WorldWideScience

Sample records for non-rct studies meta-analyses

  1. Meta-analyses including non-randomized studies of therapeutic interventions: a methodological review

    Directory of Open Access Journals (Sweden)

    Timor Faber

    2016-03-01

    Full Text Available Abstract Background There is an increasing number of meta-analyses including data from non-randomized studies for therapeutic evaluation. We aimed to systematically assess the methods used in meta-analyses including non-randomized studies evaluating therapeutic interventions. Methods For this methodological review, we searched MEDLINE via PubMed, from January 1, 2013 to December 31, 2013 for meta-analyses including at least one non-randomized study evaluating therapeutic interventions. Etiological assessments and meta-analyses with no comparison group were excluded. Two reviewers independently assessed the general characteristics and key methodological components of the systematic review process and meta-analysis methods. Results One hundred eighty eight meta-analyses were selected: 119 included both randomized controlled trials (RCTs and non-randomized studies of interventions (NRSI and 69 only NRSI. Half of the meta-analyses (n = 92, 49 % evaluated non-pharmacological interventions. “Grey literature” was searched for 72 meta-analyses (38 %. An assessment of methodological quality or risk of bias was reported in 135 meta-analyses (72 % but this assessment considered the risk of confounding bias in only 33 meta-analyses (18 %. In 130 meta-analyses (69 %, the design of each NRSI was not clearly specified. In 131 (70 %, whether crude or adjusted estimates of treatment effect for NRSI were combined was unclear or not reported. Heterogeneity across studies was assessed in 182 meta-analyses (97 % and further explored in 157 (84 %. Reporting bias was assessed in 127 (68 %. Conclusions Some key methodological components of the systematic review process—search for grey literature, description of the type of NRSI included, assessment of risk of confounding bias and reporting of whether crude or adjusted estimates were combined—are not adequately carried out or reported in meta-analyses including NRSI.

  2. The impact of study size on meta-analyses: examination of underpowered studies in Cochrane reviews.

    Directory of Open Access Journals (Sweden)

    Rebecca M Turner

    Full Text Available Most meta-analyses include data from one or more small studies that, individually, do not have power to detect an intervention effect. The relative influence of adequately powered and underpowered studies in published meta-analyses has not previously been explored. We examine the distribution of power available in studies within meta-analyses published in Cochrane reviews, and investigate the impact of underpowered studies on meta-analysis results.For 14,886 meta-analyses of binary outcomes from 1,991 Cochrane reviews, we calculated power per study within each meta-analysis. We defined adequate power as ≥50% power to detect a 30% relative risk reduction. In a subset of 1,107 meta-analyses including 5 or more studies with at least two adequately powered and at least one underpowered, results were compared with and without underpowered studies. In 10,492 (70% of 14,886 meta-analyses, all included studies were underpowered; only 2,588 (17% included at least two adequately powered studies. 34% of the meta-analyses themselves were adequately powered. The median of summary relative risks was 0.75 across all meta-analyses (inter-quartile range 0.55 to 0.89. In the subset examined, odds ratios in underpowered studies were 15% lower (95% CI 11% to 18%, P<0.0001 than in adequately powered studies, in meta-analyses of controlled pharmacological trials; and 12% lower (95% CI 7% to 17%, P<0.0001 in meta-analyses of controlled non-pharmacological trials. The standard error of the intervention effect increased by a median of 11% (inter-quartile range -1% to 35% when underpowered studies were omitted; and between-study heterogeneity tended to decrease.When at least two adequately powered studies are available in meta-analyses reported by Cochrane reviews, underpowered studies often contribute little information, and could be left out if a rapid review of the evidence is required. However, underpowered studies made up the entirety of the evidence in most

  3. A systematic review evaluating the methodological aspects of meta-analyses of genetic association studies in cancer research

    OpenAIRE

    Boccia, Stefania; De Feo, Emma; Gallì, Paola; Gianfagna, Francesco; Amore, Rosarita; Ricciardi, Gualtiero

    2010-01-01

    Abstract Meta-analyses and Individual Patient Data (IPD) meta-analyses of genetic association studies are a powerful tool to summarize the scientific evidences, however their application present considerable potential and several pitfalls. We reviewed systematically all published meta-analyses and IPD meta-analyses of genetic association studies in the field of cancer research, searching for relevant studies on the Medline, Embase, and HuGE Reviews Archive databases until January 2...

  4. Meta-Analyses of Animal Studies: An Introduction of a Valuable Instrument to Further Improve Healthcare

    Science.gov (United States)

    Hooijmans, Carlijn R.; IntHout, Joanna; Ritskes-Hoitinga, Merel; Rovers, Maroeska M.

    2014-01-01

    In research aimed at improving human health care, animal studies still play a crucial role, despite political and scientific efforts to reduce preclinical experimentation in laboratory animals. In animal studies, the results and their interpretation are not always straightforward, as no single study is executed perfectly in all steps. There are several possible sources of bias, and many animal studies are replicates of studies conducted previously. Use of meta-analysis to combine the results of studies may lead to more reliable conclusions and a reduction of unnecessary duplication of animal studies. In addition, due to the more exploratory nature of animal studies as compared to clinical trials, meta-analyses of animal studies have greater potential in exploring possible sources of heterogeneity. There is an abundance of literature on how to perform meta-analyses on clinical data. Animal studies, however, differ from clinical studies in some aspects, such as the diversity of animal species studied, experimental design, and study characteristics. In this paper, we will discuss the main principles and practices for meta-analyses of experimental animal studies. PMID:25541544

  5. Disorganized Systematic Reviews and Meta-analyses: Time to Systematize the Conduct and Publication of These Study Overviews?

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    Riaz, Irbaz Bin; Khan, Muhammad Shahzeb; Riaz, Haris; Goldberg, Robert J

    2016-03-01

    The number of meta-analyses published annually has increased more than 20-fold between 1994 (n = 386) and 2014 (n = 8203). In examining how much of this increase in meta-analysis publication has genuinely represented novel contributions to clinical medicine and public health, it became clear that there was an abundance of redundant and disorganized meta-analyses, creating confusion and generating considerable debate. Ironically, meta-analyses, which should prevent redundant research, have become a victim of it. Recently, 17 meta-analyses were published based on the results of only 3 randomized controlled trials that studied the role of transcatheter closure of patent foramen ovale for prevention of cryptogenic stroke. In our search of the published literature, we identified at least 10 topics that were the subject of 10 meta-analyses. In the context of overlapping meta-analyses, one questions what needs to be done to put this "runaway train" back on track. In this review we examine the practice of redundant meta-analyses and the reasons for its disturbing "popularity." The registration of systematic reviews should be mandatory in prospective registries, such as PROSPERO, and the PRISMA checklist should be updated to incorporate new evidence and mandate the reference of previously published reviews and rationale for any new study.

  6. Meta-Analyses of Human Cell-Based Cardiac Regeneration Therapies: Controversies in Meta-Analyses Results on Cardiac Cell-Based Regenerative Studies.

    Science.gov (United States)

    Gyöngyösi, Mariann; Wojakowski, Wojciech; Navarese, Eliano P; Moye, Lemuel À

    2016-04-15

    In contrast to multiple publication-based meta-analyses involving clinical cardiac regeneration therapy in patients with recent myocardial infarction, a recently published meta-analysis based on individual patient data reported no effect of cell therapy on left ventricular function or clinical outcome. A comprehensive review of the data collection, statistics, and the overall principles of meta-analyses provides further clarification and explanation for this controversy. The advantages and pitfalls of different types of meta-analyses are reviewed here. Each meta-analysis approach has a place when pivotal clinical trials are lacking and sheds light on the magnitude of the treatment in a complex healthcare field.

  7. Disagreements in meta-analyses using outcomes measured on continuous or rating scales: observer agreement study

    DEFF Research Database (Denmark)

    Tendal, Britta; Higgins, Julian P T; Jüni, Peter

    2009-01-01

    OBJECTIVE: To study the inter-observer variation related to extraction of continuous and numerical rating scale data from trial reports for use in meta-analyses. DESIGN: Observer agreement study. DATA SOURCES: A random sample of 10 Cochrane reviews that presented a result as a standardised mean...... difference (SMD), the protocols for the reviews and the trial reports (n=45) were retrieved. DATA EXTRACTION: Five experienced methodologists and five PhD students independently extracted data from the trial reports for calculation of the first SMD result in each review. The observers did not have access...

  8. Meta-analyses

    NARCIS (Netherlands)

    Hendriks, M.A.; Luyten, J.W.; Scheerens, J.; Sleegers, P.J.C.; Scheerens, J.

    2014-01-01

    In this chapter results of a research synthesis and quantitative meta-analyses of three facets of time effects in education are presented, namely time at school during regular lesson hours, homework, and extended learning time. The number of studies for these three facets of time that could be used

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

    Directory of Open Access Journals (Sweden)

    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

  10. Intelligence and handedness: Meta-analyses of studies on intellectually disabled, typically developing, and gifted individuals.

    Science.gov (United States)

    Papadatou-Pastou, Marietta; Tomprou, Dimitra-Maria

    2015-09-01

    Understanding the relationship between cerebral laterality and intelligence is important in elucidating the neurological underpinnings of individual differences in cognitive abilities. A widely used, behavioral indicator for cerebral laterality, mainly of language, is handedness. A number of studies have compared cognitive abilities between groups of left- and right-handers, while others have investigated the handedness prevalence between groups of different cognitive abilities. The present study comprises five meta-analyses of studies that have assessed the handedness prevalence in (a) individuals with intellectual disability (ID) of unknown/idiopathic nature compared to typically developing (TD) individuals, and (b) individuals with intellectual giftedness (IG) compared to TD individuals. Nineteen data sets totaling 16,076 participants (5795 ID, 8312 TD, and 1969 IG) were included in the analyses. Elevated levels of atypical handedness were found to be robust only for the ID to TD comparison. Findings constrain the range of acceptable theories on the handedness distribution for different intelligence levels.

  11. Dietary supplement use and colorectal cancer risk: A systematic review and meta-analyses of prospective cohort studies

    NARCIS (Netherlands)

    Heine-Bröring, R.C.; Winkels, R.M.; Renkema, J.M.S.; Kragt, L.; Orten-Luiten, van A.C.B.; Tigchelaar, E.F.; Chan, D.S.M.; Norat, T.; Kampman, E.

    2015-01-01

    Use of dietary supplements is rising in countries where colorectal cancer is prevalent. We conducted a systematic literature review and meta-analyses of prospective cohort studies on dietary supplement use and colorectal cancer risk. We identified relevant studies in Medline, Embase and Cochrane up

  12. Dietary supplement use and colorectal cancer risk: A systematic review and meta-analyses of prospective cohort studies

    NARCIS (Netherlands)

    Heine-Bröring, R.C.; Winkels, R.M.; Renkema, J.M.S.; Kragt, L.; Orten-Luiten, van A.C.B.; Tigchelaar, E.F.; Chan, D.S.M.; Norat, T.; Kampman, E.

    2015-01-01

    Use of dietary supplements is rising in countries where colorectal cancer is prevalent. We conducted a systematic literature review and meta-analyses of prospective cohort studies on dietary supplement use and colorectal cancer risk. We identified relevant studies in Medline, Embase and Cochrane up

  13. Uptake of systematic reviews and meta-analyses based on individual participant data in clinical practice guidelines: descriptive study

    NARCIS (Netherlands)

    Vale, C.L.; Rydzewska, L.H.; Rovers, M.M.; Emberson, J.R.; Gueyffier, F.; Stewart, L.A.

    2015-01-01

    OBJECTIVE: To establish the extent to which systematic reviews and meta-analyses of individual participant data (IPD) are being used to inform the recommendations included in published clinical guidelines. DESIGN: Descriptive study. SETTING: Database maintained by the Cochrane IPD Meta-analysis Meth

  14. Association between Adult Height and Risk of Colorectal, Lung, and Prostate Cancer : Results from Meta-analyses of Prospective Studies and Mendelian Randomization Analyses

    NARCIS (Netherlands)

    Khankari, Nikhil K.; Shu, Xiao Ou; Wen, Wanqing; Kraft, Peter; Lindström, Sara; Peters, Ulrike; Schildkraut, Joellen; Schumacher, Fredrick; Bofetta, Paolo; Risch, Angela; Bickeböller, Heike; Amos, Christopher I.; Easton, Douglas; Eeles, Rosalind A.; Gruber, Stephen B.; Haiman, Christopher A.; Hunter, David J.; Chanock, Stephen J.; Pierce, Brandon L.; Zheng, Wei; Blalock, Kendra; Campbell, Peter T.; Casey, Graham; Conti, David V.; Edlund, Christopher K.; Figueiredo, Jane; James Gauderman, W.; Gong, Jian; Green, Roger C.; Harju, John F.; Harrison, Tabitha A.; Jacobs, Eric J.; Jenkins, Mark A.; Jiao, Shuo; Li, Li; Lin, Yi; Manion, Frank J.; Moreno, Victor; Mukherjee, Bhramar; Raskin, Leon; Schumacher, Fredrick R.; Seminara, Daniela; Severi, Gianluca; Stenzel, Stephanie L.; Thomas, Duncan C.; Hopper, John L.; Southey, Melissa C.; Makalic, Enes; Schmidt, Daniel F.; Fletcher, Olivia; Peto, Julian; Gibson, Lorna; dos Santos Silva, Isabel; Ahsan, Habib; Whittemore, Alice; Waisfisz, Quinten; Meijers-Heijboer, Hanne; Adank, Muriel; van der Luijt, Rob B.; Uitterlinden, Andre G.; Hofman, Albert; Meindl, Alfons; Schmutzler, Rita K.; Müller-Myhsok, Bertram; Lichtner, Peter; Nevanlinna, Heli; Muranen, Taru A.; Aittomäki, Kristiina; Blomqvist, Carl; Chang-Claude, Jenny; Hein, Rebecca; Dahmen, Norbert; Beckman, Lars; Crisponi, Laura; Hall, Per; Czene, Kamila; Irwanto, Astrid; Liu, Jianjun; Easton, Douglas F.; Turnbull, Clare; Rahman, Nazneen; Eeles, Rosalind; Kote-Jarai, Zsofia; Muir, Kenneth; Giles, Graham; Neal, David; Donovan, Jenny L.; Hamdy, Freddie C.; Wiklund, Fredrik; Gronberg, Henrik; Haiman, Christopher; Schumacher, Fred; Travis, Ruth; Riboli, Elio; Hunter, David; Gapstur, Susan; Berndt, Sonja; Chanock, Stephen; Han, Younghun; Su, Li; Wei, Yongyue; Hung, Rayjean J.; Brhane, Yonathan; McLaughlin, John; Brennan, Paul; McKay, James D.; Rosenberger, Albert; Houlston, Richard S.; Caporaso, Neil; Teresa Landi, Maria; Heinrich, Joachim; Wu, Xifeng; Ye, Yuanqing; Christiani, David C.

    2016-01-01

    Background: Observational studies examining associations between adult height and risk of colorectal, prostate, and lung cancers have generated mixed results. We conducted meta-analyses using data from prospective cohort studies and further carried out Mendelian randomization analyses, using height-

  15. Not all risks are created equal: A twin study and meta-analyses of risk taking across seven domains.

    Science.gov (United States)

    Wang, X T Xiao-Tian; Zheng, Rui; Xuan, Yan-Hua; Chen, Jie; Li, Shu

    2016-11-01

    Humans routinely deal with both traditional and novel risks. Different kinds of risks have been a driving force for both evolutionary adaptations and personal development. This study explored the genetic and environmental influences on human risk taking in different task domains. Our approach was threefold. First, we integrated several scales of domain-specific risk-taking propensity and developed a synthetic scale, including both evolutionarily typical and modern risks in the following 7 domains: cooperation/competition, safety, reproduction, natural/physical risk, moral risk, financial risk, and gambling. Second, we conducted a twin study using the scale to estimate the contributions of genes and environment to risk taking in each of these 7 domains. Third, we conducted a series of meta-analyses of extant twin studies across the 7 risk domains. The results showed that individual differences in risk-taking propensity and its consistency across domains were mainly regulated by additive genetic influences and individually unique environmental experiences. The heritability estimates from the meta-analyses ranged from 29% in financial risk taking to 55% in safety. Supporting the notion of risk-domain specificity, both the behavioral and genetic correlations among the 7 domains were generally low. Among the relatively few correlations between pairs of risk domains, our analysis revealed a common genetic factor that regulates moral, financial, and natural/physical risk taking. This is the first effort to separate genetic and environmental influences on risk taking across multiple domains in a single study and integrate the findings of extant twin studies via a series of meta-analyses conducted in different task domains. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  16. Low-density lipoprotein cholesterol and risk of gallstone disease: a Mendelian randomization study and meta-analyses.

    Science.gov (United States)

    Stender, Stefan; Frikke-Schmidt, Ruth; Benn, Marianne; Nordestgaard, Børge G; Tybjærg-Hansen, Anne

    2013-01-01

    Drugs which reduce plasma low-density lipoprotein cholesterol (LDL-C) may protect against gallstone disease. Whether plasma levels of LDL-C per se predict risk of gallstone disease remains unclear. We tested the hypothesis that elevated LDL-C is a causal risk factor for symptomatic gallstone disease. We used a Mendelian randomization approach and genotyped 63,051 individuals from a prospective cohort study of the general Danish population, including 3323 subjects with symptomatic gallstones. We selected eight genetic variants in APOE, APOB, LDLR, and PCSK9 affecting LDL-C. Furthermore, studies of APOE rs429358/rs7412 (defining ε2/ε3/ε4 alleles; 12 studies) and APOB rs693 (eight studies) were included in meta-analyses. The observational hazard ratio (HR) for symptomatic gallstone disease for the fifth versus first quintile of LDL-C was 0.94 (95% confidence interval: 0.76-1.17), despite a corresponding 134% increase in LDL-C. Furthermore, although individual genetic variants in APOE, APOB, LDLR, and PCSK9 associated with stepwise increases/decreases in LDL-C of up to +59% compared with non-carriers (p gallstone disease. Combining all variants into 10 genotypes, carriers of 9 versus ⩽3 LDL-C increasing alleles associated with 41% increased LDL-C (p gallstone disease of 1.09 (0.70-1.69). Finally, in meta-analyses, random effects odds ratios for gallstone disease were 0.91 (0.78-1.06) for carriers of APOE ε4 versus non-carriers, and 1.25 (0.95-1.63) for APOB rs693 CT+TT versus CC. Results from the observational study, genetic studies, and meta-analyses suggest that elevated plasma levels of LDL-C are not causally associated with increased risk of symptomatic gallstone disease. Copyright © 2012 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  17. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration.

    Directory of Open Access Journals (Sweden)

    Alessandro Liberati

    2009-07-01

    Full Text Available Systematic reviews and meta-analyses are essential to summarize evidence relating to efficacy and safety of health care interventions accurately and reliably. The clarity and transparency of these reports, however, is not optimal. Poor reporting of systematic reviews diminishes their value to clinicians, policy makers, and other users.Since the development of the QUOROM (QUality Of Reporting Of Meta-analysis Statement--a reporting guideline published in 1999--there have been several conceptual, methodological, and practical advances regarding the conduct and reporting of systematic reviews and meta-analyses. Also, reviews of published systematic reviews have found that key information about these studies is often poorly reported. Realizing these issues, an international group that included experienced authors and methodologists developed PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses as an evolution of the original QUOROM guideline for systematic reviews and meta-analyses of evaluations of health care interventions.The PRISMA Statement consists of a 27-item checklist and a four-phase flow diagram. The checklist includes items deemed essential for transparent reporting of a systematic review. In this Explanation and Elaboration document, we explain the meaning and rationale for each checklist item. For each item, we include an example of good reporting and, where possible, references to relevant empirical studies and methodological literature. The PRISMA Statement, this document, and the associated Web site (http://www.prisma-statement.org/ should be helpful resources to improve reporting of systematic reviews and meta-analyses.

  18. Serum Iron, Zinc, and Copper Levels in Patients with Alzheimer's Disease: A Replication Study and Meta-Analyses.

    Science.gov (United States)

    Wang, Zi-Xuan; Tan, Lan; Wang, Hui-Fu; Ma, Jing; Liu, Jinyuan; Tan, Meng-Shan; Sun, Jia-Hao; Zhu, Xi-Chen; Jiang, Teng; Yu, Jin-Tai

    2015-01-01

    To evaluate whether iron, zinc, and copper levels in serum are disarranged in Alzheimer's disease (AD), we performed meta-analyses of all studies on the topic published from 1984 to 2014 and contextually carried out a replication study in serum as well. Our meta-analysis results showed that serum zinc was significantly lower in AD patients. Our replication and meta-analysis results showed that serum copper was significantly higher in AD patients than in healthy controls, so our findings were consistent with the conclusions of four previously published copper meta-analyses. Even if a possible role of iron in the pathophysiology of the disease could not be ruled out, the results of our meta-analysis showed no change of serum iron levels in AD patients, but this conclusion was not robust and requires further investigation. The meta-regression analyses revealed that in some studies, differences in serum iron levels could be due to the different mean ages, while differences in zinc levels appeared to be due to the different sex ratios. However, the effect of sex ratio on serum zinc levels in our meta-analysis is subtle and needs further confirmation. Also, diverse demographic terms and methodological approaches appeared not to explain the high heterogeneity of our copper meta-analysis. Therefore, when investigating trace elements, covariants such as age and sex have to be taken into account in the analyses. In the light of these findings, we suggest that the possible alteration of serum zinc and copper levels are involved in the pathogenesis of AD.

  19. Characteristics of meta-analyses and their component studies in the Cochrane Database of Systematic Reviews: a cross-sectional, descriptive analysis

    Directory of Open Access Journals (Sweden)

    Davey Jonathan

    2011-11-01

    Full Text Available Abstract Background Cochrane systematic reviews collate and summarise studies of the effects of healthcare interventions. The characteristics of these reviews and the meta-analyses and individual studies they contain provide insights into the nature of healthcare research and important context for the development of relevant statistical and other methods. Methods We classified every meta-analysis with at least two studies in every review in the January 2008 issue of the Cochrane Database of Systematic Reviews (CDSR according to the medical specialty, the types of interventions being compared and the type of outcome. We provide descriptive statistics for numbers of meta-analyses, numbers of component studies and sample sizes of component studies, broken down by these categories. Results We included 2321 reviews containing 22,453 meta-analyses, which themselves consist of data from 112,600 individual studies (which may appear in more than one meta-analysis. Meta-analyses in the areas of gynaecology, pregnancy and childbirth (21%, mental health (13% and respiratory diseases (13% are well represented in the CDSR. Most meta-analyses address drugs, either with a control or placebo group (37% or in a comparison with another drug (25%. The median number of meta-analyses per review is six (inter-quartile range 3 to 12. The median number of studies included in the meta-analyses with at least two studies is three (inter-quartile range 2 to 6. Sample sizes of individual studies range from 2 to 1,242,071, with a median of 91 participants. Discussion It is clear that the numbers of studies eligible for meta-analyses are typically very small for all medical areas, outcomes and interventions covered by Cochrane reviews. This highlights the particular importance of suitable methods for the meta-analysis of small data sets. There was little variation in number of studies per meta-analysis across medical areas, across outcome data types or across types of

  20. Genome-Wide Meta-Analyses of Breast, Ovarian, and Prostate Cancer Association Studies Identify Multiple New Susceptibility Loci Shared by at Least Two Cancer Types

    NARCIS (Netherlands)

    Kar, S.P.; Beesley, J.; Olama, A. Amin Al; Michailidou, K.; Tyrer, J.; Kote-Jarai, Z.; Lawrenson, K.; Lindstrom, S.; Ramus, S.J.; Thompson, D.J.; Kibel, A.S.; Dansonka-Mieszkowska, A.; Michael, A.; Dieffenbach, A.K.; Gentry-Maharaj, A.; Whittemore, A.S.; Wolk, A.; Monteiro, A.; Peixoto, A.; Kierzek, A.; Cox, A; Rudolph, A.; Gonzalez-Neira, A.; Wu, A.H.; Lindblom, A.; Swerdlow, A.; Ziogas, A.; Ekici, A.B.; Burwinkel, B.; Karlan, B.Y.; Nordestgaard, B.G.; Blomqvist, C.; Phelan, C.; McLean, C.; Pearce, C.L.; Vachon, C.; Cybulski, C.; Slavov, C.; Stegmaier, C.; Maier, C.; Ambrosone, C.B.; Hogdall, C.K.; Teerlink, C.C.; Kang, D.; Tessier, D.C.; Schaid, D.J.; Stram, D.O.; Cramer, D.W; Neal, D.E.; Eccles, D.; Flesch-Janys, D.; Edwards, D.R.; Wokozorczyk, D.; Levine, D.A.; Yannoukakos, D.; Sawyer, E.J.; Bandera, E.V.; Poole, E.M.; Goode, E.L.; Khusnutdinova, E.; Hogdall, E.; Song, F.; Bruinsma, F.; Heitz, F.; Modugno, F.; Hamdy, F.C.; Wiklund, F.; Giles, G.G.; Olsson, H.; Wildiers, H.; Ulmer, H.U.; Pandha, H.; Risch, H.A.; Darabi, H.; Salvesen, H.B.; Nevanlinna, H.; Gronberg, H.; Brenner, H.; Brauch, H.; Anton-Culver, H.; Song, H.; Lim, H.Y.; McNeish, I.; Campbell, I.; Vergote, I.; Gronwald, J.; Lubinski, J.; Stanford, J.L.; Benitez, J.; Doherty, J.A.; Permuth, J.B.; Chang-Claude, J.; Donovan, J.L.; Dennis, J.; Schildkraut, J.M.; Schleutker, J.; Hopper, J.L.; Kupryjanczyk, J.; Park, J.Y.; Figueroa, J.; Kiemeney, L.A.; Massuger, L.F.A.G.

    2016-01-01

    Breast, ovarian, and prostate cancers are hormone-related and may have a shared genetic basis, but this has not been investigated systematically by genome-wide association (GWA) studies. Meta-analyses combining the largest GWA meta-analysis data sets for these cancers totaling 112,349 cases and

  1. Systematic meta-analyses and field synopsis of genetic and epigenetic studies in paediatric inflammatory bowel disease

    Science.gov (United States)

    Li, Xue; Song, Peige; Timofeeva, Maria; Meng, Xiangrui; Rudan, Igor; Little, Julian; Satsangi, Jack; Campbell, Harry; Theodoratou, Evropi

    2016-01-01

    We provide a comprehensive field synopsis of genetic and epigenetic associations for paediatric Inflammatory Bowel Disease (IBD). A systematic review was performed and included 84 genetic association studies reporting data for 183 polymorphisms in 71 genes. Meta-analyses were conducted for 20 SNPs in 10 genes of paediatric Crohn’s disease (CD) and for 8 SNPs in 5 genes of paediatric ulcerative colitis (UC). Five epigenetic studies were also included, but formal meta-analysis was not possible. Venice criteria and Bayesian false discovery probability test were applied to assess the credibility of associations. Nine SNPs in 4 genes were considered to have highly credible associations with paediatric CD, of which four variants (rs2066847, rs12521868, rs26313667, rs1800629) were not previously identified in paediatric GWAS. Differential DNA methylation in NOD2 and TNF-α, dysregulated expression in let-7 and miR-124 were associated with paediatric IBD, but not as yet replicated. Highly credible SNPs associated with paediatric IBD have also been implicated in adult IBD, with similar magnitudes of associations. Early onset and distinct phenotypic features of paediatric IBD might be due to distinct epigenetic changes, but these findings need to be replicated. Further progress identifying genetic and epigenetic susceptibility of paediatric IBD will require international collaboration, population diversity and harmonization of protocols. PMID:27670835

  2. Meta-analyses of genome-wide association studies identify multiple loci associated with pulmonary function.

    Science.gov (United States)

    Hancock, Dana B; Eijgelsheim, Mark; Wilk, Jemma B; Gharib, Sina A; Loehr, Laura R; Marciante, Kristin D; Franceschini, Nora; van Durme, Yannick M T A; Chen, Ting-Hsu; Barr, R Graham; Schabath, Matthew B; Couper, David J; Brusselle, Guy G; Psaty, Bruce M; van Duijn, Cornelia M; Rotter, Jerome I; Uitterlinden, André G; Hofman, Albert; Punjabi, Naresh M; Rivadeneira, Fernando; Morrison, Alanna C; Enright, Paul L; North, Kari E; Heckbert, Susan R; Lumley, Thomas; Stricker, Bruno H C; O'Connor, George T; London, Stephanie J

    2010-01-01

    Spirometric measures of lung function are heritable traits that reflect respiratory health and predict morbidity and mortality. We meta-analyzed genome-wide association studies for two clinically important lung-function measures: forced expiratory volume in the first second (FEV(1)) and its ratio to forced vital capacity (FEV(1)/FVC), an indicator of airflow obstruction. This meta-analysis included 20,890 participants of European ancestry from four CHARGE Consortium studies: Atherosclerosis Risk in Communities, Cardiovascular Health Study, Framingham Heart Study and Rotterdam Study. We identified eight loci associated with FEV(1)/FVC (HHIP, GPR126, ADAM19, AGER-PPT2, FAM13A, PTCH1, PID1 and HTR4) and one locus associated with FEV(1) (INTS12-GSTCD-NPNT) at or near genome-wide significance (P < 5 x 10(-8)) in the CHARGE Consortium dataset. Our findings may offer insights into pulmonary function and pathogenesis of chronic lung disease.

  3. Meta-analyses of genome-wide association studies identify multiple loci associated with pulmonary function

    NARCIS (Netherlands)

    D.B. Hancock (Dana); M. Eijgelsheim (Mark); J.B. Wilk (Jemma); S.A. Gharib (Sina); L.R. Loehr (Laura); K. Marciante (Kristin); N. Franceschini (Nora); Y.M.T.A. van Durme; T.H. Chen; R.G. Barr (Graham); M.B. Schabath (Matthew); D.J. Couper (David); G.G. Brusselle (Guy); B.M. Psaty (Bruce); P. Tikka-Kleemola (Päivi); J.I. Rotter (Jerome); A.G. Uitterlinden (André); A. Hofman (Albert); N.M. Punjabi (Naresh); F. Rivadeneira Ramirez (Fernando); A.C. Morrison (Alanna); P.L. Enright (Paul); K.E. North (Kari); S.R. Heckbert (Susan); T. Lumley (Thomas); B.H.Ch. Stricker (Bruno); G.T. O'Connor (George); S.J. London (Stephanie)

    2010-01-01

    textabstractSpirometric measures of lung function are heritable traits that reflect respiratory health and predict morbidity and mortality. We meta-analyzed genome-wide association studies for two clinically important lung-function measures: forced expiratory volume in the first second (FEV1) and it

  4. Correcting for multivariate measurement error by regression calibration in meta-analyses of epidemiological studies

    DEFF Research Database (Denmark)

    Tybjærg-Hansen, Anne

    2009-01-01

    Within-person variability in measured values of multiple risk factors can bias their associations with disease. The multivariate regression calibration (RC) approach can correct for such measurement error and has been applied to studies in which true values or independent repeat measurements of t...

  5. Systematic review with meta-analyses of studies on the association between cirrhosis and liver metastases

    DEFF Research Database (Denmark)

    Dahl, Emilie; Rumessen, Jüri; Gluud, Lise L

    2011-01-01

    (Medline, Embase, and Web of Science) and manual searches were combined (October 2010) to identify observational studies on patients with malignant disease reporting the risk of liver metastases among cases (with cirrhosis) and controls (without liver disease). Meta-analysis was performed using random...

  6. Meta-analyses of genome-wide association studies identify multiple loci associated with pulmonary function

    NARCIS (Netherlands)

    D.B. Hancock (Dana); M. Eijgelsheim (Mark); J.B. Wilk (Jemma); S.A. Gharib (Sina); L.R. Loehr (Laura); K. Marciante (Kristin); N. Franceschini (Nora); Y.M.T.A. van Durme; T.H. Chen; R.G. Barr (Graham); M.B. Schabath (Matthew); D.J. Couper (David); G.G. Brusselle (Guy); B.M. Psaty (Bruce); P. Tikka-Kleemola (Päivi); J.I. Rotter (Jerome); A.G. Uitterlinden (André); A. Hofman (Albert); N.M. Punjabi (Naresh); F. Rivadeneira Ramirez (Fernando); A.C. Morrison (Alanna); P.L. Enright (Paul); K.E. North (Kari); S.R. Heckbert (Susan); T. Lumley (Thomas); B.H.Ch. Stricker (Bruno); G.T. O'Connor (George); S.J. London (Stephanie)

    2010-01-01

    textabstractSpirometric measures of lung function are heritable traits that reflect respiratory health and predict morbidity and mortality. We meta-analyzed genome-wide association studies for two clinically important lung-function measures: forced expiratory volume in the first second (FEV1) and

  7. Quantifying the impact of between-study heterogeneity in multivariate meta-analyses

    OpenAIRE

    Jackson, Dan; White, Ian R; Riley, Richard D.

    2012-01-01

    Measures that quantify the impact of heterogeneity in univariate meta-analysis, including the very popular I 2 statistic, are now well established. Multivariate meta-analysis, where studies provide multiple outcomes that are pooled in a single analysis, is also becoming more commonly used. The question of how to quantify heterogeneity in the multivariate setting is therefore raised. It is the univariate R 2 statistic, the ratio of the variance of the estimated treatment effect under the rando...

  8. Suicidality and aggression during antidepressant treatment: systematic review and meta-analyses based on clinical study reports

    Science.gov (United States)

    Guski, Louise Schow; Freund, Nanna; Gøtzsche, Peter C

    2016-01-01

    Objective To study serious harms associated with selective serotonin and serotonin-norepinephrine reuptake inhibitors. Design Systematic review and meta-analysis. Main outcome measures Mortality and suicidality. Secondary outcomes were aggressive behaviour and akathisia. Data sources Clinical study reports for duloxetine, fluoxetine, paroxetine, sertraline, and venlafaxine obtained from the European and UK drug regulators, and summary trial reports for duloxetine and fluoxetine from Eli Lilly’s website. Eligibility criteria for study selection Double blind placebo controlled trials that contained any patient narratives or individual patient listings of harms. Data extraction and analysis Two researchers extracted data independently; the outcomes were meta-analysed by Peto’s exact method (fixed effect model). Results We included 70 trials (64 381 pages of clinical study reports) with 18 526 patients. These trials had limitations in the study design and discrepancies in reporting, which may have led to serious under-reporting of harms. For example, some outcomes appeared only in individual patient listings in appendices, which we had for only 32 trials, and we did not have case report forms for any of the trials. Differences in mortality (all deaths were in adults, odds ratio 1.28, 95% confidence interval 0.40 to 4.06), suicidality (1.21, 0.84 to 1.74), and akathisia (2.04, 0.93 to 4.48) were not significant, whereas patients taking antidepressants displayed more aggressive behaviour (1.93, 1.26 to 2.95). For adults, the odds ratios were 0.81 (0.51 to 1.28) for suicidality, 1.09 (0.55 to 2.14) for aggression, and 2.00 (0.79 to 5.04) for akathisia. The corresponding values for children and adolescents were 2.39 (1.31 to 4.33), 2.79 (1.62 to 4.81), and 2.15 (0.48 to 9.65). In the summary trial reports on Eli Lilly’s website, almost all deaths were noted, but all suicidal ideation events were missing, and the information on the remaining outcomes was

  9. Age at Menarche, Level of Education, Parity and the Risk of Hysterectomy: A Systematic Review and Meta-Analyses of Population-Based Observational Studies.

    Directory of Open Access Journals (Sweden)

    Louise F Wilson

    Full Text Available Although rates have declined, hysterectomy is still a frequent gynaecological procedure. To date, there has been no systematic quantification of the relationships between early/mid-life exposures and hysterectomy. We performed a systematic review and meta-analyses to quantify the associations between age at menarche, education level, parity and hysterectomy.Eligible studies were identified by searches in PubMed and Embase through March 2015. Study-specific estimates were summarised using random effects meta-analysis. Heterogeneity was explored using sub-group analysis and meta-regression.Thirty-two study populations were identified for inclusion in at least one meta-analysis. Each year older at menarche was associated with lower risk of hysterectomy-summary hazard ratio 0.86 (95% confidence interval: 0.78, 0.95; I2 = 0%; summary odds ratio 0.88 (95% confidence interval: 0.82, 0.94; I2 = 61%. Low education levels conferred a higher risk of hysterectomy in the lowest versus highest level meta-analysis (summary hazard ratio 1.87 (95% confidence interval: 1.25, 2.80; I2 = 86%, summary odds ratio 1.51 (95% confidence interval: 1.35, 1.69; I2 = 90% and dose-response meta-analysis (summary odds ratio 1.17 (95% confidence interval: 1.12, 1.23; I2 = 85% per each level lower of education. Sub-group analysis showed that the birth cohort category of study participants, the reference category used for level of education, the year the included article was published, quality of the study (as assessed by the authors and control for the key variables accounted for the high heterogeneity between studies in the education level meta-analyses. In the meta-analyses of studies of parity and hysterectomy the results were not statistically significant.The present meta-analyses suggest that the early life factors of age at menarche and lower education level are associated with hysterectomy, although this evidence should be interpreted with some caution due to variance

  10. On the reproducibility of meta-analyses : six practical recommendations

    NARCIS (Netherlands)

    Lakens, D.; Hilgard, J.; Staaks, J.

