer, Wolfgang

2017-06-01

Meta-analyses are often used to synthesize the findings of studies examining the correlational relationship between two continuous variables. When only dichotomous measurements are available for one of the two variables, the biserial correlation coefficient can be used to estimate the product-moment correlation between the two underlying continuous variables. Unlike the point-biserial correlation coefficient, biserial correlation coefficients can therefore be integrated with product-moment correlation coefficients in the same meta-analysis. The present article describes the estimation of the biserial correlation coefficient for meta-analytic purposes and reports simulation results comparing different methods for estimating the coefficient's sampling variance. The findings indicate that commonly employed methods yield inconsistent estimates of the sampling variance across a broad range of research situations. In contrast, consistent estimates can be obtained using two methods that appear to be unknown in the meta-analytic literature. A variance-stabilizing transformation for the biserial correlation coefficient is described that allows for the construction of confidence intervals for individual coefficients with close to nominal coverage probabilities in most of the examined conditions. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

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.

Identifying Organizational Identification as a Basis for Attitudes and Behaviors: A Meta-Analytic Review.

Science.gov (United States)

Lee, Eun-Suk; Park, Tae-Youn; Koo, Bonjin

2015-09-01

Organizational identification has been argued to have a unique value in explaining individual attitudes and behaviors in organizations, as it involves the essential definition of entities (i.e., individual and organizational identities). This review seeks meta-analytic evidence of the argument by examining how this identity-relevant construct functions in the nexus of attitudinal/behavioral constructs. The findings show that, first, organizational identification is significantly associated with key attitudes (job involvement, job satisfaction, and affective organizational commitment) and behaviors (in-role performance and extra-role performance) in organizations. Second, in the classic psychological model of attitude-behavior relations (Fishbein & Ajzen, 1975), organizational identification is positioned as a basis from which general sets of those attitudes and behaviors are engendered; organizational identification has a direct effect on general behavior above and beyond the effect of general attitude. Third, the effects of organizational identification are moderated by national culture, a higher-level social context wherein the organization is embedded, such that the effects are stronger in a collectivistic culture than in an individualistic culture. Theoretical and practical implications of the findings and future research directions are discussed. (c) 2015 APA, all rights reserved).

How Acute Total Sleep Loss Affects the Attending Brain: A Meta-Analysis of Neuroimaging Studies

Science.gov (United States)

Ma, Ning; Dinges, David F.; Basner, Mathias; Rao, Hengyi

2015-01-01

Study Objectives: Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Design: Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. Methods: The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. Results: The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Conclusion: Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. Citation: Ma N, Dinges DF, Basner M, Rao H. How acute total

A meta-analytic review of life cycle assessment and flow analyses studies of palm oil biodiesel.

Science.gov (United States)

Manik, Yosef; Halog, Anthony

2013-01-01

This work reviews and performs a meta-analysis of the recent life cycle assessment and flow analyses studies palm oil biodiesel. The best available data and information are extracted, summarized, and discussed. Most studies found palm oil biodiesel would produce positive energy balance with an energy ratio between 2.27 and 4.81, and with a net energy production of 112 GJ ha(-1) y(-1). With the exception of a few studies, most conclude that palm oil biodiesel is a net emitter of greenhouse gases (GHG). The origin of oil palm plantation (planted area) is the foremost determinant of GHG emissions and C payback time (CPBT). Converting peatland forest results in GHG emissions up to 60 tons CO(2) equivalent (eq) ha(-1) y(-1) leading to 420 years of CPBT. In contrast, converting degraded land or grassland for plantation can positively offset the system to become a net sequester of 5 tons CO(2) eq ha(-1) y(-1). Few studies have discussed cradle-to-grave environmental impacts such as acidification, eutrophication, toxicity, and biodiversity, which open opportunity for further studies. Copyright © 2012 SETAC.

Psychological functioning of people living with chronic pain: a meta-analytic review.

Science.gov (United States)

Burke, Anne L J; Mathias, Jane L; Denson, Linley A

2015-09-01

Chronic pain (CP; >3 months) is a common condition that is associated with significant psychological problems. Many people with CP do not fit into discrete diagnostic categories, limiting the applicability of research that is specific to a particular pain diagnosis. This meta-analysis synthesized the large extant literature from a general CP, rather than diagnosis-specific, perspective to systematically identify and compare the psychological problems most commonly associated with CP. Four databases were searched from inception to December 2013 (PsychINFO, The Cochrane Library, Scopus, and PubMed) for studies comparing the psychological functioning of adults with CP to healthy controls. Data from 110 studies were meta-analysed and Cohen's d effect sizes calculated. The CP group reported experiencing significant problems in a range of psychological domains (depression, anxiety, somatization, anger/hostility, self-efficacy, self-esteem and general emotional functioning), with the largest effects observed for pain anxiety/concern and somatization; followed by anxiety and self-efficacy; and then depression, anger/hostility, self-esteem and general emotional functioning. This study demonstrates, for the first time, that individuals with CP are more likely to experience physically focussed psychological problems than other psychological problems and that, unlike self-efficacy, fear of pain is intrinsically tied to the CP experience. This challenges the prevailing view that, for individuals with CP, problems with depression are either equal to, or greater than, problems with anxiety, thereby providing important information to guide therapeutic targets. Positive clinical implications: This is the first time that the CP literature has been synthesized from a general perspective to examine psychological functioning in the presence of CP and provide practical recommendations for assessment and therapy. Individuals with CP were most likely to experience psychological problems

The effect of testing versus restudy on retention: a meta-analytic review of the testing effect.

Science.gov (United States)

Rowland, Christopher A

2014-11-01

Engaging in a test over previously studied information can serve as a potent learning event, a phenomenon referred to as the testing effect. Despite a surge of research in the past decade, existing theories have not yet provided a cohesive account of testing phenomena. The present study uses meta-analysis to examine the effects of testing versus restudy on retention. Key results indicate support for the role of effortful processing as a contributor to the testing effect, with initial recall tests yielding larger testing benefits than recognition tests. Limited support was found for existing theoretical accounts attributing the testing effect to enhanced semantic elaboration, indicating that consideration of alternative mechanisms is warranted in explaining testing effects. Future theoretical accounts of the testing effect may benefit from consideration of episodic and contextually derived contributions to retention resulting from memory retrieval. Additionally, the bifurcation model of the testing effect is considered as a viable framework from which to characterize the patterns of results present across the literature. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Managing complex research datasets using electronic tools: A meta-analysis exemplar

Science.gov (United States)

Brown, Sharon A.; Martin, Ellen E.; Garcia, Theresa J.; Winter, Mary A.; García, Alexandra A.; Brown, Adama; Cuevas, Heather E.; Sumlin, Lisa L.

2013-01-01

Meta-analyses of broad scope and complexity require investigators to organize many study documents and manage communication among several research staff. Commercially available electronic tools, e.g., EndNote, Adobe Acrobat Pro, Blackboard, Excel, and IBM SPSS Statistics (SPSS), are useful for organizing and tracking the meta-analytic process, as well as enhancing communication among research team members. The purpose of this paper is to describe the electronic processes we designed, using commercially available software, for an extensive quantitative model-testing meta-analysis we are conducting. Specific electronic tools improved the efficiency of (a) locating and screening studies, (b) screening and organizing studies and other project documents, (c) extracting data from primary studies, (d) checking data accuracy and analyses, and (e) communication among team members. The major limitation in designing and implementing a fully electronic system for meta-analysis was the requisite upfront time to: decide on which electronic tools to use, determine how these tools would be employed, develop clear guidelines for their use, and train members of the research team. The electronic process described here has been useful in streamlining the process of conducting this complex meta-analysis and enhancing communication and sharing documents among research team members. PMID:23681256

The Road to Forgiveness: A Meta-Analytic Synthesis of Its Situational and Dispositional Correlates

Science.gov (United States)

Fehr, Ryan; Gelfand, Michele J.; Nag, Monisha

2010-01-01

Forgiveness has received widespread attention among psychologists from social, personality, clinical, developmental, and organizational perspectives alike. Despite great progress, the forgiveness literature has witnessed few attempts at empirical integration. Toward this end, we meta-analyze results from 175 studies and 26,006 participants to…

The relations between parents’ big five personality factors and parenting: a meta-analytic review

NARCIS (Netherlands)

Prinzie, P.; Stams, G.J.J.M.; Dekovic, M.; Reijntjes, A.H.A.; Belsky, J.

2009-01-01

To investigate the association between Big Five personality factors and three dimensions of parenting-warmth, behavioral control, and autonomy support- the authors conducted meta-analyses using 5,853 parent-child dyads that were included in 30 studies. Effect sizes were significant and robust across

Preventing postpartum depression: A meta-analytic review

Science.gov (United States)

Sockol, Laura E.; Epperson, C. Neill; Barber, Jacques P.

2014-01-01

This meta-analysis assessed the efficacy of a wide range of preventive interventions designed to reduce the severity of postpartum depressive symptoms or decrease the prevalence of postpartum depressive episodes. A systematic review identified 37 randomized or quasi-randomized controlled trials in which an intervention was compared to a control condition. Differences between treatment and control conditions in the level of depressive symptoms and prevalence of depressive episodes by 6 months postpartum were assessed in separate analyses. Depressive symptoms were significantly lower at post-treatment in intervention conditions, with an overall effect size in the small range after exclusion of outliers (Hedges' g = 0.18). There was a 27% reduction in the prevalence of depressive episodes in intervention conditions by 6 months postpartum after removal of outliers and correction for publication bias. Later timing of the postpartum assessment was associated with smaller differences between intervention and control conditions in both analyses. Among studies that assessed depressive symptoms using the EPDS, higher levels of depressive symptoms at pre-treatment were associated with smaller differences in depressive symptoms by 6 months postpartum. These findings suggest that interventions designed to prevent postpartum depression effectively reduce levels of postpartum depressive symptoms and decrease risk for postpartum depressive episodes. PMID:24211712

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.

The Effects of Exercise on Abdominal Fat and Liver Enzymes in Pediatric Obesity: A Systematic Review and Meta-Analysis.

Science.gov (United States)

González-Ruiz, Katherine; Ramírez-Vélez, Robinson; Correa-Bautista, Jorge Enrique; Peterson, Mark D; García-Hermoso, Antonio

2017-08-01

Despite the prevalence of obesity and the multiple position stands promoting exercise for the treatment of obesity and hepatic function, a meta-analytic approach has not previously been used to examine the effects in the pediatric population. The aim of the study was to determine the effectiveness of exercise interventions on abdominal fat, liver enzymes, and intrahepatic fat in overweight and obese youth. A computerized search was made using three databases. The analysis was restricted to studies that examined the effect of supervised exercise interventions on abdominal fat (visceral and subcutaneous fat), liver enzymes (alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase), and intrahepatic fat. Fourteen clinical trials (1231 youths) were eligible for inclusion in this systematic review and meta-analysis. Standardized mean difference [SMD] and 95% confidence intervals (CIs) were calculated. Exercise was associated with a significant reduction in visceral (SMD = -0.661; 95% CI, -0.976 to -0.346; p exercise programs that involve aerobic exercise longer than three sessions per week. This meta-analysis supports current recommendation for physical exercise, mainly aerobic, as an effective intervention for nonalcoholic fatty liver disease progression by targeting hepatic lipid composition, visceral and subcutaneous adipose tissue. Systematic review registration: PROSPERO CRD42016042163.