    2016-01-01

    Meta-analyses play an important role in cumulative science by combining information across multiple studies and attempting to provide effect size estimates corrected for publication bias. Research on the reproducibility of meta-analyses reveals that errors are common, and the percentage of effect si

  11. Association between Adult Height and Risk of Colorectal, Lung, and Prostate Cancer: Results from Meta-analyses of Prospective Studies and Mendelian Randomization Analyses

    Science.gov (United States)

    Khankari, Nikhil K.; Shu, Xiao-Ou; Wen, Wanqing; Kraft, Peter; Lindström, Sara; Peters, Ulrike; Schildkraut, Joellen; Schumacher, Fredrick; Bofetta, Paolo; Risch, Angela; Bickeböller, Heike; Amos, Christopher I.; Easton, Douglas; Gruber, Stephen B.; Haiman, Christopher A.; Hunter, David J.; Chanock, Stephen J.; Pierce, Brandon L.; Zheng, Wei

    2016-01-01

    Background Observational studies examining associations between adult height and risk of colorectal, prostate, and lung cancers have generated mixed results. We conducted meta-analyses using data from prospective cohort studies and further carried out Mendelian randomization analyses, using height-associated genetic variants identified in a genome-wide association study (GWAS), to evaluate the association of adult height with these cancers. Methods and Findings A systematic review of prospective studies was conducted using the PubMed, Embase, and Web of Science databases. Using meta-analyses, results obtained from 62 studies were summarized for the association of a 10-cm increase in height with cancer risk. Mendelian randomization analyses were conducted using summary statistics obtained for 423 genetic variants identified from a recent GWAS of adult height and from a cancer genetics consortium study of multiple cancers that included 47,800 cases and 81,353 controls. For a 10-cm increase in height, the summary relative risks derived from the meta-analyses of prospective studies were 1.12 (95% CI 1.10, 1.15), 1.07 (95% CI 1.05, 1.10), and 1.06 (95% CI 1.02, 1.11) for colorectal, prostate, and lung cancers, respectively. Mendelian randomization analyses showed increased risks of colorectal (odds ratio [OR] = 1.58, 95% CI 1.14, 2.18) and lung cancer (OR = 1.10, 95% CI 1.00, 1.22) associated with each 10-cm increase in genetically predicted height. No association was observed for prostate cancer (OR = 1.03, 95% CI 0.92, 1.15). Our meta-analysis was limited to published studies. The sample size for the Mendelian randomization analysis of colorectal cancer was relatively small, thus affecting the precision of the point estimate. Conclusions Our study provides evidence for a potential causal association of adult height with the risk of colorectal and lung cancers and suggests that certain genetic factors and biological pathways affecting adult height may also affect the

  12. Pleiotropic meta-analyses of longitudinal studies discover novel genetic variants associated with age-related diseases

    Directory of Open Access Journals (Sweden)

    Liang He

    2016-10-01

    Full Text Available Age-related diseases may result from shared biological mechanisms in intrinsic processes of aging. Genetic effects on age-related diseases are often modulated by environmental factors due to their little contribution to fitness or are mediated through certain endophenotypes. Identification of genetic variants with pleiotropic effects on both common complex diseases and endophenotypes may reveal potential conflicting evolutionary pressures and deliver new insights into shared genetic contribution to healthspan and lifespan. Here, we performed pleiotropic meta-analyses of genetic variants using five NIH-funded datasets by integrating univariate summary statistics for age-related diseases and endophenotypes. We investigated three groups of traits: (1 endophenotypes such as blood glucose, blood pressure, lipids, hematocrit, and body mass index, (2 time-to-event outcomes such as the age-at-onset of diabetes mellitus (DM, cancer, cardiovascular diseases (CVDs and neurodegenerative diseases (NDs, and (3 both combined. In addition to replicating previous findings, we identify seven novel genome-wide significant loci (<5e-08, out of which five are low-frequency variants. Specifically, from Group 2, we find rs7632505 on 3q21.1 in SEMA5B, rs460976 on 21q22.3 (1kb from TMPRSS2 and rs12420422 on 11q24.1 predominantly associated with a variety of CVDs, rs4905014 in ITPK1 associated with stroke and heart failure, rs7081476 on 10p12.1 in ANKRD26 associated with multiple diseases including DM, CVDs and NDs. From Group 3, we find rs8082812 on 18p11.22 and rs1869717 on 4q31.3 associated with both endophenotypes and CVDs. Our follow-up analyses show that rs7632505, rs4905014 and rs8082812 have age-dependent effects on coronary heart disease or stroke. Functional annotation suggests that most of these SNPs are within regulatory regions or DNase clusters and in linkage disequilibrium with expression quantitative trait loci, implying their potential regulatory

  13. Statistical methods for meta-analyses including information from studies without any events-add nothing to nothing and succeed nevertheless.

    Science.gov (United States)

    Kuss, O

    2015-03-30

    Meta-analyses with rare events, especially those that include studies with no event in one ('single-zero') or even both ('double-zero') treatment arms, are still a statistical challenge. In the case of double-zero studies, researchers in general delete these studies or use continuity corrections to avoid them. A number of arguments against both options has been given, and statistical methods that use the information from double-zero studies without using continuity corrections have been proposed. In this paper, we collect them and compare them by simulation. This simulation study tries to mirror real-life situations as completely as possible by deriving true underlying parameters from empirical data on actually performed meta-analyses. It is shown that for each of the commonly encountered effect estimators valid statistical methods are available that use the information from double-zero studies without using continuity corrections. Interestingly, all of them are truly random effects models, and so also the current standard method for very sparse data as recommended from the Cochrane collaboration, the Yusuf-Peto odds ratio, can be improved on. For actual analysis, we recommend to use beta-binomial regression methods to arrive at summary estimates for the odds ratio, the relative risk, or the risk difference. Methods that ignore information from double-zero studies or use continuity corrections should no longer be used. We illustrate the situation with an example where the original analysis ignores 35 double-zero studies, and a superior analysis discovers a clinically relevant advantage of off-pump surgery in coronary artery bypass grafting. Copyright © 2014 John Wiley & Sons, Ltd.

  14. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration

    DEFF Research Database (Denmark)

    Liberati, Alessandro; Altman, Douglas G; Tetzlaff, Jennifer

    2009-01-01

    for transparent reporting of a systematic review. In this Explanation and Elaboration document, we explain the meaning and rationale for each checklist item. For each item, we include an example of good reporting and, where possible, references to relevant empirical studies and methodological literature......Systematic reviews and meta-analyses are essential to summarize evidence relating to efficacy and safety of health care interventions accurately and reliably. The clarity and transparency of these reports, however, is not optimal. Poor reporting of systematic reviews diminishes their value...... to clinicians, policy makers, and other users. Since the development of the QUOROM (QUality Of Reporting Of Meta-analysis) Statement--a reporting guideline published in 1999--there have been several conceptual, methodological, and practical advances regarding the conduct and reporting of systematic reviews...

  15. Cochrane reviews compared with industry supported meta-analyses and other meta-analyses of the same drugs: systematic review

    DEFF Research Database (Denmark)

    Jørgensen, Anders W; Hilden, Jørgen; Gøtzsche, Peter C

    2006-01-01

    OBJECTIVE: To compare the methodological quality and conclusions in Cochrane reviews with those in industry supported meta-analyses and other meta-analyses of the same drugs. DESIGN: Systematic review comparing pairs of meta-analyses that studied the same two drugs in the same disease and were...... reviews had a meta-analysis that compared two drugs. Twenty four meta-analyses that matched the Cochrane reviews were found: eight were industry supported, nine had undeclared support, and seven had no support or were supported by non-industry sources. On a 0-7 scale, the median quality score was 7...... patients or studies. The seven industry supported reviews that had conclusions recommended the experimental drug without reservations, compared with none of the Cochrane reviews (P = 0.02), although the estimated treatment effect was similar on average (z = 0.46, P = 0.64). Reviews with undeclared support...

  16. The geometric increase in meta-analyses from China in the genomic era.

    Directory of Open Access Journals (Sweden)

    John P A Ioannidis

    Full Text Available Meta-analyses are increasingly popular. It is unknown whether this popularity is driven by specific countries and specific meta-analyses types. PubMed was used to identify meta-analyses since 1995 (last update 9/1/2012 and catalogue their types and country of origin. We focused more on meta-analyses from China (the current top producer of meta-analyses versus the USA (top producer until recently. The annual number of meta-analyses from China increased 40-fold between 2003 and 2011 versus 2.4-fold for the USA. The growth of Chinese meta-analyses was driven by genetics (110-fold increase in 2011 versus 2003. The HuGE Navigator identified 612 meta-analyses of genetic association studies published in 2012 from China versus only 109 from the USA. We compared in-depth 50 genetic association meta-analyses from China versus 50 from USA in 2012. Meta-analyses from China almost always used only literature-based data (92%, and focused on one or two genes (94% and variants (78% identified with candidate gene approaches (88%, while many USA meta-analyses used genome-wide approaches and raw data. Both groups usually concluded favorably for the presence of genetic associations (80% versus 74%, but nominal significance (P<0.05 typically sufficed in the China group. Meta-analyses from China typically neglected genome-wide data, and often included candidate gene studies published in Chinese-language journals. Overall, there is an impressive rise of meta-analyses from China, particularly on genetic associations. Since most claimed candidate gene associations are likely false-positives, there is an urgent global need to incorporate genome-wide data and state-of-the art statistical inferences to avoid a flood of false-positive genetic meta-analyses.

  17. The geometric increase in meta-analyses from China in the genomic era.

    Science.gov (United States)

    Ioannidis, John P A; Chang, Christine Q; Lam, Tram Kim; Schully, Sheri D; Khoury, Muin J

    2013-01-01

    Meta-analyses are increasingly popular. It is unknown whether this popularity is driven by specific countries and specific meta-analyses types. PubMed was used to identify meta-analyses since 1995 (last update 9/1/2012) and catalogue their types and country of origin. We focused more on meta-analyses from China (the current top producer of meta-analyses) versus the USA (top producer until recently). The annual number of meta-analyses from China increased 40-fold between 2003 and 2011 versus 2.4-fold for the USA. The growth of Chinese meta-analyses was driven by genetics (110-fold increase in 2011 versus 2003). The HuGE Navigator identified 612 meta-analyses of genetic association studies published in 2012 from China versus only 109 from the USA. We compared in-depth 50 genetic association meta-analyses from China versus 50 from USA in 2012. Meta-analyses from China almost always used only literature-based data (92%), and focused on one or two genes (94%) and variants (78%) identified with candidate gene approaches (88%), while many USA meta-analyses used genome-wide approaches and raw data. Both groups usually concluded favorably for the presence of genetic associations (80% versus 74%), but nominal significance (PChina group. Meta-analyses from China typically neglected genome-wide data, and often included candidate gene studies published in Chinese-language journals. Overall, there is an impressive rise of meta-analyses from China, particularly on genetic associations. Since most claimed candidate gene associations are likely false-positives, there is an urgent global need to incorporate genome-wide data and state-of-the art statistical inferences to avoid a flood of false-positive genetic meta-analyses.

  18. Neural bases of food perception: coordinate-based meta-analyses of neuroimaging studies in multiple modalities.

    Science.gov (United States)

    Huerta, Claudia I; Sarkar, Pooja R; Duong, Timothy Q; Laird, Angela R; Fox, Peter T

    2014-06-01

    The purpose of this study was to compare the results of the three food-cue paradigms most commonly used for functional neuroimaging studies to determine: i) commonalities and differences in the neural response patterns by paradigm and ii) the relative robustness and reliability of responses to each paradigm. Functional magnetic resonance imaging studies using standardized stereotactic coordinates to report brain responses to food cues were identified using online databases. Studies were grouped by food-cue modality as: i) tastes (8 studies); ii) odors (8 studies); and, iii) images (11 studies). Activation likelihood estimation was used to identify statistically reliable regional responses within each stimulation paradigm. Brain response distributions were distinctly different for the three stimulation modalities, corresponding to known differences in location of the respective primary and associative cortices. Visual stimulation induced the most robust and extensive responses. The left anterior insula was the only brain region reliably responding to all three stimulus categories. These findings suggest visual food-cue paradigm as promising candidate for imaging studies addressing the neural substrate of therapeutic interventions. Copyright © 2014 The Obesity Society.

  19. Genome-wide Meta-analyses of Breast, Ovarian and Prostate Cancer Association Studies Identify Multiple New Susceptibility Loci Shared by At Least Two Cancer Types

    Science.gov (United States)

    Kar, Siddhartha P.; Beesley, Jonathan; Al Olama, Ali Amin; Michailidou, Kyriaki; Tyrer, Jonathan; Kote-Jarai, ZSofia; Lawrenson, Kate; Lindstrom, Sara; Ramus, Susan J.; Thompson, Deborah J.; Kibel, Adam S.; Dansonka-Mieszkowska, Agnieszka; Michael, Agnieszka; Dieffenbach, Aida K.; Gentry-Maharaj, Aleksandra; Whittemore, Alice S.; Wolk, Alicja; Monteiro, Alvaro; Peixoto, Ana; Kierzek, Andrzej; Cox, Angela; Rudolph, Anja; Gonzalez-Neira, Anna; Wu, Anna H.; Lindblom, Annika; Swerdlow, Anthony; Ziogas, Argyrios; Ekici, Arif B.; Burwinkel, Barbara; Karlan, Beth Y.; Nordestgaard, Børge G.; Blomqvist, Carl; Phelan, Catherine; McLean, Catriona; Pearce, Celeste Leigh; Vachon, Celine; Cybulski, Cezary; Slavov, Chavdar; Stegmaier, Christa; Maier, Christiane; Ambrosone, Christine B.; Høgdall, Claus K.; Teerlink, Craig C.; Kang, Daehee; Tessier, Daniel C.; Schaid, Daniel J.; Stram, Daniel O.; Cramer, Daniel W.; Neal, David E.; Eccles, Diana; Flesch-Janys, Dieter; Velez Edwards, Digna R.; Wokozorczyk, Dominika; Levine, Douglas A.; Yannoukakos, Drakoulis; Sawyer, Elinor J.; Bandera, Elisa V.; Poole, Elizabeth M.; Goode, Ellen L.; Khusnutdinova, Elza; Høgdall, Estrid; Song, Fengju; Bruinsma, Fiona; Heitz, Florian; Modugno, Francesmary; Hamdy, Freddie C.; Wiklund, Fredrik; Giles, Graham G.; Olsson, Håkan; Wildiers, Hans; Ulmer, Hans-Ulrich; Pandha, Hardev; Risch, Harvey A.; Darabi, Hatef; Salvesen, Helga B.; Nevanlinna, Heli; Gronberg, Henrik; Brenner, Hermann; Brauch, Hiltrud; Anton-Culver, Hoda; Song, Honglin; Lim, Hui-Yi; McNeish, Iain; Campbell, Ian; Vergote, Ignace; Gronwald, Jacek; Lubiński, Jan; Stanford, Janet L.; Benítez, Javier; Doherty, Jennifer A.; Permuth, Jennifer B.; Chang-Claude, Jenny; Donovan, Jenny L.; Dennis, Joe; Schildkraut, Joellen M.; Schleutker, Johanna; Hopper, John L.; Kupryjanczyk, Jolanta; Park, Jong Y.; Figueroa, Jonine; Clements, Judith A.; Knight, Julia A.; Peto, Julian; Cunningham, Julie M.; Pow-Sang, Julio; Batra, Jyotsna; Czene, Kamila; Lu, Karen H.; Herkommer, Kathleen; Khaw, Kay-Tee; Matsuo, Keitaro; Muir, Kenneth; Offitt, Kenneth; Chen, Kexin; Moysich, Kirsten B.; Aittomäki, Kristiina; Odunsi, Kunle; Kiemeney, Lambertus A.; Massuger, Leon F.A.G.; Fitzgerald, Liesel M.; Cook, Linda S.; Cannon-Albright, Lisa; Hooning, Maartje J.; Pike, Malcolm C.; Bolla, Manjeet K.; Luedeke, Manuel; Teixeira, Manuel R.; Goodman, Marc T.; Schmidt, Marjanka K.; Riggan, Marjorie; Aly, Markus; Rossing, Mary Anne; Beckmann, Matthias W.; Moisse, Matthieu; Sanderson, Maureen; Southey, Melissa C.; Jones, Michael; Lush, Michael; Hildebrandt, Michelle A. T.; Hou, Ming-Feng; Schoemaker, Minouk J.; Garcia-Closas, Montserrat; Bogdanova, Natalia; Rahman, Nazneen; Le, Nhu D.; Orr, Nick; Wentzensen, Nicolas; Pashayan, Nora; Peterlongo, Paolo; Guénel, Pascal; Brennan, Paul; Paulo, Paula; Webb, Penelope M.; Broberg, Per; Fasching, Peter A.; Devilee, Peter; Wang, Qin; Cai, Qiuyin; Li, Qiyuan; Kaneva, Radka; Butzow, Ralf; Kopperud, Reidun Kristin; Schmutzler, Rita K.; Stephenson, Robert A.; MacInnis, Robert J.; Hoover, Robert N.; Winqvist, Robert; Ness, Roberta; Milne, Roger L.; Travis, Ruth C.; Benlloch, Sara; Olson, Sara H.; McDonnell, Shannon K.; Tworoger, Shelley S.; Maia, Sofia; Berndt, Sonja; Lee, Soo Chin; Teo, Soo-Hwang; Thibodeau, Stephen N.; Bojesen, Stig E.; Gapstur, Susan M.; Kjær, Susanne Krüger; Pejovic, Tanja; Tammela, Teuvo L.J.; Dörk, Thilo; Brüning, Thomas; Wahlfors, Tiina; Key, Tim J.; Edwards, Todd L.; Menon, Usha; Hamann, Ute; Mitev, Vanio; Kosma, Veli-Matti; Setiawan, Veronica Wendy; Kristensen, Vessela; Arndt, Volker; Vogel, Walther; Zheng, Wei; Sieh, Weiva; Blot, William J.; Kluzniak, Wojciech; Shu, Xiao-Ou; Gao, Yu-Tang; Schumacher, Fredrick; Freedman, Matthew L.; Berchuck, Andrew; Dunning, Alison M.; Simard, Jacques; Haiman, Christopher A.; Spurdle, Amanda; Sellers, Thomas A.; Hunter, David J.; Henderson, Brian E.; Kraft, Peter; Chanock, Stephen J.; Couch, Fergus J.; Hall, Per; Gayther, Simon A.; Easton, Douglas F.; Chenevix-Trench, Georgia; Eeles, Rosalind; Pharoah, Paul D.P.; Lambrechts, Diether

    2016-01-01

    Breast, ovarian, and prostate cancers are hormone-related and may have a shared genetic basis but this has not been investigated systematically by genome-wide association (GWA) studies. Meta-analyses combining the largest GWA meta-analysis data sets for these cancers totaling 112,349 cases and 116,421 controls of European ancestry, all together and in pairs, identified at P < 10−8 seven new cross-cancer loci: three associated with susceptibility to all three cancers (rs17041869/2q13/BCL2L11; rs7937840/11q12/INCENP; rs1469713/19p13/GATAD2A), two breast and ovarian cancer risk loci (rs200182588/9q31/SMC2; rs8037137/15q26/RCCD1), and two breast and prostate cancer risk loci (rs5013329/1p34/NSUN4; rs9375701/6q23/L3MBTL3). Index variants in five additional regions previously associated with only one cancer also showed clear association with a second cancer type. Cell-type specific expression quantitative trait locus and enhancer-gene interaction annotations suggested target genes with potential cross-cancer roles at the new loci. Pathway analysis revealed significant enrichment of death receptor signaling genes near loci with P < 10−5 in the three-cancer meta-analysis. PMID:27432226

  20. Meta-analyses of genome-wide association studies identify multiple novel loci associated with pulmonary function

    Science.gov (United States)

    Hancock, Dana B.; Eijgelsheim, Mark; Wilk, Jemma B.; Gharib, Sina A.; Loehr, Laura R.; Marciante, Kristin D.; Franceschini, Nora; van Durme, Yannick M.T.A.; Chen, Ting-hsu; Barr, R. Graham; Schabath, Matthew B.; Couper, David J.; Brusselle, Guy G.; Psaty, Bruce M.; van Duijn, Cornelia M.; Rotter, Jerome I.; Uitterlinden, André G.; Hofman, Albert; Punjabi, Naresh M.; Rivadeneira, Fernando; Morrison, Alanna C.; Enright, Paul L.; North, Kari E.; Heckbert, Susan R.; Lumley, Thomas; Stricker, Bruno H.Ch.; O’Connor, George T.; London, Stephanie J.

    2010-01-01

    Measurements of lung function by spirometry are heritable traits that reflect respiratory health and predict morbidity and mortality. We meta-analyzed genome-wide association studies for two clinically important measures, forced expiratory volume in the first second (FEV1) and its ratio to forced vital capacity (FEV1/FVC), an indicator of airflow obstruction. This meta-analysis included 20,890 participants of European ancestry from four CHARGE consortium studies: Atherosclerosis Risk in Communities (ARIC), Cardiovascular Health Study (CHS), Framingham Heart Study (FHS), and Rotterdam Study (RS). We identified eight loci associated with FEV1/FVC (HHIP, GPR126, ADAM19, AGER-PPT2, FAM13A, PTCH1, PID1, and HTR4) and one locus associated with FEV1 (INTS12-GSTCD-NPNT) at or near genome-wide significance (PPID1) replicated with the SpiroMeta consortium. Our findings of novel loci influencing pulmonary function may offer insights into chronic lung disease pathogenesis. PMID:20010835

  1. The Association between Nocturia and Nocturnal Polyuria in Clinical and Epidemiological Studies : A Systematic Review and Meta-Analyses

    NARCIS (Netherlands)

    Hofmeester, Ilse; Kollen, Boudewijn J.; Steffens, Martijn G.; Bosch, J. L. H. Ruud; Drake, Marcus J.; Weiss, Jeffrey P.; Blanker, Marco H.

    Purpose: We determined the relationship between nocturia and nocturnal polyuria. Materials and Methods: The PubMed (R) and Embase (R) databases were searched for studies written in English, German, French or Dutch with original data on adult participants in an investigation of the relationship

  2. Comprehensive review of genetic association studies and meta-analyses on miRNA polymorphisms and cancer risk.

    Directory of Open Access Journals (Sweden)

    Kshitij Srivastava

    Full Text Available BACKGROUND: MicroRNAs (miRNAs are small RNA molecules that regulate the expression of corresponding messenger RNAs (mRNAs. Variations in the level of expression of distinct miRNAs have been observed in the genesis, progression and prognosis of multiple human malignancies. The present study was aimed to investigate the association between four highly studied miRNA polymorphisms (mir-146a rs2910164, mir-196a2 rs11614913, mir-149 rs2292832 and mir-499 rs3746444 and cancer risk by using a two-sided meta-analytic approach. METHODS: An updated meta-analysis based on 53 independent case-control studies consisting of 27573 cancer cases and 34791 controls was performed. Odds ratio (OR and 95% confidence interval (95% CI were used to investigate the strength of the association. RESULTS: Overall, the pooled analysis showed that mir-196a2 rs11614913 was associated with a decreased cancer risk (OR = 0.846, P = 0.004, TT vs. CC while other miRNA SNPs showed no association with overall cancer risk. Subgroup analyses based on type of cancer and ethnicity were also performed, and results indicated that there was a strong association between miR-146a rs2910164 and overall cancer risk in Caucasian population under recessive model (OR = 1.274, 95%CI = 1.096-1.481, P = 0.002. Stratified analysis by cancer type also associated mir-196a2 rs11614913 with lung and colorectal cancer at allelic and genotypic level. CONCLUSIONS: The present meta-analysis suggests an important role of mir-196a2 rs11614913 polymorphism with overall cancer risk especially in Asian population. Further studies with large sample size are needed to evaluate and confirm this association.

  3. Large-Scale Genome-Wide Association Studies and Meta-Analyses of Longitudinal Change in Adult Lung Function

    Science.gov (United States)

    Tang, Wenbo; Kowgier, Matthew; Loth, Daan W.; Soler Artigas, María; Joubert, Bonnie R.; Hodge, Emily; Gharib, Sina A.; Smith, Albert V.; Ruczinski, Ingo; Gudnason, Vilmundur; Mathias, Rasika A.; Harris, Tamara B.; Hansel, Nadia N.; Launer, Lenore J.; Barnes, Kathleen C.; Hansen, Joyanna G.; Albrecht, Eva; Aldrich, Melinda C.; Allerhand, Michael; Barr, R. Graham; Brusselle, Guy G.; Couper, David J.; Curjuric, Ivan; Davies, Gail; Deary, Ian J.; Dupuis, Josée; Fall, Tove; Foy, Millennia; Franceschini, Nora; Gao, Wei; Gläser, Sven; Gu, Xiangjun; Hancock, Dana B.; Heinrich, Joachim; Hofman, Albert; Imboden, Medea; Ingelsson, Erik; James, Alan; Karrasch, Stefan; Koch, Beate; Kritchevsky, Stephen B.; Kumar, Ashish; Lahousse, Lies; Li, Guo; Lind, Lars; Lindgren, Cecilia; Liu, Yongmei; Lohman, Kurt; Lumley, Thomas; McArdle, Wendy L.; Meibohm, Bernd; Morris, Andrew P.; Morrison, Alanna C.; Musk, Bill; North, Kari E.; Palmer, Lyle J.; Probst-Hensch, Nicole M.; Psaty, Bruce M.; Rivadeneira, Fernando; Rotter, Jerome I.; Schulz, Holger; Smith, Lewis J.; Sood, Akshay; Starr, John M.; Strachan, David P.; Teumer, Alexander; Uitterlinden, André G.; Völzke, Henry; Voorman, Arend; Wain, Louise V.; Wells, Martin T.; Wilk, Jemma B.; Williams, O. Dale; Heckbert, Susan R.; Stricker, Bruno H.; London, Stephanie J.; Fornage, Myriam; Tobin, Martin D.; O′Connor, George T.; Hall, Ian P.; Cassano, Patricia A.

    2014-01-01

    Background Genome-wide association studies (GWAS) have identified numerous loci influencing cross-sectional lung function, but less is known about genes influencing longitudinal change in lung function. Methods We performed GWAS of the rate of change in forced expiratory volume in the first second (FEV1) in 14 longitudinal, population-based cohort studies comprising 27,249 adults of European ancestry using linear mixed effects model and combined cohort-specific results using fixed effect meta-analysis to identify novel genetic loci associated with longitudinal change in lung function. Gene expression analyses were subsequently performed for identified genetic loci. As a secondary aim, we estimated the mean rate of decline in FEV1 by smoking pattern, irrespective of genotypes, across these 14 studies using meta-analysis. Results The overall meta-analysis produced suggestive evidence for association at the novel IL16/STARD5/TMC3 locus on chromosome 15 (P  =  5.71 × 10-7). In addition, meta-analysis using the five cohorts with ≥3 FEV1 measurements per participant identified the novel ME3 locus on chromosome 11 (P  =  2.18 × 10-8) at genome-wide significance. Neither locus was associated with FEV1 decline in two additional cohort studies. We confirmed gene expression of IL16, STARD5, and ME3 in multiple lung tissues. Publicly available microarray data confirmed differential expression of all three genes in lung samples from COPD patients compared with controls. Irrespective of genotypes, the combined estimate for FEV1 decline was 26.9, 29.2 and 35.7 mL/year in never, former, and persistent smokers, respectively. Conclusions In this large-scale GWAS, we identified two novel genetic loci in association with the rate of change in FEV1 that harbor candidate genes with biologically plausible functional links to lung function. PMID:24983941

  4. Large-scale genome-wide association studies and meta-analyses of longitudinal change in adult lung function.

    Directory of Open Access Journals (Sweden)

    Wenbo Tang

    Full Text Available Genome-wide association studies (GWAS have identified numerous loci influencing cross-sectional lung function, but less is known about genes influencing longitudinal change in lung function.We performed GWAS of the rate of change in forced expiratory volume in the first second (FEV1 in 14 longitudinal, population-based cohort studies comprising 27,249 adults of European ancestry using linear mixed effects model and combined cohort-specific results using fixed effect meta-analysis to identify novel genetic loci associated with longitudinal change in lung function. Gene expression analyses were subsequently performed for identified genetic loci. As a secondary aim, we estimated the mean rate of decline in FEV1 by smoking pattern, irrespective of genotypes, across these 14 studies using meta-analysis.The overall meta-analysis produced suggestive evidence for association at the novel IL16/STARD5/TMC3 locus on chromosome 15 (P  =  5.71 × 10(-7. In addition, meta-analysis using the five cohorts with ≥3 FEV1 measurements per participant identified the novel ME3 locus on chromosome 11 (P  =  2.18 × 10(-8 at genome-wide significance. Neither locus was associated with FEV1 decline in two additional cohort studies. We confirmed gene expression of IL16, STARD5, and ME3 in multiple lung tissues. Publicly available microarray data confirmed differential expression of all three genes in lung samples from COPD patients compared with controls. Irrespective of genotypes, the combined estimate for FEV1 decline was 26.9, 29.2 and 35.7 mL/year in never, former, and persistent smokers, respectively.In this large-scale GWAS, we identified two novel genetic loci in association with the rate of change in FEV1 that harbor candidate genes with biologically plausible functional links to lung function.

  5. A critical update on endothelial nitric oxide synthase gene variations in women with idiopathic recurrent spontaneous abortion: genetic association study, systematic review and meta-analyses.

    Science.gov (United States)

    Pereza, N; Peterlin, B; Volk, M; Kapović, M; Ostojić, S

    2015-05-01

    A number of case-control studies investigated the association between idiopathic recurrent spontaneous abortion (IRSA) and variations in the gene encoding endothelial nitric oxide synthase (NOS3), but yielded contradictory results. Our aim was to test the association of the NOS3 variable number of tandem repeats (VNTR) in intron 4 and +894 G/T single-nucleotide polymorphism (SNP) with IRSA in Slovenian women (148 IRSA and 149 control women), conduct a systematic review of literature on the association between NOS3 gene variations and IRSA, and perform meta-analyses of studies that met the inclusion criteria, defined by virtue of the European Society for Human Reproduction and Embryology evidence-based guidelines for recurrent spontaneous abortion. Genotyping was performed using PCR and restriction fragment length polymorphism methods. The systematic review of literature (English language) was conducted using PubMed and Scopus databases, to 1 November 2014. We determined no association of IRSA with the VNTR in intron 4 and +894 G/T SNP in Slovenian women. Furthermore, 16 case-control studies were identified on the association between 15 NOS3 gene variations and IRSA. However, significant inconsistencies exist in the selection criteria of patients and controls between studies. The meta-analysis of VNTR in intron 4 was performed on five studies (894 patients, 944 controls), whereas the meta-analysis of +894 G/T SNP included six studies (1111 patients, 1121 controls). The association with IRSA was significant for the +894 G/T SNP under the dominant genetic model (GT+TT versus GG) based on fixed (odds ratio (OR) = 1.54, 95% confidence interval (CI) = 1.28-1.86, P = NOS3 +894 G/T gene variation to IRSA. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Socioeconomic position, lifestyle factors and age at natural menopause: a systematic review and meta-analyses of studies across six continents

    Science.gov (United States)

    Schoenaker, Danielle AJM; Jackson, Caroline A; Rowlands, Jemma V; Mishra, Gita D

    2014-01-01

    Background: Age at natural menopause (ANM) is considered a marker of biological ageing and is increasingly recognized as a sentinel for chronic disease risk in later life. Socioeconomic position (SEP) and lifestyle factors are thought to be associated with ANM. Methods: We performed a systematic review and meta-analyses to determine the overall mean ANM, and the effect of SEP and lifestyle factors on ANM by calculating the weighted mean difference (WMD) and pooling adjusted hazard ratios. We explored heterogeneity using meta-regression and also included unpublished findings from the Australian Longitudinal Study on Women’s Health. Results: We identified 46 studies across 24 countries. Mean ANM was 48.8 years [95% confidence interval (CI): 48.3, 49.2], with between-study heterogeneity partly explained by geographical region. ANM was lowest among African, Latin American, Asian and Middle Eastern countries and highest in Europe and Australia, followed by the USA. Education was associated with later ANM (WMD middle vs low education 0.30, 95% CI: 0.10, 0.51; high vs low education 0.64, 95% CI 0.26, 1.02). A similar dose-response relationship was also observed for occupation. Smoking was associated with a 1-year reduction of ANM (WMD: -0.91, 95% CI: –1.34, –0.48). Being overweight and moderate/high physical activity were modestly associated with later ANM, but findings were less conclusive. Conclusions: ANM varies across populations, partly due to differences across geographical regions. SEP and some lifestyle factors are associated with ANM, but further research is needed to examine the impact of the associations between risk factors and ANM on future health outcomes. PMID:24771324

  7. Publication bias in dermatology systematic reviews and meta-analyses.

    Science.gov (United States)

    Atakpo, Paul; Vassar, Matt

    2016-05-01

    Systematic reviews and meta-analyses in dermatology provide high-level evidence for clinicians and policy makers that influence clinical decision making and treatment guidelines. One methodological problem with systematic reviews is the under representation of unpublished studies. This problem is due in part to publication bias. Omission of statistically non-significant data from meta-analyses may result in overestimation of treatment effect sizes which may lead to clinical consequences. Our goal was to assess whether systematic reviewers in dermatology evaluate and report publication bias. Further, we wanted to conduct our own evaluation of publication bias on meta-analyses that failed to do so. Our study considered systematic reviews and meta-analyses from ten dermatology journals from 2006 to 2016. A PubMed search was conducted, and all full-text articles that met our inclusion criteria were retrieved and coded by the primary author. 293 articles were included in our analysis. Additionally, we formally evaluated publication bias in meta-analyses that failed to do so using trim and fill and cumulative meta-analysis by precision methods. Publication bias was mentioned in 107 articles (36.5%) and was formally evaluated in 64 articles (21.8%). Visual inspection of a funnel plot was the most common method of evaluating publication bias. Publication bias was present in 45 articles (15.3%), not present in 57 articles (19.5%) and not determined in 191 articles (65.2%). Using the trim and fill method, 7 meta-analyses (33.33%) showed evidence of publication bias. Although the trim and fill method only found evidence of publication bias in 7 meta-analyses, the cumulative meta-analysis by precision method found evidence of publication bias in 15 meta-analyses (71.4%). Many of the reviews in our study did not mention or evaluate publication bias. Further, of the 42 articles that stated following PRISMA reporting guidelines, 19 (45.2%) evaluated for publication bias. In

  8. Random error in cardiovascular meta-analyses

    DEFF Research Database (Denmark)

    Albalawi, Zaina; McAlister, Finlay A; Thorlund, Kristian;

    2013-01-01

    BACKGROUND: Cochrane reviews are viewed as the gold standard in meta-analyses given their efforts to identify and limit systematic error which could cause spurious conclusions. The potential for random error to cause spurious conclusions in meta-analyses is less well appreciated. METHODS: We...... examined all reviews approved and published by the Cochrane Heart Group in the 2012 Cochrane Library that included at least one meta-analysis with 5 or more randomized trials. We used trial sequential analysis to classify statistically significant meta-analyses as true positives if their pooled sample size...... but infrequently recognized, even among methodologically robust reviews published by the Cochrane Heart Group. Meta-analysts and readers should incorporate trial sequential analysis when interpreting results....

  9. How Can Meta-Analyses Guide Practice? A Review of the Learning Disability Research Base

    Science.gov (United States)

    Therrien, William J.; Zaman, Maliha; Banda, Devender R.

    2011-01-01

    Meta-analysis is considered an acceptable method to evaluate research studies for evidence-based practices. The purpose of this review is to examine the applicability of using meta-analyses in the learning disability field to guide classroom practice. The authors evaluated 15 learning disability meta-analyses in three domains: large-scale…

  10. A Review of Meta-Analyses in Education: Methodological Strengths and Weaknesses

    Science.gov (United States)

    Ahn, Soyeon; Ames, Allison J.; Myers, Nicholas D.

    2012-01-01

    The current review addresses the validity of published meta-analyses in education that determines the credibility and generalizability of study findings using a total of 56 meta-analyses published in education in the 2000s. Our objectives were to evaluate the current meta-analytic practices in education, identify methodological strengths and…

  11. How individual participant data meta-analyses have influenced trial design, conduct, and analysis

    NARCIS (Netherlands)

    Tierney, J.F.; Pignon, J.P.; Gueffyier, F.; Clarke, M.; Askie, L.; Vale, C.L.; Burdett, S.; Rovers, M.M.

    2015-01-01

    OBJECTIVES: To demonstrate how individual participant data (IPD) meta-analyses have impacted directly on the design and conduct of trials and highlight other advantages IPD might offer. STUDY DESIGN AND SETTING: Potential examples of the impact of IPD meta-analyses on trials were identified at an in

  12. Association of study quality with completeness of reporting: have completeness of reporting and quality of systematic reviews and meta-analyses in major radiology journals changed since publication of the PRISMA statement?

    Science.gov (United States)

    Tunis, Adam S; McInnes, Matthew D F; Hanna, Ramez; Esmail, Kaisra

    2013-11-01

    To evaluate whether completeness of reporting of systematic reviews and meta-analyses in major radiology journals has changed since publication of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement; a secondary objective is to evaluate whether completeness of reporting (ie, PRISMA) is associated with study quality (ie, Assessing the Methodological Quality of Systematic Reviews [AMSTAR]). Systematic reviews and meta-analyses published in major radiology journals between January 2007 and December 2011 were identified by searching MEDLINE with the modified Montori method. Studies were reviewed independently by two investigators and assessed for adherence to the AMSTAR and PRISMA checklists. The average results were analyzed to assess for change in mean score before and after PRISMA publication and to assess results over time; a Pearson correlation coefficient was calculated to assess for any association between PRISMA and AMSTAR results. Included were 130 studies from 11 journals. Average PRISMA and AMSTAR results were 21.8 of 27 and 7.2 of 11, respectively. The average result was higher after publication of PRISMA, and PRISMA-reported items were 22.6 of 27 after publication of PRISMA versus 20.9 of 27 before publication of PRISMA; AMSTAR results were 7.7 of 11 after publication of PRISMA versus 6.7 of 11 before publication of PRISMA. There was a strong positive correlation (r = 0.86) between the PRISMA and AMSTAR results. There was high variability between journals. Radiology had the highest PRISMA reported items (24.7 of 27), and American Journal of Neuroradiology had the lowest (19.6 of 27). Two major areas for improvement include study protocol registration and assessment of risk of bias across studies (ie, publication bias). In major radiology journal studies, there was modest improvement in completeness of reporting of systematic reviews and meta-analyses, assessed by PRISMA, which was strongly associated with higher study

  13. Meta-analyses on viral hepatitis

    DEFF Research Database (Denmark)

    Gluud, Lise L; Gluud, Christian

    2009-01-01

    This article summarizes the meta-analyses of interventions for viral hepatitis A, B, and C. Some of the interventions assessed are described in small trials with unclear bias control. Other interventions are supported by large, high-quality trials. Although attempts have been made to adjust...

  14. The strengths and limitations of meta-analyses based on aggregate data

    Directory of Open Access Journals (Sweden)

    Kuderer Nicole M

    2005-04-01

    Full Text Available Abstract Background Properly performed systematic reviews and meta-analyses are thought by many to represent among the highest level of evidence addressing important clinical issues. Few would disagree that meta-analyses based on individual patient data (IPD offer several advantages and represent the standard to which all other systematic reviews should be compared. Methods All cancer-related meta-analyses cited in Medline were classified as based on aggregate or individual patient data. A review was then undertaken of all reports comparing the comparative strengths and limitations of meta-analyses using either aggregate or individual patient data. Results The majority of published meta-analyses are based on summary or aggregate patient data (APD. Reasons suggested for this include the considerable resources, years of study and often, broad international cooperation required for IPD meta-analyses. Many of the most important features of systematic reviews including formal meta-analyses are addressed by both IPD and APD meta-analyses. The need for defining an explicit and relevant clinical question, exhaustively searching for the totality of evidence, meticulous and unbiased data transfer or extraction, assessment of between study heterogeneity and the use of appropriate statistical methods for estimating summary effect measures are essentially the same for the two approaches. Conclusion IPD offers advantages and, when feasible, should be considered the best opportunity to summarize the results of multiple studies. However, the resources, time and cooperation required for such studies will continue to limit their use in many important areas of clinical medicine which can be meaningfully and cost-effectively approached by properly performed APD meta-analyses. APD meta-analyses continue to be the mainstay of systematic reviews utilized by the US Preventive Services Task Force, the Cochrane Collaboration and many professional societies to support

  15. A systematic evaluation of the quality of meta-analyses in endodontics.

    Science.gov (United States)

    Suebnukarn, Siriwan; Ngamboonsirisingh, Sureeporn; Rattanabanlang, Angwara

    2010-04-01

    Meta-analyses have been suggested to be the highest form of evidence available to clinicians to guide clinical practice in dental care. High methodologic quality is a prerequisite for valid interpretation and application of review findings. However, meta-analyses are complex exercises, and assessing quality can be a daunting task. Clinicians and policymakers require guidance, which is not provided adequately by the available literature on the quality of meta-analyses. The purpose of this study was to systematically evaluate the quality of meta-analyses that address topics pertinent to endodontics. To identify potentially eligible meta-analyses for inclusion, systematic searches performed in MEDLINE and the Cochrane Database of Systematic Reviews were enriched by hand searches, citation mining, and expert recommendation. Comprehensive search strategies were constructed for electronic searches. Predetermined inclusion criteria were applied to each identified meta-analysis independently by two reviewers. To assess report quality, the included meta-analyses were assessed by using A Measurement Tool to Assess Systematic Reviews (AMSTAR). A total of 16 reports of meta-analyses were included (kappa = 0.96). The overall quality of reports of meta-analyses was found to be high, with an estimated mean overall AMSTAR score of 8.33 out of 11 (95% confidence interval, 7.62-8.88). The weakest areas within the included meta-analyses were failure to report the likelihood of publication bias. The overall quality of the reports of meta-analyses available in endodontics is high according to AMSTAR. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. 中文期刊发表的肾脏病学Meta分析的规范性研究%A standardization study of Meta-analyses on nephropathy published in Chinese journals

    Institute of Scientific and Technical Information of China (English)

    刘金彦; 赵宇亮; 周清华; 吴玉梅; 周生国; 张凌; 付平

    2013-01-01

    目的 评价中文期刊发表的肾脏病学领域Meta分析类报告的规范性.方法 检索万方数据库、中国知网、维普数据库、中国生物医学文献数据库(CBM)和相关杂志中符合纳入标准的Meta分析类研究,使用国际公认的PRISMA(Preferred Reporting Items for Systematic Reviews and MetaAnalyses)声明和MOOSE(Meta-analysis of Observational Studies in Epidemiology)规范对纳入的Meta分析进行逐条评价.结果 共纳入217篇肾脏病学领域的中文Meta分析类报告.原始研究为随机对照试验(RCT)的Meta分析166篇,根据QUOROM声明,51.8%(86篇)在前言部分提出了完整的研究假说,13.9%(23篇)绘制了文献筛选流程图,15.7%(26篇)进行了亚组分析,53.0%(88篇)实施了发表偏倚分析,28.3%(47篇)进行了敏感性分析.原始研究为观察性研究的Meta分析共51篇,根据MOOSE规范,仅9.8%(5篇)计算了统计学稳定性指标,54.9%(28篇)介绍了结论的应用前景,45.1%(23篇)讨论了研究局限性,2.0%(1篇)进行了偏倚的定量讨论,17.6%(9篇)展望了未来研究方向.结论 中文期刊发表的肾脏病学领域Meta分析类论著普遍存在假说交代不清、过程透明度低、异质性和偏倚分析不深入等问题,格式规范性有待加强.%Objective To evaluate the standardization of Meta-analyses on nephropathy published in Chinese journals.Methods By searching in WANFANG,VIP,CNKI databases and Chinese Biomedical Literature Database(CBM) as well as related Chinese journals,eligible Meta-analyses were enrolled and analyzed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Statement and the MOOSE (Meta-analysis of Observational Studies in Epidemiology) Checklist.Results A total of 217 Meta-analyses were enrolled with 166 on randomized controlled trials (RCT) and 51 on observational studies.Based on the PRSIMA Statement,of the 166 Meta-analyses on RCT,51.8%(86 papers) were found

  17. 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.

  18. Reporting quality in abstracts of meta-analyses of depression screening tool accuracy: a review of systematic reviews and meta-analyses

    Science.gov (United States)

    Rice, Danielle B; Kloda, Lorie A; Shrier, Ian; Thombs, Brett D

    2016-01-01

    Objective Concerns have been raised regarding the quality and completeness of abstract reporting in evidence reviews, but this had not been evaluated in meta-analyses of diagnostic accuracy. Our objective was to evaluate reporting quality and completeness in abstracts of systematic reviews with meta-analyses of depression screening tool accuracy, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) for Abstracts tool. Design Cross-sectional study. Inclusion Criteria We searched MEDLINE and PsycINFO from 1 January 2005 through 13 March 2016 for recent systematic reviews with meta-analyses in any language that compared a depression screening tool to a diagnosis based on clinical or validated diagnostic interview. Data extraction Two reviewers independently assessed quality and completeness of abstract reporting using the PRISMA for Abstracts tool with appropriate adaptations made for studies of diagnostic test accuracy. Bivariate associations of number of PRISMA for Abstracts items complied with (1) journal abstract word limit and (2) A Measurement Tool to Assess Systematic Reviews (AMSTAR) scores of meta-analyses were also assessed. Results We identified 21 eligible meta-analyses. Only two of 21 included meta-analyses complied with at least half of adapted PRISMA for Abstracts items. The majority met criteria for reporting an appropriate title (95%), result interpretation (95%) and synthesis of results (76%). Meta-analyses less consistently reported databases searched (43%), associated search dates (33%) and strengths and limitations of evidence (19%). Most meta-analyses did not adequately report a clinically meaningful description of outcomes (14%), risk of bias (14%), included study characteristics (10%), study eligibility criteria (5%), registration information (5%), clear objectives (0%), report eligibility criteria (0%) or funding (0%). Overall meta-analyses quality scores were significantly associated with the number of PRISMA

  19. Peroxisome proliferator-activated receptor gamma-2 P12A polymorphism and risk of acute myocardial infarction, coronary heart disease and ischemic stroke: A case-cohort study and meta-analyses

    Directory of Open Access Journals (Sweden)

    Mohammad Hadi Zafarmand

    2008-04-01

    Full Text Available Mohammad Hadi Zafarmand1,3, Yvonne T van der Schouw1, Diederick E Grobbee1, Peter W de Leeuw2, Michiel L Bots11Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Heidelberglaan 100, Str 6.131, 3584 CX, Utrecht, The Netherlands; 2Department of Internal Medicine, University Hospital Maastricht, PO Box 5800, NL-6202 AZ, Maastricht, The Netherlands; 3Persian Gulf Health Research Center, Department of Genomic Health, Bushehr University of Medical Sciences and Health Services, Moalem Street, Po Box 3631, Bushehr, IranBackground: The alanine allele of P12A polymorphism in PPARG gene in a few studies has been associated with a reduced or increased risk of acute myocardial infarction (AMI. Yet, the risk relation has not been confirmed, and data on ischemic stroke (IS is scarce. We therefore investigated the role of this polymorphism on occurrence of AMI, coronary heart disease (CHD and IS.Methods and findings: We performed a case-cohort study in 15,236 initially healthy Dutch women and applied a Cox proportional hazards model to study the relation of the P12A polymorphism and AMI (n = 71, CHD (n = 211, and IS (n = 49 under different inheritance models. In addition, meta-analyses of published studies were performed. Under the dominant inheritance model, carriers of the alanine allele compared with those with the more common genotype were not at increased or decreased risk of CHD (hazard ratio [HR] = 0.82; 95% confidence interval [CI], 0.58 to 1.17 and of IS (HR = 1.03; 95% CI, 0.14 to 7.74. In addition no relations were found under the recessive and additive models. Our meta-analyses corroborated these findings by showing no significant association. For AMI we found a borderline significant association under dominant (HR = 0.49; 95% CI, 0.26 to 0.94, and additive (HR = 0.51; 95% CI, 0.26 to 1.00 models which could be due to chance, because of small cases in this subgroup. The meta-analysis did not show any association

  20. Hyperhomocysteinemia, methylenetetrahydrofolate reductase c.677C>T polymorphism and risk of cancer: cross-sectional and prospective studies and meta-analyses of 75,000 cases and 93,000 controls

    DEFF Research Database (Denmark)

    Zacho, Jeppe; Yazdanyar, Shiva; Bojesen, Stig E

    2011-01-01

    and the association of the MTHFR c.677TC>T variant with hyperhomocysteinemia and with cancer. We performed a cross-sectional study of 5,949 Danish general population adults, a prospective study of 9,235 Danish general population adults with up to 60 years of registry surveillance, and meta-analyses of 231 studies...... including 74,671 cases and 93,344 controls. Cross-sectionally, plasma homocysteine levels were 12.9 and 11.6 μmol/L in those with and without cancer (p 12.4 versus ....4 μmol/L did not differ from 1.0. In cancer-free participants, plasma homocysteine levels were 14.7 and 11.7 μmol/L in MTHFR c.677C>T homozygtes and noncarriers (p T homozygotes versus noncarriers did not differ...

  1. Homeopathy: meta-analyses of pooled clinical data.

    Science.gov (United States)

    Hahn, Robert G

    2013-01-01

    In the first decade of the evidence-based era, which began in the mid-1990s, meta-analyses were used to scrutinize homeopathy for evidence of beneficial effects in medical conditions. In this review, meta-analyses including pooled data from placebo-controlled clinical trials of homeopathy and the aftermath in the form of debate articles were analyzed. In 1997 Klaus Linde and co-workers identified 89 clinical trials that showed an overall odds ratio of 2.45 in favor of homeopathy over placebo. There was a trend toward smaller benefit from studies of the highest quality, but the 10 trials with the highest Jadad score still showed homeopathy had a statistically significant effect. These results challenged academics to perform alternative analyses that, to demonstrate the lack of effect, relied on extensive exclusion of studies, often to the degree that conclusions were based on only 5-10% of the material, or on virtual data. The ultimate argument against homeopathy is the 'funnel plot' published by Aijing Shang's research group in 2005. However, the funnel plot is flawed when applied to a mixture of diseases, because studies with expected strong treatments effects are, for ethical reasons, powered lower than studies with expected weak or unclear treatment effects. To conclude that homeopathy lacks clinical effect, more than 90% of the available clinical trials had to be disregarded. Alternatively, flawed statistical methods had to be applied. Future meta-analyses should focus on the use of homeopathy in specific diseases or groups of diseases instead of pooling data from all clinical trials.

  2. Quality Assessment of Meta-analyses Published in Leading Anesthesiology Journals From 2005 to 2014.

    Science.gov (United States)

    Hall, Amber M; Lee, Sandra; Zurakowski, David

    2017-06-01

    Meta-analysis, when preceded by a systematic review, is considered the "gold standard" in data aggregation; however, the quality of meta-analyses is often questionable, leading to uncertainty about the accuracy of results. In this study, we evaluate the quality of meta-analyses published in 5 leading anesthesiology journals from 2005 to 2014. A total of 220 meta-analyses published in Anesthesiology, Pain, British Journal of Anaesthesia, Anaesthesia, or Anesthesia & Analgesia were identified for inclusion. The quality of each meta-analysis was determined using the Revised Assessment of Multiple Systematic Reviews (R-AMSTAR). R-AMSTAR rated 11 questions related to systematic reviews and meta-analyses on a scale of 1-4, with 4 representing the highest quality. Overall meta-analyses quality was evaluated using a Spearmen regression analysis and found to positively correlate with time (rs = 0.24, P leading anesthesiology journals has increased over the last decade. Furthermore, assessing the scientific quality of included studies in meta-analyses (P = .60) and using this assessment to formulate conclusions and/or recommendations (P = .67) remains relatively low (median R-AMSTAR: 2, interquartile range [IQR]: 2-3]; median R-AMSTAR: 2, IQR: 1-2, respectively).

  3. Meta-Analyses of Biosolids Effect in Dryland Wheat Agroecosystems.

    Science.gov (United States)

    Barbarick, Kenneth; Ippolito, James; McDaniel, Jacob

    2017-03-01

    Land application to cropping systems is USEPA's preferred method of recycling biosolids. Determination of biosolids effect size through meta-analyses from two decades of field-location research at three sites should answer the question: Does 20 yr of biosolids application affect dryland wheat ( L.) grain production, grain nutrient concentrations, and soil elemental extractability compared with equivalent rates of commercial N fertilizer? At two sites, biennial biosolids application rates to a wheat-fallow (WF) rotation were up to 11.2 dry Mg ha and up to 112 kg commercial N fertilizer ha, whereas rates at the third location varied to match soil-test information. Crop rotations included WF and wheat-corn ( L.)-fallow. We completed meta-analyses of biosolids effects compared with N fertilizer on wheat yield, grain protein, grain total, and soil ammonium bicarbonate-diethylenetriaminepentaacetic acid (ABDTPA)-extractable P, Zn, Cu, Fe, and Ni concentrations at the aforementioned sites from 1993 through 2013. Results showed that biosolids produced greater grain P and Zn at one site. Biosolids rates at two sites resulted in greater grain Zn and ABDTPA P, Zn, Cu, and Fe. Meta-analyses tests for heterogeneity indicated that the variance for all sites and rates could be explained as consistent across treatments, whereas the test for the 20 yr showed that heterogeneity was large and other factors affected the variance (e.g., climatic variability between years). Meta-analysis showed the practical effect of biosolids over a 20-yr study and demonstrated that the primary biosolids effect was an improvement in Zn availability to wheat. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Conclusive meta-analyses on antenatal magnesium may be inconclusive! Are we underestimating the risk of random error?

    DEFF Research Database (Denmark)

    Brok, Jesper; Huusom, Lene D; Thorlund, Kristian

    2012-01-01

    Results from meta-analyses significantly influence clinical practice. Both simulation and empirical studies have demonstrated that the risk of random error (i.e. spurious chance findings) in meta-analyses is much higher than previously anticipated. Hence, authors and users of systematic reviews a...

  5. Meta-analyses of RELN variants in neuropsychiatric disorders.

    Science.gov (United States)

    Chen, Na; Bao, Yanping; Xue, Yanxue; Sun, Yan; Hu, Die; Meng, Shiqiu; Lu, Lin; Shi, Jie

    2017-08-14

    Reelin is a critical extracellular matrix glycoprotein and implicated in neurodevelopment and psychiatric disorders in animal model studies. The genetic polymorphism of RELN has also been reported to be associated with several psychiatric disorders, but the results remain controversial. Here, we conducted meta-analyses of RELN gene SNPs and related neuropsychiatric disorders (schizophrenia, autistic spectrum disorders, attention-deficit hyperactivity disorder, Alzheimer's disease and bipolar disorders). A total of 12 SNPs (rs736707, rs362691, rs607755, rs2229864, rs7341475, rs262355, rs362719, rs11496125, g.-888G>C, rs2299356, rs528528, and rs4298437) in RELN gene were included into meta-analyses. Subgroup analyses based on ethnicity were performed. We found that RELN rs736707 was significantly related with psychiatric disorders (schizophrenia, autism spectrum disorders and attention-deficit hyperactivity disorder) in Asian group (C vs T, OR=1.26, 95% CI=1.13-1.41, P<0.01, FDR<0.01), and rs7341475 was only significantly associated with reduced risk of schizophrenia in Caucasian (A vs G, OR=0.88, 95% CI=0.82-0.95, P<0.01, FDR<0.01). No association of other SNPs and psychiatric disorders is found. These findings suggest a role of RELN SNPs in psychiatric diseases, and indicate that further researches in populations with different genetic background and studies with larger sample size are of great value. Copyright © 2017. Published by Elsevier B.V.

  6. Restricted versus Unrestricted Learning: Synthesis of Recent Meta-Analyses

    Science.gov (United States)

    Johnson, Genevieve

    2007-01-01

    Meta-analysis is a method of quantitatively summarizing the results of experimental research. This article summarizes four meta-analyses published since 2003 that compare the effect of DE and traditional education (TE) on student learning. Despite limitations, synthesis of these meta-analyses establish, at the very least, equivalent learning…

  7. The Role of the Amygdala in Facial Trustworthiness Processing: A Systematic Review and Meta-Analyses of fMRI Studies.

    Science.gov (United States)

    Santos, Sara; Almeida, Inês; Oliveiros, Bárbara; Castelo-Branco, Miguel

    2016-01-01

    Faces play a key role in signaling social cues such as signals of trustworthiness. Although several studies identify the amygdala as a core brain region in social cognition, quantitative approaches evaluating its role are scarce. This review aimed to assess the role of the amygdala in the processing of facial trustworthiness, by analyzing its amplitude BOLD response polarity to untrustworthy versus trustworthy facial signals under fMRI tasks through a Meta-analysis of effect sizes (MA). Activation Likelihood Estimation (ALE) analyses were also conducted. Articles were retrieved from MEDLINE, ScienceDirect and Web-of-Science in January 2016. Following the PRISMA statement guidelines, a systematic review of original research articles in English language using the search string "(face OR facial) AND (trustworthiness OR trustworthy OR untrustworthy OR trustee) AND fMRI" was conducted. The MA concerned amygdala responses to facial trustworthiness for the contrast Untrustworthy vs. trustworthy faces, and included whole-brain and ROI studies. To prevent potential bias, results were considered even when at the single study level they did not survive correction for multiple comparisons or provided non-significant results. ALE considered whole-brain studies, using the same methodology to prevent bias. A summary of the methodological options (design and analysis) described in the articles was finally used to get further insight into the characteristics of the studies and to perform a subgroup analysis. Data were extracted by two authors and checked independently. Twenty fMRI studies were considered for systematic review. An MA of effect sizes with 11 articles (12 studies) showed high heterogeneity between studies [Q(11) = 265.68, p trustworthiness. Six articles/studies showed that posterior cingulate and medial frontal gyrus present positive correlations with increasing facial trustworthiness levels. Significant effects considering subgroup analysis based on methodological

  8. Effect of excess iodine intake on thyroid diseases in different populations: A systematic review and meta-analyses including observational studies

    Science.gov (United States)

    Katagiri, Ryoko; Yuan, Xiaoyi; Kobayashi, Satomi; Sasaki, Satoshi

    2017-01-01

    Background Although several reports concerning the association of iodine excess and thyroid disease have appeared, no systematic review of the association between iodine excess intake and thyroid diseases, especially hyperthyroidism and hypothyroidism, has yet been reported. Method We conducted a systematic search of Ovid MEDLINE, PubMed, Cochrane Central Register of Controlled Trials databases, Ichushi-Web and CiNii database for intervention trials and observational studies. Search terms were constructed from related words for excess AND iodine intake or excretion AND thyroid hormones or diseases AND study designs. After considering the qualitative heterogeneity among studies, a meta-analysis was conducted and odds ratios and 95% confidence intervals (CI) were estimated in random-effects models. A protocol was registered with PROSPERO (No. CRD42015028081). Results 50 articles were included, including three intervention trials, six case-control studies, six follow-up studies and 35 cross-sectional studies. Three cross-sectional studies in adults included in meta-analysis. Odds ratio of overt and subclinical hypothyroidism between excess and adequate populations were 2.78 (CI:1.47 to 5.27) and 2.03 (CI:1.58 to 2.62) in adults, respectively. Source of excess iodine status was mainly iodized salt or water in included studies. Conclusion Although universal salt iodization has improved goiter rates, chronic exposure to excess iodine from water or poorly monitored salt are risk factors for hypothyroidism in free-living populations. Monitoring of both iodine concentration in salt as well as the iodine concentration in local drinking water are essential to preventing thyroid diseases. Hypothyroidism should be also carefully monitored in areas with excess iodine. Because of the low quality and limited number of included studies, further evidence and review are required. PMID:28282437

  9. Effect of excess iodine intake on thyroid diseases in different populations: A systematic review and meta-analyses including observational studies.

    Science.gov (United States)

    Katagiri, Ryoko; Yuan, Xiaoyi; Kobayashi, Satomi; Sasaki, Satoshi

    2017-01-01

    Although several reports concerning the association of iodine excess and thyroid disease have appeared, no systematic review of the association between iodine excess intake and thyroid diseases, especially hyperthyroidism and hypothyroidism, has yet been reported. We conducted a systematic search of Ovid MEDLINE, PubMed, Cochrane Central Register of Controlled Trials databases, Ichushi-Web and CiNii database for intervention trials and observational studies. Search terms were constructed from related words for excess AND iodine intake or excretion AND thyroid hormones or diseases AND study designs. After considering the qualitative heterogeneity among studies, a meta-analysis was conducted and odds ratios and 95% confidence intervals (CI) were estimated in random-effects models. A protocol was registered with PROSPERO (No. CRD42015028081). 50 articles were included, including three intervention trials, six case-control studies, six follow-up studies and 35 cross-sectional studies. Three cross-sectional studies in adults included in meta-analysis. Odds ratio of overt and subclinical hypothyroidism between excess and adequate populations were 2.78 (CI:1.47 to 5.27) and 2.03 (CI:1.58 to 2.62) in adults, respectively. Source of excess iodine status was mainly iodized salt or water in included studies. Although universal salt iodization has improved goiter rates, chronic exposure to excess iodine from water or poorly monitored salt are risk factors for hypothyroidism in free-living populations. Monitoring of both iodine concentration in salt as well as the iodine concentration in local drinking water are essential to preventing thyroid diseases. Hypothyroidism should be also carefully monitored in areas with excess iodine. Because of the low quality and limited number of included studies, further evidence and review are required.

  10. The Effect of Testing on Achievement: Meta-Analyses and Research Summary, 1910–2010. Source List, Effect Sizes, and References for Survey Studies

    Directory of Open Access Journals (Sweden)

    Richard P. Phelps

    2011-01-01

    Full Text Available The study summarizes the research literature on the effect of testing on student achievement, which comprises several hundred studies conducted from the early 20th century to the present day. Only survey studies, however, are included here (N studies = 247; N effects = 813; total respondent population . 700,000. Moreover, the surveys summarized here are limited to North America from the year 1958–2008. Surveys measure perceptions of effects—either through public opinion polls or surveys of groups selected within program evaluations. The mean effect size (for the perception that testing has a positive effect on achievement exceeds +1.0, a very large effect. Effect sizes are relatively weaker, however, for situations in which one group is held accountable for the performance of another—holding either teachers or schools accountable for student scores.

  11. PCSK9 R46L, low-density lipoprotein cholesterol levels, and risk of ischemic heart disease: 3 independent studies and meta-analyses

    DEFF Research Database (Denmark)

    Benn, Marianne; Nordestgaard, Børge G; Grande, Peer

    2010-01-01

    The aim of this study was to examine the effect of PCSK9 R46L on low-density lipoprotein cholesterol (LDL-C), risk of ischemic heart disease (IHD), and mortality.......The aim of this study was to examine the effect of PCSK9 R46L on low-density lipoprotein cholesterol (LDL-C), risk of ischemic heart disease (IHD), and mortality....

  12. The Role of the Amygdala in Facial Trustworthiness Processing: A Systematic Review and Meta-Analyses of fMRI Studies

    Science.gov (United States)

    Oliveiros, Bárbara

    2016-01-01

    Background Faces play a key role in signaling social cues such as signals of trustworthiness. Although several studies identify the amygdala as a core brain region in social cognition, quantitative approaches evaluating its role are scarce. Objectives This review aimed to assess the role of the amygdala in the processing of facial trustworthiness, by analyzing its amplitude BOLD response polarity to untrustworthy versus trustworthy facial signals under fMRI tasks through a Meta-analysis of effect sizes (MA). Activation Likelihood Estimation (ALE) analyses were also conducted. Data sources Articles were retrieved from MEDLINE, ScienceDirect and Web-of-Science in January 2016. Following the PRISMA statement guidelines, a systematic review of original research articles in English language using the search string “(face OR facial) AND (trustworthiness OR trustworthy OR untrustworthy OR trustee) AND fMRI” was conducted. Study selection and data extraction The MA concerned amygdala responses to facial trustworthiness for the contrast Untrustworthy vs. trustworthy faces, and included whole-brain and ROI studies. To prevent potential bias, results were considered even when at the single study level they did not survive correction for multiple comparisons or provided non-significant results. ALE considered whole-brain studies, using the same methodology to prevent bias. A summary of the methodological options (design and analysis) described in the articles was finally used to get further insight into the characteristics of the studies and to perform a subgroup analysis. Data were extracted by two authors and checked independently. Data synthesis Twenty fMRI studies were considered for systematic review. An MA of effect sizes with 11 articles (12 studies) showed high heterogeneity between studies [Q(11) = 265.68, p trustworthiness. Six articles/studies showed that posterior cingulate and medial frontal gyrus present positive correlations with increasing facial

  13. Routine antenatal anti-D prophylaxis in women who are Rh(D negative: meta-analyses adjusted for differences in study design and quality.

    Directory of Open Access Journals (Sweden)

    Rebecca M Turner

    Full Text Available BACKGROUND: To estimate the effectiveness of routine antenatal anti-D prophylaxis for preventing sensitisation in pregnant Rhesus negative women, and to explore whether this depends on the treatment regimen adopted. METHODS: Ten studies identified in a previous systematic literature search were included. Potential sources of bias were systematically identified using bias checklists, and their impact and uncertainty were quantified using expert opinion. Study results were adjusted for biases and combined, first in a random-effects meta-analysis and then in a random-effects meta-regression analysis. RESULTS: In a conventional meta-analysis, the pooled odds ratio for sensitisation was estimated as 0.25 (95% CI 0.18, 0.36, comparing routine antenatal anti-D prophylaxis to control, with some heterogeneity (I²  =  19%. However, this naïve analysis ignores substantial differences in study quality and design. After adjusting for these, the pooled odds ratio for sensitisation was estimated as 0.31 (95% CI 0.17, 0.56, with no evidence of heterogeneity (I²  =  0%. A meta-regression analysis was performed, which used the data available from the ten anti-D prophylaxis studies to inform us about the relative effectiveness of three licensed treatments. This gave an 83% probability that a dose of 1250 IU at 28 and 34 weeks is most effective and a 76% probability that a single dose of 1500 IU at 28-30 weeks is least effective. CONCLUSION: There is strong evidence for the effectiveness of routine antenatal anti-D prophylaxis for prevention of sensitisation, in support of the policy of offering routine prophylaxis to all non-sensitised pregnant Rhesus negative women. All three licensed dose regimens are expected to be effective.

  14. Does low-energy sweetener consumption affect energy intake and body weight? A systematic review, including meta-analyses, of the evidence from human and animal studies.

    Science.gov (United States)

    Rogers, P J; Hogenkamp, P S; de Graaf, C; Higgs, S; Lluch, A; Ness, A R; Penfold, C; Perry, R; Putz, P; Yeomans, M R; Mela, D J

    2016-03-01

    By reducing energy density, low-energy sweeteners (LES) might be expected to reduce energy intake (EI) and body weight (BW). To assess the totality of the evidence testing the null hypothesis that LES exposure (versus sugars or unsweetened alternatives) has no effect on EI or BW, we conducted a systematic review of relevant studies in animals and humans consuming LES with ad libitum access to food energy. In 62 of 90 animal studies exposure to LES did not affect or decreased BW. Of 28 reporting increased BW, 19 compared LES with glucose exposure using a specific 'learning' paradigm. Twelve prospective cohort studies in humans reported inconsistent associations between LES use and body mass index (-0.002 kg m(-)(2) per year, 95% confidence interval (CI) -0.009 to 0.005). Meta-analysis of short-term randomized controlled trials (129 comparisons) showed reduced total EI for LES versus sugar-sweetened food or beverage consumption before an ad libitum meal (-94 kcal, 95% CI -122 to -66), with no difference versus water (-2 kcal, 95% CI -30 to 26). This was consistent with EI results from sustained intervention randomized controlled trials (10 comparisons). Meta-analysis of sustained intervention randomized controlled trials (4 weeks to 40 months) showed that consumption of LES versus sugar led to relatively reduced BW (nine comparisons; -1.35 kg, 95% CI -2.28 to -0.42), and a similar relative reduction in BW versus water (three comparisons; -1.24 kg, 95% CI -2.22 to -0.26). Most animal studies did not mimic LES consumption by humans, and reverse causation may influence the results of prospective cohort studies. The preponderance of evidence from all human randomized controlled trials indicates that LES do not increase EI or BW, whether compared with caloric or non-caloric (for example, water) control conditions. Overall, the balance of evidence indicates that use of LES in place of sugar, in children and adults, leads to reduced EI and BW, and possibly also

  15. A semi-quantitative model of Quorum-Sensing in Staphylococcus aureus, approved by microarray meta-analyses and tested by mutation studies.

    Science.gov (United States)

    Audretsch, Christof; Lopez, Daniel; Srivastava, Mugdha; Wolz, Christiane; Dandekar, Thomas

    2013-11-01

    Staphylococcus aureus (SA) causes infections including severe sepsis by antibiotic-resistant strains. It forms biofilms to protect itself from the host and antibiotics. Biofilm and planktonic lifestyle are regulated by a complex quorum sensing system (QS) with the central regulator agr. To study biofilm formation and QS we set up a Boolean node interaction network (94 nodes, 184 edges) that included different two component systems such as agr, sae and arl. Proteins such as sar, rot and sigB were included. Each gene node represents the resulting activity of its gene products (mRNA and protein). Network consistency was tested according to previous knowledge and the literature. Regulator mutation combinations (agr-, sae-, sae-/agr-, sigB+, sigB+/sae-) were tested in silico in the model and compared regarding system changes and responses to experimental gene expression data. High connectivity served as a guide to identify master regulators, and their detailed behaviour was studied both in vitro and in the model. System analysis showed two stable states, biofilm forming versus planktonic, with clearly different sub-networks turned on. Predicted node activity changes from the in silico model were in line with microarray gene expression data of different knockout strains. Additional in silico predictions about node activity and biofilm formation were compared to new in vitro experiments (northern blots and biofilm adherence assays) which confirmed these. Further experiments in silico as well as in vitro showed the sae locus as the central modulator of biofilm production. Sae knockout strains showed stronger biofilms. Wild type phenotype was rescued by sae complementation. The in silico network provides a theoretical model that agrees well with the presented experimental data on how integration of different inputs is achieved in the QS of SA. It faithfully reproduces the behaviour of QS mutants and their biofilm forming ability and allows predictions about mutations and

  16. Quality control and conduct of genome-wide association meta-analyses

    DEFF Research Database (Denmark)

    Winkler, Thomas W; Day, Felix R; Croteau-Chonka, Damien C

    2014-01-01

    Rigorous organization and quality control (QC) are necessary to facilitate successful genome-wide association meta-analyses (GWAMAs) of statistics aggregated across multiple genome-wide association studies. This protocol provides guidelines for (i) organizational aspects of GWAMAs, and for (ii) QC...... at the study file level, the meta-level across studies and the meta-analysis output level. Real-world examples highlight issues experienced and solutions developed by the GIANT Consortium that has conducted meta-analyses including data from 125 studies comprising more than 330,000 individuals. We provide...

  17. 遗传关联研究Meta分析中文文献方法学质量评价%Methodological quality of Meta-analyses regarding studies related to genetic association on papers published in Chinese journals

    Institute of Scientific and Technical Information of China (English)

    李帅; 方凯; 孙傲伊; 孙可欣; 胡永华

    2013-01-01

    目的 评价遗传关联研究Meta分析中文文献的方法学质量.方法 检索中国生物医学数据库、中国期刊全文数据库(CNKI)、万方数据资源系统和维普中国科技期刊全文数据库2012年12月前的遗传关联研究Meta分析文章.2名研究者独立按纳入排除标准进行文献筛选,意见不一致时咨询第三位研究者.运用系统综述评价工具(AMSTAR)量表对入选文献的方法学质量进行评价.结果 共纳入440篇文献.方法学质量得分平均为5.77分(满分11分).没有文章符合AMSTAR量表全部11项条目的要求.人选文章中,89.5%有前期设计方案,38.6%在纳入文献和信息提取方面有可重复性,72.7%实施了广泛文献检索,14.8%考虑了文献发表状态,10.9%提供了纳入和排除文献清单,92.5%描述了纳入文献特征,32.0%评估了文献质量,50.0%将文献质量用于结论推导,93.2%合并文献结果方法恰当,82.3%评估了发表偏倚,0.5%声明利益冲突.结论 遗传关联研究Meta分析中文文章方法学质量中等,在文献的筛选和信息提取、考虑文献的发表情况、提供纳入和排除文献清单、对文献进行质量评估、声明利益冲突等方面需要提高.%Objective To assess the methodological quality of Meta-analyses on papers published in Chinese journals regarding studies on genetic association.Methods Meta-analyses of genetic association study published in Chinese journals up to December 2012 had been searched through on 4 Chinese electronic databases (China biomedicine database,CNKI,Wanfang database and VIP Information).Articles independently selected by both two researchers under definite inclusion and exclusion criteria were included in this study (with consultation on a third researcher if inconsistent opinions existed).A Measurement Tool for the Assessment of Multiple Systematic Reviews (AMSTAR) checklist was used to evaluate the methodological quality together with the

  18. A Systematic Review of Meta-Analyses on Gene Polymorphisms and Gastric Cancer Risk

    Science.gov (United States)

    Gianfagna, Francesco; De Feo, Emma; van Duijn, Cornelia M; Ricciardi, Gualtiero; Boccia, Stefania

    2008-01-01

    Background Individual variations in gastric cancer risk have been associated in the last decade with specific variant alleles of different genes that are present in a significant proportion of the population. Polymorphisms may modify the effects of environmental exposures, and these gene-environment interactions could partly explain the high variation of gastric cancer incidence around the world. The aim of this report is to carry out a systematic review of the published meta-analyses of studies investigating the association between gene polymorphisms and gastric cancer risk, and describe their impact at population level. Priorities on the design of further primary studies are then provided. Methods A structured bibliographic search on Medline and EMBASE databases has been performed to identify meta-analyses on genetic susceptibility to gastric cancer, without restriction criteria. We report the main results of the meta-analyses and we describe the subgroup analyses performed, focusing on the detection of statistical heterogeneity. We investigated publication bias by pooling the primary studies included in the meta-analyses, and we computed the population attributable risk (PAR) for each polymorphism. Results Twelve meta-analyses and one pooled-analysis of community based genetic association studies were included, focusing on nine genes involved in inflammation (IL-1β, IL-1RN, IL-8), detoxification of carcinogens (GSTs, CYP2E1), folate metabolism (MTHFR), intercellular adhesion (E-cadherin) and cell cycle regulation (p53). According to their random-Odds Ratios, individuals carrying one of the IL-1RN *2, IL-1β -511T variant alleles or homozygotes for MTHFR 677T are significantly at higher risk of gastric cancer than those with the wild type homozygote genotypes, showing high PARs. The main sources of heterogeneity in the meta-analyses were ethnicity, quality of the primary study, and selected environmental co-exposures. Effect modification by Helicobacter pylori

  19. [Meta-analyses of quarks, baryons and mesons--a "Cochrane Collaboration" in particle physics].