A meta-analytic review on social relationships and suicidal ideation among older adults.

Science.gov (United States)

Chang, Qingsong; Chan, Chee Hon; Yip, Paul S F

2017-10-01

Social relationships play an important role in mental health as well as suicidal ideation in later life. In contrast with the other well-established risk factors, despite an increasing number of related studies, no meta-analyses focusing on social relationships and late-life suicidal ideation have been published. Synthesis of data across the studies using different measurements of social relationships would allow for comparison of the effects on late-life suicidal ideation that have not been studied before. Therefore, we conducted a meta-analysis on the studies published between January 1, 2000 and November 31, 2016 extracted from 7 medical and social science databases. 31 studies with 83 estimates of Odds Ratios ("ORs") on the associations between social relationships and late-life suicidal ideation were identified to compute effect sizes using a random-effect model. Sensitivity analyses were also performed to evaluate their heterogeneity and bias. Moderator analyses were further conducted to determine moderating factors of the associations. Eventually, across the 31 studies (203,152 participants), the overall random effect size was OR = 1.57(95% CI [1.40, 1.76]), indicating a 57% likelihood increase of suicidal ideation for elderly participants with discordant social relationships. The functional measures (OR = 1.77; 95%CI [1.48, 2.10]) of social relationships, however, were more predictive than structural measures (OR = 1.37; 95%CI [1.25, 1.51]). Among all the measures of social relationships, elderly mistreatment (OR = 2.31; 95%CI [1.81, 2.94]) had the strongest effect size, followed by perceived loneliness (OR = 2.24; 95%CI [1.73, 2.90]) and poorly perceived social support (OR = 1.59; 95% CI [1.37, 1.83]). The associations between social relationships and late-life suicidal ideation were moderated by country income levels, social-cultural context, study types, and various measurements of social relationships. More importantly, our study is the

A genome-wide association study meta-analysis of clinical fracture in 10,012 African American women

Directory of Open Access Journals (Sweden)

Kira C. Taylor

2016-12-01

Full Text Available Background: Osteoporosis is a major public health problem associated with excess disability and mortality. It is estimated that 50–70% of the variation in osteoporotic fracture risk is attributable to genetic factors. The purpose of this hypothesis-generating study was to identify possible genetic determinants of fracture among African American (AA women in a GWAS meta-analysis. Methods: Data on clinical fractures (all fractures except fingers, toes, face, skull or sternum were analyzed among AA female participants in the Women's Health Initiative (WHI (N = 8155, Cardiovascular Health Study (CHS (N = 504, BioVU (N = 704, Health ABC (N = 651, and the Johnston County Osteoarthritis Project (JoCoOA (N = 291. Affymetrix (WHI and Illumina (Health ABC, JoCoOA, BioVU, CHS GWAS panels were used for genotyping, and a 1:1 ratio of YRI:CEU HapMap haplotypes was used as an imputation reference panel. We used Cox proportional hazard models or logistic regression to evaluate the association of ~2.5 million SNPs with fracture risk, adjusting for ancestry, age, and geographic region where applicable. We conducted a fixed-effects, inverse variance-weighted meta-analysis. Genome-wide significance was set at P < 5 × 10−8. Results: One SNP, rs12775980 in an intron of SVIL on chromosome 10p11.2, reached genome-wide significance (P = 4.0 × 10−8. Although this SNP has a low minor allele frequency (0.03, there was no evidence for heterogeneity of effects across the studies (I2 = 0. This locus was not reported in any previous osteoporosis-related GWA studies. We also interrogated previously reported GWA-significant loci associated with fracture or bone mineral density in our data. One locus (SMOC1 generalized, but overall there was not substantial evidence of generalization. Possible reasons for the lack of generalization are discussed. Conclusion: This GWAS meta-analysis of fractures in African American women identified a potentially novel

CD147/EMMPRIN overexpression and prognosis in cancer: A systematic review and meta-analysis

OpenAIRE

Xin, Xiaoyan; Zeng, Xianqin; Gu, Huajian; Li, Min; Tan, Huaming; Jin, Zhishan; Hua, Teng; Shi, Rui; Wang, Hongbo

2016-01-01

CD147/EMMPRIN (extracellular matrix metalloproteinase inducer) plays an important role in tumor progression and a number of studies have suggested that it is an indicator of tumor prognosis. This current meta-analysis systematically reevaluated the predictive potential of CD147/EMMPRIN in various cancers. We searched PubMed and Embase databases to screen the literature. Fixed-effect and random-effect meta-analytical techniques were used to correlate CD147 expression with outcome measures. A t...

Why does self-reported emotional intelligence predict job performance? A meta-analytic investigation of mixed EI.

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Joseph, Dana L; Jin, Jing; Newman, Daniel A; O'Boyle, Ernest H

2015-03-01

Recent empirical reviews have claimed a surprisingly strong relationship between job performance and self-reported emotional intelligence (also commonly called trait EI or mixed EI), suggesting self-reported/mixed EI is one of the best known predictors of job performance (e.g., ρ = .47; Joseph & Newman, 2010b). Results further suggest mixed EI can robustly predict job performance beyond cognitive ability and Big Five personality traits (Joseph & Newman, 2010b; O'Boyle, Humphrey, Pollack, Hawver, & Story, 2011). These criterion-related validity results are problematic, given the paucity of evidence and the questionable construct validity of mixed EI measures themselves. In the current research, we update and reevaluate existing evidence for mixed EI, in light of prior work regarding the content of mixed EI measures. Results of the current meta-analysis demonstrate that (a) the content of mixed EI measures strongly overlaps with a set of well-known psychological constructs (i.e., ability EI, self-efficacy, and self-rated performance, in addition to Conscientiousness, Emotional Stability, Extraversion, and general mental ability; multiple R = .79), (b) an updated estimate of the meta-analytic correlation between mixed EI and supervisor-rated job performance is ρ = .29, and (c) the mixed EI-job performance relationship becomes nil (β = -.02) after controlling for the set of covariates listed above. Findings help to establish the construct validity of mixed EI measures and further support an intuitive theoretical explanation for the uncommonly high association between mixed EI and job performance--mixed EI instruments assess a combination of ability EI and self-perceptions, in addition to personality and cognitive ability. PsycINFO Database Record (c) 2015 APA, all rights reserved.

A study and meta-analysis of lay attributions of cures for overcoming specific psychological problems.

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Furnham, A; Hayward, R

1997-09-01

Lay beliefs about the importance of 24 different contributors to overcoming 4 disorders that constitute primarily cognitive deficits were studied. A meta-analysis of previous programmatic studies in the area was performed so that 22 different psychological problems could be compared. In the present study, 107 participants completed a questionnaire indicating how effective 24 factors were in overcoming 4 specific problems: dyslexia, fear of flying, amnesia, and learning difficulties. Factor analysis revealed almost identical clusters (inner control, social consequences, understanding, receiving help, and fate) for each problem. The perceived relevance of those factors differed significantly between problems. Some individual difference factors (sex and religion) were found to predict certain factor attributions for specific disorders. A meta-analysis of the 5 studies in this series yielded a 6-factor structure comparable to those of the individual studies and provided results indicating the benefits and limitations of this kind of investigation. The clinical relevance of studying attributions for cure is considered.

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

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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.

Endorsement of PRISMA statement and quality of systematic reviews and meta-analyses published in nursing journals: a cross-sectional study.

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Tam, Wilson W S; Lo, Kenneth K H; Khalechelvam, Parames

2017-02-07

Systematic reviews (SRs) often poorly report key information, thereby diminishing their usefulness. Previous studies evaluated published SRs and determined that they failed to meet explicit criteria or characteristics. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was recommended as a reporting guideline for SR and meta-analysis (MA), but previous studies showed that adherence to the statement was not high for SRs published in different medical fields. Thus, the aims of this study are twofold: (1) to investigate the number of nursing journals that have required or recommended the use of the PRISMA statement for reporting SR, and (2) to examine the adherence of SRs and/or meta-analyses to the PRISMA statement published in nursing journals. A cross-sectional study. Nursing journals listed in the ISI journal citation report were divided into 2 groups based on the recommendation of PRISMA statement in their 'Instruction for Authors'. SRs and meta-analyses published in 2014 were searched in 3 databases. 37 SRs and meta-analyses were randomly selected in each group. The adherence of each item to the PRISMA was examined and summarised using descriptive statistics. The quality of the SRs was assessed by Assessing the Methodological Quality of Systematic Reviews. The differences between the 2 groups were compared using the Mann-Whitney U test. Out of 107 nursing journals, 30 (28.0%) recommended or required authors to follow the PRISMA statement when they submit SRs or meta-analyses. The median rates of adherence to the PRISMA statement for reviews published in journals with and without PRISMA endorsement were 64.9% (IQR: 17.6-92.3%) and 73.0% (IQR: 59.5-94.6%), respectively. No significant difference was observed in any of the items between the 2 groups. The median adherence of SRs and meta-analyses in nursing journals to PRISMA is low at 64.9% and 73.0%, respectively. Nonetheless, the adherence level of nursing journals to the

Endorsement of PRISMA statement and quality of systematic reviews and meta-analyses published in nursing journals: a cross-sectional study

Science.gov (United States)

Tam, Wilson W S; Lo, Kenneth K H; Khalechelvam, Parames

2017-01-01

Objective Systematic reviews (SRs) often poorly report key information, thereby diminishing their usefulness. Previous studies evaluated published SRs and determined that they failed to meet explicit criteria or characteristics. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was recommended as a reporting guideline for SR and meta-analysis (MA), but previous studies showed that adherence to the statement was not high for SRs published in different medical fields. Thus, the aims of this study are twofold: (1) to investigate the number of nursing journals that have required or recommended the use of the PRISMA statement for reporting SR, and (2) to examine the adherence of SRs and/or meta-analyses to the PRISMA statement published in nursing journals. Design A cross-sectional study. Methods Nursing journals listed in the ISI journal citation report were divided into 2 groups based on the recommendation of PRISMA statement in their ‘Instruction for Authors’. SRs and meta-analyses published in 2014 were searched in 3 databases. 37 SRs and meta-analyses were randomly selected in each group. The adherence of each item to the PRISMA was examined and summarised using descriptive statistics. The quality of the SRs was assessed by Assessing the Methodological Quality of Systematic Reviews. The differences between the 2 groups were compared using the Mann-Whitney U test. Results Out of 107 nursing journals, 30 (28.0%) recommended or required authors to follow the PRISMA statement when they submit SRs or meta-analyses. The median rates of adherence to the PRISMA statement for reviews published in journals with and without PRISMA endorsement were 64.9% (IQR: 17.6–92.3%) and 73.0% (IQR: 59.5–94.6%), respectively. No significant difference was observed in any of the items between the 2 groups. Conclusions The median adherence of SRs and meta-analyses in nursing journals to PRISMA is low at 64.9% and 73.0%, respectively

MicroRNA meta-signature of oral cancer: evidence from a meta-analysis.

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Zeljic, Katarina; Jovanovic, Ivan; Jovanovic, Jasmina; Magic, Zvonko; Stankovic, Aleksandra; Supic, Gordana

2018-03-01

It was the aim of the study to identify commonly deregulated miRNAs in oral cancer patients by performing a meta-analysis of previously published miRNA expression profiles in cancer and matched normal non-cancerous tissue in such patients. Meta-analysis included seven independent studies analyzed by a vote-counting method followed by bioinformatic enrichment analysis. Amongst seven independent studies included in the meta-analysis, 20 miRNAs were found to be deregulated in oral cancer when compared with non-cancerous tissue. Eleven miRNAs were consistently up-regulated in three or more studies (miR-21-5p, miR-31-5p, miR-135b-5p, miR-31-3p, miR-93-5p, miR-34b-5p, miR-424-5p, miR-18a-5p, miR-455-3p, miR-450a-5p, miR-21-3p), and nine were down-regulated (miR-139-5p, miR-30a-3p, miR-376c-3p, miR-885-5p, miR-375, miR-486-5p, miR-411-5p, miR-133a-3p, miR-30a-5p). The meta-signature of identified miRNAs was functionally characterized by KEGG enrichment analysis. Twenty-four KEGG pathways were significantly enriched, and TGF-beta signaling was the most enriched signaling pathway. The highest number of meta-signature miRNAs was involved in the sphingolipid signaling pathway. Natural killer cell-mediated cytotoxicity was the pathway with most genes regulated by identified miRNAs. The rest of the enriched pathways in our miRNA list describe different malignancies and signaling. The identified miRNA meta-signature might be considered as a potential battery of biomarkers when distinguishing oral cancer tissue from normal, non-cancerous tissue. Further mechanistic studies are warranted in order to confirm and fully elucidate the role of deregulated miRNAs in oral cancer.

Safety at work: a meta-analytic investigation of the link between job demands, job resources, burnout, engagement, and safety outcomes.

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Nahrgang, Jennifer D; Morgeson, Frederick P; Hofmann, David A

2011-01-01

In this article, we develop and meta-analytically test the relationship between job demands and resources and burnout, engagement, and safety outcomes in the workplace. In a meta-analysis of 203 independent samples (N = 186,440), we found support for a health impairment process and for a motivational process as mechanisms through which job demands and resources relate to safety outcomes. In particular, we found that job demands such as risks and hazards and complexity impair employees' health and positively relate to burnout. Likewise, we found support for job resources such as knowledge, autonomy, and a supportive environment motivating employees and positively relating to engagement. Job demands were found to hinder an employee with a negative relationship to engagement, whereas job resources were found to negatively relate to burnout. Finally, we found that burnout was negatively related to working safely but that engagement motivated employees and was positively related to working safely. Across industries, risks and hazards was the most consistent job demand and a supportive environment was the most consistent job resource in terms of explaining variance in burnout, engagement, and safety outcomes. The type of job demand that explained the most variance differed by industry, whereas a supportive environment remained consistent in explaining the most variance in all industries.

Meta-Analysis for Primary and Secondary Data Analysis: The Super-Experiment Metaphor.

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Jackson, Sally

1991-01-01

Considers the relation between meta-analysis statistics and analysis of variance statistics. Discusses advantages and disadvantages as a primary data analysis tool. Argues that the two approaches are partial paraphrases of one another. Advocates an integrative approach that introduces the best of meta-analytic thinking into primary analysis…

Does Parent-Child Interaction Therapy Reduce Future Physical Abuse? A Meta-Analysis

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Kennedy, Stephanie C.; Kim, Johnny S.; Tripodi, Stephen J.; Brown, Samantha M.; Gowdy, Grace

2016-01-01

Objective: To use meta-analytic techniques to evaluating the effectiveness of parent-child interaction therapy (PCIT) at reducing future physical abuse among physically abusive families. Methods: A systematic search identified six eligible studies. Outcomes of interest were physical abuse recurrence, child abuse potential, and parenting stress.…

Global meta-analysis of transcriptomics studies.

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José Caldas

Full Text Available Transcriptomics meta-analysis aims at re-using existing data to derive novel biological hypotheses, and is motivated by the public availability of a large number of independent studies. Current methods are based on breaking down studies into multiple comparisons between phenotypes (e.g. disease vs. healthy, based on the studies' experimental designs, followed by computing the overlap between the resulting differential expression signatures. While useful, in this methodology each study yields multiple independent phenotype comparisons, and connections are established not between studies, but rather between subsets of the studies corresponding to phenotype comparisons. We propose a rank-based statistical meta-analysis framework that establishes global connections between transcriptomics studies without breaking down studies into sets of phenotype comparisons. By using a rank product method, our framework extracts global features from each study, corresponding to genes that are consistently among the most expressed or differentially expressed genes in that study. Those features are then statistically modelled via a term-frequency inverse-document frequency (TF-IDF model, which is then used for connecting studies. Our framework is fast and parameter-free; when applied to large collections of Homo sapiens and Streptococcus pneumoniae transcriptomics studies, it performs better than similarity-based approaches in retrieving related studies, using a Medical Subject Headings gold standard. Finally, we highlight via case studies how the framework can be used to derive novel biological hypotheses regarding related studies and the genes that drive those connections. Our proposed statistical framework shows that it is possible to perform a meta-analysis of transcriptomics studies with arbitrary experimental designs by deriving global expression features rather than decomposing studies into multiple phenotype comparisons.

Empirical Comparison of Publication Bias Tests in Meta-Analysis.

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Lin, Lifeng; Chu, Haitao; Murad, Mohammad Hassan; Hong, Chuan; Qu, Zhiyong; Cole, Stephen R; Chen, Yong

2018-04-16

Decision makers rely on meta-analytic estimates to trade off benefits and harms. Publication bias impairs the validity and generalizability of such estimates. The performance of various statistical tests for publication bias has been largely compared using simulation studies and has not been systematically evaluated in empirical data. This study compares seven commonly used publication bias tests (i.e., Begg's rank test, trim-and-fill, Egger's, Tang's, Macaskill's, Deeks', and Peters' regression tests) based on 28,655 meta-analyses available in the Cochrane Library. Egger's regression test detected publication bias more frequently than other tests (15.7% in meta-analyses of binary outcomes and 13.5% in meta-analyses of non-binary outcomes). The proportion of statistically significant publication bias tests was greater for larger meta-analyses, especially for Begg's rank test and the trim-and-fill method. The agreement among Tang's, Macaskill's, Deeks', and Peters' regression tests for binary outcomes was moderately strong (most κ's were around 0.6). Tang's and Deeks' tests had fairly similar performance (κ > 0.9). The agreement among Begg's rank test, the trim-and-fill method, and Egger's regression test was weak or moderate (κ < 0.5). Given the relatively low agreement between many publication bias tests, meta-analysts should not rely on a single test and may apply multiple tests with various assumptions. Non-statistical approaches to evaluating publication bias (e.g., searching clinical trials registries, records of drug approving agencies, and scientific conference proceedings) remain essential.

The Own-Age Bias in Face Recognition: A Meta-Analytic and Theoretical Review

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Rhodes, Matthew G.; Anastasi, Jeffrey S.

2012-01-01

A large number of studies have examined the finding that recognition memory for faces of one's own age group is often superior to memory for faces of another age group. We examined this "own-age bias" (OAB) in the meta-analyses reported. These data showed that hits were reliably greater for same-age relative to other-age faces (g = 0.23) and that…

A meta-analysis of neuropsychological outcome after mild traumatic brain injury: re-analyses and reconsiderations of Binder et al. (1997), Frencham et al. (2005), and Pertab et al. (2009).

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Rohling, Martin L; Binder, Laurence M; Demakis, George J; Larrabee, Glenn J; Ploetz, Danielle M; Langhinrichsen-Rohling, Jennifer

2011-05-01

The meta-analytic findings of Binder et al. (1997) and Frencham et al. (2005) showed that the neuropsychological effect of mild traumatic brain injury (mTBI) was negligible in adults by 3 months post injury. Pertab et al. (2009) reported that verbal paired associates, coding tasks, and digit span yielded significant differences between mTBI and control groups. We re-analyzed data from the 25 studies used in the prior meta-analyses, correcting statistical and methodological limitations of previous efforts, and analyzed the chronicity data by discrete epochs. Three months post injury the effect size of -0.07 was not statistically different from zero and similar to that which has been found in several other meta-analyses (Belanger et al., 2005; Schretlen & Shapiro, 2003). The effect size 7 days post injury was -0.39. The effect of mTBI immediately post injury was largest on Verbal and Visual Memory domains. However, 3 months post injury all domains improved to show non-significant effect sizes. These findings indicate that mTBI has an initial small effect on neuropsychological functioning that dissipates quickly. The evidence of recovery in the present meta-analysis is consistent with previous conclusions of both Binder et al. and Frencham et al. Our findings may not apply to people with a history of multiple concussions or complicated mTBIs.

Separating method factors and higher order traits of the Big Five: a meta-analytic multitrait-multimethod approach.

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Chang, Luye; Connelly, Brian S; Geeza, Alexis A

2012-02-01

Though most personality researchers now recognize that ratings of the Big Five are not orthogonal, the field has been divided about whether these trait intercorrelations are substantive (i.e., driven by higher order factors) or artifactual (i.e., driven by correlated measurement error). We used a meta-analytic multitrait-multirater study to estimate trait correlations after common method variance was controlled. Our results indicated that common method variance substantially inflates trait correlations, and, once controlled, correlations among the Big Five became relatively modest. We then evaluated whether two different theories of higher order factors could account for the pattern of Big Five trait correlations. Our results did not support Rushton and colleagues' (Rushton & Irwing, 2008; Rushton et al., 2009) proposed general factor of personality, but Digman's (1997) α and β metatraits (relabeled by DeYoung, Peterson, and Higgins (2002) as Stability and Plasticity, respectively) produced viable fit. However, our models showed considerable overlap between Stability and Emotional Stability and between Plasticity and Extraversion, raising the question of whether these metatraits are redundant with their dominant Big Five traits. This pattern of findings was robust when we included only studies whose observers were intimately acquainted with targets. Our results underscore the importance of using a multirater approach to studying personality and the need to separate the causes and outcomes of higher order metatraits from those of the Big Five. We discussed the implications of these findings for the array of research fields in which personality is studied.

Teaching meta-analysis using MetaLight

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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.

Impact of previous open renal surgery on the outcomes of subsequent percutaneous nephrolithotomy: a meta-analysis.