    Science.gov (United States)

    Sauerland, Stefan; Sauerland, Thankmar; Antes, Gerd; Barnett, R Michael

    2002-02-01

    Within the last 20 years meta-analysis has become an important research technique in medicine for integrating the results of independent studies. Meta-analytical techniques, however, are much older. In particle physics for 50 years now the properties of huge numbers of particles have been assessed in meta-analyses. The Cochrane Collaboration's counterpart in physics is the Particle Data Group. This article compares methodological and organisational aspects of meta-analyses in medicine and physics. Several interesting parallels exist, especially with regard to methodology.

  20. Strategies to improve the credibility of meta-analyses in spine surgery: a systematic survey.

    Science.gov (United States)

    Evaniew, Nathan; van der Watt, Leon; Bhandari, Mohit; Ghert, Michelle; Aleem, Ilyas; Drew, Brian; Guyatt, Gordon

    2015-09-01

    Meta-analyses are powerful tools that can synthesize existing research, inform clinical practice, and support evidence-based care. These studies have become increasingly popular in the spine surgery literature, but the rigor with which they are being conducted has not yet been evaluated. Our primary objectives were to evaluate the methodological quality (credibility) of spine surgery meta-analyses and to propose strategies to improve future research. Our secondary objectives were to evaluate completeness of reporting and identify factors associated with higher credibility and completeness of reporting. This study is based on a systematic survey of meta-analyses. We evaluated credibility according to the Users' Guide to the Medical Literature and completeness of reporting according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. We systematically searched MEDLINE, EMBASE, and The Cochrane Library, and two reviewers independently assessed eligibility, credibility, and completeness of reporting. We used multivariable linear regression to evaluate potential associations. Interrater agreement was quantified using kappa and intraclass correlation (ICC) coefficients. We identified 132 eligible meta-analyses of spine surgery interventions. The mean credibility score was 3 of 7 (standard deviation [SD], 1.4; ICC, 0.86), with agreement for each item ranging from 0.54 (moderate) to 0.83 (almost perfect). Clinical questions were judged as sensible in 125 (95%), searches were exhaustive in 102 (77%), and risk of bias assessments were undertaken in 91 (69%). Seven (5%) meta-analyses addressed possible explanations for heterogeneity using a priori subgroup hypotheses and 24 (18%) presented results that were immediately clinically applicable. Investigators undertook duplicate assessments of eligibility, risk of bias, and data extraction in 46 (35%) and rated overall confidence in the evidence in 24 (18%). Later publication year, increasing

  1. Comparison of statistical inferences from the DerSimonian-Laird and alternative random-effects model meta-analyses - an empirical assessment of 920 Cochrane primary outcome meta-analyses

    DEFF Research Database (Denmark)

    Thorlund, Kristian; Wetterslev, Jørn; Awad, Tahany;

    2011-01-01

    In random-effects model meta-analysis, the conventional DerSimonian-Laird (DL) estimator typically underestimates the between-trial variance. Alternative variance estimators have been proposed to address this bias. This study aims to empirically compare statistical inferences from random......-effects model meta-analyses on the basis of the DL estimator and four alternative estimators, as well as distributional assumptions (normal distribution and t-distribution) about the pooled intervention effect. We evaluated the discrepancies of p-values, 95% confidence intervals (CIs) in statistically...... significant meta-analyses, and the degree (percentage) of statistical heterogeneity (e.g. I(2)) across 920 Cochrane primary outcome meta-analyses. In total, 414 of the 920 meta-analyses were statistically significant with the DL meta-analysis, and 506 were not. Compared with the DL estimator, the four...

  2. Biomarkers and Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-Analyses

    Science.gov (United States)

    Scassellati, Catia; Bonvicini, Cristian; Faraone, Stephen V.; Gennarelli, Massimo

    2012-01-01

    Objective: To determine whether peripheral biochemical markers (biomarkers) might differentiate patients with attention-deficit/hyperactivity disorder (ADHD) from non-ADHD individuals. Method: We conducted a systematic search and a series of meta-analyses of case-control studies comprising studies from 1969 to 2011. Results: We identified 210…

  3. Biomarkers and Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-Analyses

    Science.gov (United States)

    Scassellati, Catia; Bonvicini, Cristian; Faraone, Stephen V.; Gennarelli, Massimo

    2012-01-01

    Objective: To determine whether peripheral biochemical markers (biomarkers) might differentiate patients with attention-deficit/hyperactivity disorder (ADHD) from non-ADHD individuals. Method: We conducted a systematic search and a series of meta-analyses of case-control studies comprising studies from 1969 to 2011. Results: We identified 210…

  4. The top-cited systematic reviews/meta-analyses in tuberculosis research

    Science.gov (United States)

    Zhang, Yonggang; Huang, Jin; Du, Liang

    2017-01-01

    Abstract Background: The top-cited systematic reviews/meta-analyses in tuberculosis research have not been identified. The objective of this study was to identify the 100 top-cited systematic reviews/meta-analyses in tuberculosis research, and to understand factors resulting in highly cited works, and establish trends in systematic reviews/meta-analyses in tuberculosis research. Methods: The Web of Science Core Collection was searched for systematic reviews/meta-analyses on tuberculosis up to January 31, 2016. Articles were ranked by citation count and screened by 2 authors. The following information was collected and analyzed from each included study: citation of Web of Science Core Collection, author, country, year, journal, institution, page number, and reference number. Results: The 100 top-cited studies were cited from 54 to 662 times and were published between 1997 and 2014. Ten authors have more than 1 study as the first author and 10 authors have more than 1 study as corresponding author. The country with the most top-cited studies was USA (n = 26). The institutions with the largest number of the studies were McGill University in Canada (n = 18). The studies were published in 32 journals, whereas 12 were published in PloS Medicine, followed by Lancet Infectious Diseases (n = 11). Conclusions: Developed countries and high-impact journals may publish more top-cited systematic review/meta-analysis in tuberculosis research. PMID:28178120

  5. Sex based subgroup differences in randomized controlled trials: Empirical evidence from Cochrane meta-analyses

    NARCIS (Netherlands)

    Wallach, J.D. (Joshua D.); Sullivan, P.G. (Patrick G.); Trepanowski, J.F. (John F.); E.W. Steyerberg (Ewout); J.P.A. Ioannidis (John)

    2016-01-01

    textabstractObjective To evaluate the frequency, validity, and relevance of statistically significant (P<0.05) sex-treatment interactions in randomized controlled trials in Cochrane meta-analyses. Design Meta-epidemiological study. Data sources Cochrane Database of Systematic Reviews (CDSR) and PubM

  6. Reporting of conflicts of interests in meta-analyses of trials of pharmacological treatments

    NARCIS (Netherlands)

    Roseman, M.; Milette, K.; Bero, A.B.; Coyne, J.C.; Lexchin, J.; Turner, E.H.; Thombs, B.D.

    2011-01-01

    Abstract CONTEXT: Disclosure of conflicts of interest (COIs) from pharmaceutical industry study funding and author-industry financial relationships is sometimes recommended for randomized controlled trials (RCTs) published in biomedical journals. Authors of meta-analyses, however, are not required t

  7. Reporting of Conflicts of Interest in Meta-analyses of Trials of Pharmacological Treatments

    NARCIS (Netherlands)

    Roseman, Michelle; Milette, Katherine; Bero, Lisa A.; Coyne, James C.; Lexchin, Joel; Turner, Erick H.; Thombs, Brett D.

    2011-01-01

    Context Disclosure of conflicts of interest (COIs) from pharmaceutical industry study funding and author-industry financial relationships is sometimes recommended for randomized controlled trials (RCTs) published in biomedical journals. Authors of meta-analyses, however, are not required to report C

  8. Sex based subgroup differences in randomized controlled trials: Empirical evidence from Cochrane meta-analyses

    NARCIS (Netherlands)

    Wallach, J.D. (Joshua D.); Sullivan, P.G. (Patrick G.); Trepanowski, J.F. (John F.); E.W. Steyerberg (Ewout); J.P.A. Ioannidis (John)

    2016-01-01

    textabstractObjective To evaluate the frequency, validity, and relevance of statistically significant (P<0.05) sex-treatment interactions in randomized controlled trials in Cochrane meta-analyses. Design Meta-epidemiological study. Data sources Cochrane Database of Systematic Reviews (CDSR) and

  9. Statistics for quantifying heterogeneity in univariate and bivariate meta-analyses of binary data: the case of meta-analyses of diagnostic accuracy.

    Science.gov (United States)

    Zhou, Yan; Dendukuri, Nandini

    2014-07-20

    Heterogeneity in diagnostic meta-analyses is common because of the observational nature of diagnostic studies and the lack of standardization in the positivity criterion (cut-off value) for some tests. So far the unexplained heterogeneity across studies has been quantified by either using the I(2) statistic for a single parameter (i.e. either the sensitivity or the specificity) or visually examining the data in a receiver-operating characteristic space. In this paper, we derive improved I(2) statistics measuring heterogeneity for dichotomous outcomes, with a focus on diagnostic tests. We show that the currently used estimate of the 'typical' within-study variance proposed by Higgins and Thompson is not able to properly account for the variability of the within-study variance across studies for dichotomous variables. Therefore, when the between-study variance is large, the 'typical' within-study variance underestimates the expected within-study variance, and the corresponding I(2) is overestimated. We propose to use the expected value of the within-study variation in the construction of I(2) in cases of univariate and bivariate diagnostic meta-analyses. For bivariate diagnostic meta-analyses, we derive a bivariate version of I(2) that is able to account for the correlation between sensitivity and specificity. We illustrate the performance of these new estimators using simulated data as well as two real data sets.

  10. Identifying Useful Terms to Retrieve Survival Data Meta-Analyses Publications for Bibliographic Databases Search Strategies

    Directory of Open Access Journals (Sweden)

    Daniel Corneliu LEUCUŢA

    2009-12-01

    Full Text Available Introduction: Quality research and quality evidence based medicine practice has an important pillar in a solid bibliographic documentation. Quality bibliographic documentation makes use of search strategies to retrieve articles from search engines of bibliographic databases. The AIM of this study was the identification of useful search terms to be used in search strategies that try to find meta-analyses of survival data. Materials and methods: A qualitative study based on text analysis was undertaken to identify useful terms for search strategies in abstracts of scientific papers. Survival analysis meta-analyses publication type studies, published between 1996 and 2005, were searched in Medline bibliographic database through Pubmed web interface. Each abstract was analysed and each important terms were noted down if they were considered to be useful in the creation of search strategies for analysis of survival data, or meta-analyses. Results: Pubmed search yielded 773 results. From these search results 401 (52% fulfilled inclusion criteria. The terms that were identified as useful in search strategies for meta-analyses of survival data are presented in the paper.

  11. Handedness prevalence in the deaf: Meta-analyses.

    Science.gov (United States)

    Papadatou-Pastou, Marietta; Sáfár, Anna

    2016-01-01

    An under-investigated aspect of handedness, a biological proxy for cerebral laterality for language, is its prevalence amongst deaf individuals. We present four sets of meta-analyses on studies measuring handedness prevalence in deaf individuals, comprising 31 data sets and totaling 5,392 participants (4,606 deaf, 786 hearing). Deaf individuals were found to be 2.61 times more likely to be non-right-handed and 2.25 times more likely to be left-handed compared to their hearing counterparts. When handedness was measured by means of manipulative actions, the weighted estimates of handedness prevalence for deaf populations were 17.70% and 14.70% for non-right- and left-handedness respectively; when handedness was measured by means of sign actions, the prevalence was 10.60% and 9.70%, respectively. Yet, when comparing studies that measured handedness in the same deaf individuals using both manipulative and sign actions, no difference was found in their handedness prevalence. This pattern is taken to suggest that the higher prevalence of atypical handedness in the deaf population may be linked to delayed language acquisition.

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

    Science.gov (United States)

    Valkenburg, Patti M

    2015-09-01

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

  13. Weighing Evidence "Steampunk" Style via the Meta-Analyser.

    Science.gov (United States)

    Bowden, Jack; Jackson, Chris

    2016-10-01

    The funnel plot is a graphical visualization of summary data estimates from a meta-analysis, and is a useful tool for detecting departures from the standard modeling assumptions. Although perhaps not widely appreciated, a simple extension of the funnel plot can help to facilitate an intuitive interpretation of the mathematics underlying a meta-analysis at a more fundamental level, by equating it to determining the center of mass of a physical system. We used this analogy to explain the concepts of weighing evidence and of biased evidence to a young audience at the Cambridge Science Festival, without recourse to precise definitions or statistical formulas and with a little help from Sherlock Holmes! Following on from the science fair, we have developed an interactive web-application (named the Meta-Analyser) to bring these ideas to a wider audience. We envisage that our application will be a useful tool for researchers when interpreting their data. First, to facilitate a simple understanding of fixed and random effects modeling approaches; second, to assess the importance of outliers; and third, to show the impact of adjusting for small study bias. This final aim is realized by introducing a novel graphical interpretation of the well-known method of Egger regression.

  14. Guidelines for Meta-Analyses of Counseling Psychology Research

    Science.gov (United States)

    Quintana, Stephen M.; Minami, Takuya

    2006-01-01

    This article conceptually describes the steps in conducting quantitative meta-analyses of counseling psychology research with minimal reliance on statistical formulas. The authors identify sources that describe necessary statistical formula for various meta-analytic calculations and describe recent developments in meta-analytic techniques. The…

  15. Minimally invasive versus open surgery for acute Achilles tendon rupture: a systematic review of overlapping meta-analyses.

    Science.gov (United States)

    Li, Qingbo; Wang, Chuanying; Huo, Yanqing; Jia, Zhiwei; Wang, Xiqian

    2016-06-06

    A number of meta-analyses have been carried out to evaluate the effects of minimally invasive surgery (MIS) versus open surgery (OS) for acute Achilles tendon rupture. However, discordant findings were seen in these meta-analyses. The present study, performing a systematic review of overlapping meta-analyses regarding MIS versus OS of acute Achilles tendon rupture, aimed to assist decision-makers interpret and choose among conflicting meta-analyses, as well as to offer treatment recommendations based on current best evidence. The literature search was performed to identify systematic reviews comparing MIS with OS for Achilles tendon rupture. Meta-analyses only comprising randomized controlled trials (RCTs) were included. Two authors individually evaluated the quality of meta-analysis and extracted data. The Jadad decision algorithm was conducted to ascertain which meta-analysis offered the best evidence. A total of four meta-analyses was included. All these meta-analyses comprised RCTs or quasi-RCTs and were determined as Level-II evidence. The scores of the Assessment of Multiple Systematic Reviews (AMSTAR) ranged from 7 to 10 (median 9.5). The Jadad algorithm indicated that the best meta-analysis should be chosen according to the search strategies and application of selection. A high-quality meta-analysis with more RCTs was chosen, which suggested that there was no statistically significant difference between MIS and OS regarding rerupture rate, tissue adhesion, sural nerve injury, deep infection, and deep vein thrombosis. However, MIS could decrease superficial infection rate, and had a better patient satisfaction for good to excellent outcomes in comparison to OS. Based on the best available evidence, MIS may be superior to OS for treating acute Achilles tendon rupture. However, due to some limitations, this should be cautiously interpreted, and further high-quality studies are needed.

  16. Systematic review and meta-analyses

    DEFF Research Database (Denmark)

    Dreier, Julie Werenberg; Andersen, Anne-Marie Nybo; Berg-Beckhoff, Gabriele

    2014-01-01

    was to systematically review evidence from epidemiologic studies on adverse health outcomes of the offspring in relation to exposure to maternal fever during pregnancy. METHODS: Systematic searches in PubMed, Web of Science, and the Cochrane Library were performed by using Medical Subject Headings, Boolean operators......, and truncation, and references of references were reviewed. Cohort and case-control studies addressing health outcomes of prenatal fever exposure in humans were eligible for inclusion. Studies with no direct reference to fever, studies in selected populations (eg, preterm births), and studies published before.......5- and nearly 3-fold increased risk with fever exposure in the first trimester. We did not find strong evidence of a dose-response relationship, but there was some evidence that antipyretic medications may have a protective effect when used in relation to febrile episodes. CONCLUSIONS: We found substantial...

  17. Reporting quality of systematic reviews/meta-analyses of acupuncture.

    Directory of Open Access Journals (Sweden)

    Yali Liu

    Full Text Available The QUOROM and PRISMA statements were published in 1999 and 2009, respectively, to improve the consistency of reporting systematic reviews (SRs/meta-analyses (MAs of clinical trials. However, not all SRs/MAs adhere completely to these important standards. In particular, it is not clear how well SRs/MAs of acupuncture studies adhere to reporting standards and which reporting criteria are generally ignored in these analyses.To evaluate reporting quality in SRs/MAs of acupuncture studies.We performed a literature search for studies published prior to 2014 using the following public archives: PubMed, EMBASE, Web of Science, the Cochrane Database of Systematic Reviews (CDSR, the Chinese Biomedical Literature Database (CBM, the Traditional Chinese Medicine (TCM database, the Chinese Journal Full-text Database (CJFD, the Chinese Scientific Journal Full-text Database (CSJD, and the Wanfang database. Data were extracted into pre-prepared Excel data-extraction forms. Reporting quality was assessed based on the PRISMA checklist (27 items.Of 476 appropriate SRs/MAs identified in our search, 203, 227, and 46 were published in Chinese journals, international journals, and the Cochrane Database, respectively. In 476 SRs/MAs, only 3 reported the information completely. By contrast, approximately 4.93% (1/203, 8.81% (2/227 and 0.00% (0/46 SRs/Mas reported less than 10 items in Chinese journals, international journals and CDSR, respectively. In general, the least frequently reported items (reported≤50% in SRs/MAs were "protocol and registration", "risk of bias across studies", and "additional analyses" in both methods and results sections.SRs/MAs of acupuncture studies have not comprehensively reported information recommended in the PRISMA statement. Our study underscores that, in addition to focusing on careful study design and performance, attention should be paid to comprehensive reporting standards in SRs/MAs on acupuncture studies.

  18. Reporting Quality of Systematic Reviews/Meta-Analyses of Acupuncture

    Science.gov (United States)

    Liu, Yali; Zhang, Rui; Huang, Jiao; Zhao, Xu; Liu, Danlu; Sun, Wanting; Mai, Yuefen; Zhang, Peng; Wang, Yajun; Cao, Hua; Yang, Ke hu

    2014-01-01

    Background The QUOROM and PRISMA statements were published in 1999 and 2009, respectively, to improve the consistency of reporting systematic reviews (SRs)/meta-analyses (MAs) of clinical trials. However, not all SRs/MAs adhere completely to these important standards. In particular, it is not clear how well SRs/MAs of acupuncture studies adhere to reporting standards and which reporting criteria are generally ignored in these analyses. Objectives To evaluate reporting quality in SRs/MAs of acupuncture studies. Methods We performed a literature search for studies published prior to 2014 using the following public archives: PubMed, EMBASE, Web of Science, the Cochrane Database of Systematic Reviews (CDSR), the Chinese Biomedical Literature Database (CBM), the Traditional Chinese Medicine (TCM) database, the Chinese Journal Full-text Database (CJFD), the Chinese Scientific Journal Full-text Database (CSJD), and the Wanfang database. Data were extracted into pre-prepared Excel data-extraction forms. Reporting quality was assessed based on the PRISMA checklist (27 items). Results Of 476 appropriate SRs/MAs identified in our search, 203, 227, and 46 were published in Chinese journals, international journals, and the Cochrane Database, respectively. In 476 SRs/MAs, only 3 reported the information completely. By contrast, approximately 4.93% (1/203), 8.81% (2/227) and 0.00% (0/46) SRs/Mas reported less than 10 items in Chinese journals, international journals and CDSR, respectively. In general, the least frequently reported items (reported≤50%) in SRs/MAs were “protocol and registration”, “risk of bias across studies”, and “additional analyses” in both methods and results sections. Conclusions SRs/MAs of acupuncture studies have not comprehensively reported information recommended in the PRISMA statement. Our study underscores that, in addition to focusing on careful study design and performance, attention should be paid to comprehensive reporting standards

  19. 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…

  20. Systematic reviews and meta-analyses of diagnostic test accuracy.

    Science.gov (United States)

    Leeflang, M M G

    2014-02-01

    Systematic reviews of diagnostic test accuracy summarize the accuracy, e.g. the sensitivity and specificity, of diagnostic tests in a systematic and transparent way. The aim of such a review is to investigate whether a test is sufficiently specific or sensitive to fit its role in practice, to compare the accuracy of two or more diagnostic tests, or to investigate where existing variation in results comes from. The search strategy should be broad and preferably fully reported, to enable readers to assess the completeness of it. Included studies usually have a cross-sectional design in which the tests of interest, ideally both the index test and its comparator, are evaluated against the reference standard. They should be a reflection of the situation that the review question refers to. The quality of included studies is assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 checklist, containing items such as a consecutive and all-inclusive patient selection process, blinding of index test and reference standard assessment, a valid reference standard, and complete verification of all included participants. Studies recruiting cases separately from (healthy) controls are regarded as bearing a high risk of bias. For meta-analysis, the bivariate model or the hierarchical summary receiver operating characteristic model is used. These models take into account potential threshold effects and the correlation between sensitivity and specificity. They also allow addition of covariates for investigatation of potential sources of heterogeneity. Finally, the results from the meta-analyses should be explained and interpreted for the reader, to be well understood.

  1. Meta-Analyses and Orthodontic Evidence-Based Clinical Practice in the 21st Century

    Science.gov (United States)

    Papadopoulos, Moschos A.

    2010-01-01

    Introduction: Aim of this systematic review was to assess the orthodontic related issues which currently provide the best evidence as documented by meta-analyses, by critically evaluating and discussing the methodology used in these studies. Material and Methods: Several electronic databases were searched and handsearching was also performed in order to identify the corresponding meta-analyses investigating orthodontic related subjects. In total, 197 studies were retrieved initially. After applying specific inclusion and exclusion criteria, 27 articles were identified as meta-analyses treating orthodontic-related subjects. Results: Many of these 27 papers presented sufficient quality and followed appropriate meta-analytic approaches to quantitatively synthesize data and presented adequately supported evidence. However, the methodology used in some of them presented weaknesses, limitations or deficiencies. Consequently, the topics in orthodontics which currently provide the best evidence, include some issues related to Class II or Class III treatment, treatment of transverse problems, external apical root resorption, dental anomalies, such as congenital missing teeth and tooth transposition, frequency of severe occlusal problems, nickel hypersensitivity, obstructive sleep apnea syndrome, and computer-assisted learning in orthodontic education. Conclusions: Only a few orthodontic related issues have been so far investigated by means of MAs. In addition, for some of these issues investigated in the corresponding MAs no definite conclusions could be drawn, due to significant methodological deficiencies of these studies. According to this investigation, it can be concluded that at the begin of the 21st century there is evidence for only a few orthodontic related issues as documented by meta-analyses, and more well-conducted high quality research studies are needed to produce strong evidence in order to support evidence-based clinical practice in orthodontics. PMID

  2. Adaptive and repeated cumulative meta-analyses of safety data during a new drug development process.

    Science.gov (United States)

    Quan, Hui; Ma, Yingqiu; Zheng, Yan; Cho, Meehyung; Lorenzato, Christelle; Hecquet, Carole

    2015-01-01

    During a new drug development process, it is desirable to timely detect potential safety signals. For this purpose, repeated meta-analyses may be performed sequentially on accumulating safety data. Moreover, if the amount of safety data from the originally planned program is not enough to ensure adequate power to test a specific hypothesis (e.g., the noninferiority hypothesis of an event of interest), the total sample size may be increased by adding new studies to the program. Without appropriate adjustment, it is well known that the type I error rate will be inflated because of repeated analyses and sample size adjustment. In this paper, we discuss potential issues associated with adaptive and repeated cumulative meta-analyses of safety data conducted during a drug development process. We consider both frequentist and Bayesian approaches. A new drug development example is used to demonstrate the application of the methods.

  3. Effectiveness of Chinese herbal medicine for cancer palliative care: overview of systematic reviews with meta-analyses.

    Science.gov (United States)

    Chung, Vincent C H; Wu, Xinyin; Hui, Edwin P; Ziea, Eric T C; Ng, Bacon F L; Ho, Robin S T; Tsoi, Kelvin K F; Wong, Samuel Y S; Wu, Justin C Y

    2015-01-01

    Chinese herbal medicines (CHM) are often used in managing cancer related symptoms but their effectiveness and safety is controversial. We conducted this overview of meta-analyses to summarize evidence on CHM for cancer palliative care. We included systematic reviews (SRs) with meta-analyses of CHM clinical trials on patients diagnosed with any type of cancer. Methodological quality of included meta-analyses was assessed with the Methodological Quality of Systematic Reviews (AMSTAR) Instrument. Fifty-one SRs with meta-analyses were included. They covered patients with lung (20 SRs), gastric (8 SRs), colorectal (6 SRs), liver (6 SRs), breast (2 SRs), cervical (1 SR), esophageal (1 SR), and nasopharyngeal (1 SR) cancers. Six SRs summarized evidence on various types of cancer. Methodological quality of included meta-analyses was not satisfactory. Overall, favorable therapeutic effects in improving quality of life among cancer patients have been reported. Conflicting evidence exists for the effectiveness of CHM in prolonging survival and in reducing chemotherapy and/or radiotherapy related toxicities. No serious adverse effects were reported in all included studies. Evidence indicated that CHM could be considered as an option for improving quality of life among patients receiving palliative care. It is unclear if CHM may increase survival, or reduce therapy related toxicities.

  4. Identifying neural correlates of visual consciousness with ALE meta-analyses.

    Science.gov (United States)

    Bisenius, Sandrine; Trapp, Sabrina; Neumann, Jane; Schroeter, Matthias L

    2015-11-15

    Neural correlates of consciousness (NCC) have been a topic of study for nearly two decades. In functional imaging studies, several regions have been proposed to constitute possible candidates for NCC, but as of yet, no quantitative summary of the literature on NCC has been done. The question whether single (striate or extrastriate) regions or a network consisting of extrastriate areas that project directly to fronto-parietal regions are necessary and sufficient neural correlates for visual consciousness is still highly debated [e.g., Rees et al., 2002, Nat Rev. Neurosci 3, 261-270; Tong, 2003, Nat Rev. Neurosci 4, 219-229]. The aim of this work was to elucidate this issue and give a synopsis of the present state of the art by conducting systematic and quantitative meta-analyses across functional magnetic resonance imaging (fMRI) studies using several standard paradigms for conscious visual perception. In these paradigms, consciousness is operationalized via perceptual changes, while the visual stimulus remains invariant. An activation likelihood estimation (ALE) meta-analysis was performed, representing the best approach for voxel-wise meta-analyses to date. In addition to computing a meta-analysis across all paradigms, separate meta-analyses on bistable perception and masking paradigms were conducted to assess whether these paradigms show common or different NCC. For the overall meta-analysis, we found significant clusters of activation in inferior and middle occipital gyrus; fusiform gyrus; inferior temporal gyrus; caudate nucleus; insula; inferior, middle, and superior frontal gyri; precuneus; as well as in inferior and superior parietal lobules. These results suggest a subcortical-extrastriate-fronto-parietal network rather than a single region that constitutes the necessary NCC. The results of our exploratory paradigm-specific meta-analyses suggest that this subcortical-extrastriate-fronto-parietal network might be differentially activated as a function of the

  5. Editorial Commentary: Meta-analyses Are on the Rise, but Are We Learning More?

    Science.gov (United States)

    D'Agostino, Ralph B

    2016-03-01

    The number of published meta-analyses in the arthroscopy literature is clearly on the rise. As this increase occurs, it is important to step back and refresh ourselves on the key features of meta-analyses.

  6. Circulating biomarkers for predicting cardiovascular disease risk; a systematic review and comprehensive overview of meta-analyses.

    Directory of Open Access Journals (Sweden)

    Thijs C van Holten

    Full Text Available BACKGROUND: Cardiovascular disease is one of the major causes of death worldwide. Assessing the risk for cardiovascular disease is an important aspect in clinical decision making and setting a therapeutic strategy, and the use of serological biomarkers may improve this. Despite an overwhelming number of studies and meta-analyses on biomarkers and cardiovascular disease, there are no comprehensive studies comparing the relevance of each biomarker. We performed a systematic review of meta-analyses on levels of serological biomarkers for atherothrombosis to compare the relevance of the most commonly studied biomarkers. METHODS AND FINDINGS: Medline and Embase were screened on search terms that were related to "arterial ischemic events" and "meta-analyses". The meta-analyses were sorted by patient groups without pre-existing cardiovascular disease, with cardiovascular disease and heterogeneous groups concerning general populations, groups with and without cardiovascular disease, or miscellaneous. These were subsequently sorted by end-point for cardiovascular disease or stroke and summarized in tables. We have identified 85 relevant full text articles, with 214 meta-analyses. Markers for primary cardiovascular events include, from high to low result: C-reactive protein, fibrinogen, cholesterol, apolipoprotein B, the apolipoprotein A/apolipoprotein B ratio, high density lipoprotein, and vitamin D. Markers for secondary cardiovascular events include, from high to low result: cardiac troponins I and T, C-reactive protein, serum creatinine, and cystatin C. For primary stroke, fibrinogen and serum uric acid are strong risk markers. Limitations reside in that there is no acknowledged search strategy for prognostic studies or meta-analyses. CONCLUSIONS: For primary cardiovascular events, markers with strong predictive potential are mainly associated with lipids. For secondary cardiovascular events, markers are more associated with ischemia. Fibrinogen is a

  7. Surgical Versus Conservative Intervention for Acute Achilles Tendon Rupture: A PRISMA-Compliant Systematic Review of Overlapping Meta-Analyses.

    Science.gov (United States)

    Zhang, Hao; Tang, Hao; He, Qianyun; Wei, Qiang; Tong, Dake; Wang, Chuangfeng; Wu, Dajiang; Wang, Guangchao; Zhang, Xin; Ding, Wenbin; Li, Di; Ding, Chen; Liu, Kang; Ji, Fang

    2015-11-01

    Although many meta-analyses comparing surgical intervention with conservative treatment have been conducted for acute Achilles tendon rupture, discordant conclusions are shown. This study systematically reviewed the overlapping meta-analyses relating to surgical versus conservative intervention of acute Achilles tendon rupture to assist decision makers select among conflicting meta-analyses, and to offer intervention recommendations based on the currently best evidence.Multiple databases were comprehensively searched for meta-analyses comparing surgical with conservative treatment of acute Achilles tendon rupture. Meta-analyses only comprising randomized controlled trials (RCTs) were included. Two authors independently evaluated the meta-analysis quality and extracted data. The Jadad decision algorithm was applied to ascertain which meta-analysis offered the best evidence.A total of 9 meta-analyses were included. Only RCTs were determined as Level-II evidence. The scores of Assessment of Multiple Systematic Reviews (AMSTAR) ranged from 5 to 10 (median 7). A high-quality meta-analysis with more RCTs was selected according to the Jadad decision algorithm. This study found that when functional rehabilitation was used, conservative intervention was equal to surgical treatment regarding the incidence of rerupture, range of motion, calf circumference, and functional outcomes, while reducing the incidence of other complications. Where functional rehabilitation was not performed, conservative intervention could significantly increase rerupture rate.Conservative intervention may be preferred for acute Achilles tendon rupture at centers offering functional rehabilitation, because it shows a similar rerupture rate with a lower risk of other complications when compared with surgical treatment. However, surgical treatment should be considered at centers without functional rehabilitation as this can reduce the incidence of rerupture.

  8. Lack of consensus on the role of endoscopic retrograde cholangiography in acute biliary pancreatitis in published meta-analyses and guidelines: a systematic review

    NARCIS (Netherlands)

    Geenen, E.J.M. van; Santvoort, H.C. van; Besselink, M.G.; Peet, D.L. van der; Erpecum, K.J. van; Fockens, P.; Mulder, C.J.; Bruno, M.J.

    2013-01-01

    OBJECTIVES: Several randomized controlled trials studied the role of endoscopic retrograde cholangiopancreaticography (ERCP) and endoscopic sphincterotomy (ES) in acute biliary pancreatitis (ABP). No study assessed whether these trials resulted in international consensus in published meta-analyses a

  9. Systematic Comparison of Brain Imaging Meta-Analyses of ToM with vPT

    OpenAIRE

    Aditi Arora; Matthias Schurz; Josef Perner

    2017-01-01

    In visual perspective taking (vPT) one has to concern oneself with what other people see and how they see it. Since seeing is a mental state, developmental studies have discussed vPT within the domain of “theory of mind (ToM)” but imaging studies have not treated it as such. Based on earlier results from several meta-analyses, we tested for the overlap of visual perspective taking studies with 6 different kinds of ToM studies: false belief, trait judgments, strategic games, social animations,...

  10. How effective are active videogames among the young and the old? Adding meta-analyses to two recent systematic reviews

    NARCIS (Netherlands)

    Riet, J.P. van 't; Crutzen, R.; Shirong, L.A.

    2014-01-01

    Objective: Two recent systematic reviews have surveyed the existing evidence for the effectiveness of active videogames in children/adolescents and in elderly people. In the present study, effect sizes were added to these systematic reviews, and meta-analyses were performed. Materials and Methods: A

  11. Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data: the PRISMA-IPD Statement

    NARCIS (Netherlands)

    Stewart, L.A.; Clarke, M.; Rovers, M.M.; Riley, R.D.; Simmonds, M.; Stewart, G.; Tierney, J.F.

    2015-01-01

    IMPORTANCE: Systematic reviews and meta-analyses of individual participant data (IPD) aim to collect, check, and reanalyze individual-level data from all studies addressing a particular research question and are therefore considered a gold standard approach to evidence synthesis. They are likely to

  12. Genome-wide meta-analyses of multiancestry cohorts identify multiple new susceptibility loci for refractive error and myopia

    NARCIS (Netherlands)

    V.J.M. Verhoeven (Virginie); P.G. Hysi (Pirro); R. Wojciechowski (Robert); Q. Fan (Qiao); J. Guggenheim (Jean); R. Höhn (René); S. MacGregor (Stuart); A.W. Hewit (Alex); A. Nag (Abhishek); C-Y. Cheng (Ching-Yu); E. Yonova-Doing (Ekaterina); X. Zhou (Xin); M.K. Ikram (Kamran); G.H.S. Buitendijk (Gabrielle); G. Mcmahon (George); J.P. Kemp (John); B.S. Pourcain (Beate); C.L. Simpson (Claire); M.J. Mäkelä; T. Lehtimäki (Terho); M. Kähönen (Mika); A.D. Paterson (Andrew); M. Hosseini (Mehran); H.S. Wong (Hoi Suen); L. Xu (Liang); J.B. Jonas; O. Pärssinen (Olavi); J. Wedenoja (Juho); S.P. Yip (Shea Ping); D.W.H. Ho (Daniel); C.P. Pang (Chi); L.J. Chen (Li); K.P. Burdon (Kathryn); J.E. Craig (Jamie); B.E.K. Klein (Barbara); B.E.K. Klein (Barbara); T. Haller (Toomas); A. Metspalu (Andres); C.C. Khor; E.S. Tai (Shyong); T. Aung (Tin); E.N. Vithana (Eranga); W.-T. Tay (Wan-Ting); V.A. Barathi (Veluchamy); P. Chen (Ping); R. Li (Rui); J. Liao (Jie); Y. Zheng (Yuhui); R.T.H. Ong (Rick Twee-Hee); A. Döring (Angela); D.M. Evans (David); N. Timpson (Nicholas); A. Verkerk; T. Meitinger (Thomas); O. Raitakari (Olli); F. Hawthorne (Felicia); T.D. Spector (Timothy); L.C. Karssen (Lennart); M. Pirastu (Mario); D. Murgia (Daniela); W.Q. Ang (Wei); A. Mishra (Aniket); G.W. Montgomery (Grant); C.E. Pennell (Craig); P. Cumberland (Phillippa); I. Cotlarciuc (Ioana); P. Mitchell (Paul); J.J. Wang (Jie Jin); M. Schache (Maria); S. Janmahasathian (Sarayut); R.P. Igo Jr. (Robert); J.H. Lass Jr. (Jonathan); E.Y. Chew (Emily); S.K. Iyengar (Sudha); T.G.M.F. Gorgels (Theo); I. Rudan (Igor); C. Hayward (Caroline); A.F. Wright (Alan); O. Polasek (Ozren); Z. Vatavuk (Zoran); J.F. Wilson (James); B. Fleck (Brian); T. Zeller (Tanja); A. Mirshahi (Alireza); C. Müller (Christian); A.G. Uitterlinden (André); F. Rivadeneira Ramirez (Fernando); J.R. Vingerling (Hans); A. Hofman (Albert); B.A. Oostra (Ben); N. Amin (Najaf); A.A.B. Bergen (Arthur); Y.Y. Teo (Yik Ying); J.S. Rahi (Jugnoo); V. Vitart (Veronique); C. Williams (Cathy); P.N. Baird (Paul); T.Y. Wong (Tien); K. Oexle (Konrad); A.F.H. Pfeiffer (Andreas); D.A. Mackey (David); T.L. Young (Terri); C.M. van Duijn (Cock); S-M. Saw (Seang-Mei); J.E. Bailey-Wilson (Joan); D.E. Stambolian (Dwight); C.C.W. Klaver (Caroline); C.J. Hammond (Christopher)

    2013-01-01

    textabstractRefractive error is the most common eye disorder worldwide and is a prominent cause of blindness. Myopia affects over 30% of Western populations and up to 80% of Asians. The CREAM consortium conducted genome-wide meta-analyses, including 37,382 individuals from 27 studies of European anc

  13. Genome-wide meta-analyses of multiancestry cohorts identify multiple new susceptibility loci for refractive error and myopia

    NARCIS (Netherlands)

    V.J.M. Verhoeven (Virginie); P.G. Hysi (Pirro); R. Wojciechowski (Robert); Q. Fan (Qiao); J. Guggenheim (Jean); R. Höhn (René); S. MacGregor (Stuart); A.W. Hewit (Alex); A. Nag (Abhishek); C-Y. Cheng (Ching-Yu); E. Yonova-Doing (Ekaterina); X. Zhou (Xin); M.K. Ikram (Kamran); G.H.S. Buitendijk (Gabrielle); G. Mcmahon (George); J.P. Kemp (John); B.S. Pourcain (Beate); C.L. Simpson (Claire); M.J. Mäkelä; T. Lehtimäki (Terho); M. Kähönen (Mika); A.D. Paterson (Andrew); M. Hosseini (Mehran); H.S. Wong (Hoi Suen); L. Xu (Liang); J.B. Jonas; O. Pärssinen (Olavi); J. Wedenoja (Juho); S.P. Yip (Shea Ping); D.W.H. Ho (Daniel); C.P. Pang (Chi); L.J. Chen (Li); K.P. Burdon (Kathryn); J.E. Craig (Jamie); B.E.K. Klein (Barbara); B.E.K. Klein (Barbara); T. Haller (Toomas); A. Metspalu (Andres); C.C. Khor; E.S. Tai (Shyong); T. Aung (Tin); E.N. Vithana (Eranga); W.-T. Tay (Wan-Ting); V.A. Barathi (Veluchamy); P. Chen (Ping); R. Li (Rui); J. Liao (Jie); Y. Zheng (Yuhui); R.T.H. Ong (Rick Twee-Hee); A. Döring (Angela); D.M. Evans (David); N.J. Timpson (Nicholas); A. Verkerk; T. Meitinger (Thomas); O. Raitakari (Olli); F. Hawthorne (Felicia); T.D. Spector (Timothy); L.C. Karssen (Lennart); M. Pirastu (Mario); D. Murgia (Daniela); W.Q. Ang (Wei); A. Mishra (Aniket); G.W. Montgomery (Grant); C.E. Pennell (Craig); P. Cumberland (Phillippa); I. Cotlarciuc (Ioana); P. Mitchell (Paul); J.J. Wang (Jie Jin); M. Schache (Maria); S. Janmahasathian (Sarayut); R.P. Igo Jr. (Robert); J.H. Lass Jr. (Jonathan); E.Y. Chew (Emily); S.K. Iyengar (Sudha); T.G.M.F. Gorgels (Theo); I. Rudan (Igor); C. Hayward (Caroline); A.F. Wright (Alan); O. Polasek (Ozren); Z. Vatavuk (Zoran); J.F. Wilson (James); B. Fleck (Brian); T. Zeller (Tanja); A. Mirshahi (Alireza); C. Müller (Christian); A.G. Uitterlinden (André); F. Rivadeneira Ramirez (Fernando); J.R. Vingerling (Hans); A. Hofman (Albert); B.A. Oostra (Ben); N. Amin (Najaf); A.A.B. Bergen (Arthur); Y.Y. Teo (Yik Ying); J.S. Rahi (Jugnoo); V. Vitart (Veronique); C. Williams (Cathy); P.N. Baird (Paul); T.Y. Wong (Tien); K. Oexle (Konrad); A.F.H. Pfeiffer (Andreas); D.A. Mackey (David); T.L. Young (Terri); C.M. van Duijn (Cock); S-M. Saw (Seang-Mei); J.E. Bailey-Wilson (Joan); D.E. Stambolian (Dwight); C.C.W. Klaver (Caroline); C.J. Hammond (Christopher)

    2013-01-01

    textabstractRefractive error is the most common eye disorder worldwide and is a prominent cause of blindness. Myopia affects over 30% of Western populations and up to 80% of Asians. The CREAM consortium conducted genome-wide meta-analyses, including 37,382 individuals from 27 studies of European

  14. Standards, accuracy, and questions of bias in Rorschach meta-analyses: reply to Wood, Garb, Nezworski, Lilienfeld, and Duke (2015).

    Science.gov (United States)

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

    2015-01-01

    Wood, Garb, Nezworski, Lilienfeld, and Duke (2015) found our systematic review and meta-analyses of 65 Rorschach variables to be accurate and unbiased, and hence removed their previous recommendation for a moratorium on the applied use of the Rorschach. However, Wood et al. (2015) hypothesized that publication bias would exist for 4 Rorschach variables. To test this hypothesis, they replicated our meta-analyses for these 4 variables and added unpublished dissertations to the pool of articles. In the process, they used procedures that contradicted their standards and recommendations for sound Rorschach research, which consistently led to significantly lower effect sizes. In reviewing their meta-analyses, we found numerous methodological errors, data errors, and omitted studies. In contrast to their strict requirements for interrater reliability in the Rorschach meta-analyses of other researchers, they did not report interrater reliability for any of their coding and classification decisions. In addition, many of their conclusions were based on a narrative review of individual studies and post hoc analyses rather than their meta-analytic findings. Finally, we challenge their sole use of dissertations to test publication bias because (a) they failed to reconcile their conclusion that publication bias was present with the analyses we conducted showing its absence, and (b) we found numerous problems with dissertation study quality. In short, one cannot rely on the findings or the conclusions reported in Wood et al.

  15. Methodology and reporting of meta-analyses in the neurosurgical literature.

    Science.gov (United States)

    Klimo, Paul; Thompson, Clinton J; Ragel, Brian T; Boop, Frederick A

    2014-04-01

    Neurosurgeons are inundated with vast amounts of new clinical research on a daily basis, making it difficult and time-consuming to keep up with the latest literature. Meta-analysis is an extension of a systematic review that employs statistical techniques to pool the data from the literature in order to calculate a cumulative effect size. This is done to answer a clearly defined a priori question. Despite their increasing popularity in the neurosurgery literature, meta-analyses have not been scrutinized in terms of reporting and methodology. The authors performed a literature search using PubMed/MEDLINE to locate all meta-analyses that have been published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Accepted checklists for reporting (PRISMA) and methodology (AMSTAR) were applied to each meta-analysis, and the number of items within each checklist that were satisfactorily fulfilled was recorded. The authors sought to answer 4 specific questions: Are meta-analyses improving 1) with time; 2) when the study met their definition of a meta-analysis; 3) when clinicians collaborated with a potential expert in meta-analysis; and 4) when the meta-analysis was the only focus of the paper? Seventy-two meta-analyses were published in the JNS Publishing Group journals and Neurosurgery between 1990 and 2012. The number of published meta-analyses has increased dramatically in the last several years. The most common topics were vascular, and most were based on observational studies. Only 11 papers were prepared using an established checklist. The average AMSTAR and PRISMA scores (proportion of items satisfactorily fulfilled divided by the total number of eligible items in the respective instrument) were 31% and 55%, respectively. Major deficiencies were identified, including the lack of a comprehensive search strategy, study selection and data extraction

  16. Comparison of statistical inferences from the DerSimonian-Laird and alternative random-effects model meta-analyses - an empirical assessment of 920 Cochrane primary outcome meta-analyses.

    Science.gov (United States)

    Thorlund, Kristian; Wetterslev, Jørn; Awad, Tahany; Thabane, Lehana; Gluud, Christian

    2011-12-01

    In random-effects model meta-analysis, the conventional DerSimonian-Laird (DL) estimator typically underestimates the between-trial variance. Alternative variance estimators have been proposed to address this bias. This study aims to empirically compare statistical inferences from random-effects model meta-analyses on the basis of the DL estimator and four alternative estimators, as well as distributional assumptions (normal distribution and t-distribution) about the pooled intervention effect. We evaluated the discrepancies of p-values, 95% confidence intervals (CIs) in statistically significant meta-analyses, and the degree (percentage) of statistical heterogeneity (e.g. I(2)) across 920 Cochrane primary outcome meta-analyses. In total, 414 of the 920 meta-analyses were statistically significant with the DL meta-analysis, and 506 were not. Compared with the DL estimator, the four alternative estimators yielded p-values and CIs that could be interpreted as discordant in up to 11.6% or 6% of the included meta-analyses pending whether a normal distribution or a t-distribution of the intervention effect estimates were assumed. Large discrepancies were observed for the measures of degree of heterogeneity when comparing DL with each of the four alternative estimators. Estimating the degree (percentage) of heterogeneity on the basis of less biased between-trial variance estimators seems preferable to current practice. Disclosing inferential sensitivity of p-values and CIs may also be necessary when borderline significant results have substantial impact on the conclusion. Copyright © 2012 John Wiley & Sons, Ltd.

  17. A journey into a Mediterranean diet and type 2 diabetes: a systematic review with meta-analyses.

    Science.gov (United States)

    Esposito, Katherine; Maiorino, Maria Ida; Bellastella, Giuseppe; Chiodini, Paolo; Panagiotakos, Demosthenes; Giugliano, Dario

    2015-08-10

    To summarise the evidence about the efficacy of a Mediterranean diet on the management of type 2 diabetes and prediabetic states. A systematic review of all meta-analyses and randomised controlled trials (RCTs) that compared the Mediterranean diet with a control diet on the treatment of type 2 diabetes and prediabetic states was conducted. Electronic searches were carried out up to January 2015. Trials were included for meta-analyses if they had a control group treated with another diet, if they were of sufficient duration (at least 6 months), and if they had at least 30 participants in each arm. A random-effect model was used to pool data. Adults with or at risk for type 2 diabetes. Dietary patterns that described themselves as using a 'Mediterranean' dietary pattern. The outcomes were glycaemic control, cardiovascular risk factors and remission from the metabolic syndrome. From 2824 studies, 8 meta-analyses and 5 RCTs were eligible. A 'de novo' meta-analysis of 3 long-term (>6 months) RCTs of the Mediterranean diet and glycaemic control of diabetes favoured the Mediterranean diet as compared with lower fat diets. Another 'de novo' meta-analysis of two long-term RCTs showed a 49% increased probability of remission from the metabolic syndrome. 5 meta-analyses showed a favourable effect of the Mediterranean diet, as compared with other diets, on body weight, total cholesterol and high-density lipoprotein cholesterol. 2 meta-analyses demonstrated that higher adherence to the Mediterranean diet reduced the risk of future diabetes by 19-23%. The Mediterranean diet was associated with better glycaemic control and cardiovascular risk factors than control diets, including a lower fat diet, suggesting that it is suitable for the overall management of type 2 diabetes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data: the PRISMA-IPD Statement.

    Science.gov (United States)

    Stewart, Lesley A; Clarke, Mike; Rovers, Maroeska; Riley, Richard D; Simmonds, Mark; Stewart, Gavin; Tierney, Jayne F

    2015-04-28

    Systematic reviews and meta-analyses of individual participant data (IPD) aim to collect, check, and reanalyze individual-level data from all studies addressing a particular research question and are therefore considered a gold standard approach to evidence synthesis. They are likely to be used with increasing frequency as current initiatives to share clinical trial data gain momentum and may be particularly important in reviewing controversial therapeutic areas. To develop PRISMA-IPD as a stand-alone extension to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Statement, tailored to the specific requirements of reporting systematic reviews and meta-analyses of IPD. Although developed primarily for reviews of randomized trials, many items will apply in other contexts, including reviews of diagnosis and prognosis. Development of PRISMA-IPD followed the EQUATOR Network framework guidance and used the existing standard PRISMA Statement as a starting point to draft additional relevant material. A web-based survey informed discussion at an international workshop that included researchers, clinicians, methodologists experienced in conducting systematic reviews and meta-analyses of IPD, and journal editors. The statement was drafted and iterative refinements were made by the project, advisory, and development groups. The PRISMA-IPD Development Group reached agreement on the PRISMA-IPD checklist and flow diagram by consensus. Compared with standard PRISMA, the PRISMA-IPD checklist includes 3 new items that address (1) methods of checking the integrity of the IPD (such as pattern of randomization, data consistency, baseline imbalance, and missing data), (2) reporting any important issues that emerge, and (3) exploring variation (such as whether certain types of individual benefit more from the intervention than others). A further additional item was created by reorganization of standard PRISMA items relating to interpreting results. Wording

  19. Effects of exercise on anxiety and depression disorders: review of meta- analyses and neurobiological mechanisms.

    Science.gov (United States)

    Wegner, Mirko; Helmich, Ingo; Machado, Sergio; Nardi, Antonio E; Arias-Carrion, Oscar; Budde, Henning

    2014-01-01

    Anxiety and depression are the most frequently diagnosed psychological diseases showing a high co-morbidity. They have a severe impact on the lives of the persons concerned. Many meta-analytical studies suggested a positive anxiolytic and depression-reducing effect of exercise programs. The aim of the present article is to synthesize metaanalyses on the effects of exercise on anxiety and depression and to describe average effect sizes. For this purpose 37 meta-analyses were included reporting 50 effect sizes for anxiety scores of 42,264 participants and depression scores of 48,207 persons. The average documented anxiolytic effect of exercise in these reviews was small, 0.34. In contrast, the effect of exercise on depression was significantly higher and at a moderate level, 0.56. Data of randomized controlled trials suggest higher sizes for the effect of exercise on anxiety and depression leading to increases up to moderate and large effects, respectively. Additionally, exercise seems to be more beneficial for patients compared to participants within a non-clinical, normal range of psychological disease. Especially for the effect of exercise on anxiety, more high quality meta-analyses of randomized controlled trials are needed. Finally, possible neurobiological explanations are suggested for the positive effect of exercise on psychological disorders like anxiety and depression.

  20. 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

  1. Effect of reporting bias on meta-analyses of drug trials

    DEFF Research Database (Denmark)

    Hart, Beth; Lundh, Andreas; Bero, Lisa

    2012-01-01

    To investigate the effect of including unpublished trial outcome data obtained from the Food and Drug Administration (FDA) on the results of meta-analyses of drug trials.......To investigate the effect of including unpublished trial outcome data obtained from the Food and Drug Administration (FDA) on the results of meta-analyses of drug trials....

  2. Meta-analyses of the 5-HTTLPR polymorphisms and post-traumatic stress disorder.

    Directory of Open Access Journals (Sweden)

    Fernando Navarro-Mateu

    Full Text Available OBJECTIVE: To conduct a meta-analysis of all published genetic association studies of 5-HTTLPR polymorphisms performed in PTSD cases. METHODS DATA SOURCES: Potential studies were identified through PubMed/MEDLINE, EMBASE, Web of Science databases (Web of Knowledge, WoK, PsychINFO, PsychArticles and HuGeNet (Human Genome Epidemiology Network up until December 2011. STUDY SELECTION: Published observational studies reporting genotype or allele frequencies of this genetic factor in PTSD cases and in non-PTSD controls were all considered eligible for inclusion in this systematic review. DATA EXTRACTION: Two reviewers selected studies for possible inclusion and extracted data independently following a standardized protocol. STATISTICAL ANALYSIS: A biallelic and a triallelic meta-analysis, including the total S and S' frequencies, the dominant (S+/LL and S'+/L'L' and the recessive model (SS/L+ and S'S'/L'+, was performed with a random-effect model to calculate the pooled OR and its corresponding 95% CI. Forest plots and Cochran's Q-Statistic and I(2 index were calculated to check for heterogeneity. Subgroup analyses and meta-regression were carried out to analyze potential moderators. Publication bias and quality of reporting were also analyzed. RESULTS: 13 studies met our inclusion criteria, providing a total sample of 1874 patients with PTSD and 7785 controls in the biallelic meta-analyses and 627 and 3524, respectively, in the triallelic. None of the meta-analyses showed evidence of an association between 5-HTTLPR and PTSD but several characteristics (exposure to the same principal stressor for PTSD cases and controls, adjustment for potential confounding variables, blind assessment, study design, type of PTSD, ethnic distribution and Total Quality Score influenced the results in subgroup analyses and meta-regression. There was no evidence of potential publication bias. CONCLUSIONS: Current evidence does not support a direct effect of 5-HTTLPR

  3. Retrieval of Individual Participant Data for Exercise Meta-Analyses May Not Be Worth the Time and Effort.

    Science.gov (United States)

    Kelley, George A; Kelley, Kristi S

    2016-01-01

    While individual participant data (IPD) meta-analyses are considered the gold standard for meta-analysis, the feasibility of obtaining IPD may be problematic. Using data from a previous meta-analysis of 29 studies on exercise in adults with arthritis and other rheumatic diseases, the percentage of studies in which useable IPD was provided was calculated. Eight of 29 authors (28%, 95% CI = 11% to 44%) provided IPD. Using logistic regression, neither year of publication (odds ratio = 1.05, 95% CI = 0.90 to 1.27, p = 0.58) nor country (odds ratio = 1.36, 95% CI = 0.20 to 10.9, p = 1.00) was significantly associated with the obtainment of IPD. The retrieval of IPD for exercise meta-analyses may not be worth the time and effort. However, further research is needed before any final recommendations can be made.

  4. Measures of single arm outcome in meta-analyses of rare events in the presence of competing risks.

    Science.gov (United States)

    Andreano, Anita; Rebora, Paola; Valsecchi, Maria Grazia

    2015-07-01

    When performing single arm meta-analyses of rare events in small populations, if the outcome of interest is incidence, it is not uncommon to have at least one study with zero events, especially in the presence of competing risks. In this paper, we address the problem of how to include studies with zero events in inverse variance meta-analyses when individual patient data are not available, going beyond the naïve approach of not including the study or the use of a continuity correction. The proposed solution is the arcsine transformation of the crude cumulative incidence as its approximate variance, which is inversely proportional to the sample size, can be calculated also for studies with a zero estimate. As an alternative, generalized linear mixed models (GLMM) can be used. Simulations were performed to compare the results from inverse variance method meta-analyses of the arcsine transformed cumulative incidence to those obtained from meta-analyses of the cumulative incidence itself and of the logit transformation of the cumulative incidence. The comparisons have been carried out for different scenarios of heterogeneity, incidence, and censoring and for competing and not competing risks. The arcsine transformation showed the smallest bias and the highest coverage among models assuming within study normality. At the same time, the GLMM model had the best performance at very low incidences. The proposed method was applied to the clinical context that motivated this work, i.e. a meta-analysis of 5-year crude cumulative incidence of central nervous system recurrences in children treated for acute lymphoblastic leukemia.

  5. Vitamin B12, Folate, Homocysteine, and Bone Health in Adults and Elderly People: A Systematic Review with Meta-Analyses

    Directory of Open Access Journals (Sweden)

    J. P. van Wijngaarden

    2013-01-01

    Full Text Available Elevated homocysteine levels and low vitamin B12 and folate levels have been associated with deteriorated bone health. This systematic literature review with dose-response meta-analyses summarizes the available scientific evidence on associations of vitamin B12, folate, and homocysteine status with fractures and bone mineral density (BMD. Twenty-seven eligible cross-sectional (n=14 and prospective (n=13 observational studies and one RCT were identified. Meta-analysis on four prospective studies including 7475 people showed a modest decrease in fracture risk of 4% per 50 pmol/L increase in vitamin B12 levels, which was borderline significant (RR = 0.96, 95% CI = 0.92 to 1.00. Meta-analysis of eight studies including 11511 people showed an increased fracture risk of 4% per μmol/L increase in homocysteine concentration (RR = 1.04, 95% CI = 1.02 to 1.07. We could not draw a conclusion regarding folate levels and fracture risk, as too few studies investigated this association. Meta-analyses regarding vitamin B12, folate and homocysteine levels, and BMD were possible in female populations only and showed no associations. Results from studies regarding BMD that could not be included in the meta-analyses were not univocal.

  6. Effects of Exercise in the Treatment of Overweight and Obese Children and Adolescents: A Systematic Review of Meta-Analyses

    Directory of Open Access Journals (Sweden)

    George A. Kelley

    2013-01-01

    Full Text Available Purpose. Conduct a systematic review of previous meta-analyses addressing the effects of exercise in the treatment of overweight and obese children and adolescents. Methods. Previous meta-analyses of randomized controlled exercise trials that assessed adiposity in overweight and obese children and adolescents were included by searching nine electronic databases and cross-referencing from retrieved studies. Methodological quality was assessed using the Assessment of Multiple Systematic Reviews (AMSTAR Instrument. The alpha level for statistical significance was set at P≤0.05. Results. Of the 308 studies reviewed, two aggregate data meta-analyses representing 14 and 17 studies and 481 and 701 boys and girls met all eligibility criteria. Methodological quality was 64% and 73%. For both studies, statistically significant reductions in percent body fat were observed (P=0.006 and P<0.00001. The number-needed-to treat (NNT was 4 and 3 with an estimated 24.5 and 31.5 million overweight and obese children in the world potentially benefitting, 2.8 and 3.6 million in the US. No other measures of adiposity (BMI-related measures, body weight, and central obesity were statistically significant. Conclusions. Exercise is efficacious for reducing percent body fat in overweight and obese children and adolescents. Insufficient evidence exists to suggest that exercise reduces other measures of adiposity.

  7. Sleep and attachment in early childhood: a series of meta-analyses.

    Science.gov (United States)

    Simard, Valérie; Chevalier, Valérie; Bédard, Marie-Michèle

    2017-06-01

    Empirical findings regarding the association between child attachment and sleep have been inconsistent. The objectives of this series of meta-analyses were to assess the size of the association between child sleep and attachment and to examine whether study methodology (attachment measure, sleep measure) and age moderate this association. Sixteen studies (2783 children aged from 6 to 38 months) were included. Significant associations were found between attachment security and sleep efficiency (r = .18) and attachment resistance and sleep problems (r = .18). There were significant moderator effects of sleep measure and age of the child, with the size of the association between sleep and attachment security increasing with age (R(2) analog = .67). Inconsistent findings are likely due to inter-study variabilities in methodology and to a developmental effect on the sleep-attachment association.

  8. The Reporting Quality of Systematic Reviews and Meta-Analyses in Industrial and Organizational Psychology: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Naomi Schalken

    2017-08-01

    Full Text Available Objective: The goal of this systematic review was to examine the reporting quality of the method section of quantitative systematic reviews and meta-analyses from 2009 to 2016 in the field of industrial and organizational psychology with the help of the Meta-Analysis Reporting Standards (MARS, and to update previous research, such as the study of Aytug et al. (2012 and Dieckmann et al. (2009.Methods: A systematic search for quantitative systematic reviews and meta-analyses was conducted in the top 10 journals in the field of industrial and organizational psychology between January 2009 and April 2016. Data were extracted on study characteristics and items of the method section of MARS. A cross-classified multilevel model was analyzed, to test whether publication year and journal impact factor (JIF were associated with the reporting quality scores of articles.Results: Compliance with MARS in the method section was generally inadequate in the random sample of 120 articles. Variation existed in the reporting of items. There were no significant effects of publication year and journal impact factor (JIF on the reporting quality scores of articles.Conclusions: The reporting quality in the method section of systematic reviews and meta-analyses was still insufficient, therefore we recommend researchers to improve the reporting in their articles by using reporting standards like MARS.

  9. Comprehensive research synopsis and systematic meta-analyses in Parkinson's disease genetics: The PDGene database.

    Directory of Open Access Journals (Sweden)

    Christina M Lill

    Full Text Available More than 800 published genetic association studies have implicated dozens of potential risk loci in Parkinson's disease (PD. To facilitate the interpretation of these findings, we have created a dedicated online resource, PDGene, that comprehensively collects and meta-analyzes all published studies in the field. A systematic literature screen of -27,000 articles yielded 828 eligible articles from which relevant data were extracted. In addition, individual-level data from three publicly available genome-wide association studies (GWAS were obtained and subjected to genotype imputation and analysis. Overall, we performed meta-analyses on more than seven million polymorphisms originating either from GWAS datasets and/or from smaller scale PD association studies. Meta-analyses on 147 SNPs were supplemented by unpublished GWAS data from up to 16,452 PD cases and 48,810 controls. Eleven loci showed genome-wide significant (P < 5 × 10(-8 association with disease risk: BST1, CCDC62/HIP1R, DGKQ/GAK, GBA, LRRK2, MAPT, MCCC1/LAMP3, PARK16, SNCA, STK39, and SYT11/RAB25. In addition, we identified novel evidence for genome-wide significant association with a polymorphism in ITGA8 (rs7077361, OR 0.88, P  =  1.3 × 10(-8. All meta-analysis results are freely available on a dedicated online database (www.pdgene.org, which is cross-linked with a customized track on the UCSC Genome Browser. Our study provides an exhaustive and up-to-date summary of the status of PD genetics research that can be readily scaled to include the results of future large-scale genetics projects, including next-generation sequencing studies.

  10. Systematic review with dose-response meta-analyses between vitamin B-12 intake and European Micronutrient Recommendations Aligned’s prioritized biomarkers of vitamin B-12 including randomized controlled trials and observational studies in adults and elderly persons

    NARCIS (Netherlands)

    Dullemeijer, C.; Souverein, O.W.; Doets, E.L.; Voet, van der H.; Wijngaarden, van J.P.; Boer, de W.J.; Plada, M.; Dhonukshe-Rutten, R.A.M.; Veld, in 't P.H.; Cavelaars, A.J.E.M.; Groot, de C.P.G.M.; Veer, van 't P.

    2013-01-01

    Background: Many randomized controlled trials (RCTs) and observational studies have provided information on the association between vitamin B-12 intake and biomarkers. The use of these data to estimate dose-response relations provides a useful means to summarize the body of evidence. Objective: We s

  11. Combining scores from different patient reported outcome measures in meta-analyses: when is it justified?

    Directory of Open Access Journals (Sweden)

    Guyatt Gordon H

    2006-12-01

    Full Text Available Abstract Background Combining outcomes and the use of standardized effect measures such as effect size and standardized response mean across instruments allows more comprehensive meta-analyses and should avoid selection bias. However, such analysis ideally requires that the instruments correlate strongly and that the underlying assumption of similar responsiveness is fulfilled. The aim of the study was to assess the correlation between two widely used health-related quality of life instruments for patients with chronic obstructive pulmonary disease and to compare the instruments' responsiveness on a study level. Methods We systematically identified all longitudinal studies that used both the Chronic Respiratory Questionnaire (CRQ and the St. George's Respiratory Questionnaire (SGRQ through electronic searches of MEDLINE, EMBASE, CENTRAL and PubMed. We assessed the correlation between CRQ (scale 1 – 7 and SGRQ (scale 1 – 100 change scores and compared responsiveness of the two instruments by comparing standardized response means (change scores divided by their standard deviation. Results We identified 15 studies with 23 patient groups. CRQ change scores ranged from -0.19 to 1.87 (median 0.35, IQR 0.14–0.68 and from -16.00 to 3.00 (median -3.00, IQR -4.73–0.25 for SGRQ change scores. The correlation between CRQ and SGRQ change scores was 0.88. Standardized response means of the CRQ (median 0.51, IQR 0.19–0.98 were significantly higher (p Conclusion Investigators should be cautious about pooling the results from different instruments in meta-analysis even if they appear to measure similar constructs. Despite high correlation in changes scores, responsiveness of instruments may differ substantially and could lead to important between-study heterogeneity and biased meta-analyses.

  12. Assessing the perceived quality of brachial artery Flow Mediated Dilation studies for inclusion in meta-analyses and systematic reviews: Description of data employed in the development of a scoring ;tool based on currently accepted guidelines

    Directory of Open Access Journals (Sweden)

    Arno Greyling

    2016-09-01

    Full Text Available Brachial artery Flow Mediated Dilation (FMD is widely used as a non-invasive measure of endothelial function. Adherence to expert consensus guidelines on FMD measurement has been found to be of vital importance to obtain reproducible data. This article lists the literature data which was considered in the development of a tool to aid in the objective judgement of the extent to which published studies adhered to expert guidelines for FMD measurement. Application of this tool in a systematic review of FMD studies (http://dx.doi.org/10.1016/j.atherosclerosis.2016.03.011 (Greyling et al., 2016 [1] indicated that adherence to expert consensus guidelines is strongly correlated to the reproducibility of FMD data.

  13. Effects of respiratory muscle training on performance in athletes: a systematic review with meta-analyses.

    Science.gov (United States)

    HajGhanbari, Bahareh; Yamabayashi, Cristiane; Buna, Teryn R; Coelho, Jonathan D; Freedman, Kyle D; Morton, Trevor A; Palmer, Sheree A; Toy, Melissa A; Walsh, Cody; Sheel, A William; Reid, W Darlene

    2013-06-01

    The purpose of this study was to perform a systematic review to determine if respiratory muscle training (RMT) improves sport performance and respiratory muscle strength and endurance. Methodology followed the Cochrane Collaboration protocol. MEDLINE, CINAHL, SPORTDiscus, PEDro, EMBASE, EBM reviews, and COCHRANE electronic databases were searched until July 2011. Articles were included if: (a) participants were athletes; (b) RMT was compared with sham or control in a randomized controlled design and included outcomes of respiratory muscle and sport performance; and (d) published in English. Quality assessment using PEDro and data abstraction was performed by 2 authors. Outcomes evaluated were measures of sport performance, exercise capacity, spirometry, and respiratory muscle strength and endurance. Meta-analyses were performed on outcomes reported in 2 or more papers. Results of this systematic review revealed that of the 6,923 citations retrieved from the search strategy, 21 met the inclusion criteria. Meta-analyses demonstrated a significant positive effect of RMT on sport performance outcomes of time trials, exercise endurance time, and repetitions on Yo-Yo tests. Inspiratory muscle strength and endurance improved in most studies, which in part, was dependent on the type of RMT employed. Determination of the type of athlete that may benefit most from RMT was limited by small sample sizes, differing RMT protocols, and differences in outcome measures across studies. In conclusion, RMT can improve sport performance. Closer attention to matching the ventilatory demands of RMT to those required during athletic competition and more aggressive progression of training intensity may show greater improvements in future studies.

  14. Laparoscopic cholecystectomy under neuraxial anesthesia compared with general anesthesia: Systematic review and meta-analyses.

    Science.gov (United States)

    Longo, Marcelo A; Cavalheiro, Bárbara T; de Oliveira Filho, Getúlio R

    2017-09-01

    Pneumoperitoneum during laparoscopic cholecystectomy (LC) can cause hypercapnia, hypoxemia, hemodynamic changes and shoulder pain. General anesthesia (GA) enables the control of intraoperative pain and ventilation. The need for GA has been questioned by studies suggesting that neuraxial anesthesia (NA) is adequate for LC. To quantify the prevalence of intraoperative pain and to verify whether evidence on the maintenance of ventilation, circulation and surgical anesthesia during NA compared with GA is consistent. Systematic review with meta-analyses. Anesthesia for laparoscopic cholecystectomy. We searched Medline, Cochrane and EBSCO databases up to 2016 for randomized controlled trials that compared LC in the two groups under study, neuraxial (subarachnoid or epidural) and general anesthesia. The primary outcome was the prevalence of intraoperative pain referred to the shoulder in the NA group. Hemodynamic and respiratory outcomes and adverse effects in both groups were also collected. Eleven comparative studies were considered eligible. The pooled prevalence of shoulder pain was 25%. Intraoperative hypotension and bradycardia occurred more frequently in patients who received NA, with a risk ratio of 4.61 (95% confidence interval [CI] 1.70-12.48, p=0.003) and 6.67 (95% CI 2.02-21.96, p=0.002), respectively. Postoperative nausea and vomiting was more prevalent in patients who submitted to GA. The prevalence of postoperative urinary retention did not differ between the techniques. Postoperative headache was more prevalent in patients who received NA, while the postoperative pain intensity was lower in this group. Performing meta-analyses on hypertension, hypercapnia and hypoxemia was not possible. NA as sole anesthetic technique, although feasible for LC, was associated with intraoperative pain referred to the shoulder, required anesthetic conversion in 3.4% of the cases and did not demonstrate evidence of respiratory benefits for patients with normal pulmonary

  15. Meta-analyses of associations between interleukin-10 polymorphisms and susceptibility to recurrent pregnancy loss.

    Science.gov (United States)

    Lee, Young Ho; Kim, Jae-Hoon; Song, Gwan Gyu

    2016-05-01

    The aim of this study was to investigate whether interleukin-10 (IL-10) polymorphisms are associated with susceptibility to recurrent pregnancy loss (RPL). We conducted a literature search using the PubMed and EMBASE databases and performed meta-analyses on the associations between IL-10 -1082 G/A, -819 C/T, and -592 C/A polymorphisms and RPL, using fixed- or random-effects models. A total of 15 papers involving 1858 RPL patients and 1949 controls were considered in this study. Meta-analysis of IL-10 -1082 G/A polymorphism revealed no association between RPL and the IL-10 -1082 G allele (OR=0.999, 95% CI=0.815-1.223, p=0.989). However, meta-analysis of IL-10 -819 C/T polymorphism in all study subjects revealed an association between RPL and the IL-10 -819 C allele (OR=0.680, 95% CI=0.498-0.927, p=0.015). Stratification by ethnicity indicated an association between the IL-10 -819 C allele and RPL in the Asian group (OR=0.421, 95% CI=0.226-0.783, p=0.006), but not in the Caucasian and Arab groups (OR=1.053, 95% CI=0.218-5.077, p=0.949, and OR=0.800, 95% CI=0.606-1.081, p=0.152, respectively). Furthermore, a relationship between the IL-10 -592 C allele and RPL was identified in the Asian group (OR=0.763, 95% CI=0.633-0.919, p=0.004), but not in the Caucasian and Arab groups. The meta-analyses demonstrate that IL-10 -819 C/T and -592 C/A polymorphisms are associated with RPL susceptibility in Asian women, but not in the Caucasian and Arab populations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Meta-Analyses of the Associations of Respiratory Health Effectswith Dampness and Mold in Homes

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J.; Lei-Gomez, Quanhong; Mendell, Mark J.

    2006-01-01

    The Institute of Medicine (IOM) of the National Academy of Sciences recently completed a critical review of the scientific literature pertaining to the association of indoor dampness and mold contamination with adverse health effects. In this paper, we report the results of quantitative meta-analysis of the studies reviewed in the IOM report. We developed point estimates and confidence intervals (CIs) to summarize the association of several respiratory and asthma-related health outcomes with the presence of dampness and mold in homes. The odds ratios and confidence intervals from the original studies were transformed to the log scale and random effect models were applied to the log odds ratios and their variance. Models were constructed both accounting for the correlation between multiple results within the studies analyzed and ignoring such potential correlation. Central estimates of ORs for the health outcomes ranged from 1.32 to 2.10, with most central estimates between 1.3 and 1.8. Confidence intervals (95%) excluded unity except in two of 28 instances, and in most cases the lower bound of the CI exceeded 1.2. In general, the two meta-analysis methods produced similar estimates for ORs and CIs. Based on the results of the meta-analyses, building dampness and mold are associated with approximately 30% to 80% increases in a variety of respiratory and asthma-related health outcomes. The results of these meta-analyses reinforce the IOM's recommendation that actions be taken to prevent and reduce building dampness problems.