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Hu, Henglong; Lu, Yuchao; Cui, Lei; Zhang, Jiaqiao; Zhao, Zhenyu; Qin, Baolong; Wang, Yufeng; Wang, Qing; Wang, Shaogang

2016-04-28

The aim of this study was to systematically compare the perioperative outcomes of percutaneous nephrolithotomy in patients with or without previous ipsilateral open renal surgery (POS). Systematic searches of the PubMed, Web of Science and Cochrane Library databases were used to identify relevant studies, and, following literature screening and data extraction, a meta-analysis was performed. 17 retrospective cohort studies involving 4833 procedures (4784 patients) were included. No statistically significant differences were observed between patients with or without POS in terms of supracostal access; single/multiple tracts; metal dilator need; time required to access the collecting system; fluoroscopic duration; demand for analgesics; hospital stay; final stone-free rate; and risk of developing certain complications (eg, fever, haemorrhage, haemo/hydro/pneumothorax, blood transfusion, urinary tract infection and sepsis) as well as regarding the risk of total complications. Patients with POS, however, had a greater drop in haemoglobin (weighted mean difference (WMD), 1.78 g/L; 95% CI 1.09 to 2.47; pPOS also had a lower initial stone-free rate (RR, 0.96; 95% CI 0.92 to 0.99; p=0.007) and more secondary treatment (RR, 1.61; 95% CI 1.09 to 2.37; p=0.02). Sensitivity analysis produced comparable results except for differences in operative time and initial stone-free rate, which did, however, prove to be statistically insignificant (p=0.16 and 0.69, respectively). Current evidence suggests that percutaneous nephrolithotomy in patients with POS is associated with a significantly greater drop in haemoglobin, higher risk of requiring angiographic embolisation and auxiliary procedures, potentially longer operative time, and lower initial stone-free rate than percutaneous nephrolithotomy in patients without POS. 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/

Gender Differences among Children with ADHD on Continuous Performance Tests: A Meta-Analytic Review

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Hasson, Ramzi; Fine, Jodene Goldenring

2012-01-01

Objective: Gender differences among children with ADHD are not well understood. The continuous performance test (CPT) is the most frequently used direct measure of inattention and impulsivity. This meta-analysis compared CPT performance between boys and girls with and without ADHD. Method: All peer-reviewed ADHD studies published between 1980 and…

Hypnosis as an Adjunct to Cognitive-Behavioral Psychotherapy for Obesity: A Meta-analytic Reappraisal.

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Allison, David B.; Faith, Myles S.

1996-01-01

A meta-analysis for six weight-loss studies comparing the efficacy of cognitive-behavior therapy (CBT) alone to CBT plus hypnotherapy. Notes that "the addition of hypnosis substantially enhanced treatment outcome." Concludes that the addition of hypnosis to CBT for weight loss results in, at most, a small enhancement of treatment…

Age as a Risk Factor for Burnout Syndrome in Nursing Professionals: A Meta-Analytic Study.

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Gómez-Urquiza, José L; Vargas, Cristina; De la Fuente, Emilia I; Fernández-Castillo, Rafael; Cañadas-De la Fuente, Guillermo A

2017-04-01

Although past research has highlighted the possibility of a direct relationship between the age of nursing professionals and burnout syndrome, results have been far from conclusive. The aim of this study was to conduct a wider analysis of the influence of age on the three dimensions of burnout syndrome (emotional exhaustion, depersonalization, and personal accomplishment) in nurses. We performed a meta-analysis of 51 publications extracted from health sciences and psychology databases that fulfilled the inclusion criteria. There were 47 reports of information on emotional exhaustion in 50 samples, 39 reports on depersonalization for 42 samples, and 31 reports on personal accomplishment in 34 samples. The mean effect sizes indicated that younger age was a significant factor in the emotional exhaustion and depersonalization of nurses, although it was somewhat less influential in the dimension of personal accomplishment. Because of heterogeneity in the effect sizes, moderating variables that might explain the association between age and burnout were also analyzed. Gender, marital status, and study characteristics moderated the relationship between age and burnout and may be crucial for the identification of high-risk groups. More research is needed on other variables for which there were only a small number of studies. Identification of burnout risk factors will facilitate establishment of burnout prevention programs for nurses. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Annual age-grouping and athlete development: a meta-analytical review of relative age effects in sport.

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Cobley, Stephen; Baker, Joseph; Wattie, Nick; McKenna, Jim

2009-01-01

Annual age-grouping is a common organizational strategy in sport. However, such a strategy appears to promote relative age effects (RAEs). RAEs refer both to the immediate participation and long-term attainment constraints in sport, occurring as a result of chronological age and associated physical (e.g. height) differences as well as selection practices in annual age-grouped cohorts. This article represents the first meta-analytical review of RAEs, aimed to collectively determine (i) the overall prevalence and strength of RAEs across and within sports, and (ii) identify moderator variables. A total of 38 studies, spanning 1984-2007, containing 253 independent samples across 14 sports and 16 countries were re-examined and included in a single analysis using odds ratios and random effects procedures for combining study estimates. Overall results identified consistent prevalence of RAEs, but with small effect sizes. Effect size increased linearly with relative age differences. Follow-up analyses identified age category, skill level and sport context as moderators of RAE magnitude. Sports context involving adolescent (aged 15-18 years) males, at the representative (i.e. regional and national) level in highly popular sports appear most at risk to RAE inequalities. Researchers need to understand the mechanisms by which RAEs magnify and subside, as well as confirm whether RAEs exist in female and more culturally diverse contexts. To reduce and eliminate this social inequality from influencing athletes' experiences, especially within developmental periods, direct policy, organizational and practitioner intervention is required.

Meta-analysis, Simpson's paradox, and the number needed to treat

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Deeks Jonathan J

2002-01-01

Full Text Available Abstract Background There is debate concerning methods for calculating numbers needed to treat (NNT from results of systematic reviews. Methods We investigate the susceptibility to bias for alternative methods for calculating NNTs through illustrative examples and mathematical theory. Results Two competing methods have been recommended: one method involves calculating the NNT from meta-analytical estimates, the other by treating the data as if it all arose from a single trial. The 'treat-as-one-trial' method was found to be susceptible to bias when there were imbalances between groups within one or more trials in the meta-analysis (Simpson's paradox. Calculation of NNTs from meta-analytical estimates is not prone to the same bias. The method of calculating the NNT from a meta-analysis depends on the treatment effect used. When relative measures of treatment effect are used the estimates of NNTs can be tailored to the level of baseline risk. Conclusions The treat-as-one-trial method of calculating numbers needed to treat should not be used as it is prone to bias. Analysts should always report the method they use to compute estimates to enable readers to judge whether it is appropriate.

The Role of Sexual Orientation in School-Based Victimization: A Meta-Analysis

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Toomey, Russell B.; Russell, Stephen T.

2016-01-01

School-based victimization is associated with poorer developmental, academic, and health outcomes. This meta-analytic review compared the mean levels of school-based victimization experienced by sexual minority youth to those of heterosexual youth, and examined moderators of this difference. Results from 18 independent studies (N = 56,752…

Konsumsi Alkohol, Obat-obatan Terlarang dan Perilaku Seks Berisiko: Suatu Studi Meta-Analisis

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Wahyu Rahardjo

2013-05-01

Full Text Available Risky sexual behavior has been consi-dered as a widespread social phenomenon recently. Its bad consequences bring us to the fact of the increasing of HIV/AIDS cases in the world. Behaviors like condom inconsis-tency, multiple sex partners and dangerous sexual encounters could be shaped by subs-tance use. Substance use itself is consist of the use of alcohol and drugs like marijuana, cocaine, methamphetamine, ecstasy etc. This meta-analysis consist of 101 studies from 30 articles, involving 30136 participants from heterosexual male and female to bisexual and gay male. The result shows positive and significant correlation between substance use and risky sexual behavior. However, this fin-ding supports previous research’s results and also give further insight for other researchers in order to have more concern on other varia-bles for predicting risky sexual behavior. Keywords: substance use, risky sexual behavior, meta-analysis

Bayesian meta-analysis models for microarray data: a comparative study

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Song Joon J

2007-03-01

Full Text Available Abstract Background With the growing abundance of microarray data, statistical methods are increasingly needed to integrate results across studies. Two common approaches for meta-analysis of microarrays include either combining gene expression measures across studies or combining summaries such as p-values, probabilities or ranks. Here, we compare two Bayesian meta-analysis models that are analogous to these methods. Results Two Bayesian meta-analysis models for microarray data have recently been introduced. The first model combines standardized gene expression measures across studies into an overall mean, accounting for inter-study variability, while the second combines probabilities of differential expression without combining expression values. Both models produce the gene-specific posterior probability of differential expression, which is the basis for inference. Since the standardized expression integration model includes inter-study variability, it may improve accuracy of results versus the probability integration model. However, due to the small number of studies typical in microarray meta-analyses, the variability between studies is challenging to estimate. The probability integration model eliminates the need to model variability between studies, and thus its implementation is more straightforward. We found in simulations of two and five studies that combining probabilities outperformed combining standardized gene expression measures for three comparison values: the percent of true discovered genes in meta-analysis versus individual studies; the percent of true genes omitted in meta-analysis versus separate studies, and the number of true discovered genes for fixed levels of Bayesian false discovery. We identified similar results when pooling two independent studies of Bacillus subtilis. We assumed that each study was produced from the same microarray platform with only two conditions: a treatment and control, and that the data sets

The Neural Correlates of Moral Thinking: A Meta-Analysis

OpenAIRE

Douglas J. Bryant; Wang F; Kelley Deardeuff; Emily Zoccoli; Chang S. Nam

2016-01-01

We conducted a meta-analysis to evaluate current research that aims to map the neural correlates of two typical conditions of moral judgment: right-wrong moral judgments and decision-making in moral dilemmas. Utilizing the activation likelihood estimation (ALE) method, we conducted a meta-analysis using neuroimaging data obtained from twenty-one previous studies that measured responses in one or the other of these conditions. We found that across the studies (n = 400), distinct neural circuit...

Interactions between plant growth and soil nutrient cycling under elevated CO2: a meta-analysis

NARCIS (Netherlands)

Graaff, de M.A.; Groenigen, van K.J.; Six, J.; Hungate, B.; Kessel, van C.

2006-01-01

free air carbon dioxide enrichment (FACE) and open top chamber (OTC) studies are valuable tools for evaluating the impact of elevated atmospheric CO2 on nutrient cycling in terrestrial ecosystems. Using meta-analytic techniques, we summarized the results of 117 studies on plant biomass production,

Analysis and synthesis of bianisotropic metasurfaces by using analytical approach based on equivalent parameters

Science.gov (United States)

Danaeifar, Mohammad; Granpayeh, Nosrat

2018-03-01

An analytical method is presented to analyze and synthesize bianisotropic metasurfaces. The equivalent parameters of metasurfaces in terms of meta-atom properties and other specifications of metasurfaces are derived. These parameters are related to electric, magnetic, and electromagnetic/magnetoelectric dipole moments of the bianisotropic media, and they can simplify the analysis of complicated and multilayer structures. A metasurface of split ring resonators is studied as an example demonstrating the proposed method. The optical properties of the meta-atom are explored, and the calculated polarizabilities are applied to find the reflection coefficient and the equivalent parameters of the metasurface. Finally, a structure consisting of two metasurfaces of the split ring resonators is provided, and the proposed analytical method is applied to derive the reflection coefficient. The validity of this analytical approach is verified by full-wave simulations which demonstrate good accuracy of the equivalent parameter method. This method can be used in the analysis and synthesis of bianisotropic metasurfaces with different materials and in different frequency ranges by considering electric, magnetic, and electromagnetic/magnetoelectric dipole moments.

Sports Participation and Juvenile Delinquency: A Meta-Analytic Review.

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Spruit, Anouk; van Vugt, Eveline; van der Put, Claudia; van der Stouwe, Trudy; Stams, Geert-Jan

2016-04-01

Participation in sports activities is very popular among adolescents, and is frequently encouraged among youth. Many psychosocial health benefits in youth are attributed to sports participation, but to what extent this positive influence holds for juvenile delinquency is still not clear on both the theoretical and empirical level. There is much controversy on whether sports participation should be perceived as a protective or a risk factor for the development of juvenile delinquency. A multilevel meta-analysis of 51 published and unpublished studies, with 48 independent samples containing 431 effect sizes and N = 132,366 adolescents, was conducted to examine the relationship between sports participation and juvenile delinquency and possible moderating factors of this association. The results showed that there is no overall significant association between sports participation and juvenile delinquency, indicating that adolescent athletes are neither more nor less delinquent than non-athletes. Some study, sample and sports characteristics significantly moderated the relationship between sports participation and juvenile delinquency. However, this moderating influence was modest. Implications for theory and practice concerning the use of sports to prevent juvenile delinquency are discussed.