  17. 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...

  18. Benefits of Exercise Training For Computer-Based Staff: A Meta Analyses

    Directory of Open Access Journals (Sweden)

    Mothna Mohammed

    2017-04-01

    Full Text Available Background: Office workers sit down to work for approximately 8 hours a day and, as a result, many of them do not have enough time for any form of physical exercise. This can lead to musculoskeletal discomforts, especially low back pain and recently, many researchers focused on home/office-based exercise training for prevention/treatment of low back pain among this population. Objective: This Meta analyses paper tried to discuss about the latest suggested exercises for the office workers based on the mechanisms and theories behind low back pain among office workers. Method: In this Meta analyses the author tried to collect relevant papers which were published previously on the subject. Google Scholar, Scopus, and PubMed were used as sources to find the articles. Only articles that were published using the same methodology, including office workers, musculoskeletal discomforts, low back pain, and exercise training keywords, were selected. Studies that failed to report sufficient sample statistics, or lacked a substantial review of past academic scholarship and/or clear methodologies, were excluded. Results: Limited evidence regarding the prevention of, and treatment methods for, musculoskeletal discomfort, especially those in the low back, among office workers, is available. The findings showed that training exercises had a significant effect (p<0.05 on low back pain discomfort scores and decreased pain levels in response to office-based exercise training. Conclusion: Office-based exercise training can affect pain/discomfort scores among office workers through positive effects on flexibility and strength of muscles. As such, it should be suggested to occupational therapists as a practical way for the treatment/prevention of low back pain among office workers.

  19. Is surgical intervention more effective than non-surgical treatment for acute Achilles tendon rupture? A systematic review of overlapping meta-analyses.

    Science.gov (United States)

    Wu, Yaohong; Lin, Linghan; Li, Hao; Zhao, Yachao; Liu, Longgang; Jia, Zhiwei; Wang, Deli; He, Qing; Ruan, Dike

    2016-12-01

    There is discordance in the results from meta-analyses on surgical versus non-surgical treatment for acute Achilles tendon rupture. We systematically reviewed the overlapping meta-analyses on this topic to provide information that will be helpful to decision makers when selecting treatments based on the current best available evidence. We comprehensively searched multiple databases for systematic reviews that compared surgical and non-surgical treatments for acute Achilles tendon rupture. We only included meta-analyses that comprised randomized controlled trials (RCTs). The methodological quality and extracted data were assessed. The meta-analysis that offered the best evidence was ascertained with the Jadad decision algorithm. Nine meta-analyses were included in our study and all of them included RCTs with Level-II evidence. Assessment of Multiple Systematic Reviews (AMSTAR) scores ranged from 5 to 10 (median 7). The Jadad decision algorithm was used to select a high-quality meta-analysis with more RCTs. The results from this study showed that when functional rehabilitation was used, non-surgical intervention was similar to surgical treatment regarding the incidence of range of motion, rerupture, calf circumference and functional outcomes, and the incidence of other complications was reduced. Non-surgical intervention significantly increased the rerupture rate if functional rehabilitation was not considered. The findings of meta-analyses regarding surgical versus non-surgical treatment for acute Achilles tendon rupture are inconsistent. According to this systematic review of overlapping meta-analyses, the current best available evidence suggests that centers offering functional rehabilitation may prefer non-surgical intervention. Surgical treatment may be preferred at centers that do not have functional rehabilitation. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  20. Reported methodologic quality and discrepancies between large and small randomized trials in meta-analyses

    DEFF Research Database (Denmark)

    Kjaergard, L L; Villumsen, J; Gluud, C

    2001-01-01

    To explore whether reported methodologic quality affects estimated intervention effects in randomized trials and contributes to discrepancies between the results of large randomized trials and small randomized trials in meta-analyses....

  1. Can trial sequential monitoring boundaries reduce spurious inferences from meta-analyses?

    DEFF Research Database (Denmark)

    Thorlund, Kristian; Devereaux, P J; Wetterslev, Jørn

    2008-01-01

    -analyses after each included trial and evaluated their results using a conventional statistical criterion (alpha = 0.05) and two-sided Lan-DeMets monitoring boundaries. We examined the proportion of false positive results and important inaccuracies in estimates of treatment effects that resulted from the two...... approaches. RESULTS: Using the random-effects model and final data, 12 of the meta-analyses yielded P > alpha = 0.05, and 21 yielded P alpha = 0.05. The monitoring boundaries eliminated all false positives. Important inaccuracies in estimates were observed in 6 out of 21 meta-analyses using the conventional...... a chance finding (i.e. applying trial sequential monitoring boundaries). METHODS: We analysed 33 meta-analyses with a sufficient IS to detect a treatment effect of 15% relative risk reduction (RRR). We successively monitored the results of the meta-analyses by generating interim cumulative meta...

  2. Critical appraisal of meta-analyses: an introductory guide for the practicing surgeon

    Directory of Open Access Journals (Sweden)

    McCall Jonathan

    2009-07-01

    Full Text Available Abstract Meta-analyses are an essential tool of clinical research. Meta-analyses of individual randomized controlled trials frequently constitute the highest possible level of scientific evidence for a given research question and allow surgeons to rapidly gain a comprehensive understanding of an important clinical issue. Moreover, meta-analyses often serve as cornerstones for evidence-based surgery, treatment guidelines, and knowledge transfer. Given the importance of meta-analyses to the medical (and surgical knowledge base, it is of cardinal importance that surgeons have a basic grasp of the principles that guide a high-quality meta-analysis, and be able to weigh objectively the advantages and potential pitfalls of this clinical research tool. Unfortunately, surgeons are often ill-prepared to successfully conduct, critically appraise, and correctly interpret meta-analyses. The objective of this educational review is to provide surgeons with a brief introductory overview of the knowledge and skills required for understanding and critically appraising surgical meta-analyses as well as assessing their implications for their own surgical practice.

  3. The current state of intermittent intraoperative neural monitoring for prevention of recurrent laryngeal nerve injury during thyroidectomy: a PRISMA-compliant systematic review of overlapping meta-analyses.

    Science.gov (United States)

    Henry, Brandon Michael; Graves, Matthew J; Vikse, Jens; Sanna, Beatrice; Pękala, Przemysław A; Walocha, Jerzy A; Barczyński, Marcin; Tomaszewski, Krzysztof A

    2017-06-01

    Recurrent laryngeal nerve (RLN) injury is one of the most common and detrimental complications following thyroidectomy. Intermittent intraoperative nerve monitoring (I-IONM) has been proposed to reduce prevalence of RLN injury following thyroidectomy and has gained increasing acceptance in recent years. A comprehensive database search was performed, and data from eligible meta-analyses meeting the inclusion criteria were extracted. Transient, permanent, and overall RLN injuries were the primary outcome measures. Quality assessment via AMSTAR, heterogeneity appraisal, and selection of best evidence was performed via a Jadad algorithm. Eight meta-analyses met the inclusion criteria. Meta-analyses included between 6 and 23 original studies each. Via utilization of the Jadad algorithm, the selection of best evidence resulted in choosing of Pisanu et al. (Surg Res 188:152-161, 2014). Five out of eight meta-analyses demonstrated non-significant (p > 0.05) RLN injury reduction with the use of I-IONM versus nerve visualization alone. To date, I-IONM has not achieved a significant level of RLN injury reduction as shown by the meta-analysis conducted by Pisanu et al. (Surg Res 188:152-161, 2014). However, most recent developments of IONM technology including continuous vagal IONM and concept of staged thyroidectomy in case of loss of signal on the first side in order to prevent bilateral RLN injury may provide additional benefits which were out of the scope of this study and need to be assessed in further prospective multicenter trials.

  4. The link between genetic variation and variability in vaccine responses: systematic review and meta-analyses.

    Science.gov (United States)

    Posteraro, Brunella; Pastorino, Roberta; Di Giannantonio, Paolo; Ianuale, Carolina; Amore, Rosarita; Ricciardi, Walter; Boccia, Stefania

    2014-03-26

    Although immune response to vaccines can be influenced by several parameters, human genetic variations are thought to strongly influence the variability in vaccine responsiveness. Systematic reviews and meta-analyses are needed to clarify the genetic contribution to this variability, which may affect the efficacy of existing vaccines. We performed a systematic literature search to identify all studies describing the associations of allelic variants or single nucleotide polymorphisms in immune response genes with vaccine responses until July 2013. The studies fulfilling inclusion criteria were meta-analyzed. Thirteen studies (11,686 subjects) evaluated the associations of human leukocyte antigen (HLA) and other immunity gene variations with the responses to single vaccines, including MMR-II (measles and rubella virus), HepB (hepatitis virus), influenza virus, and MenC (serogroup C meningococcus) vaccines. Seven HLA genetic variants were included in the meta-analyses. The pooled ORs showed that DRB1*07 (2.46 [95% CI=1.60-3.77]; P for heterogeneity=0.117; I(2)=49.1%), DQA1*02:01 (2.21 [95% CI=1.22-4.00]; P for heterogeneity=0.995; I(2)=0.0%), DQB1*02:01 (2.03 [95% CI=1.35-3.07]; P for heterogeneity=0.449; I(2)=0.0%), and DQB1*03:03 (3.31 [95% CI=1.12-9.78]; P for heterogeneity=0.188; I(2)=42.4%) were associated with a significant decrease of antibody responses to MMR-II, HepB, and influenza vaccines. The pooled ORs showed that DRB1*13 (0.52 [95% CI=0.32-0.84]; P for heterogeneity=0.001; I(2)=85.1%) and DRB1*13:01 (0.19 [95% CI=0.06-0.58]; P for heterogeneity=0.367; I(2)=0.0%) were associated with a significant increase of antibody responses to the above vaccines. While our findings reinforce the concept that individuals with a particular HLA allelic composition are more likely to respond efficiently to vaccines, future studies should be encouraged to further elucidate the link between genetic variation and variability of the human immune response to vaccines

  5. Publication Bias and Nonreporting Found in Majority of Systematic Reviews and Meta-analyses in Anesthesiology Journals.

    Science.gov (United States)

    Hedin, Riley J; Umberham, Blake A; Detweiler, Byron N; Kollmorgen, Lauren; Vassar, Matt

    2016-10-01

    Systematic reviews and meta-analyses are used by clinicians to derive treatment guidelines and make resource allocation decisions in anesthesiology. One cause for concern with such reviews is the possibility that results from unpublished trials are not represented in the review findings or data synthesis. This problem, known as publication bias, results when studies reporting statistically nonsignificant findings are left unpublished and, therefore, not included in meta-analyses when estimating a pooled treatment effect. In turn, publication bias may lead to skewed results with overestimated effect sizes. The primary objective of this study is to determine the extent to which evaluations for publication bias are conducted by systematic reviewers in highly ranked anesthesiology journals and which practices reviewers use to mitigate publication bias. The secondary objective of this study is to conduct publication bias analyses on the meta-analyses that did not perform these assessments and examine the adjusted pooled effect estimates after accounting for publication bias. This study considered meta-analyses and systematic reviews from 5 peer-reviewed anesthesia journals from 2007 through 2015. A PubMed search was conducted, and full-text systematic reviews that fit inclusion criteria were downloaded and coded independently by 2 authors. Coding was then validated, and disagreements were settled by consensus. In total, 207 systematic reviews were included for analysis. In addition, publication bias evaluation was performed for 25 systematic reviews that did not do so originally. We used Egger regression, Duval and Tweedie trim and fill, and funnel plots for these analyses. Fifty-five percent (n = 114) of the reviews discussed publication bias, and 43% (n = 89) of the reviews evaluated publication bias. Funnel plots and Egger regression were the most common methods for evaluating publication bias. Publication bias was reported in 34 reviews (16%). Thirty-six of the 45

  6. Monounsaturated Fatty Acids and Risk of Cardiovascular Disease: Synopsis of the Evidence Available from Systematic Reviews and Meta-Analyses

    Directory of Open Access Journals (Sweden)

    Georg Hoffmann

    2012-12-01

    Full Text Available No dietary recommendations for monounsaturated fatty acids (MUFA are given by the National Institute of Medicine, the United States Department of Agriculture, European Food and Safety Authority and the American Diabetes Association. In contrast, the Academy of Nutrition and Dietetics, and the Canadian Dietetic Association both promote <25% MUFA of daily total energy consumption, while the American Heart Association sets a limit of 20% MUFA in their respective guidelines. The present review summarizes systematic reviews and meta-analyses of randomized controlled trials and cohort studies investigating the effects of MUFA on cardiovascular and diabetic risk factors, cardiovascular events and cardiovascular death. Electronic database Medline was searched for systematic reviews and meta-analyses using “monounsaturated fatty acids”, “monounsaturated fat”, and “dietary fat” as search terms with no restriction to calendar date or language. Reference lists and clinical guidelines were searched as well. Sixteen relevant papers were identified. Several studies indicated an increase of HDL-cholesterol and a corresponding decrease in triacylglycerols following a MUFA-rich diet. The effects on total and LDL-cholesterol appeared not consistent, but no detrimental effects on blood lipids were observed. Values for systolic and diastolic blood pressure were found to be reduced both during short- and long-term protocols using high amounts of MUFA as compared to low-MUFA diets. In type 2 diabetic subjects, MUFA exerted a hypoglycemic effect and reduced glycosylated hemoglobin in the long term. Data from meta-analyses exploring evidence from long-term prospective cohort studies provide ambiguous results with respect to the effects of MUFA on risk of coronary heart disease (CHD. One meta-analysis reported an increase in CHD events, however, most meta-analyses observed a lesser number of cases in participants subjected to a high-MUFA protocol. Although no

  7. HOW HEALTHY IS THE BEHAVIOR OF YOUNG ATHLETES? A SYSTEMATIC LITERATURE REVIEW AND META-ANALYSES

    Directory of Open Access Journals (Sweden)

    Katharina Diehl

    2012-06-01

    Full Text Available Participation in sports during adolescence is considered a healthy behavior. The extent to which adolescent athletes engage in other healthful (or risky behaviors is less clear, however. We conducted a systematic literature review following the PRISMA Statement to assess the frequency of risky behaviors among athletes in this age group. We searched the PubMed, PsycINFO and SCA Sociological Abstracts databases for observational studies published in English over the last twenty years on the frequency of selected risk behaviors (alcohol consumption, smoking behavior, use of illicit drugs, unhealthy nutrition, and doping in adolescent athletes. Two independent reviewers selected articles following the PRISMA Statement. Behavior frequency was assessed as was comparability of study design and methods. When possible, meta- analyses were performed using data from subgroups of studies in which operational indicators were comparable. Seventy-eight articles met eligibility criteria. Although report of risky behaviors varied across studies, we observed overall, that studies tend to report higher alcohol use, less smoking, less recreational drug use, and more smokeless tobacco use in (high-involved athletes. Considerable heterogeneity was noted in study design, definition of target groups and use of operational indicators (I² ranged from 93.2% to 100%. Especially the higher prevalence of using alcohol and smokeless tobacco needs more attention in interventions targeted to this group. Overall, greater consensus on methods used to assess risky behaviors in adolescent athletes

  8. Systematic review and meta-analyses of psychosocial interventions for veterans of the military

    Directory of Open Access Journals (Sweden)

    Neil J. Kitchiner

    2012-12-01

    Full Text Available Background: The efficacy of psychosocial therapies for common mental health disorders in veterans is unclear and requires further examination. Method: Systematic review and meta-analyses of randomised controlled trials (RCTs. Twenty databases were searched. Studies were included if they reported a psychosocial intervention designed to treat or reduce common mental health symptoms in veterans identified as being symptomatic at the time they entered the study. Studies of substance dependency disorders and psychosis were excluded. Eligible studies were assessed against methodological quality criteria and data were extracted and analysed. Results: Twenty-nine RCTs were identified. There was evidence for the use of trauma-focused therapies for post-traumatic stress disorder (PTSD and some evidence for psychological interventions in the treatment of borderline personality disorder, depression, insomnia, and panic disorder co-morbid to PTSD. However, methodological quality of many of the studies was less than optimal. Conclusions: Trauma-focused psychological therapies are likely to be effective for combat-related PTSD but there is a need for more research to determine the efficacy of psychological treatments for other mental health disorders in veterans.

  9. Meditative Movement Therapies and Health-Related Quality-of-Life in Adults: A Systematic Review of Meta-Analyses.

    Directory of Open Access Journals (Sweden)

    George A Kelley

    Full Text Available Poor health-related quality-of-life (HRQOL is a significant public health issue while the use of meditative movement therapies has been increasing. The purpose of this investigation was to carry out a systematic review of previous meta-analyses that examined the effects of meditative movement therapies (yoga, tai chi and qigong on HRQOL in adults. Previous meta-analyses of randomized controlled trials published up through February, 2014 were included by searching nine electronic databases and cross-referencing. Dual-selection and data abstraction occurred. The Assessment of Multiple Systematic Reviews Instrument (AMSTAR was used to assess methodological quality. Standardized mean differences that were pooled using random-effects models were included. In addition, 95% prediction intervals were calculated as well as the number needed-to-treat and percentile improvements. Of the 510 citations screened, 10 meta-analyses representing a median of 3 standardized mean differences in 82 to 528 participants (median = 270 with breast cancer, schizophrenia, low back pain, heart failure and diabetes, were included. Median methodological quality was 70%. Median length, frequency and duration of the meditative movement therapies were 12 weeks, 3 times per week, for 71 minutes per session. The majority of results (78.9% favored statistically significant improvements (non-overlapping 95% confidence intervals in HRQOL, with standardized mean differences ranging from 0.18 to 2.28. More than half of the results yielded statistically significant heterogeneity (Q ≤ 0.10 and large or very large inconsistency (I2 ≥ 50%. All 95% prediction intervals included zero. The number-needed-to-treat ranged from 2 to 10 while percentile improvements ranged from 9.9 to 48.9. The results of this study suggest that meditative movement therapies may improve HRQOL in adults with selected conditions. However, a need exists for a large, more inclusive meta-analysis (PROSPERO

  10. Systematic Comparison of Brain Imaging Meta-Analyses of ToM with vPT

    Science.gov (United States)

    Schurz, Matthias; Perner, Josef

    2017-01-01

    In visual perspective taking (vPT) one has to concern oneself with what other people see and how they see it. Since seeing is a mental state, developmental studies have discussed vPT within the domain of “theory of mind (ToM)” but imaging studies have not treated it as such. Based on earlier results from several meta-analyses, we tested for the overlap of visual perspective taking studies with 6 different kinds of ToM studies: false belief, trait judgments, strategic games, social animations, mind in the eyes, and rational actions. Joint activation was observed between the vPT task and some kinds of ToM tasks in regions involving the left temporoparietal junction (TPJ), anterior precuneus, left middle occipital gyrus/extrastriate body area (EBA), and the left inferior frontal and precentral gyrus. Importantly, no overlap activation was found for the vPT tasks with the joint core of all six kinds of ToM tasks. This raises the important question of what the common denominator of all tasks that fall under the label of “theory of mind” is supposed to be if visual perspective taking is not one of them.

  11. Comparative effectiveness research: using systematic reviews and meta-analyses to synthesize empirical evidence.

    Science.gov (United States)

    Katapodi, Maria C; Northouse, Laurel L

    2011-01-01

    The increased demand for evidence-based health care practices calls for comparative effectiveness research (CER), namely the generation and synthesis of research evidence to compare the benefits and harms of alternative methods of care. A significant contribution of CER is the systematic identification and synthesis of available research studies on a specific topic. The purpose of this article is to provide an overview of methodological issues pertaining to systematic reviews and meta-analyses to be used by investigators with the purpose of conducting CER. A systematic review or meta-analysis is guided by a research protocol, which includes (a) the research question, (b) inclusion and exclusion criteria with respect to the target population and studies, (c) guidelines for obtaining relevant studies, (d) methods for data extraction and coding, (e) methods for data synthesis, and (f) guidelines for reporting results and assessing for bias. This article presents an algorithm for generating evidence-based knowledge by systematically identifying, retrieving, and synthesizing large bodies of research studies. Recommendations for evaluating the strength of evidence, interpreting findings, and discussing clinical applicability are offered.

  12. Systematic Comparison of Brain Imaging Meta-Analyses of ToM with vPT

    Directory of Open Access Journals (Sweden)

    Aditi Arora

    2017-01-01

    Full Text Available In visual perspective taking (vPT one has to concern oneself with what other people see and how they see it. Since seeing is a mental state, developmental studies have discussed vPT within the domain of “theory of mind (ToM” but imaging studies have not treated it as such. Based on earlier results from several meta-analyses, we tested for the overlap of visual perspective taking studies with 6 different kinds of ToM studies: false belief, trait judgments, strategic games, social animations, mind in the eyes, and rational actions. Joint activation was observed between the vPT task and some kinds of ToM tasks in regions involving the left temporoparietal junction (TPJ, anterior precuneus, left middle occipital gyrus/extrastriate body area (EBA, and the left inferior frontal and precentral gyrus. Importantly, no overlap activation was found for the vPT tasks with the joint core of all six kinds of ToM tasks. This raises the important question of what the common denominator of all tasks that fall under the label of “theory of mind” is supposed to be if visual perspective taking is not one of them.

  13. Systematic Comparison of Brain Imaging Meta-Analyses of ToM with vPT.

    Science.gov (United States)

    Arora, Aditi; Schurz, Matthias; Perner, Josef

    2017-01-01

    In visual perspective taking (vPT) one has to concern oneself with what other people see and how they see it. Since seeing is a mental state, developmental studies have discussed vPT within the domain of "theory of mind (ToM)" but imaging studies have not treated it as such. Based on earlier results from several meta-analyses, we tested for the overlap of visual perspective taking studies with 6 different kinds of ToM studies: false belief, trait judgments, strategic games, social animations, mind in the eyes, and rational actions. Joint activation was observed between the vPT task and some kinds of ToM tasks in regions involving the left temporoparietal junction (TPJ), anterior precuneus, left middle occipital gyrus/extrastriate body area (EBA), and the left inferior frontal and precentral gyrus. Importantly, no overlap activation was found for the vPT tasks with the joint core of all six kinds of ToM tasks. This raises the important question of what the common denominator of all tasks that fall under the label of "theory of mind" is supposed to be if visual perspective taking is not one of them.

  14. Synthesis and comparison of the meta-analyses evaluating the efficacy of memantine in moderate to severe stages of Alzheimer's disease.

    Science.gov (United States)

    Rive, Benoît; Gauthier, Serge; Costello, Sophie; Marre, Caroline; François, Clément

    2013-07-01

    The N-methyl-D-aspartate receptor antagonist, memantine, is licensed for the treatment of moderate to severe Alzheimer's disease (AD). Memantine is administered both as a monotherapy and as an add-on therapy in patients already receiving acetylcholinesterase inhibitors. Several meta-analyses have been published that examine the efficacy of memantine in the treatment of AD, based on clinical trial data. However, different disease severities and concomitant medication use in the trial populations means that synthesis of this data is challenging with numerous methodological decisions required. The main objectives of this study were to review the methodologies of different meta-analyses, assess the impact of specific methodological approaches on efficacy results, and to help interpret previous meta-analyses results concerning the efficacy of memantine in moderate to severe stages of AD. The methodologies of five meta-analyses were reviewed in terms of the included trials, combination of data, choice of outcome, and analysis methods. Results were extracted and compared in line with the methodological approach taken. The most robust results were observed on cognition, activities of daily living, and overall assessment, where memantine showed a consistent benefit over placebo. The benefit of memantine on behavioral symptoms was also demonstrated, but results were more heterogeneous. Variability could not be explained by baseline severity and concomitant treatment alone. It is stressed that interpretation of meta-analysis results must be considered within the context of the methodological approach. Overall, results from individual clinical trials and from meta-analyses demonstrate that memantine represents a valuable treatment option in AD.

  15. A systematic review of the quality of conduct and reporting of systematic reviews and meta-analyses in paediatric surgery

    Science.gov (United States)

    Gudlaugsdottir, Katrin; Andrews, James

    2017-01-01

    Objective Our objective was to evaluate quality of conduct and reporting of published systematic reviews and meta-analyses in paediatric surgery. We also aimed to identify characteristics predictive of review quality. Background Systematic reviews summarise evidence by combining sources, but are potentially prone to bias. To counter this, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was published to aid in reporting. Similarly, the Assessing the Methodological Quality of Systematic Reviews (AMSTAR) measurement tool was designed to appraise methodology. The paediatric surgical literature has seen an increasing number of reviews over the past decade, but quality has not been evaluated. Methods Adhering to PRISMA guidelines, we performed a systematic review with a priori design to identify systematic reviews and meta-analyses of interventions in paediatric surgery. From 01/2010 to 06/2016, we searched: MEDLINE, EMBASE, Cochrane, Centre for Reviews and Dissemination, Web of Science, Google Scholar, reference lists and journals. Two reviewers independently selected studies and extracted data. We assessed conduct and reporting using AMSTAR and PRISMA. Scores were calculated as the sum of reported items. We also extracted author, journal and article characteristics, and used them in exploratory analysis to determine which variables predict quality. Results 112 articles fulfilled eligibility criteria (53 systematic reviews; 59 meta-analyses). Overall, 68% AMSTAR and 56.8% PRISMA items were reported adequately. Poorest scores were identified with regards a priori design, inclusion of structured summaries, including the grey literature, citing excluded articles and evaluating bias. 13 reviews were pre-registered and 6 in PRISMA-endorsing journals. The following predicted quality in univariate analysis:, word count, Cochrane review, journal h-index, impact factor, journal endorses PRISMA, PRISMA adherence suggested in author guidance

  16. The value of urban open space: meta-analyses of contingent valuation and hedonic pricing results.

    Science.gov (United States)

    Brander, Luke M; Koetse, Mark J

    2011-10-01

    Urban open space provides a number of valuable services to urban populations, including recreational opportunities, aesthetic enjoyment, environmental functions, and may also be associated with existence values. In separate meta-analyses of the contingent valuation (CV) and hedonic pricing (HP) literature we examine which physical, socio-economic, and study characteristics determine the value of open space. The dependent variable in the CV meta-regression is defined as the value of open space per hectare per year in 2003 US$, and in the HP model as the percentage change in house price for a 10 m decrease in distance to open space. Using a multi-level modelling approach we find in both the CV and HP analyses that there is a positive and significant relationship between the value of urban open space and population density, indicating that scarcity and crowdedness matter, and that the value of open space does not vary significantly with income. Further, urban parks are more highly valued than other types of urban open space (forests, agricultural and undeveloped land) and methodological differences in study design have a large influence on estimated values from both CV and HP. We also find important regional differences in preferences for urban open space, which suggests that the potential for transferring estimated values between regions is likely to be limited. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Weighing Evidence “Steampunk” Style via the Meta-Analyser

    Science.gov (United States)

    Bowden, Jack; Jackson, Chris

    2016-01-01

    ABSTRACT The funnel plot is a graphical visualization of summary data estimates from a meta-analysis, and is a useful tool for detecting departures from the standard modeling assumptions. Although perhaps not widely appreciated, a simple extension of the funnel plot can help to facilitate an intuitive interpretation of the mathematics underlying a meta-analysis at a more fundamental level, by equating it to determining the center of mass of a physical system. We used this analogy to explain the concepts of weighing evidence and of biased evidence to a young audience at the Cambridge Science Festival, without recourse to precise definitions or statistical formulas and with a little help from Sherlock Holmes! Following on from the science fair, we have developed an interactive web-application (named the Meta-Analyser) to bring these ideas to a wider audience. We envisage that our application will be a useful tool for researchers when interpreting their data. First, to facilitate a simple understanding of fixed and random effects modeling approaches; second, to assess the importance of outliers; and third, to show the impact of adjusting for small study bias. This final aim is realized by introducing a novel graphical interpretation of the well-known method of Egger regression. PMID:28003684

  18. Association of HLA-DQA1 and -DQB1 alleles with type I diabetes in Arabs: a meta-analyses.

    Science.gov (United States)

    Hamzeh, A R; Nair, P; Al-Khaja, N; Al Ali, M T

    2015-07-01

    This study aimed at assessing the nature and significance of associations between various alleles of HLA-DQA1, HLA-DQB1, and type I diabetes (T1D) in Arab populations. Evidence from literature (published before 20 April 2015) was amassed and analysed through multiple meta-analyses, which yielded effect summary odds ratios and 95% confidence intervals for 24 alleles and 4 haplotypes. A total of 1273 cases and 1747 controls from 16 studies were analysed. High levels of significance were obtained to support higher T1D risk when harbouring DQA1*03:01. The alleles DQB1*02:01 and *03:02 and the haplotypes DR3 and DR4 were significant risk factors, albeit with high publication heterogeneity. The protective effects of DQA1*01:01, DQB1*05:03, *06:02, *06:03, and *06:04 were robustly suggested by all indicators of meta-analyses. The haplotypes DR7 and DR11 were strongly suggested to be protective in Arabs. A relatively small number of studies have emerged from Arab countries, mostly with inadequate power on an individual basis. This study fills the gap by providing significant size effect of human leukocyte antigen (HLA) alleles and completes the continuum of global ethnic differences in this context.

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

    Science.gov (United States)

    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.

  20. Conceptualizing neuropsychiatric diseases with multimodal data-driven meta-analyses – The case of behavioral variant frontotemporal dementia

    Science.gov (United States)

    Schroeter, Matthias L.; Laird, Angela R.; Chwiesko, Caroline; Deuschl, Christine; Schneider, Else; Bzdok, Danilo; Eickhoff, Simon B.; Neumann, Jane

    2014-01-01

    Introduction Uniform coordinate systems in neuroimaging research have enabled comprehensive systematic and quantitative meta-analyses. Such approaches are particularly relevant for neuropsychiatric diseases, the understanding of their symptoms, prediction and treatment. Behavioral variant frontotemporal dementia (bvFTD), a common neurodegenerative syndrome, is characterized by deep alterations in behavior and personality. Investigating this ‘nexopathy’ elucidates the healthy social and emotional brain. Methods Here, we combine three multimodal meta-analyses approaches – anatomical & activation likelihood estimates and behavioral domain profiles – to identify neural correlates of bvFTD in 417 patients and 406 control subjects and to extract mental functions associated with this disease by meta-analyzing functional activation studies in the comprehensive probabilistic functional brain atlas of the BrainMap database. Results The analyses identify the frontomedian cortex, basal ganglia, anterior insulae and thalamus as most relevant hubs, with a regional dissociation between atrophy and hypometabolism. Neural networks affected by bvFTD were associated with emotion and reward processing, empathy and executive functions (mainly inhibition), suggesting these functions as core domains affected by the disease and finally leading to its clinical symptoms. In contrast, changes in theory of mind or mentalizing abilities seem to be secondary phenomena of executive dysfunctions. Conclusions The study creates a novel conceptual framework to understand neuropsychiatric diseases by powerful data-driven meta-analytic approaches that shall be extended to the whole neuropsychiatric spectrum in the future. PMID:24763126

  1. Two Meta-Analyses Exploring the Relationship between Teacher Clarity and Student Learning

    Science.gov (United States)

    Titsworth, Scott; Mazer, Joseph P.; Goodboy, Alan K.; Bolkan, San; Myers, Scott A.

    2015-01-01

    This article reports the findings of two meta-analyses that explored the relationship between teacher clarity and student learning. Combined, the results suggest that teacher clarity has a larger effect for student affective learning than for cognitive learning. However, neither the effects for cognitive learning nor affective learning were…

  2. Meta-Analyses of Human Cell-Based Cardiac Regeneration Therapies

    DEFF Research Database (Denmark)

    Gyöngyösi, Mariann; Wojakowski, Wojciech; Navarese, Eliano P;

    2016-01-01

    In contrast to multiple publication-based meta-analyses involving clinical cardiac regeneration therapy in patients with recent myocardial infarction, a recently published meta-analysis based on individual patient data reported no effect of cell therapy on left ventricular function or clinical ou...

  3. Network meta-analyses performed by contracting companies and commissioned by industry

    NARCIS (Netherlands)

    Schuit, Ewoud; Ioannidis, John P A

    2016-01-01

    Background: Industry commissions contracting companies to perform network meta-analysis for health technology assessment (HTA) and reimbursement submissions. Our objective was to estimate the number of network meta-analyses performed by consulting companies contracted by industry, to assess whether

  4. Preventive intervention possibilities in radiotherapy- and chemotherapy-induced oral mucositis : Results of meta-analyses

    NARCIS (Netherlands)

    Stokman, M A; Spijkervet, F K L; Boezen, H M; Schouten, J.P.; Roodenburg, J L N; de Vries, E G E

    2006-01-01

    The aim of these meta-analyses was to evaluate the effectiveness of interventions for the prevention of oral mucositis in cancer patients treated with head and neck radiotherapy and/or chemotherapy, with a focus on randomized clinical trials. A literature search was performed for reports of randomiz

  5. Stuttering, induced fluency, and natural fluency: a hierarchical series of activation likelihood estimation meta-analyses.

    Science.gov (United States)

    Budde, Kristin S; Barron, Daniel S; Fox, Peter T

    2014-12-01

    Developmental stuttering is a speech disorder most likely due to a heritable form of developmental dysmyelination impairing the function of the speech-motor system. Speech-induced brain-activation patterns in persons who stutter (PWS) are anomalous in various ways; the consistency of these aberrant patterns is a matter of ongoing debate. Here, we present a hierarchical series of coordinate-based meta-analyses addressing this issue. Two tiers of meta-analyses were performed on a 17-paper dataset (202 PWS; 167 fluent controls). Four large-scale (top-tier) meta-analyses were performed, two for each subject group (PWS and controls). These analyses robustly confirmed the regional effects previously postulated as "neural signatures of stuttering" (Brown, Ingham, Ingham, Laird, & Fox, 2005) and extended this designation to additional regions. Two smaller-scale (lower-tier) meta-analyses refined the interpretation of the large-scale analyses: (1) a between-group contrast targeting differences between PWS and controls (stuttering trait); and (2) a within-group contrast (PWS only) of stuttering with induced fluency (stuttering state).

  6. Genome-wide meta-analyses identify multiple loci associated with smoking behavior

    NARCIS (Netherlands)

    H. Furberg (Helena); Y. Kim (Yunjung); J. Dackor (Jennifer); E.A. Boerwinkle (Eric); N. Franceschini (Nora); D. Ardissino (Diego); L. Bernardinelli (Luisa); P.M. Mannucci (Pier); F. Mauri (Francesco); P.A. Merlini (Piera); D. Absher (Devin); T.L. Assimes (Themistocles); S.P. Fortmann (Stephen); C. Iribarren (Carlos); J.W. Knowles (Joshua); T. Quertermous (Thomas); L. Ferrucci (Luigi); T. Tanaka (Toshiko); J.C. Bis (Joshua); T. Haritunians (Talin); B. McKnight (Barbara); B.M. Psaty (Bruce); K.D. Taylor (Kent); E.L. Thacker (Evan); P. Almgren (Peter); L. Groop (Leif); C. Ladenvall (Claes); M. Boehnke (Michael); A.U. Jackson (Anne); K.L. Mohlke (Karen); H.M. Stringham (Heather); J. Tuomilehto (Jaakko); E.J. Benjamin (Emelia); S.J. Hwang; D. Levy (Daniel); S.R. Preis; R.S. Vasan (Ramachandran Srini); J. Duan (Jubao); P.V. Gejman (Pablo); D.F. Levinson (Douglas); A.R. Sanders (Alan); J. Shi (Jianxin); E.H. Lips (Esther); J.D. McKay (James); A. Agudo (Antonio); L. Barzan (Luigi); V. Bencko (Vladimir); S. Benhamou (Simone); X. Castellsagué (Xavier); C. Canova (Cristina); D.I. Conway (David); E. Fabianova (Eleonora); L. Foretova (Lenka); V. Janout (Vladimir); C.M. Healy (Claire); I. Holcátová (Ivana); K. Kjaerheim (Kristina); P. Lagiou; J. Lissowska (Jolanta); R. Lowry (Ray); T.V. MacFarlane (Tatiana); D. Mates (Dana); L. Richiardi (Lorenzo); P. Rudnai (Peter); N. Szeszenia-Dabrowska (Neonilia); D. Zaridze; A. Znaor (Ariana); M. Lathrop (Mark); P. Brennan (Paul); S. Bandinelli (Stefania); T.M. Frayling (Timothy); J.M. Guralnik (Jack); Y. Milaneschi (Yuri); J.R.B. Perry (John); D. Altshuler (David); R. Elosua (Roberto); S. Kathiresan (Sekar); G. Lucas (Gavin); O. Melander (Olle); V. Salomaa (Veikko); S.M. Schwartz (Stephen); B.F. Voight (Benjamin); B.W.J.H. Penninx (Brenda); J.H. Smit (Johannes); N. Vogelzangs (Nicole); D.I. Boomsma (Dorret); E.J.C. de Geus (Eco); J.M. Vink (Jacqueline); G.A.H.M. Willemsen (Gonneke); S.J. Chanock (Stephen); F. Gu (Fangyi); S.E. Hankinson (Susan); D. Hunter (David); A. Hofman (Albert); H.W. Tiemeier (Henning); A.G. Uitterlinden (André); P. Tikka-Kleemola (Päivi); S. Walter (Stefan); D.I. Chasman (Daniel); B.M. Everett (Brendan); G. Pare (Guillaume); P.M. Ridker (Paul); M.D. Li (Ming); H.H. Maes (Hermine); J. Audrain-Mcgovern (Janet); D. Posthuma (Danielle); L.M. Thornton (Laura); C. Lerman (Caryn); J. Kaprio (Jaakko); J.E. Rose (Jed); J.P.A. Ioannidis (John); P. Kraft (Peter); D.Y. Lin (Dan); P.F. Sullivan (Patrick); C.J. O'Donnell (Christopher)

    2010-01-01

    textabstractConsistent but indirect evidence has implicated genetic factors in smoking behavior. We report meta-analyses of several smoking phenotypes within cohorts of the Tobacco and Genetics Consortium (n = 74,053). We also partnered with the European Network of Genetic and Genomic Epidemiology (

  7. The Validity of Individual Rorschach Variables: Systematic Reviews and Meta-Analyses of the Comprehensive System

    Science.gov (United States)

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

    2013-01-01

    We systematically evaluated the peer-reviewed Rorschach validity literature for the 65 main variables in the popular Comprehensive System (CS). Across 53 meta-analyses examining variables against externally assessed criteria (e.g., observer ratings, psychiatric diagnosis), the mean validity was r = 0.27 (k = 770) as compared to r = 0.08 (k = 386)…

  8. Network meta-analyses performed by contracting companies and commissioned by industry

    NARCIS (Netherlands)

    Schuit, Ewoud; Ioannidis, John P A

    2016-01-01

    Background: Industry commissions contracting companies to perform network meta-analysis for health technology assessment (HTA) and reimbursement submissions. Our objective was to estimate the number of network meta-analyses performed by consulting companies contracted by industry, to assess whether

  9. Internet-Delivered Health Interventions That Work: Systematic Review of Meta-Analyses and Evaluation of Website Availability.