Sex differences in general knowledge: meta-analysis and new data on the contribution of school-related moderators among high-school students.

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Tran, Ulrich S; Hofer, Agnes A; Voracek, Martin

2014-01-01

Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge.

A Comparative Meta-Analysis of 5E and Traditional Approaches in Turkey

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Anil, Özgür; Batdi, Veli

2015-01-01

The aim of this study is to compare the 5E learning model with traditional learning methods in terms of their effect on students' academic achievement, retention and attitude scores. In this context, the meta-analytic method known as the "analysis of analyses" was used and a review undertaken of the studies and theses (N = 14) executed…

The "handwriting brain": a meta-analysis of neuroimaging studies of motor versus orthographic processes.

Science.gov (United States)

Planton, Samuel; Jucla, Mélanie; Roux, Franck-Emmanuel; Démonet, Jean-François

2013-01-01

Handwriting is a modality of language production whose cerebral substrates remain poorly known although the existence of specific regions is postulated. The description of brain damaged patients with agraphia and, more recently, several neuroimaging studies suggest the involvement of different brain regions. However, results vary with the methodological choices made and may not always discriminate between "writing-specific" and motor or linguistic processes shared with other abilities. We used the "Activation Likelihood Estimate" (ALE) meta-analytical method to identify the cerebral network of areas commonly activated during handwriting in 18 neuroimaging studies published in the literature. Included contrasts were also classified according to the control tasks used, whether non-specific motor/output-control or linguistic/input-control. These data were included in two secondary meta-analyses in order to reveal the functional role of the different areas of this network. An extensive, mainly left-hemisphere network of 12 cortical and sub-cortical areas was obtained; three of which were considered as primarily writing-specific (left superior frontal sulcus/middle frontal gyrus area, left intraparietal sulcus/superior parietal area, right cerebellum) while others related rather to non-specific motor (primary motor and sensorimotor cortex, supplementary motor area, thalamus and putamen) or linguistic processes (ventral premotor cortex, posterior/inferior temporal cortex). This meta-analysis provides a description of the cerebral network of handwriting as revealed by various types of neuroimaging experiments and confirms the crucial involvement of the left frontal and superior parietal regions. These findings provide new insights into cognitive processes involved in handwriting and their cerebral substrates. Copyright © 2013 Elsevier Ltd. All rights reserved.

The revelation effect: A meta-analytic test of hypotheses.

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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.

The effectiveness of working memory training with individuals with intellectual disabilities – a meta-analytic review

Directory of Open Access Journals (Sweden)

Henrik eDanielsson

2015-08-01

Full Text Available Working memory training has been increasingly popular in the last year. Previous studies has shown that children with intellectual disabilities have low working memory capacity and therefore have a great potential for improvement by this type of intervention. The aim of this study was to investigate the effect of working memory and cognitive training for children with intellectual disabilities. The effects reported in previous studies have varied and therefore meta-analysis of articles in the major databases was conducted. Inclusion criteria included to have a pretest-posttest design with a training group and a control group and to have measures of working memory or short-term memory. Ten studies with 28 comparisons were included. The results reveal a significant overall pretest-posttest small effect size for of working memory training for children with intellectual disabilities compared to controls. A mixed working memory approach, considering both verbal and visuo-spatial components and working mainly on strategies, was the only significantly effective training type with a medium effect size. The most commonly reported training type with 60 percent of the included comparisons, visuo-spatial working memory training, had a non-significant effect size that was close to zero. We conclude that even if there is an overall effect of working memory training, a mixed working memory approach appears to cause this effect. Given the few studies included and the different characteristics of the included studies, interpretations should be done with caution. However, different types of interventions appear to have different effects. Even if the results were promising, more studies are needed to better understand how to design an effective working memory intervention for this group and to understand if, and how, these short-term effects remains over time and transfer to everyday activities.

Testing the Strength of the Iron Cage: A Meta-Analysis of Neo-Institutional Theory

NARCIS (Netherlands)

P.P.M.A.R. Heugens (Pursey); M.W. Lander (Michel)

2007-01-01

textabstractIn this study, we use meta-analytical techniques to quantitatively synthesize and evaluate the sizeable body of empirical work that has been conducted under the banner of neo-institutional theory. We find strong support for the influence of mimetic pressures on organizational

Psychosocial Factors and Community College Student Success: A Meta-Analytic Investigation

Science.gov (United States)

Fong, Carlton J.; Davis, Coreen W.; Kim, Yughi; Kim, Young Won; Marriott, Lauren; Kim, SooYeon

2017-01-01

This meta-analysis examined the relationship between psychosocial factors and community college student success. Informed by college persistence models and motivational theory, we statistically integrated past research on five psychosocial categories (motivation, self-perceptions, attributions, self-regulation, and anxiety), examining their…

An Introduction to MAMA (Meta-Analysis of MicroArray data) System.

Science.gov (United States)

Zhang, Zhe; Fenstermacher, David

2005-01-01

Analyzing microarray data across multiple experiments has been proven advantageous. To support this kind of analysis, we are developing a software system called MAMA (Meta-Analysis of MicroArray data). MAMA utilizes a client-server architecture with a relational database on the server-side for the storage of microarray datasets collected from various resources. The client-side is an application running on the end user's computer that allows the user to manipulate microarray data and analytical results locally. MAMA implementation will integrate several analytical methods, including meta-analysis within an open-source framework offering other developers the flexibility to plug in additional statistical algorithms.

Anxiety disorders in children and adolescents with autistic spectrum disorders: a meta-analysis

NARCIS (Netherlands)

van Steensel, F.J.A.; Bögels, S.M.; Perrin, S.

2011-01-01

There is considerable evidence that children and adolescents with autistic spectrum disorders (ASD) are at increased risk of anxiety and anxiety disorders. However, it is less clear which of the specific DSM-IV anxiety disorders occur most in this population. The present study used meta-analytic

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.

How acute total sleep loss affects the attending brain: a meta-analysis of neuroimaging studies.

Science.gov (United States)

Ma, Ning; Dinges, David F; Basner, Mathias; Rao, Hengyi

2015-02-01

Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. © 2015 Associated Professional Sleep Societies, LLC.

Meta-analyzing dependent correlations: an SPSS macro and an R script.

Science.gov (United States)

Cheung, Shu Fai; Chan, Darius K-S

2014-06-01

The presence of dependent correlation is a common problem in meta-analysis. Cheung and Chan (2004, 2008) have shown that samplewise-adjusted procedures perform better than the more commonly adopted simple within-sample mean procedures. However, samplewise-adjusted procedures have rarely been applied in meta-analytic reviews, probably due to the lack of suitable ready-to-use programs. In this article, we compare the samplewise-adjusted procedures with existing procedures to handle dependent effect sizes, and present the samplewise-adjusted procedures in a way that will make them more accessible to researchers conducting meta-analysis. We also introduce two tools, an SPSS macro and an R script, that researchers can apply to their meta-analyses; these tools are compatible with existing meta-analysis software packages.

Methodological quality of meta-analyses on treatments for chronic obstructive pulmonary disease: a cross-sectional study using the AMSTAR (Assessing the Methodological Quality of Systematic Reviews) tool.

Science.gov (United States)

Ho, Robin S T; Wu, Xinyin; Yuan, Jinqiu; Liu, Siya; Lai, Xin; Wong, Samuel Y S; Chung, Vincent C H

2015-01-08

Meta-analysis (MA) of randomised trials is considered to be one of the best approaches for summarising high-quality evidence on the efficacy and safety of treatments. However, methodological flaws in MAs can reduce the validity of conclusions, subsequently impairing the quality of decision making. To assess the methodological quality of MAs on COPD treatments. A cross-sectional study on MAs of COPD trials. MAs published during 2000-2013 were sampled from the Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effect. Methodological quality was assessed using the validated AMSTAR (Assessing the Methodological Quality of Systematic Reviews) tool. Seventy-nine MAs were sampled. Only 18% considered the scientific quality of primary studies when formulating conclusions and 49% used appropriate meta-analytic methods to combine findings. The problems were particularly acute among MAs on pharmacological treatments. In 48% of MAs the authors did not report conflict of interest. Fifty-eight percent reported harmful effects of treatment. Publication bias was not assessed in 65% of MAs, and only 10% had searched non-English databases. The methodological quality of the included MAs was disappointing. Consideration of scientific quality when formulating conclusions should be made explicit. Future MAs should improve on reporting conflict of interest and harm, assessment of publication bias, prevention of language bias and use of appropriate meta-analytic methods.

Limitations and risks of meta-analyses of longevity studies

DEFF Research Database (Denmark)

Sebastiani, Paola; Bae, Harold; Gurinovich, Anastasia

2017-01-01

Searching for genetic determinants of human longevity has been challenged by the rarity of data sets with large numbers of individuals who have reached extreme old age, inconsistent definitions of the phenotype, and the difficulty of defining appropriate controls. Meta-analysis - a statistical...... method to summarize results from different studies - has become a common tool in genetic epidemiology to accrue large sample sizes for powerful genetic association studies. In conducting a meta-analysis of studies of human longevity however, particular attention must be made to the definition of cases...... and controls (including their health status) and on the effect of possible confounders such as sex and ethnicity upon the genetic effect to be estimated. We will show examples of how a meta-analysis can inflate the false negative rates of genetic association studies or it can bias estimates of the association...

Images of Stakeholder Groups Based on Their Environmental Sustainability Linked CSR Projects: A Meta-Analytic Review of Korean Sport Literature

Directory of Open Access Journals (Sweden)

Hyun-Duck Kim

2017-09-01

Full Text Available Achieving sustainability in sports events requires effective management, political leadership, and ensuring that all stakeholders adhere to a sustainable philosophy. In order to stage a mega-event, tremendous infrastructure and construction are required with significant consumption of private and public resources. Multiple stakeholder groups are recognized as key entities responsible for an efficient trigger of a mega-event. The aim of this study is to conduct a systematic review of Korean sport literature with regard to CSR practices (ES-linked of different stakeholder groups and examine through a meta-analytic methodology their impact on the “images” of these groups. The CMA program was utilized as the main analysis tool to calculate the effect sizes from the selected empirical studies. The results indicated that CSR performance of governmental organizations had the highest effect size level on their own image (brand identity as perceived by visitors and participants. Among the stakeholder groups, effect size levels of their CSR performances were followed by those of corporate sponsors and professional teams. It was found that stakeholder groups are pressured to maintain a balance between financial performance, consumer well-being, and brand identity to bring in external investment.

Does the Theory of Planned Behaviour Explain Condom Use Behaviour Among Men Who have Sex with Men? A Meta-analytic Review of the Literature.

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Andrew, Benjamin J; Mullan, Barbara A; de Wit, John B F; Monds, Lauren A; Todd, Jemma; Kothe, Emily J

2016-12-01

The aim of this meta-analysis was to explore whether the constructs in the theory of planned behaviour (TPB; i.e., attitude, subjective norm, perceived behavioural control, intention) explain condom use behaviour among men who have sex with men (MSM). Electronic databases were searched for studies that measured TPB variables and MSM condom use. Correlations were meta-analysed using a random effects model and path analyses. Moderation analyses were conducted for the time frame of the behavioural measure used (retrospective versus prospective). Attitude, subjective norm and perceived behavioural control accounted for 24.0 % of the variance in condom use intention and were all significant correlates. Intention and PBC accounted for 12.4 % of the variance in condom use behaviour. However, after taking intention into account, PBC was no longer significantly associated with condom use. The strength of construct relationships did not differ between retrospective and prospective behavioural assessments. The medium to large effect sizes of the relationships between the constructs in the TPB, which are consistent with previous meta-analyses with different behaviours or target groups, suggest that the TPB is also a useful model for explaining condom use behaviour among MSM. However, the research in this area is rather small, and greater clarity over moderating factors can only be achieved when the literature expands.

Fish intake and ovarian cancer risk: a meta-analysis of 15 case-control and cohort studies.

Directory of Open Access Journals (Sweden)

Pei-yue Jiang

Full Text Available BACKGROUND: Previous epidemiological studies have shown that fish consumption may modify the risk of ovarian cancer. However, these studies yielded controversial results. The present meta-analysis was undertaken to evaluate the relationship between fish intake and ovarian cancer risk. METHODS: A literature search was carried out using Pubmed, Embase, and Cochrane Library Central database for all relevant studies up to August 2013. We pooled the relative risks (RR from individual studies using fixed-effect or random-effect model, and carried out heterogeneity and publication bias analyses. RESULTS: A total of 15 (ten case-control, and five cohort studies were included in the present meta-analysis, representing data for 889,033 female subjects and 6,087 ovarian cancer cases. We found that total fish intake was not significantly associated with the risk of ovarian cancer among cohort studies (RR = 1.04 95% CI [0.89, 1.22] as well as case-control studies (RR = 0.90, 95% CI [0.73,1.12]. There was no evidence of publication bias as suggested by Begg's test (P = 0.55 and Egger's test(P = 0.29. CONCLUSIONS: The present meta-analysis showed that total fish consumption was not significantly associated with the risk of ovarian cancer. Further analysis on different fish species and food preparation methods should be conducted in future studies.

Caffeine ingestion enhances Wingate performance: a meta-analysis.

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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.

A meta-analytic study of the factors driving the purchase of organic food.

Science.gov (United States)

Massey, Maria; O'Cass, Aron; Otahal, Petr

2018-06-01

Interest in the consumption of organic food has steadily risen over the past two decades. Yet after considerable research addressing a range of issues related to organic food consumption no research systematically examines which factors explain consumers' perceptions and purchase of organics. Through a meta-analysis we examine factors underpinning the purchase of organic food using a sample of 124,353 consumers reported in 150 manuscripts over the period from 1991 to 2016. The results demonstrate that credence attributes of organic food are valued more than search and experience attributes. This shows that the market is guided by the perceived benefits of organic over conventionally grown food. These findings do not diminish the importance of search and experience attributes, but suggest that credence attributes have a prominent role in consumer organic food purchases. From the perspective of organic producers and sellers an understanding of consumer perceptions, set within search, experience and credence attributes, has the potential to offer a unique selling proposition and point of differentiation in the market. Copyright © 2018 Elsevier Ltd. All rights reserved.

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.

Breast Density and Risk of Breast Cancer in Asian Women: A Meta-analysis of Observational Studies.

Science.gov (United States)

Bae, Jong-Myon; Kim, Eun Hee

2016-11-01

The established theory that breast density is an independent predictor of breast cancer risk is based on studies targeting white women in the West. More Asian women than Western women have dense breasts, but the incidence of breast cancer is lower among Asian women. This meta-analysis investigated the association between breast density in mammography and breast cancer risk in Asian women. PubMed and Scopus were searched, and the final date of publication was set as December 31, 2015. The effect size in each article was calculated using the interval-collapse method. Summary effect sizes (sESs) and 95% confidence intervals (CIs) were calculated by conducting a meta-analysis applying a random effect model. To investigate the dose-response relationship, random effect dose-response meta-regression (RE-DRMR) was conducted. Six analytical epidemiology studies in total were selected, including one cohort study and five case-control studies. A total of 17 datasets were constructed by type of breast density index and menopausal status. In analyzing the subgroups of premenopausal vs. postmenopausal women, the percent density (PD) index was confirmed to be associated with a significantly elevated risk for breast cancer (sES, 2.21; 95% CI, 1.52 to 3.21; I 2 =50.0%). The RE-DRMR results showed that the risk of breast cancer increased 1.73 times for each 25% increase in PD in postmenopausal women (95% CI, 1.20 to 2.47). In Asian women, breast cancer risk increased with breast density measured using the PD index, regardless of menopausal status. We propose the further development of a breast cancer risk prediction model based on the application of PD in Asian women.

Pet exposure and risk of atopic dermatitis at the pediatric age: a meta-analysis of birth cohort studies.

Science.gov (United States)

Pelucchi, Claudio; Galeone, Carlotta; Bach, Jean-François; La Vecchia, Carlo; Chatenoud, Liliane

2013-09-01

Findings on pet exposure and the risk of atopic dermatitis (AD) in children are inconsistent. With the aim to summarize the results of exposure to different pets on AD, we undertook a meta-analysis of epidemiologic studies on this issue. In August 2012, we conducted a systematic literature search in Medline and Embase. We included analytic studies considering exposure to dogs, cats, other pets, or pets overall during pregnancy, infancy, and/or childhood, with AD assessment performed during infancy or childhood. We calculated summary relative risks and 95% CIs using both fixed- and random-effects models. We computed summary estimates across selected subgroups. Twenty-six publications from 21 birth cohort studies were used in the meta-analyses. The pooled relative risks of AD for exposure versus no exposure were 0.72 (95% CI, 0.61-0.85; I(2) = 46%; results based on 15 studies) for exposure to dogs, 0.94 (95% CI, 0.76-1.16; I(2) = 54%; results based on 13 studies) for exposure to cats, and 0.75 (95% CI, 0.67-0.85; I(2) = 54%; results based on 11 studies) for exposure to pets overall. No heterogeneity emerged across the subgroups examined, except for geographic area. This meta-analysis reported a favorable effect of exposure to dogs and pets on the risk of AD in infants or children, whereas no association emerged with exposure to cats. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

The effect of market orientation and its components on innovation consequences : A meta-analysis

NARCIS (Netherlands)

Grinstein, A.

While there is a rich body of research on market orientation's effect on business performance, much little attention has been given to its effect on innovation consequences. This is the first meta-analytic effort to study the independent effects of market orientation components (customer

Personality and team performance: a meta analysis

NARCIS (Netherlands)

Peeters, Miranda A.G.; van Tuijl, Harrie F.J.M.; Rutte, Christel G.; Reymen, Isabelle

2006-01-01

Using a meta-analytical procedure, the relationship between team composition in terms of the Big-Five personality traits (trait elevation and variability) and team performance were researched. The number of teams upon which analyses were performed ranged from 106 to 527. For the total sample,

Sex differences in nicotine intravenous self-administration: A meta-analytic review.

Science.gov (United States)

Flores, Rodolfo J; Uribe, Kevin P; Swalve, Natashia; O'Dell, Laura E

2017-11-21

This report reflects a meta-analysis that systematically reviewed the literature on intravenous self-administration (IVSA) of nicotine in female and male rats. The goal was to determine if sex differences in nicotine IVSA exist, estimate the magnitude of the effect, and identify potential moderators of the relationship between sex differences and nicotine consumption. Extensive search procedures identified 20 studies that met the inclusion criteria of employing both female and male rats in nicotine IVSA procedures. The meta-analysis was conducted on effect size values that were calculated from mean total intake or nicotine deliveries using the Hedges' unbiased g u statistic. A random effects analysis revealed that overall females self-administered more nicotine than males (weighted g u =0.18, 95% CI [0.003, 0.34]). Subsequent moderator variable analyses revealed that certain procedural conditions influenced the magnitude of sex differences in nicotine IVSA. Specifically, higher reinforcement requirements (>FR1) and extended-access sessions (23h) were associated with greater nicotine IVSA in females versus males. Females also displayed higher nicotine intake than males when the experiment included a light cue that signaled nicotine delivery. Sex differences were not influenced by the diurnal phase of testing, dose of nicotine, or prior operant training. Overall, the results revealed that female rats display higher levels of nicotine IVSA than males, suggesting that the strong reinforcing effects of nicotine promote tobacco use in women. Copyright © 2017 Elsevier Inc. All rights reserved.

Parents’ experiences of neonatal transfer. A meta-study of qualitative research 2000-2017

DEFF Research Database (Denmark)

Aagaard, Hanne; Hall, Elisabeth; Ludvigsen, Mette Spliid

2018-01-01

Transfers of critically ill neonates are frequent phenomena. Even though parents’ par- ticipation is regarded as crucial in neonatal care, a transfer often means that parents and neonates are separated. A systematic review of the parents’ experiences of neo- natal transfer is lacking. This paper ...... identified ‘wavering and wandering’ as a metaphoric representation of the parents’ experiences. The findings add knowledge about meta- study as an approach for com- prehensive qualitative research and point at the value of meta- theory and meta- method analyses....... describes a meta- study addressing qualitative re- search about parents’ experiences of neonatal transfer. Through deconstruction and reflections of theories, methods, and empirical data, the aim was to achieve a deeper understanding of theoretical, empirical, contextual, historical, and methodological is......- sues of qualitative studies concerning parents’ experiences of neonatal transfer over the course of this meta- study (2000–2017). Meta- theory and meta- method analyses showed that caring, transition, and family- centered care were main theoretical frames applied and that interviewing with a small...

A Meta-Analysis of Behavioral Parent Training for Children with Attention Deficit Hyperactivity Disorder

Science.gov (United States)

Lee, Pei-chin; Niew, Wern-ing; Yang, Hao-jan; Chen, Vincent Chin-hung; Lin, Keh-chung

2012-01-01

This meta-analysis examined the effect of behavioral parent training on child and parental outcomes for children with attention deficit hyperactivity disorder. Meta-analytic procedures were used to estimate the effect of behavioral parent training on children with attention deficit hyperactivity disorder. Variables moderating the intervention…

Using beta coefficients to impute missing correlations in meta-analysis research: Reasons for caution.

Science.gov (United States)

Roth, Philip L; Le, Huy; Oh, In-Sue; Van Iddekinge, Chad H; Bobko, Philip

2018-06-01

Meta-analysis has become a well-accepted method for synthesizing empirical research about a given phenomenon. Many meta-analyses focus on synthesizing correlations across primary studies, but some primary studies do not report correlations. Peterson and Brown (2005) suggested that researchers could use standardized regression weights (i.e., beta coefficients) to impute missing correlations. Indeed, their beta estimation procedures (BEPs) have been used in meta-analyses in a wide variety of fields. In this study, the authors evaluated the accuracy of BEPs in meta-analysis. We first examined how use of BEPs might affect results from a published meta-analysis. We then developed a series of Monte Carlo simulations that systematically compared the use of existing correlations (that were not missing) to data sets that incorporated BEPs (that impute missing correlations from corresponding beta coefficients). These simulations estimated ρ̄ (mean population correlation) and SDρ (true standard deviation) across a variety of meta-analytic conditions. Results from both the existing meta-analysis and the Monte Carlo simulations revealed that BEPs were associated with potentially large biases when estimating ρ̄ and even larger biases when estimating SDρ. Using only existing correlations often substantially outperformed use of BEPs and virtually never performed worse than BEPs. Overall, the authors urge a return to the standard practice of using only existing correlations in meta-analysis. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Is excess mortality higher in depressed men than in depressed women? A meta-analytic comparison

NARCIS (Netherlands)

Cuijpers, P.; Vogelzangs, N.; Twisk, J.; Kleiboer, A.M.; Li, J.; Penninx, B.W.