    Science.gov (United States)

    Rogers, Mary Am; Lemmen, Kelsey; Kramer, Rachel; Mann, Jason; Chopra, Vineet

    2017-03-24

    Due to easy access and low cost, Internet-delivered therapies offer an attractive alternative to improving health. Although numerous websites contain health-related information, finding evidence-based programs (as demonstrated through randomized controlled trials, RCTs) can be challenging. We sought to bridge the divide between the knowledge gained from RCTs and communication of the results by conducting a global systematic review and analyzing the availability of evidence-based Internet health programs. The study aimed to (1) discover the range of health-related topics that are addressed through Internet-delivered interventions, (2) generate a list of current websites used in the trials which demonstrate a health benefit, and (3) identify gaps in the research that may have hindered dissemination. Our focus was on Internet-delivered self-guided health interventions that did not require real-time clinical support. A systematic review of meta-analyses was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO Registration Number CRD42016041258). MEDLINE via Ovid, PsycINFO, Embase, Cochrane Database of Systematic Reviews, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched. Inclusion criteria included (1) meta-analyses of RCTs, (2) at least one Internet-delivered intervention that measured a health-related outcome, and (3) use of at least one self-guided intervention. We excluded group-based therapies. There were no language restrictions. Of the 363 records identified through the search, 71 meta-analyses met inclusion criteria. Within the 71 meta-analyses, there were 1733 studies that contained 268 unique RCTs which tested self-help interventions. On review of the 268 studies, 21.3% (57/268) had functional websites. These included evidence-based Web programs on substance abuse (alcohol, tobacco, cannabis), mental health (depression, anxiety, post-traumatic stress disorder

  10. Understanding and evaluating systematic reviews and meta-analyses

    Directory of Open Access Journals (Sweden)

    Michael Bigby

    2014-01-01

    Full Text Available A systematic review is a summary of existing evidence that answers a specific clinical question, contains a thorough, unbiased search of the relevant literature, explicit criteria for assessing studies and structured presentation of the results. A systematic review that incorporates quantitative pooling of similar studies to produce an overall summary of treatment effects is a meta-analysis. A systematic review should have clear, focused clinical objectives containing four elements expressed through the acronym PICO ( Patient, group of patients, or problem, an Intervention, a Comparison intervention and specific O utcomes. Explicit and thorough search of the literature is a pre-requisite of any good systematic review. Reviews should have pre-defined explicit criteria for what studies would be included and the analysis should include only those studies that fit the inclusion criteria. The quality (risk of bias of the primary studies should be critically appraised. Particularly the role of publication and language bias should be acknowledged and addressed by the review, whenever possible. Structured reporting of the results with quantitative pooling of the data must be attempted, whenever appropriate. The review should include interpretation of the data, including implications for clinical practice and further research. Overall, the current quality of reporting of systematic reviews remains highly variable.

  11. A literature review and meta-analyses of cannabis use and suicidality.

    Science.gov (United States)

    Borges, Guilherme; Bagge, Courtney L; Orozco, Ricardo

    2016-05-01

    We lack a review of the epidemiological literature on cannabis use (acute use and chronic-usual quantity/frequency and heavy use) and suicidality (suicide death, suicide ideation, suicide attempt). The English language literature on Medline, PsychInfo, Google Scholar, and public-use databases was searched for original articles, critical review reports, and public use data on cannabis use and suicide for the period ranging from 1990-2015 (February). Odds ratios (OR) from random effects in meta-analyses for any cannabis use and heavy cannabis use were calculated. The acute cannabis-suicidality literature mostly includes descriptive toxicology reports. In terms of death by suicide, the average positive cannabis rate was 9.50% for studies sampling from all suicides, with higher cannabis detection rates amongst suicide decedents by non-overdose methods. We found only 4 studies providing estimates for any chronic cannabis use and death by suicide (OR=2.56 (1.25-5.27)). After deleting duplicates we found 6 studies on any cannabis use and suicide ideation (OR=1.43 (1.13-1.83)), 5 studies on heavy cannabis use and suicide ideation (OR=2.53 (1.00-6.39)), 6 studies on any cannabis use and suicide attempt (OR=2.23 (1.24-4.00)) and 6 studies on heavy cannabis use and suicide attempt (OR=3.20 (1.72-5.94)). We currently lack evidence that acute cannabis use increases imminent risk for suicidality. The evidence tends to support that chronic cannabis use can predict suicidality, but the lack of homogeneity in the measurement of cannabis exposure and, in some instances, the lack of systematic control for known risk factors tempered this finding. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Recommendations for individual participant data meta-analyses on work stressors and health outcomes: comments on IPD-Work Consortium papers.

    Science.gov (United States)

    Choi, Bong Kyoo; Schnall, Peter; Landsbergis, Paul; Dobson, Marnie; Ko, Sangbaek; Gómez-Ortiz, Viviola; Juárez-Garcia, Arturo; Baker, Dean

    2015-05-01

    The IPD-Work (individual-participant data meta-analysis of working populations) Consortium has published several papers on job strain (the combination of low job control and high job demands) based on Karasek's demand-control model (1) and health-related outcomes including cardiovascular disease (CVD), cancer, obesity, diabetes as well as health-related behaviors, utilizing meta-analyses of a pooled database of study participants from 17 European cohorts. An IPD approach has some advantages over typical meta-analyses, eg, having access to all the data for each individual allows for additional analyses, compared to typical meta-analyses. However, such an approach, like other meta-analyses, is not free from errors and biases (2-6) when it is not conducted appropriately. In our review of the IPD-Work Consortium's (hereafter called the Consortium) publications of the last two years, we have identified and pointed out several conceptual and methodological errors, as well as unsubstantiated conclusions and inappropriate recommendations for worksite public health policies (6-15). However, the Consortium has not yet appropriately addressed many of the issues we have raised. Also several major errors and biases underlying the Consortium IPD meta-analysis publications have not been presented in a comprehensive way, nor have they been discussed widely among work stress researchers. We are concerned that the same errors and biases could be repeated in future IPD Consortium meta-analysis publications as well as by other researchers who are interested in meta-analyses on work stressors and health outcomes. It is possible that the inappropriate interpretations in the Consortium publications, which remained uncorrected to date, may have a negative impact on the international efforts of the work stress research community to improve the health of working populations. Recently, Dr. Töres Theorell, a principal investigator of the Consortium, responded in this journal (16) to some of

  13. [Clinical research XXIII. From clinical judgment to meta-analyses].

    Science.gov (United States)

    Rivas-Ruiz, Rodolfo; Castelán-Martínez, Osvaldo D; Pérez-Rodríguez, Marcela; Palacios-Cruz, Lino; Noyola-Castillo, Maura E; Talavera, Juan O

    2014-01-01

    Systematic reviews (SR) are studies made in order to ask clinical questions based on original articles. Meta-analysis (MTA) is the mathematical analysis of SR. These analyses are divided in two groups, those which evaluate the measured results of quantitative variables (for example, the body mass index -BMI-) and those which evaluate qualitative variables (for example, if a patient is alive or dead, or if he is healing or not). Quantitative variables generally use the mean difference analysis and qualitative variables can be performed using several calculations: odds ratio (OR), relative risk (RR), absolute risk reduction (ARR) and hazard ratio (HR). These analyses are represented through forest plots which allow the evaluation of each individual study, as well as the heterogeneity between studies and the overall effect of the intervention. These analyses are mainly based on Student's t test and chi-squared. To take appropriate decisions based on the MTA, it is important to understand the characteristics of statistical methods in order to avoid misinterpretations.

  14. Overview of Meta-Analyses on Early Intensive Behavioral Intervention for Young Children with Autism Spectrum Disorders

    Science.gov (United States)

    Reichow, Brian

    2012-01-01

    This paper presents an overview of 5 meta-analyses of early intensive behavioral intervention (EIBI) for young children with autism spectrum disorders (ASDs) published in 2009 and 2010. There were many differences between meta-analyses, leading to different estimates of effect and overall conclusions. The weighted mean effect sizes across…

  15. Reporting Quality of Systematic Reviews and Meta-Analyses of Otorhinolaryngologic Articles Based on the PRISMA Statement

    NARCIS (Netherlands)

    Peters, Jeroen P M; Hooft, Lotty; Grolman, Wilko; Stegeman, Inge

    2015-01-01

    BACKGROUND: Systematic reviews (SRs) and meta-analyses (MAs) provide the highest possible level of evidence. However, poor conduct or reporting of SRs and MAs may reduce their utility. The PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analyses) was developed to help

  16. Reporting Quality of Systematic Reviews and Meta-Analyses of Otorhinolaryngologic Articles Based on the PRISMA Statement

    NARCIS (Netherlands)

    Peters, Jeroen P M; Hooft, Lotty; Grolman, Wilko; Stegeman, Inge

    2015-01-01

    BACKGROUND: Systematic reviews (SRs) and meta-analyses (MAs) provide the highest possible level of evidence. However, poor conduct or reporting of SRs and MAs may reduce their utility. The PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analyses) was developed to help aut

  17. Reporting Quality of Systematic Reviews and Meta-Analyses of Otorhinolaryngologic Articles Based on the PRISMA Statement

    NARCIS (Netherlands)

    Peters, Jeroen P M; Hooft, Lotty; Grolman, Wilko; Stegeman, Inge

    2015-01-01

    BACKGROUND: Systematic reviews (SRs) and meta-analyses (MAs) provide the highest possible level of evidence. However, poor conduct or reporting of SRs and MAs may reduce their utility. The PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analyses) was developed to help aut

  18. Non-independence and sensitivity analyses in ecological and evolutionary meta-analyses.

    Science.gov (United States)

    Noble, Daniel W A; Lagisz, Malgorzata; O'dea, Rose E; Nakagawa, Shinichi

    2017-01-30

    Meta-analysis is an important tool for synthesizing research on a variety of topics in ecology and evolution, including molecular ecology, but can be susceptible to non-independence. Non-independence can affect two major interrelated components of a meta-analysis: 1) the calculation of effect size statistics and 2) the estimation of overall meta-analytic estimates and their uncertainty. While some solutions to non-independence exist at the statistical analysis stages, there is little advice on what to do when complex analyses are not possible, or when studies with non-independent experimental designs exist in the data. Here we argue that exploring the effects of procedural decisions in a meta-analysis (e.g., inclusion of different quality data, choice of effect size) and statistical assumptions (e.g., assuming no phylogenetic covariance) using sensitivity analyses are extremely important in assessing the impact of non-independence. Sensitivity analyses can provide greater confidence in results and highlight important limitations of empirical work (e.g., impact of study design on overall effects). Despite their importance, sensitivity analyses are seldom applied to problems of non-independence. To encourage better practice for dealing with non-independence in meta-analytic studies, we present accessible examples demonstrating the impact that ignoring non-independence can have on meta-analytic estimates. We also provide pragmatic solutions for dealing with non-independent study designs, and for analyzing dependent effect sizes. Additionally, we offer reporting guidelines that will facilitate disclosure of the sources of non-independence in meta-analyses, leading to greater transparency and more robust conclusions. This article is protected by copyright. All rights reserved.

  19. ANIMA: A data-sharing initiative for neuroimaging meta-analyses.

    Science.gov (United States)

    Reid, Andrew T; Bzdok, Danilo; Genon, Sarah; Langner, Robert; Müller, Veronika I; Eickhoff, Claudia R; Hoffstaedter, Felix; Cieslik, Edna-Clarisse; Fox, Peter T; Laird, Angela R; Amunts, Katrin; Caspers, Svenja; Eickhoff, Simon B

    2016-01-01

    Meta-analytic techniques allow cognitive neuroscientists to pool large amounts of data across many individual task-based functional neuroimaging experiments. These methods have been aided by the introduction of online databases such as Brainmap.org or Neurosynth.org, which collate peak activation coordinates obtained from thousands of published studies. Findings from meta-analytic studies typically include brain regions which are consistently activated across studies for specific contrasts, investigating cognitive or clinical hypotheses. These regions can be subsequently used as the basis for seed-based connectivity analysis, or formally compared to neuroimaging data in order to help interpret new findings. To facilitate such approaches, we have developed a new online repository of meta-analytic neuroimaging results, named the Archive of Neuroimaging Meta-analyses (ANIMA). The ANIMA platform consists of an intuitive online interface for querying, downloading, and contributing data from published meta-analytic studies. Additionally, to aid the process of organizing, visualizing, and working with these data, we present an open-source desktop application called Volume Viewer. Volume Viewer allows users to easily arrange imaging data into composite stacks, and save these sessions as individual files, which can also be uploaded to the ANIMA database. The application also allows users to perform basic functions, such as computing conjunctions between images, or extracting regions-of-interest or peak coordinates for further analysis. The introduction of this new resource will enhance the ability of researchers to both share their findings and incorporate existing meta-analytic results into their own research.

  20. Incorporating alternative design clinical trials in network meta-analyses

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    Thorlund K

    2014-12-01

    response were incomplete, as all induction nonresponders were assigned to golimumab 100 mg. Data from the PURSUIT trial were combined with ACT-1 and ULTRA-2 trial data to impute missing information. Discussion: We have demonstrated methods for converting results from alternative study designs to more conventional parallel randomized clinical trials. These conversions allow for indirect treatment comparisons that are informed by a wider array of evidence, adding to the precision of estimates. Keywords: adaptive, network meta-analysis, indirect treatment comparison, ulcerative colitis, golimumab

  1. The assessment of the quality of reporting of meta-analyses in diagnostic research: a systematic review

    Science.gov (United States)

    2011-01-01

    Background Over the last decade there have been a number of guidelines published, aimed at improving the quality of reporting in published studies and reviews. In systematic reviews this may be measured by their compliance with the PRISMA statement. This review aims to evaluate the quality of reporting in published meta-analyses of diagnostic tests, using the PRISMA statement and establish whether there has been a measurable improvement over time. Methods Eight databases were searched for reviews published prior to 31st December 2008. Studies were selected if they evaluated a diagnostic test, measured performance, searched two or more databases, stated the search terms and inclusion criteria, and used a statistical method to summarise a test's performance. Data were extracted on the review characteristics and items of the PRISMA statement. To measure the change in the quality of reporting over time, PRISMA items for two periods of equal duration were compared. Results Compliance with the PRISMA statement was generally poor: none of the reviews completely adhered to all 27 checklist items. Of the 236 meta-analyses included following selection: only 2(1%) reported the study protocol; 59(25%) reported the searches used; 76(32%) reported the results of a risk of bias assessment; and 82(35%) reported the abstract as a structured summary. Only 11 studies were published before 2000. Thus, the impact of QUOROM on the quality of reporting was not evaluated. However, the periods 2001-2004 and 2005-2008 (covering 93% of studies) were compared using relative risks (RR). There was an increase in the proportion of reviews reporting on five PRISMA items: eligibility criteria (RR 1.13, 95% CI 1.00 - 1.27); risk of bias across studies (methods) (RR 1.81, 95% CI 1.34 - 2.44); study selection results (RR 1.48, 95% CI 1.05 - 2.09); results of individual studies (RR 1.37, 95% CI 1.09 - 1.72); risk of bias across studies (results) (RR 1.65, 95% CI 1.20 - 2.25). Conclusion Although there

  2. The epidemiology of hepatitis C virus in the Maghreb region: systematic review and meta-analyses.

    Directory of Open Access Journals (Sweden)

    Fatima A Fadlalla

    Full Text Available To systematically review and synthesize available epidemiological data on hepatitis C virus (HCV prevalence and incidence in the Maghreb region and to estimate the country-specific population-level HCV prevalence.We conducted a systematic review of HCV antibody prevalence and incidence in the Maghreb countries as outlined by the PRISMA guidelines. Meta-analyses were conducted using DerSimonian-Laird random-effect models with inverse variance weighting to pool HCV prevalence estimates among general population groups.We identified 133 HCV prevalence measures and two HCV incidence measures. Among high risk groups, HCV prevalence ranged between 22% and 94% among people who inject drugs, 20% and 76% among dialysis patients, and 2% and 51% among hemophiliacs. Among intermediate-risk groups, considerable but widely variable HCV prevalence was found. Most common risk factors cited across studies were the duration of dialysis, number of transfusions, and having a history of surgery or dental work. The national HCV prevalence in Algeria was estimated at 0.3% (95%CI: 0.1-0.5, Libya 1.2% (95%CI: 1.1-1.3, Mauritania 1.1% (95%CI: 0-2.3, Morocco 0.8% (95%CI: 0.5-1.2, and Tunisia 0.6% (95%CI: 0.5-0.8.HCV prevalence in the Maghreb region of the Middle East and North Africa is comparable to that in developed countries of about 1%. HCV exposures appear often to be linked to medical care and are suggestive of ongoing transmission in such settings. Injecting drug use appears also to be a major, though not dominant, contributor to HCV transmission. Further research is needed to draw a more thorough understanding of HCV epidemiology, especially in the countries with limited number of studies. HCV prevention policy and programming in these countries should focus on the settings of exposure.

  3. Reporting characteristics of meta-analyses in orthodontics: methodological assessment and statistical recommendations.

    Science.gov (United States)

    Papageorgiou, Spyridon N; Papadopoulos, Moschos A; Athanasiou, Athanasios E

    2014-02-01

    Ideally meta-analyses (MAs) should consolidate the characteristics of orthodontic research in order to produce an evidence-based answer. However severe flaws are frequently observed in most of them. The aim of this study was to evaluate the statistical methods, the methodology, and the quality characteristics of orthodontic MAs and to assess their reporting quality during the last years. Electronic databases were searched for MAs (with or without a proper systematic review) in the field of orthodontics, indexed up to 2011. The AMSTAR tool was used for quality assessment of the included articles. Data were analyzed with Student's t-test, one-way ANOVA, and generalized linear modelling. Risk ratios with 95% confidence intervals were calculated to represent changes during the years in reporting of key items associated with quality. A total of 80 MAs with 1086 primary studies were included in this evaluation. Using the AMSTAR tool, 25 (27.3%) of the MAs were found to be of low quality, 37 (46.3%) of medium quality, and 18 (22.5%) of high quality. Specific characteristics like explicit protocol definition, extensive searches, and quality assessment of included trials were associated with a higher AMSTAR score. Model selection and dealing with heterogeneity or publication bias were often problematic in the identified reviews. The number of published orthodontic MAs is constantly increasing, while their overall quality is considered to range from low to medium. Although the number of MAs of medium and high level seems lately to rise, several other aspects need improvement to increase their overall quality.

  4. Cognitive dysfunction in bipolar disorder and schizophrenia: a systematic review of meta-analyses

    Directory of Open Access Journals (Sweden)

    Bortolato B

    2015-12-01

    Full Text Available Beatrice Bortolato,1 Kamilla W Miskowiak,2 Cristiano A Köhler,3 Eduard Vieta,4 André F Carvalho3 1Department of Mental Health, ULSS 10 “Veneto Orientale”, Venice, Italy; 2Psychiatric Centre Copenhagen, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark; 3Translational Psychiatry Research Group and Department of Clinical Medicine, Faculty of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil; 4Bipolar Disorders Program, Institute of Neuroscience, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Catalonia, Spain Abstract: Cognitive impairment is a core feature of schizophrenia (SZ and bipolar disorder (BD. A neurocognitive profile characterized by widespread cognitive deficits across multiple domains in the context of substantial intellectual impairment, which appears to antedate illness onset, is a replicated finding in SZ. There is no specific neuropsychological signature that can facilitate the diagnostic differentiation of SZ and BD, notwithstanding, neuropsychological deficits appear more severe in SZ. The literature in this field has provided contradictory results due to methodological differences across studies. Meta-analytic techniques may offer an opportunity to synthesize findings and to control for potential sources of heterogeneity. Here, we performed a systematic review of meta-analyses of neuropsychological findings in SZ and BD. While there is no conclusive evidence for progressive cognitive deterioration in either SZ or BD, some findings point to more severe cognitive deficits in patients with early illness onset across both disorders. A compromised pattern of cognitive functioning in individuals at familiar and/or clinical risk to psychosis as well as in first-degree relatives of BD patients suggests that early neurodevelopmental factors may play a role in the emergence of cognitive deficits in both disorders. Premorbid intellectual impairment in SZ and at least in a

  5. Targeting intensive versus conventional glycaemic control for type 1 diabetes mellitus: a systematic review with meta-analyses and trial sequential analyses of randomised clinical trials

    OpenAIRE

    Kähler, Pernille; Grevstad, Berit; Almdal, Thomas; Gluud, Christian; Wetterslev, Jørn; Vaag, Allan; Hemmingsen, Bianca

    2014-01-01

    Objective To assess the benefits and harms of targeting intensive versus conventional glycaemic control in patients with type 1 diabetes mellitus. Design A systematic review with meta-analyses and trial sequential analyses of randomised clinical trials. Data sources The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded and LILACS to January 2013. Study selection Randomised clinical trials that prespecified different targets of glycaemic control in participants at any age with...

  6. Meat consumption and cancer risk: a critical review of published meta-analyses.

    Science.gov (United States)

    Lippi, Giuseppe; Mattiuzzi, Camilla; Cervellin, Gianfranco

    2016-01-01

    Dietary habits play a substantial role for increasing or reducing cancer risk. We performed a critical review of scientific literature, to describe the findings of meta-analyses that explored the association between meat consumption and cancer risk. Overall, 42 eligible meta-analyses were included in this review, in which meat consumption was assumed from sheer statistics. Convincing association was found between larger intake of red meat and cancer, especially with colorectal, lung, esophageal and gastric malignancies. Increased consumption of processed meat was also found to be associated with colorectal, esophageal, gastric and bladder cancers. Enhanced intake of white meat or poultry was found to be negatively associated with some types of cancers. Larger beef consumption was significantly associated with cancer, whereas the risk was not increased consuming high amounts of pork. Our analysis suggest increased risk of cancer in subjects consuming large amounts of red and processed meat, but not in those with high intake of white meat or poultry.

  7. Deconstructing evidence in orthodontics: making sense of systematic reviews, randomized clinical trials, and meta-analyses.

    Science.gov (United States)

    Rinchuse, Donald J; Rinchuse, Daniel J; Kandasamy, Sanjivan; Ackerman, Marc B

    2008-01-01

    Much has been written in support of systematic reviews and the randomized clinical trials and meta-analyses upon which they are based. Clearly, the medical profession (as opposed to the dental profession) has been the leader in publishing the benefits of systematic reviews over the traditional, qualitative narrative reviews. At the same time, the medical profession also appears to be ahead of the dental profession in recognizing the limitations of such reviews. That said, there are a number of inherent problems with systematic reviews, as well as the randomized clinical trials and meta-analyses that back them up. To better facilitate evidence-based decision making, this article discusses the shortcomings of systematic reviews so that practitioners are fully aware of their drawbacks, as well as their benefits.

  8. Physical activity on prescription schemes (PARS): do programme characteristics influence effectiveness? Results of a systematic review and meta-analyses

    Science.gov (United States)

    Arsenijevic, Jelena; Groot, Wim

    2017-01-01

    Background Physical activity on prescription schemes (PARS) are health promotion programmes that have been implemented in various countries. The aim of this study was to outline the differences in the design of PARS in different countries. This study also explored the differences in the adherence rate to PARS and the self-reported level of physical activity between PARS users in different countries. Method A systematic literature review and meta-analyses were conducted. We searched PubMed and EBASCO in July 2015 and updated our search in September 2015. Studies that reported adherence to the programme and self-reported level of physical activity, published in the English language in a peer-reviewed journal since 2000, were included. The difference in the pooled adherence rate after finishing the PARS programme and the adherence rate before or during the PARS programme was 17% (95% CI 9% to 24%). The difference in the pooled physical activity was 0.93 unit score (95 CI −3.57 to 1.71). For the adherence rate, a meta-regression was conducted. Results In total, 37 studies conducted in 11 different countries met the inclusion criteria. Among them, 31 reported the adherence rate, while the level of physical activity was reported in 17 studies. Results from meta-analyses show that PARS had an effect on the adherence rate of physical activity, while the results from the meta-regressions show that programme characteristics such as type of chronic disease and the follow-up period influenced the adherence rate. Conclusions The effects of PARS on adherence and self-reported physical activity were influenced by programme characteristics and also by the design of the study. Future studies on the effectiveness of PARS should use a prospective longitudinal design and combine quantitative and qualitative data. Furthermore, future evaluation studies should distinguish between evaluating the adherence rate and the self-reported physical activity among participants with different

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

    Science.gov (United States)

    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.

  10. Comments on Meta-Analyses in General and in Stem Cell Research: An Overview and Cautionary Advice.

    Science.gov (United States)

    Thomas, Ronald L; Parker, Graham C

    2015-09-15

    Meta-analysis, a tool for contrasting and combining results from different research studies, has been around now for over 40 years. Journal editors are eager to publish the results from meta-analyses, as they propose to represent the integration of best research evidence with clinical expertise and patient values. There are guidelines available, most notably through the Cochrane Collaborative, for investigators to follow in conducting a responsible and, therefore publishable, meta-analysis. Despite the burgeoning popularity of this powerful analytical tool, the procedure is not without its pitfalls. In this study, we advise the readership to familiarize themselves with the most common shortcomings in an effort to help elevate our ability to critically appraise the results of these analyses.

  11. The Efficacy of Noble Gases in the Attenuation of Ischemia Reperfusion Injury: A Systematic Review and Meta-Analyses.

    Science.gov (United States)

    De Deken, Julie; Rex, Steffen; Monbaliu, Diethard; Pirenne, Jacques; Jochmans, Ina

    2016-09-01

    Noble gases have been attributed to organ protective effects in ischemia reperfusion injury in a variety of medical conditions, including cerebral and cardiac ischemia, acute kidney injury, and transplantation. The aim of this study was to appraise the available evidence by systematically reviewing the literature and performing meta-analyses. PubMed, EMBASE, and the Cochrane Library. Inclusion criteria specified any articles on noble gases and either ischemia reperfusion injury or transplantation. In vitro studies, publications without full text, review articles, and letters were excluded. Information on noble gas, organ, species, model, length of ischemia, conditioning and noble gas dose, duration of administration of the gas, endpoints, and effects was extracted from 79 eligible articles. Study quality was evaluated using the Jadad scale. Effect sizes were extracted from the articles or retrieved from the authors to allow meta-analyses using the random-effects approach. Argon has been investigated in cerebral, myocardial, and renal ischemia reperfusion injury; helium and xenon have additionally been tested in hepatic ischemia reperfusion injury, whereas neon was only explored in myocardial ischemia reperfusion injury. The majority of studies show a protective effect of these noble gases on ischemia reperfusion injury across a broad range of experimental conditions, organs, and species. Overall study quality was low. Meta-analysis for argon was only possible in cerebral ischemia reperfusion injury and did not show neuroprotective effects. Helium proved neuroprotective in rodents and cardioprotective in rabbits, and there were too few data on renal ischemia reperfusion injury. Xenon had the most consistent effects, being neuroprotective in rodents, cardioprotective in rodents and pigs, and renoprotective in rodents. Helium and xenon show organ protective effects mostly in small animal ischemia reperfusion injury models. Additional information on timing, dosing, and

  12. Model-driven meta-analyses for informing health care: a diabetes meta-analysis as an exemplar.

    Science.gov (United States)

    Brown, Sharon A; Becker, Betsy Jane; García, Alexandra A; Brown, Adama; Ramírez, Gilbert

    2015-04-01

    A relatively novel type of meta-analysis, a model-driven meta-analysis, involves the quantitative synthesis of descriptive, correlational data and is useful for identifying key predictors of health outcomes and informing clinical guidelines. Few such meta-analyses have been conducted and thus, large bodies of research remain unsynthesized and uninterpreted for application in health care. We describe the unique challenges of conducting a model-driven meta-analysis, focusing primarily on issues related to locating a sample of published and unpublished primary studies, extracting and verifying descriptive and correlational data, and conducting analyses. A current meta-analysis of the research on predictors of key health outcomes in diabetes is used to illustrate our main points.

  13. Evidence from Meta-Analyses of the Facial Width-to-Height Ratio as an Evolved Cue of Threat.

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    Shawn N Geniole

    Full Text Available The facial width-to-height ratio (FWHR is the width of the face divided by the height of the upper face. There is mixed evidence for the hypothesis that the FWHR is a cue of threat and dominance in the human face. We conducted a systematic review and meta-analyses of all peer-reviewed studies (and 2 unpublished studies to estimate the magnitude of the sex difference in the FWHR, and the magnitude of the relationship between the FWHR and threatening and dominant behaviours and perceptions. Studies were eligible for inclusion if the authors reported an analysis involving the FWHR. Our analyses revealed that the FWHR was larger in men than in women (d = .11, n = 10,853, cued judgements of masculinity in men (r = .35, n of faces = 487; n of observers = 339, and was related to body mass index (r = .31, n = 2,506. Further, the FWHR predicted both threat behaviour in men (r = .16, n = 4,603 and dominance behaviour in both sexes (r = .12, n = 948 across a variety of indices. Individuals with larger FWHRs were judged by observers as more threatening (r = .46, n of faces = 1,691; n of observers = 2,076 and more dominant (r = .20, n of faces = 603; n of observers = 236 than those with smaller FWHRs. Individuals with larger FWHRs were also judged as less attractive (r = -.26, n of faces = 721; n of observers = 335, especially when women made the judgements. These findings provide some support for the hypothesis that the FWHR is part of an evolved cueing system of intra-sexual threat and dominance in men. A limitation of the meta-analyses on perceptions of threat and dominance were the low number of stimuli involving female and older adult faces.

  14. Effectiveness of pharmacotherapy for severe personality disorders: meta-analyses of randomized controlled trials.

    Science.gov (United States)

    Ingenhoven, Theo; Lafay, Patricia; Rinne, Thomas; Passchier, Jan; Duivenvoorden, Hugo

    2010-01-01

    There has been little systematic attempt to validate current pharmacologic treatment algorithms and guidelines for severe personality disorder. We evaluated studies on the effectiveness of psychoactive drugs on specific symptom domains for borderline and/or schizotypal personality disorder. The literature was searched for placebo-controlled randomized clinical trials (PC-RCTs) on the effectiveness of psychopharmacologic drugs in personality disorder patients. The PubMed, PsychINFO, PiCarta, Cochrane, and Web of Science databases were searched using the search terms borderline personality, schizotypal personality, personality disorder, cluster A, cluster B, treatment, drug, pharmacotherapy, antipsychotic, antidepressant, mood stabilizer, effect, outcome, review, and meta-analysis for studies published between 1980 and December 2007, and references were identified from bibliographies from articles and books. Placebo-controlled randomized clinical trials on the efficacy of antipsychotics, antidepressants, and mood stabilizers regarding cognitive-perceptual symptoms, impulsive-behavioral dyscontrol, and affective dysregulation (with subdomains depressed mood, anxiety, anger, and mood lability) were selected in patients with well defined borderline and/or schizotypal personality disorder. Studies whose primary emphasis was on the treatment of Axis I disorders were excluded. Meta-analyses were conducted using 21 retrieved studies. Antipsychotics have a moderate effect on cognitive-perceptual symptoms (5 PC-RCTs; standardized mean difference [SMD]=0.56) and a moderate to large effect on anger (4 PC-RCTs; SMD=0.69). Antidepressants have no significant effect on impulsive-behavioral dyscontrol and depressed mood. They have a small but significant effect on anxiety (5 PC-RCTs; SMD=0.30) and anger (4 PC-RCTs; SMD=0.34). Mood stabilizers have a very large effect on impulsive-behavioral dyscontrol (6 PC-RCTs; SMD=1.51) and anger (7 PC-RCTs; SMD=1.33), a large effect on anxiety

  15. Quality assessment and factor analysis of systematic reviews and meta-analyses of endoscopic ultrasound diagnosis.

    Directory of Open Access Journals (Sweden)

    Danlu Liu

    Full Text Available Comprehensive monitoring of the quality of systematic reviews (SRs and meta-analyses (MAs of endoscopic ultrasound (EUS requires complete and accurate reporting and methodology.To assess the reporting and methodological quality of SRs/MAs on EUS diagnosis and to explore the potential factors influencing articles' quality.The quality of the reporting and methodology was evaluated in relation to the adherence of papers to the PRISMA checklist and the AMSTAR quality scale. The total scores for every criterion and for every article on the two standards were calculated. Data were evaluated and analyzed using SPSS17.0 and RevMan 5.1 in terms of publication time, category of reviews, category of journals, and funding resource.A total of 72 SRs/MAs was included, but no Cochrane Systematic Reviews (CSRs were obtained. The number of SRs/MAs ranged from 1 in 1998 to 15 in 2013; 88.1% used the QUADAS tool; the average overall scores by PRISMA statement and AMSTAR tool were 19.9 and 5.4, respectively. Scores on some items showed substantial improvement after publication of PRISMA and AMSTAR. However, no reviews followed the criterion of protocol and registration, and only 11.1% of articles fulfilled the criterion of literature search. SRs/MAs from the Science Citation Index (SCI were of better quality than non-SCI studies. Funding resource made no difference to quality. Regression analysis showed that time of publication and inclusion in the SCI were significantly correlated with total scores on the two standards.The reporting and methodological quality of SRs/MAs on EUS diagnosis has improved measurably since PRISMA and AMSTAR checklists released. It is hoped that CSR in this field will be produced. Literature searching and protocol criteria, as well as QUADAS-2 tool need to be addressed more in the future. Time of publication and SCI relate more to the overall quality of SRs/MAs than does funding resource.

  16. The evidence from systematic reviews and meta-analyses published in orthodontic literature. Where do we stand?

    OpenAIRE

    Koletsi, Despina; Fleming, Padhraig S; Eliades, Theodore; Pandis, Nikolaos

    2015-01-01

    AIM: To analyse meta-analyses included in systematic reviews (SRs) published in leading orthodontic journals and the Cochrane Database of Systematic Reviews (CDSR) focusing on orthodontic literature and to assess the quality of the existing evidence. MATERIALS AND METHODS: Electronic searching was undertaken to identify SRs published in five major orthodontic journals and the CDSR between January 2000 and June 2014. Quality assessment of the overall body of evidence from meta-analyses was ...

  17. Saturated Fat Controversy: Importance of Systematic Reviews and Meta-analyses.

    Science.gov (United States)

    Szajewska, Hania; Szajewski, Tomasz

    2016-09-09

    In adults, worldwide, the number one cause of death is coronary heart disease. Current guidelines generally recommend reduced consumption of saturated fat to reduce the risk of cardiovascular disease. However, some evidence suggests that consumption of saturated fat does not increase that risk. Recently, to address the saturated fat controversy, i.e., whether or not saturated fat intake is a risk factor for cardiovascular disease, a number of systematic reviews and meta-analyses were performed. This paper aims to provide tools for understanding both. It starts with an overview of the basic principles of systematic reviews and meta-analyses. Then, it provides examples of current evidence from systematic reviews on the relationship between saturated fat intake and the risk of cardiovascular disease. Finally, based on an example from one recent systematic review, it explains how to read a meta-analysis. Continuous updating of existing reviews, as well as the development of new systematic reviews, is needed in areas in which the role of saturated fat remains unclear.