2014-01-01

Background It is not well-established whether excess mortality associated with depression is higher in men than in women. Methods We conducted a meta-analysis of prospective studies in which depression was measured at baseline, where mortality rates were reported at follow-up, and in which separate

Keterlibatan Orangtua dalam Pendidikan dan Komitmen Siswa terhadap Sekolah: Studi Meta-analisis

Directory of Open Access Journals (Sweden)

Titik Kristiyani

2016-03-01

Full Text Available Many studies of parental involvement in education have been conducted, which one of the purposed was to found the effect of parental involevement in education to student engagement in school, but the studies showed varied and conflicting result. This study is a meta analysis of correlation between parental involvement in education and student engagament in school, that want to make synthesis between that varied and conflicting result in the previous studies. The parental involvement in this study consist of all of parental behavior that showed involvement in teenager educational problem, both in the school and home area. There were 35 studies from 15 articles. Result showed that there was positive correlation between parental involvement in education and teenager student engagement.

Differences in the Theory of Mind profiles of patients with anorexia nervosa and individuals on the autism spectrum: A meta-analytic review.

Science.gov (United States)

Leppanen, Jenni; Sedgewick, Felicity; Treasure, Janet; Tchanturia, Kate

2018-07-01

This meta-analytic review examines the theory of mind profiles in both patients with anorexia nervosa (AN) and autistic individuals. The studies examining theory of mind were divided into the following categories: emotional theory of mind, understanding simple social situations, understanding complex social interactions, and implicit social attribution. All included studies investigated differences between healthy control (HCs) individuals and people with AN or autistic people. Differences in theory of mind profile between people with AN and autistic people were explored by conducting moderator analyses. People with AN and autistic people showed a similar theory of mind profile, but autistic individuals showed greater difficulties, particularly in emotional theory of mind. Although both people with AN and autistic people have significant difficulties in all aspects of theory of mind relative to the HCs, some differences in the underlying profile may be present. However, due to relative paucity of theory of mind research among people with AN, further research is still needed before firm conclusion can be drawn. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

Parents' experiences of neonatal transfer. A meta-study of qualitative research 2000-2017.

Science.gov (United States)

Aagaard, Hanne; Hall, Elisabeth O C; Ludvigsen, Mette S; Uhrenfeldt, Lisbeth; Fegran, Liv

2018-02-15

Transfers of critically ill neonates are frequent phenomena. Even though parents' participation is regarded as crucial in neonatal care, a transfer often means that parents and neonates are separated. A systematic review of the parents' experiences of neonatal transfer is lacking. This paper describes a meta-study addressing qualitative research about parents' experiences of neonatal transfer. Through deconstruction and reflections of theories, methods, and empirical data, the aim was to achieve a deeper understanding of theoretical, empirical, contextual, historical, and methodological issues of qualitative studies concerning parents' experiences of neonatal transfer over the course of this meta-study (2000-2017). Meta-theory and meta-method analyses showed that caring, transition, and family-centered care were main theoretical frames applied and that interviewing with a small number of participants was the preferred data collection method. The meta-data-analysis showed that transfer was a scary, unfamiliar, and threatening experience for the parents; they were losing familiar context, were separated from their neonate, and could feel their parenthood disrupted. We identified 'wavering and wandering' as a metaphoric representation of the parents' experiences. The findings add knowledge about meta-study as an approach for comprehensive qualitative research and point at the value of meta-theory and meta-method analyses. © 2018 John Wiley & Sons Ltd.

Distinguishing between vascular dementia and Alzheimer's disease by means of the WAIS : A meta-analysis

NARCIS (Netherlands)

Scherder, Erik J. A.; Oosterman, J

2006-01-01

This study was intended to, meta-analytically, review whether the subtests of the Wechsler Adult Intelligence Scale are useful in differentiating between vascular dementia and Alzheimer's disease. We expected the Alzheimer's disease group to outperform the vascular dementia group on those subtests

Distinguishing between vascular dementia and Alzheimer's disease by means of the WAIS: A meta-analysis

NARCIS (Netherlands)

Scherder, E.J A; Oosterman, J

2006-01-01

This study was intended to, meta-analytically, review whether the subtests of the Wechsler Adult Intelligence Scale are useful in differentiating between vascular dementia and Alzheimer's disease. We expected the Alzheimer's disease group to outperform the vascular dementia group on those subtests

Distinguishing between vascular dementia and alzheimer's disease by means of the WAIS: a meta-analysis.

NARCIS (Netherlands)

Oosterman, J.M.; Scherder, E.J.A.

2006-01-01

This study was intended to, meta-analytically, review whether the subtests of the Wechsler Adult Intelligence Scale are useful in differentiating between vascular dementia and Alzheimer's disease. We expected the Alzheimer's disease group to outperform the vascular dementia group on those subtests

Causes and consequences of collective turnover: a meta-analytic review.

Science.gov (United States)

Heavey, Angela L; Holwerda, Jacob A; Hausknecht, John P

2013-05-01

Given growing interest in collective turnover (i.e., employee turnover at unit and organizational levels), the authors propose an organizing framework for its antecedents and consequences and test it using meta-analysis. Based on analysis of 694 effect sizes drawn from 82 studies, results generally support expected relationships across the 6 categories of collective turnover antecedents, with somewhat stronger and more consistent results for 2 categories: human resource management inducements/investments and job embeddedness signals. Turnover was negatively related to numerous performance outcomes, more strongly so for proximal rather than distal outcomes. Several theoretically grounded moderators help to explain average effect-size heterogeneity for both antecedents and consequences of turnover. Relationships generally did not vary according to turnover type (e.g., total or voluntary), although the relative absence of collective-level involuntary turnover studies is noted and remains an important avenue for future research. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Potential protective effect of lactation against incidence of type 2 diabetes mellitus in women with previous gestational diabetes mellitus: A systematic review and meta-analysis.

Science.gov (United States)

Tanase-Nakao, Kanako; Arata, Naoko; Kawasaki, Maki; Yasuhi, Ichiro; Sone, Hirohito; Mori, Rintaro; Ota, Erika

2017-05-01

Lactation may protect women with previous gestational diabetes mellitus (GDM) from developing type 2 diabetes mellitus, but the results of existing studies are inconsistent, ranging from null to beneficial. We aimed to conduct a systematic review to gather available evidence. Databases MEDLINE, CINAHL, PubMed, and EMBASE were searched on December 15, 2015, without restriction of language or publication year. A manual search was also conducted. We included observational studies (cross-sectional, case-control, and cohort study) with information on lactation and type 2 diabetes mellitus incidence among women with previous GDM. We excluded case studies without control data. Data synthesis was conducted by random-effect meta-analysis. Fourteen reports of 9 studies were included. Overall risk of bias using RoBANS ranged from low to unclear. Longer lactation for more than 4 to 12 weeks postpartum had risk reduction of type 2 diabetes mellitus compared with shorter lactation (OR 0.77, 95% CI 0.01-55.86; OR 0.56, 95% CI 0.35-0.89; OR 0.22, 95% CI 0.13-0.36; type 2 diabetes mellitus evaluation time 5 y, respectively). Exclusive lactation for more than 6 to 9 weeks postpartum also had lower risk of type 2 diabetes mellitus compared with exclusive formula (OR 0.42, 95% CI 0.22-0.81). The findings support the evidence that longer and exclusive lactation may be beneficial for type 2 diabetes mellitus prevention in women with previous GDM. However, the evidence relies only on observational studies. Therefore, further studies are required to address the true causal effect. © 2017 The Authors. Diabetes/Metabolism Research and Reviews Published by John Wiley & Sons Ltd.

Meta-analytic approaches to determine gender differences in the age-incidence characteristics of schizophrenia and related psychoses.

Science.gov (United States)

Jackson, Dan; Kirkbride, James; Croudace, Tim; Morgan, Craig; Boydell, Jane; Errazuriz, Antonia; Murray, Robin M; Jones, Peter B

2013-03-01

A recent systematic review and meta-analysis of the incidence and prevalence of schizophrenia and other psychoses in England investigated the variation in the rates of psychotic disorders. However, some of the questions of interest, and the data collected to answer these, could not be adequately addressed using established meta-analysis techniques. We developed a novel statistical method, which makes combined use of fractional polynomials and meta-regression. This was used to quantify the evidence of gender differences and a secondary peak onset in women, where the outcome of interest is the incidence of schizophrenia. Statistically significant and epidemiologically important effects were obtained using our methods. Our analysis is based on data from four studies that provide 50 incidence rates, stratified by age and gender. We describe several variations of our method, in particular those that might be used where more data is available, and provide guidance for assessing the model fit. Copyright © 2013 John Wiley & Sons, Ltd.

Using meta-differential evolution to enhance a calculation of a continuous blood glucose level.

Science.gov (United States)

Koutny, Tomas

2016-09-01

We developed a new model of glucose dynamics. The model calculates blood glucose level as a function of transcapillary glucose transport. In previous studies, we validated the model with animal experiments. We used analytical method to determine model parameters. In this study, we validate the model with subjects with type 1 diabetes. In addition, we combine the analytic method with meta-differential evolution. To validate the model with human patients, we obtained a data set of type 1 diabetes study that was coordinated by Jaeb Center for Health Research. We calculated a continuous blood glucose level from continuously measured interstitial fluid glucose level. We used 6 different scenarios to ensure robust validation of the calculation. Over 96% of calculated blood glucose levels fit A+B zones of the Clarke Error Grid. No data set required any correction of model parameters during the time course of measuring. We successfully verified the possibility of calculating a continuous blood glucose level of subjects with type 1 diabetes. This study signals a successful transition of our research from an animal experiment to a human patient. Researchers can test our model with their data on-line at https://diabetes.zcu.cz. Copyright © 2016 The Author. Published by Elsevier Ireland Ltd.. All rights reserved.

A Meta-Analysis of Working Memory Impairments in Children with Attention-Deficit/hyperactivity Disorder.

Science.gov (United States)

Martinussen, Rhonda; Hayden, Jill; Hogg-Johnson, Sheilah; Tannock, Rosemary

2005-01-01

Objective: To determine the empirical evidence for deficits in working memory (WM) processes in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). Method: Exploratory meta-analytic procedures were used to investigate whether children with ADHD exhibit WM impairments. Twenty-six empirical research studies published from…

Relationships between social support and student burnout: A meta-analytic approach.

Science.gov (United States)

Kim, Boram; Jee, Sooin; Lee, Joungwha; An, Sunghee; Lee, Sang Min

2018-02-01

This study is a meta-analysis of 19 relevant studies, with 95,434 participants, investigating the relationships between various types of social support and 3 dimensions of student burnout. The overall results indicate that social support is negatively correlated with student burnout. Specifically, school or teacher supports have the strongest negative relationship to student burnout. Social supports from parents and from peers also have a significant negative relationship with student burnout. Among the 3 dimensions of student burnout, inefficacy was more strongly related to social support than emotional exhaustion or cynicism. The results of a moderation analysis suggest that the type of schools (secondary school and postsecondary school) affected the relationships between the overall social support and student burnout. We discuss the implications to ameliorate student burnout. Copyright © 2017 John Wiley & Sons, Ltd.

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

Advances in meta-analysis: examples from internal medicine to neurology.

Science.gov (United States)

Copetti, Massimiliano; Fontana, Andrea; Graziano, Giusi; Veneziani, Federica; Siena, Federica; Scardapane, Marco; Lucisano, Giuseppe; Pellegrini, Fabio

2014-01-01

We review the state of the art in meta-analysis and data pooling following the evolution of the statistical models employed. Starting from a classic definition of meta-analysis of published data, a set of apparent antinomies which characterized the development of the meta-analytic tools are reconciled in dichotomies where the second term represents a possible generalization of the first one. Particular attention is given to the generalized linear mixed models as an overall framework for meta-analysis. Bayesian meta-analysis is discussed as a further possibility of generalization for sensitivity analysis and the use of priors as a data augmentation approach. We provide relevant examples to underline how the need for adequate methods to solve practical issues in specific areas of research have guided the development of advanced methods in meta-analysis. We show how all the advances in meta-analysis naturally merge into the unified framework of generalized linear mixed models and reconcile apparently conflicting approaches. All these complex models can be easily implemented with the standard commercial software available. © 2013 S. Karger AG, Basel.

Effects of aerobic exercise, diet, or both on lipids and lipoproteins in adults: a meta-analysis

Science.gov (United States)

BACKGROUND: Studies addressing the effects of aerobic exercise (E), diet (D), or both (ED) on lipids and lipoproteins have led to conflicting results. OBJECTIVE: Determine the effects of E, D, and ED on lipids and lipoproteins. METHODS: Using the aggregate data meta-analytic approach, studies were ...

Neural correlates of interference resolution in the multi-source interference task: a meta-analysis of functional neuroimaging studies.

Science.gov (United States)

Deng, Yuqin; Wang, Xiaochun; Wang, Yan; Zhou, Chenglin

2018-04-10

Interference resolution refers to cognitive control processes enabling one to focus on task-related information while filtering out unrelated information. But the exact neural areas, which underlie a specific cognitive task on interference resolution, are still equivocal. The multi-source interference task (MSIT), as a particular cognitive task, is a well-established experimental paradigm used to evaluate interference resolution. Studies combining the MSIT with functional magnetic resonance imaging (fMRI) have shown that the MSIT evokes the dorsal anterior cingulate cortex (dACC) and cingulate-frontal-parietal cognitive-attentional networks. However, these brain areas have not been evaluated quantitatively and these findings have not been replicated. In the current study, we firstly report a voxel-based meta-analysis of functional brain activation associated with the MSIT so as to identify the localization of interference resolution in such a specific cognitive task. Articles on MSIT-related fMRI published between 2003 and July 2017 were eligible. The electronic databases searched included PubMed, Web of Knowledge, and Google Scholar. Differential BOLD activation patterns between the incongruent and congruent condition were meta-analyzed in anisotropic effect-size signed differential mapping software. Robustness meta-analysis indicated that two significant activation clusters were shown to have reliable functional activity in comparisons between incongruent and congruent conditions. The first reliable activation cluster, which included the dACC, medial prefrontal cortex, supplementary motor area, replicated the previous MSIT-related fMRI study results. Furthermore, we found another reliable activation cluster comprising areas of the right insula, right inferior frontal gyrus, and right lenticular nucleus-putamen, which were not typically discussed in previous MSIT-related fMRI studies. The current meta-analysis study presents the reliable brain activation patterns

Effects of Mobile Devices on K-12 Students' Achievement: A Meta-Analysis

Science.gov (United States)

Tingir, S.; Cavlazoglu, B.; Caliskan, O.; Koklu, O.; Intepe-Tingir, S.

2017-01-01

In this meta-analytic study, we investigated the effects of mobile devices on student achievement in science, mathematics and reading in grades K-12. Based on our inclusion criteria, we searched the ERIC and PsycINFO databases and identified 14 peer-reviewed research articles published between 2010 and 2014. We identified the device type, subject…

Gain-Framed Messages Do Not Motivate Sun Protection: A Meta-Analytic Review of Randomized Trials Comparing Gain-Framed and Loss-Framed Appeals for Promoting Skin Cancer Prevention

Science.gov (United States)

O’Keefe, Daniel J.; Wu, Daisy

2012-01-01

Persuading people to undertake actions to prevent skin cancer is an important public health challenge. A number of studies have compared the effectiveness of gain-framed and loss-framed appeals in this domain, often expecting gain-framed appeals to be more persuasive. A meta-analytic review (k = 33, N = 4,168), however, finds no significant difference in the persuasiveness of gain- and loss-framed appeals for encouraging skin cancer prevention. This conclusion is unaffected by differences in the specific protective action advocated or by differences in the kind of outcomes invoked. But the results offer an intimation that men might be more susceptible to framing variations in this domain—with loss-framed appeals potentially having a persuasive advantage. PMID:22829794

Economic and Health Predictors of National Postpartum Depression Prevalence: A Systematic Review, Meta-analysis, and Meta-Regression of 291 Studies from 56 Countries

Directory of Open Access Journals (Sweden)

Jennifer Hahn-Holbrook

2018-02-01

Full Text Available BackgroundPostpartum depression (PPD poses a major global public health challenge. PPD is the most common complication associated with childbirth and exerts harmful effects on children. Although hundreds of PPD studies have been published, we lack accurate global or national PPD prevalence estimates and have no clear account of why PPD appears to vary so dramatically between nations. Accordingly, we conducted a meta-analysis to estimate the global and national prevalence of PPD and a meta-regression to identify economic, health, social, or policy factors associated with national PPD prevalence.MethodsWe conducted a systematic review of all papers reporting PPD prevalence using the Edinburgh Postnatal Depression Scale. PPD prevalence and methods were extracted from each study. Random effects meta-analysis was used to estimate global and national PPD prevalence. To test for country level predictors, we drew on data from UNICEF, WHO, and the World Bank. Random effects meta-regression was used to test national predictors of PPD prevalence.Findings291 studies of 296284 women from 56 countries were identified. The global pooled prevalence of PPD was 17.7% (95% confidence interval: 16.6–18.8%, with significant heterogeneity across nations (Q = 16,823, p = 0.000, I2 = 98%, ranging from 3% (2–5% in Singapore to 38% (35–41% in Chile. Nations with significantly higher rates of income inequality (R2 = 41%, maternal mortality (R2 = 19%, infant mortality (R2 = 16%, or women of childbearing age working ≥40 h a week (R2 = 31% have higher rates of PPD. Together, these factors explain 73% of the national variation in PPD prevalence.InterpretationThe global prevalence of PPD is greater than previously thought and varies dramatically by nation. Disparities in wealth inequality and maternal-child-health factors explain much of the national variation in PPD prevalence.

Studi Meta Analisa: Strategi Rehearsal Dan Memori Jangka Pendek

OpenAIRE

Suparmi, Suparmi

2010-01-01

This article is a study meta analysis of the experimental literature that has examined the effect of rehearsal strategy to improve short-term memory. It reviewed 59 studies from 13 journals. The population are 1341 people with down syndrome and children with specifict language impairmen, who included in special school and mainstream school, and 3487 students and graduated students. The meta analysis shows that strategy rehearsal have moderate impact on short-term memory on individu with...

Contour plot assessment of existing meta-analyses confirms robust association of statin use and acute kidney injury risk.

Science.gov (United States)

Chevance, Aurélie; Schuster, Tibor; Steele, Russell; Ternès, Nils; Platt, Robert W

2015-10-01

Robustness of an existing meta-analysis can justify decisions on whether to conduct an additional study addressing the same research question. We illustrate the graphical assessment of the potential impact of an additional study on an existing meta-analysis using published data on statin use and the risk of acute kidney injury. A previously proposed graphical augmentation approach is used to assess the sensitivity of the current test and heterogeneity statistics extracted from existing meta-analysis data. In addition, we extended the graphical augmentation approach to assess potential changes in the pooled effect estimate after updating a current meta-analysis and applied the three graphical contour definitions to data from meta-analyses on statin use and acute kidney injury risk. In the considered example data, the pooled effect estimates and heterogeneity indices demonstrated to be considerably robust to the addition of a future study. Supportingly, for some previously inconclusive meta-analyses, a study update might yield statistically significant kidney injury risk increase associated with higher statin exposure. The illustrated contour approach should become a standard tool for the assessment of the robustness of meta-analyses. It can guide decisions on whether to conduct additional studies addressing a relevant research question. Copyright © 2015 Elsevier Inc. All rights reserved.

Internal and external factors affecting photosynthetic pigment composition in plants: a meta-analytical approach.

Science.gov (United States)

Esteban, Raquel; Barrutia, Oihana; Artetxe, Unai; Fernández-Marín, Beatriz; Hernández, Antonio; García-Plazaola, José Ignacio

2015-04-01

Photosynthetic pigment composition has been a major study target in plant ecophysiology during the last three decades. Although more than 2000 papers have been published, a comprehensive evaluation of the responses of photosynthetic pigment composition to environmental conditions is not yet available. After an extensive survey, we compiled data from 525 papers including 809 species (subkingdom Viridiplantae) in which pigment composition was described. A meta-analysis was then conducted to assess the ranges of photosynthetic pigment content. Calculated frequency distributions of pigments were compared with those expected from the theoretical pigment composition. Responses to environmental factors were also analysed. The results revealed that lutein and xanthophyll cycle pigments (VAZ) were highly responsive to the environment, emphasizing the high phenotypic plasticity of VAZ, whereas neoxanthin was very stable. The present meta-analysis supports the existence of relatively narrow limits for pigment ratios and also supports the presence of a pool of free 'unbound' VAZ. Results from this study provide highly reliable ranges of photosynthetic pigment contents as a framework for future research on plant pigments. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

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.

Attachment representations in mothers, fathers, adolescents, and clinical groups : A meta-analytic search for normative data.

NARCIS (Netherlands)

IJzendoorn, van M.H.; Bakermans-Kranenburg, M.J.

1996-01-01

This meta-analysis on 33 studies, including more than 2,000 Adult Attachment Interview (AAI) classifications, presents distributions of AAI classifications in samples of nonclinical fathers and mothers, in adolescents, in samples from different cultures, and in clinical groups. Fathers, adolescents,

Grain yield increase in cereal variety mixtures: A meta-analysis of field trials

DEFF Research Database (Denmark)

Kiær, Lars Pødenphant; Skovgaard, Ib; Østergård, Hanne

2009-01-01

on grain yield. To investigate the prevalence and preconditions for positive mixing effects, reported grain yields of variety mixtures and pure variety stands were obtained from previously published variety trials, converted into relative mixing effects and combined using meta-analysis. Furthermore...... as meeting the criteria for inclusion in the meta-analysis; on the other hand, nearly 200 studies were discarded. The accepted studies reported results on both winter and spring types of each crop species. Relative mixing effects ranged from 30% to 100% with an overall meta-estimate of at least 2.7% (p