  18. The empirical status of cognitive-behavioral therapy: a review of meta-analyses.

    Science.gov (United States)

    Butler, Andrew C; Chapman, Jason E; Forman, Evan M; Beck, Aaron T

    2006-01-01

    This review summarizes the current meta-analysis literature on treatment outcomes of CBT for a wide range of psychiatric disorders. A search of the literature resulted in a total of 16 methodologically rigorous meta-analyses. Our review focuses on effect sizes that contrast outcomes for CBT with outcomes for various control groups for each disorder, which provides an overview of the effectiveness of cognitive therapy as quantified by meta-analysis. Large effect sizes were found for CBT for unipolar depression, generalized anxiety disorder, panic disorder with or without agoraphobia, social phobia, posttraumatic stress disorder, and childhood depressive and anxiety disorders. Effect sizes for CBT of marital distress, anger, childhood somatic disorders, and chronic pain were in the moderate range. CBT was somewhat superior to antidepressants in the treatment of adult depression. CBT was equally effective as behavior therapy in the treatment of adult depression and obsessive-compulsive disorder. Large uncontrolled effect sizes were found for bulimia nervosa and schizophrenia. The 16 meta-analyses we reviewed support the efficacy of CBT for many disorders. While limitations of the meta-analytic approach need to be considered in interpreting the results of this review, our findings are consistent with other review methodologies that also provide support for the efficacy CBT.

  19. A summary of two meta-analyses on neurobehavioural effects due to occupational lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Seeber, Andreas; Meyer-Baron, Monika; Schaeper, Michael [Institut fuer Arbeitsphysiologie, Universitaet Dortmund (Germany)

    2002-04-01

    The conclusions from published results about neurotoxic effects of inorganic lead exposures <700 {mu}g lead/l blood are contradictory at present. Effects measured by neurobehavioural methods are evaluated differently as far as recommendations for a Biological Exposure Index (BEI) of occupational lead exposure are concerned. Arguments against the German BEI of 400 {mu}g/l were put forward in new publications, and discussion of the issues is the aim of this article. It summarizes two different meta-analytical reviews on neurobehavioural effects in order to show the main tendencies of 24 selected publications on the matter. Calculations on effect sizes are compiled for 12 tests analysed in two meta-analyses and of ten tests analysed in one of the meta-analyses. The survey of six tests of learning and memory gives hints on impairments measured with two tests, covering Logical Memory and Visual Reproduction. The survey of seven tests of attention and visuospatial information processing describes impairments in four tests, namely Simple Reaction, Attention Test d2, Block Design, and Picture Completion. The survey of four tests for psychomotor functions shows impairments for three tests, namely Santa Ana, Grooved Pegboard, and Eye-hand Coordination. These test results provide evidence for subtle deficits being associated with average blood lead levels between 370 and 520 {mu}g/l. In evaluating the adversity of such effects it is concluded that the results of both meta-analytical reviews support the recommendation for the German BEI. (orig.)

  20. No evidence for genome-wide interactions on plasma fibrinogen by smoking, alcohol consumption and body mass index: results from meta-analyses of 80,607 subjects.

    Directory of Open Access Journals (Sweden)

    Jens Baumert

    Full Text Available Plasma fibrinogen is an acute phase protein playing an important role in the blood coagulation cascade having strong associations with smoking, alcohol consumption and body mass index (BMI. Genome-wide association studies (GWAS have identified a variety of gene regions associated with elevated plasma fibrinogen concentrations. However, little is yet known about how associations between environmental factors and fibrinogen might be modified by genetic variation. Therefore, we conducted large-scale meta-analyses of genome-wide interaction studies to identify possible interactions of genetic variants and smoking status, alcohol consumption or BMI on fibrinogen concentration. The present study included 80,607 subjects of European ancestry from 22 studies. Genome-wide interaction analyses were performed separately in each study for about 2.6 million single nucleotide polymorphisms (SNPs across the 22 autosomal chromosomes. For each SNP and risk factor, we performed a linear regression under an additive genetic model including an interaction term between SNP and risk factor. Interaction estimates were meta-analysed using a fixed-effects model. No genome-wide significant interaction with smoking status, alcohol consumption or BMI was observed in the meta-analyses. The most suggestive interaction was found for smoking and rs10519203, located in the LOC123688 region on chromosome 15, with a p value of 6.2 × 10(-8. This large genome-wide interaction study including 80,607 participants found no strong evidence of interaction between genetic variants and smoking status, alcohol consumption or BMI on fibrinogen concentrations. Further studies are needed to yield deeper insight in the interplay between environmental factors and gene variants on the regulation of fibrinogen concentrations.

  1. Statistical analysis of individual participant data meta-analyses: a comparison of methods and recommendations for practice.

    Directory of Open Access Journals (Sweden)

    Gavin B Stewart

    Full Text Available BACKGROUND: Individual participant data (IPD meta-analyses that obtain "raw" data from studies rather than summary data typically adopt a "two-stage" approach to analysis whereby IPD within trials generate summary measures, which are combined using standard meta-analytical methods. Recently, a range of "one-stage" approaches which combine all individual participant data in a single meta-analysis have been suggested as providing a more powerful and flexible approach. However, they are more complex to implement and require statistical support. This study uses a dataset to compare "two-stage" and "one-stage" models of varying complexity, to ascertain whether results obtained from the approaches differ in a clinically meaningful way. METHODS AND FINDINGS: We included data from 24 randomised controlled trials, evaluating antiplatelet agents, for the prevention of pre-eclampsia in pregnancy. We performed two-stage and one-stage IPD meta-analyses to estimate overall treatment effect and to explore potential treatment interactions whereby particular types of women and their babies might benefit differentially from receiving antiplatelets. Two-stage and one-stage approaches gave similar results, showing a benefit of using anti-platelets (Relative risk 0.90, 95% CI 0.84 to 0.97. Neither approach suggested that any particular type of women benefited more or less from antiplatelets. There were no material differences in results between different types of one-stage model. CONCLUSIONS: For these data, two-stage and one-stage approaches to analysis produce similar results. Although one-stage models offer a flexible environment for exploring model structure and are useful where across study patterns relating to types of participant, intervention and outcome mask similar relationships within trials, the additional insights provided by their usage may not outweigh the costs of statistical support for routine application in syntheses of randomised controlled

  2. Association of Helicobacter pylori infection with chronic atrophic gastritis: Meta-analyses according to type of disease definition.

    Science.gov (United States)

    Weck, Melanie N; Brenner, Hermann

    2008-08-15

    Helicobacter pylori is a major risk factor for chronic atrophic gastritis (CAG). A large variety of definitions of CAG have been used in epidemiologic studies in the past. The aim of this work was to systematically review and summarize estimates of the association between H. pylori infection and CAG according to the various definitions of CAG. Articles on the association between H. pylori infection and CAG published until July 2007 were identified. Separate meta-analyses were carried out for studies defining CAG based on gastroscopy with biopsy, serum pepsinogen I (PG I) only, the pepsinogen I/pepsinogen II ratio (PG I/PG II ratio) only, or a combination of PG I and the PG I/PG II ratio. Numbers of identified studies and summary odds ratios (OR) (95% confidence intervals) were as follows: gastroscopy with biopsy: n = 34, OR = 6.4 (4.0-10.1); PG I only: n = 13, OR = 0.9 (0.7-1.2); PG I/PG II ratio: n = 8, OR = 7.2 (3.1-16.8); combination of PG I and the PG I/PG II ratio: n = 20, OR = 5.7 (4.4-7.5). Studies with CAG definitions based on gastroscopy with biopsy or the PG I/PG II ratio (alone or in combination with PG I) yield similarly strong associations of H. pylori with CAG. The association is missed entirely in studies where CAG is defined by PG I only.

  3. Developing a library of display effects on pilot performance: Methods, meta-analyses, and performance estimates

    Science.gov (United States)

    Salud, Ellen

    The design of NextGen and current-day cockpit displays are critical for efficient pilot performance and situation awareness on the flight deck. Before deployment of a design into the cockpit the costs and benefits that a display design imposes on performance and situation awareness should be considered. In this thesis, a design tool was developed to support the design of NextGen displays for situation awareness and performance. This design tool is a library of pilot performance estimates. Through literature reviews and meta-analyses of empirical data, the library was developed to provide display designers 1) qualitative distinctions of display properties that either support or limit full situation awareness, and 2) quantitative performance time estimates until situation awareness as a function of various display formats. A systematic method was also developed for future augmentation of the library.

  4. Visible learning a synthesis of over 800 meta-analyses relating to achievement

    CERN Document Server

    Hattie, John A C

    2009-01-01

    This unique and ground-breaking book is the result of 15 years research and synthesises over 800 meta-analyses on the influences on achievement in school-aged students. It builds a story about the power of teachers, feedback, and a model of learning and understanding. The research involves many millions of students and represents the largest ever evidence based research into what actually works in schools to improve learning. Areas covered include the influence of the student, home, school, curricula, teacher, and teaching strategies. A model of teaching and learning is developed based on the notion of visible teaching and visible learning. A major message is that what works best for students is similar to what works best for teachers - an attention to setting challenging learning intentions, being clear about what success means, and an attention to learning strategies for developing conceptual understanding about what teachers and students know and understand. Although the current evidence based fad has turn...

  5. Behavioral treatments for speech in Parkinson's disease: meta-analyses and review of the literature.

    Science.gov (United States)

    Atkinson-Clement, Cyril; Sadat, Jasmin; Pinto, Serge

    2015-01-01

    Parkinson's disease (PD) results from neurodegenerative processes leading to alteration of motor functions. Most motor symptoms respond well to pharmacological and neurosurgical treatments, except some axial symptoms such as speech impairment, so-called dysarthria. However, speech therapy is rarely proposed to PD patients. This review aims at evaluating previous research on the effects of speech behavioral therapies in patients with PD. We also performed two meta-analyses focusing on speech loudness and voice pitch. We showed that intensive therapies in PD are the most effective for hypophonia and can lead to some improvement of voice pitch. Although speech therapy is effective in handling PD dysarthria, behavioral speech rehabilitation in PD still needs further validation.

  6. The PRISMA extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions

    DEFF Research Database (Denmark)

    Hutton, Brian; Salanti, Georgia; Caldwell, Deborah M;

    2015-01-01

    The PRISMA statement is a reporting guideline designed to improve the completeness of reporting of systematic reviews and meta-analyses. Authors have used this guideline worldwide to prepare their reviews for publication. In the past, these reports typically compared 2 treatment alternatives...... to improve the reporting of systematic reviews incorporating network meta-analyses. A group of experts participated in a systematic review, Delphi survey, and face-to-face discussion and consensus meeting to establish new checklist items for this extension statement. Current PRISMA items were also clarified....... With the evolution of systematic reviews that compare multiple treatments, some of them only indirectly, authors face novel challenges for conducting and reporting their reviews. This extension of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) statement was developed specifically...

  7. Malignancy risk of anti-tumor necrosis factor alpha blockers: an overview of systematic reviews and meta-analyses.

    Science.gov (United States)

    Chen, Yuehong; Sun, Jianhong; Yang, Yuan; Huang, Yupeng; Liu, Gang

    2016-01-01

    The objective of the study is to systematically review the malignancy risk of anti-tumor necrosis factor alpha (anti-TNFα) agents. Databases of PubMed Medline, OVID EMBASE, and Cochrane Library were searched to identify published systematic reviews and meta-analyses of randomized control trials, observational studies, and case series that evaluated malignancy risk of anti-TNFα blockers. Search time duration was restricted from January 1st, 2000 to July 16th, 2015. Overview Quality Assessment Questionnaires were used to assess the quality of included reviews. Two methodology trained reviewers separately and repeatedly screened searched studies according to study selection criteria, collected data, and assessed quality. Totally, 42 reviews proved eligible with only one Cochrane review. Anti-TNFα antagonists were extensively used to treat various diseases; nevertheless, malignancy risks were most commonly described in patients with rheumatoid arthritis (RA) and inflammatory bowel disease (IBD). In RA patients, no increased risks of breast cancer, lymphoma, and non-melanoma skin cancer were found, but if the use of anti-TNFα agents was associated with elevated risk of overall malignancy was still uncertainty. In IBD patients, the use of anti-TNFα inhibitors was not connected with enhanced risk of overall cancer. No increased cancer risk was found in other disease conditions. Twenty-nine reviews were rated as good quality, 12 as moderate, and one as poor. There are no sufficient evidences to draw the conclusion that anti-TNFα blockers have relationship with increased malignancy risk.

  8. Airway management education: simulation based training versus non-simulation based training-A systematic review and meta-analyses.

    Science.gov (United States)

    Sun, Yanxia; Pan, Chuxiong; Li, Tianzuo; Gan, Tong J

    2017-02-01

    Simulation-based training (SBT) has become a standard for medical education. However, the efficacy of simulation based training in airway management education remains unclear. The aim of this study was to evaluate all published evidence comparing the effectiveness of SBT for airway management versus non-simulation based training (NSBT) on learner and patient outcomes. Systematic review with meta-analyses were used. Data were derived from PubMed, EMBASE, CINAHL, Scopus, the Cochrane Controlled Trials Register and Cochrane Database of Systematic Reviews from inception to May 2016. Published comparative trials that evaluated the effect of SBT on airway management training in compared with NSBT were considered. The effect sizes with 95% confidence intervals (CI) were calculated for outcomes measures. Seventeen eligible studies were included. SBT was associated with improved behavior performance [standardized mean difference (SMD):0.30, 95% CI: 0.06 to 0.54] in comparison with NSBT. However, the benefits of SBT were not seen in time-skill (SMD:-0.13, 95% CI: -0.82 to 0.52), written examination score (SMD: 0.39, 95% CI: -0.09 to 0.86) and success rate of procedure completion on patients [relative risk (RR): 1.26, 95% CI: 0.96 to 1.66]. SBT may be not superior to NSBT on airway management training.

  9. Systematic Review and Meta-Analyses of Perinatal Death and Maternal Exposure to Tobacco Smoke During Pregnancy.

    Science.gov (United States)

    Pineles, Beth L; Hsu, Sarah; Park, Edward; Samet, Jonathan M

    2016-07-15

    We conducted a systematic review and 3-part meta-analysis to characterize the relationship between smoking and perinatal death, defined as the combination of stillbirth and neonatal death. The PubMed database was searched (1956-August 31, 2011) with keywords, and manual reference searches of included articles and Surgeon Generals' reports were conducted. The full texts of 1,713 articles were reviewed, and 142 articles that examined the associations between active or passive smoking and perinatal death were included in the meta-analyses. Data were abstracted by 2 reviewers. Any active maternal smoking was associated with increased risks of stillbirth (summary relative risk (sRR) = 1.46, 95% confidence interval (CI): 1.38, 1.54 (n = 57 studies)), neonatal death (sRR = 1.22, 95% CI: 1.14, 1.30 (n = 28)), and perinatal death (sRR = 1.33, 95% CI: 1.25, 1.41 (n = 46)). The risks of stillbirth, neonatal death, and perinatal death increased with the amount smoked by the mother. Biases in study publication, design, and analysis were present but did not significantly affect the results. These findings strengthen the evidence that women should not smoke while pregnant, and all women of reproductive age should be warned that smoking increases the risks of stillbirth, neonatal death, and perinatal death.

  10. The role of diet and lifestyle in primary, secondary, and tertiary diabetes prevention: a review of meta-analyses.

    Science.gov (United States)

    Psaltopoulou, Theodora; Ilias, Ioannis; Alevizaki, Maria

    2010-01-01

    Prevention of diabetes is crucial to lowering disease incidence, and thus minimizing the individual, familial, and public health burden. The purpose of this review is to gather current information from meta-analyses on dietary and lifestyle practices concerning reduction of risk to develop type 2 diabetes. Low glycemic index dietary patterns reduce both fasting blood glucose and glycated proteins independent of carbohydrate consumption. Diets rich in whole-grain, cereal high fiber products, and non-oil-seed pulses are beneficial. Whereas, frequent meat consumption has been shown to increase risk. Regarding non-alcoholic beverages, 4 cups/day of filtered coffee or tea are associated with a reduced diabetes risk. In contrast, the consumption of alcoholic beverages should not exceed 1-3 drinks/day. Intake of vitamin E, carotenoids, and magnesium can be increased to counteract diabetes risk. Obesity is the most important factor accounting for more than half of new diabetes' cases; even modest weight loss has a favorable effect in preventing the appearance of diabetes. Also, physical exercise with or without diet contributes to a healthier lifestyle, and is important for lowering risk. Finally, there is a positive association between smoking and risk to develop type 2 diabetes. As far as secondary and tertiary prevention is concerned, for persons already diagnosed with diabetes, there is limited evidence of the effectiveness of diet or lifestyle modification on glycemic control, but further studies are necessary.

  11. Meta-analyses of the relationship between conformity to masculine norms and mental health-related outcomes.

    Science.gov (United States)

    Wong, Y Joel; Ho, Moon-Ho Ringo; Wang, Shu-Yi; Miller, I S Keino

    2017-01-01

    Despite theoretical postulations that individuals' conformity to masculine norms is differentially related to mental health-related outcomes depending on a variety of contexts, there has not been any systematic synthesis of the empirical research on this topic. Therefore, the authors of this study conducted meta-analyses of the relationships between conformity to masculine norms (as measured by the Conformity to Masculine Norms Inventory-94 and other versions of this scale) and mental health-related outcomes using 78 samples and 19,453 participants. Conformity to masculine norms was modestly and unfavorably associated with mental health as well as moderately and unfavorably related to psychological help seeking. The authors also identified several moderation effects. Conformity to masculine norms was more strongly correlated with negative social functioning than with psychological indicators of negative mental health. Conformity to the specific masculine norms of self-reliance, power over women, and playboy were unfavorably, robustly, and consistently related to mental health-related outcomes, whereas conformity to the masculine norm of primacy of work was not significantly related to any mental health-related outcome. These findings highlight the need for researchers to disaggregate the generic construct of conformity to masculine norms and to focus instead on specific dimensions of masculine norms and their differential associations with other outcomes. (PsycINFO Database Record

  12. Laterality interacts with sex across the schizophrenia/bipolarity continuum: an interpretation of meta-analyses of structural MRI.

    Science.gov (United States)

    Crow, Timothy J; Chance, Steven A; Priddle, Thomas H; Radua, Joaquim; James, Anthony C

    2013-12-30

    Review of the first comprehensive meta-analysis of VBM (voxel-based morphometry) studies in schizophrenia indicates asymmetrical reductions of anterior cingulate gyrus to the right, and medial temporal lobe (including the uncus) and para-hippocampal gyrus to the left. In subsequent meta-analyses of schizophrenia and bipolar disorder change in these limbic structures is systematically related to change in the insula. Deficits in insula (and para-hippocampal gyrus) to the left, and dorsal anterior cingulate gyrus to the right are greater in schizophrenic psychoses whereas deficits in anterior cingulate to the left and insula to the right are greater in bipolar illness. Thus (1) brain structures implicated in schizophrenia include those implicated in bipolar disorder, (2) the variation that separates the prototypical psychoses may be a subset of that relating to the structural asymmetry (the "torque") characteristic of the human brain, and (3) the meta-analysis of Bora et al. (2012) indicates that laterality of involvement of the insula and cingulate gyrus across the spectrum of bipolar and schizophrenic psychoses is critically dependent upon the sex ratio. Thus structural change underlying the continuum of psychosis relates to the interaction of laterality and sex.

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

    DEFF Research Database (Denmark)

    Brok, Jesper; Thorlund, Kristian; Wetterslev, Jørn;

    2008-01-01

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

  14. Robustness assessments are needed to reduce bias in meta-analyses that include zero-event randomized trials.

    NARCIS (Netherlands)

    Keus, F.; Wetterslev, J.; Gluud, C.; Gooszen, H.G.; Laarhoven, C.J.H.M. van

    2009-01-01

    OBJECTIVES: Meta-analysis of randomized trials with binary data can use a variety of statistical methods. Zero-event trials may create analytic problems. We explored how different methods may impact inferences from meta-analyses containing zero-event trials. METHODS: Five levels of statistical metho

  15. Robustness Assessments Are Needed to Reduce Bias in Meta-Analyses That Include Zero-Event Randomized Trials

    NARCIS (Netherlands)

    Keus, F.; Wetterslev, J.; Gluud, C.; Gooszen, H. G.; van Laarhoven, C. J. H. M.

    2009-01-01

    OBJECTIVES: Meta-analysis of randomized trials with binary data can use a variety of statistical methods. Zero-event trials may create analytic problems. We explored how different methods may impact inferences from meta-analyses containing zero-event trials. METHODS: Five levels of statistical metho

  16. A Model for Integrating Fixed-, Random-, and Mixed-Effects Meta-Analyses into Structural Equation Modeling

    Science.gov (United States)

    Cheung, Mike W.-L.

    2008-01-01

    Meta-analysis and structural equation modeling (SEM) are two important statistical methods in the behavioral, social, and medical sciences. They are generally treated as two unrelated topics in the literature. The present article proposes a model to integrate fixed-, random-, and mixed-effects meta-analyses into the SEM framework. By applying an…

  17. Reflections on meta-analyses involving trials stopped early for benefit: is there a problem and if so, what is it?

    Science.gov (United States)

    Bassler, Dirk; Montori, Victor M; Briel, Matthias; Glasziou, Paul; Walter, Stephen D; Ramsay, Tim; Guyatt, Gordon

    2013-04-01

    We review controversies associated with randomized controlled trials (RCTs) stopped early for apparent benefit (truncated RCTs or tRCTs) and present our groups' perspective. Long-established theory, simulations and recent empirical evidence demonstrate that tRCTs will on average overestimate treatment effects, and this overestimation may be large, particularly when tRCTs have small number of events. Theoretical considerations and simulations demonstrate that on average, meta-analyses of RCTs with appropriate stopping rules will lead to only trivial overestimation of treatment effects. However, tRCTs will disproportionally contribute to meta-analytic estimates when tRCTs occur early in the sequence of trials with few subsequent studies, publication of nontruncated RCTs is delayed, there is publication bias, or tRCTs result in a 'freezing' effect in which 'correcting' trials are never undertaken. To avoid applying overestimates of effect to clinical decision-making, clinicians should view the results of individual tRCTs with small sample sizes and small number of events with skepticism. Pooled effects from meta-analyses including tRCTs are likely to overestimate effect when there is a substantial difference in effect estimates between the tRCTs and the nontruncated RCTs, and in which the tRCTs have a substantial weight in the meta-analysis despite themselves having a relatively small number of events. Such circumstances call for sensitivity analyses omitting tRCTs.

  18. Soil carbon response to land-use change: evaluation of a global vegetation model using observational meta-analyses

    Science.gov (United States)

    Nyawira, Sylvia S.; Nabel, Julia E. M. S.; Don, Axel; Brovkin, Victor; Pongratz, Julia

    2016-10-01

    Global model estimates of soil carbon changes from past land-use changes remain uncertain. We develop an approach for evaluating dynamic global vegetation models (DGVMs) against existing observational meta-analyses of soil carbon changes following land-use change. Using the DGVM JSBACH, we perform idealized simulations where the entire globe is covered by one vegetation type, which then undergoes a land-use change to another vegetation type. We select the grid cells that represent the climatic conditions of the meta-analyses and compare the mean simulated soil carbon changes to the meta-analyses. Our simulated results show model agreement with the observational data on the direction of changes in soil carbon for some land-use changes, although the model simulated a generally smaller magnitude of changes. The conversion of crop to forest resulted in soil carbon gain of 10 % compared to a gain of 42 % in the data, whereas the forest-to-crop change resulted in a simulated loss of -15 % compared to -40 %. The model and the observational data disagreed for the conversion of crop to grasslands. The model estimated a small soil carbon loss (-4 %), while observational data indicate a 38 % gain in soil carbon for the same land-use change. These model deviations from the observations are substantially reduced by explicitly accounting for crop harvesting and ignoring burning in grasslands in the model. We conclude that our idealized simulation approach provides an appropriate framework for evaluating DGVMs against meta-analyses and that this evaluation helps to identify the causes of deviation of simulated soil carbon changes from the meta-analyses.

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

    DEFF Research Database (Denmark)

    Wetterslev, Jørn; Thorlund, Kristian; Brok, Jesper;

    2009-01-01

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

  20. Trial sequential analyses of meta-analyses of complications in laparoscopic vs. small-incision cholecystectomy: more randomized patients are needed

    DEFF Research Database (Denmark)

    Keus, Frederik; Wetterslev, Jørn; Gluud, Christian;

    2010-01-01

    Conclusions based on meta-analyses of randomized trials carry a status of "truth." Methodological components may identify trials with systematic errors ("bias"). Trial sequential analysis (TSA) evaluates random errors in meta-analysis. We analyzed meta-analyses on laparoscopic vs. small-incision...

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

    Science.gov (United States)

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

    2010-01-01

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

  2. [Individual patient data meta-analyses of randomized trials for the treatment of non-metastatic head and neck squamous cell carcinomas: Principles, results and perspectives].

    Science.gov (United States)

    Blanchard, P; Bourhis, J; Lacas, B; Le Teuff, G; Michiels, S; Pignon, J-P

    2015-05-01

    Meta-analyses are considered as an important pillar of evidence-based medicine. The aim of this review is to describe the main principles of a meta-analysis and to use examples of head and neck oncology to demonstrate their clinical impact and methodological interest. The major role of individual patient data is outlined, as well as the superiority of individual patient data over meta-analyses based on published summary data. The major clinical breakthrough of head and neck meta-analyses are summarized, regarding concomitant chemotherapy, altered fractionated chemotherapy, new regimens of induction chemotherapy or the use of radioprotectants. Recent methodological developments are described, including network meta-analyses, the validation of surrogate markers. Lastly, the future of meta-analyses is discussed in the context of personalized medicine.

  3. Author-paper affiliation network architecture influences the methodological quality of systematic reviews and meta-analyses of psoriasis.

    Science.gov (United States)

    Sanz-Cabanillas, Juan Luis; Ruano, Juan; Gomez-Garcia, Francisco; Alcalde-Mellado, Patricia; Gay-Mimbrera, Jesus; Aguilar-Luque, Macarena; Maestre-Lopez, Beatriz; Gonzalez-Padilla, Marcelino; Carmona-Fernandez, Pedro J; Velez Garcia-Nieto, Antonio; Isla-Tejera, Beatriz

    2017-01-01

    Moderate-to-severe psoriasis is associated with significant comorbidity, an impaired quality of life, and increased medical costs, including those associated with treatments. Systematic reviews (SRs) and meta-analyses (MAs) of randomized clinical trials are considered two of the best approaches to the summarization of high-quality evidence. However, methodological bias can reduce the validity of conclusions from these types of studies and subsequently impair the quality of decision making. As co-authorship is among the most well-documented forms of research collaboration, the present study aimed to explore whether authors' collaboration methods might influence the methodological quality of SRs and MAs of psoriasis. Methodological quality was assessed by two raters who extracted information from full articles. After calculating total and per-item Assessment of Multiple Systematic Reviews (AMSTAR) scores, reviews were classified as low (0-4), medium (5-8), or high (9-11) quality. Article metadata and journal-related bibliometric indices were also obtained. A total of 741 authors from 520 different institutions and 32 countries published 220 reviews that were classified as high (17.2%), moderate (55%), or low (27.7%) methodological quality. The high methodological quality subnetwork was larger but had a lower connection density than the low and moderate methodological quality subnetworks; specifically, the former contained relatively fewer nodes (authors and reviews), reviews by authors, and collaborators per author. Furthermore, the high methodological quality subnetwork was highly compartmentalized, with several modules representing few poorly interconnected communities. In conclusion, structural differences in author-paper affiliation network may influence the methodological quality of SRs and MAs on psoriasis. As the author-paper affiliation network structure affects study quality in this research field, authors who maintain an appropriate balance between

  4. Can simply answering research questions change behaviour? Systematic review and meta analyses of brief alcohol intervention trials.

    Directory of Open Access Journals (Sweden)

    Jim McCambridge

    Full Text Available BACKGROUND: Participant reports of their own behaviour are critical for the provision and evaluation of behavioural interventions. Recent developments in brief alcohol intervention trials provide an opportunity to evaluate longstanding concerns that answering questions on behaviour as part of research assessments may inadvertently influence it and produce bias. The study objective was to evaluate the size and nature of effects observed in randomized manipulations of the effects of answering questions on drinking behaviour in brief intervention trials. METHODOLOGY/PRINCIPAL FINDINGS: Multiple methods were used to identify primary studies. Between-group differences in total weekly alcohol consumption, quantity per drinking day and AUDIT scores were evaluated in random effects meta-analyses. Ten trials were included in this review, of which two did not provide findings for quantitative study, in which three outcomes were evaluated. Between-group differences were of the magnitude of 13.7 (-0.17 to 27.6 grams of alcohol per week (approximately 1.5 U.K. units or 1 standard U.S. drink and 1 point (0.1 to 1.9 in AUDIT score. There was no difference in quantity per drinking day. CONCLUSIONS/SIGNIFICANCE: Answering questions on drinking in brief intervention trials appears to alter subsequent self-reported behaviour. This potentially generates bias by exposing non-intervention control groups to an integral component of the intervention. The effects of brief alcohol interventions may thus have been consistently under-estimated. These findings are relevant to evaluations of any interventions to alter behaviours which involve participant self-report.

  5. Meta-analyses of comparative efficacy of antidepressant medications on peripheral BDNF concentration in patients with depression

    Science.gov (United States)

    Chen, Jianjun; Deng, Xiao; Zhang, Lin; Zhao, Xiang; Qu, Zehui; Lei, Yang; Lei, Ting

    2017-01-01

    Background Brain derived neurotrophic factor (BDNF) is one of the most important regulatory proteins in the pathophysiology of major depressive disorder (MDD). Increasing numbers of studies have reported the relationship between serum/plasma BDNF and antidepressants (ADs). However, the potential effects of several classes of antidepressants on BDNF concentrations are not well known. Hence, our meta-analyses aims to review the effects of differential antidepressant drugs on peripheral BDNF levels in MDD and make some recommendations for future research. Methods Electronic databases including PubMed, EMBASE, the Cochrane Library, Web of Science, and PsycINFO were searched from 1980 to June 2016. The change in BDNF levels were compared between baseline and post-antidepressants treatment by use of the standardized mean difference (SMD) with 95% confidence intervals (CIs). All statistical tests were two-sided. Results We identified 20 eligible trials of antidepressants treatments for BDNF in MDD. The overall effect size for all drug classes showed that BDNF levels were elevated following a course of antidepressants use. For between-study heterogeneity by stratification analyses, we detect that length of treatment and blood samples are significant effect modifiers for BDNF levels during antidepressants treatment. While both SSRIs and SNRIs could increase the BDNF levels after a period of antidepressant medication treatment, sertraline was superior to other three drugs (venlafaxine, paroxetine or escitalopram) in the early increase of BDNF concentrations with SMD 0.53(95% CI = 0.13–0.93; P = 0.009). Conclusions There is some evidence that treatment of antidepressants appears to be effective in the increase of peripheral BDNF levels. More robust evidence indicates that different types of antidepressants appear to induce differential effects on the BDNF levels. Since sertraline makes a particular effect on BDNF concentration within a short amount of time, there is

  6. Genome-wide meta-analyses identify multiple loci associated with smoking behavior.

    LENUS (Irish Health Repository)

    2010-05-01

    Consistent but indirect evidence has implicated genetic factors in smoking behavior. We report meta-analyses of several smoking phenotypes within cohorts of the Tobacco and Genetics Consortium (n = 74,053). We also partnered with the European Network of Genetic and Genomic Epidemiology (ENGAGE) and Oxford-GlaxoSmithKline (Ox-GSK) consortia to follow up the 15 most significant regions (n > 140,000). We identified three loci associated with number of cigarettes smoked per day. The strongest association was a synonymous 15q25 SNP in the nicotinic receptor gene CHRNA3 (rs1051730[A], beta = 1.03, standard error (s.e.) = 0.053, P = 2.8 x 10(-73)). Two 10q25 SNPs (rs1329650[G], beta = 0.367, s.e. = 0.059, P = 5.7 x 10(-10); and rs1028936[A], beta = 0.446, s.e. = 0.074, P = 1.3 x 10(-9)) and one 9q13 SNP in EGLN2 (rs3733829[G], beta = 0.333, s.e. = 0.058, P = 1.0 x 10(-8)) also exceeded genome-wide significance for cigarettes per day. For smoking initiation, eight SNPs exceeded genome-wide significance, with the strongest association at a nonsynonymous SNP in BDNF on chromosome 11 (rs6265[C], odds ratio (OR) = 1.06, 95% confidence interval (Cl) 1.04-1.08, P = 1.8 x 10(-8)). One SNP located near DBH on chromosome 9 (rs3025343[G], OR = 1.12, 95% Cl 1.08-1.18, P = 3.6 x 10(-8)) was significantly associated with smoking cessation.

  7. Efficacy and acceptability of very low energy diets in overweight and obese people with Type 2 diabetes mellitus: a systematic review with meta-analyses.

    Science.gov (United States)

    Rehackova, L; Arnott, B; Araujo-Soares, V; Adamson, A A; Taylor, R; Sniehotta, F F

    2016-05-01

    To explore the efficacy and acceptability of very low energy diets in overweight or obese adults with Type 2 diabetes. Controlled trials and qualitative studies of individuals with Type 2 diabetes that compared very low energy diets with standard care, minimal interventions, other weight loss interventions, less intensive very low energy diet interventions and very low energy diets with additional components were eligible for inclusion. Meta-analyses of changes in weight, blood glucose levels and attrition rates were performed. Acceptability of very low energy diets was assessed by attrition rates, number and severity of side effects, and by qualitative evaluations of the interventions. Four randomized, five non-randomized controlled trials and no qualitative studies (21 references, 9 studies, 346 participants) were identified. Meta-analyses showed that very low energy diets induced greater weight losses than minimal interventions, standard care or low energy diets at 3 and 6 months. No conclusive evidence for differences in outcomes between very low energy diets and Roux-en-Y gastric bypass surgery was found. Greater differences in energy prescription between intervention and comparator arms were associated with greater differences in weight loss and fasting blood glucose levels at 3 months. Attrition rates did not differ between the very low energy diets and the comparator arms at any measurement point. Very low energy diets are effective in substantial weight loss among people with Type 2 diabetes. Levels of adherence to very low energy diets in controlled studies appear to be high, although details about behaviour support provided are usually poorly described. © 2015 Diabetes UK.

  8. Systematic reviews and meta-analyses of home telemonitoring interventions for patients with chronic diseases: a critical assessment of their methodological quality.

    Science.gov (United States)

    Kitsiou, Spyros; Paré, Guy; Jaana, Mirou

    2013-07-23

    Systematic reviews and meta-analyses of home telemonitoring interventions for patients with chronic diseases have increased over the past decade and become increasingly important to a wide range of clinicians, policy makers, and other health care stakeholders. While a few criticisms about their methodological rigor and synthesis approaches have recently appeared, no formal appraisal of their quality has been conducted yet. The primary aim of this critical review was to evaluate the methodology, quality, and reporting characteristics of prior reviews that have investigated the effects of home telemonitoring interventions in the context of chronic diseases. Ovid MEDLINE, the Database of Abstract of Reviews of Effects (DARE), and Health Technology Assessment Database (HTA) of the Cochrane Library were electronically searched to find relevant systematic reviews, published between January 1966 and December 2012. Potential reviews were screened and assessed for inclusion independently by three reviewers. Data pertaining to the methods used were extracted from each included review and examined for accuracy by two reviewers. A validated quality assessment instrument, R-AMSTAR, was used as a framework to guide the assessment process. Twenty-four reviews, nine of which were meta-analyses, were identified from more than 200 citations. The bibliographic search revealed that the number of published reviews has increased substantially over the years in this area and although most reviews focus on studying the effects of home telemonitoring on patients with congestive heart failure, researcher interest has extended to other chronic diseases as well, such as diabetes, hypertension, chronic obstructive pulmonary disease, and asthma. Nevertheless, an important number of these reviews appear to lack optimal scientific rigor due to intrinsic methodological issues. Also, the overall quality of reviews does not appear to have improved over time. While several criteria were met

  9. Should we prescribe blood pressure lowering drugs to every patient with advanced chronic kidney disease? A comment on two recent meta-analyses.

    Science.gov (United States)

    Gross, Peter; Schirutschke, Holger; Barnett, Kerstin

    2009-10-01

    Antihypertensive treatment is an essential, life-prolonging measure in primary hypertension. It prevents apoplexy, myocardial infarction, and hypertensive kidney failure. Chronic kidney failure is associated with hypertension and an accelerated form of arteriosclerosis. Demise from cardiovascular affliction is a leading cause of death in renal patients (chronic renal failure stages II-IV, renal failure requiring dialysis, renal transplantation). What, then, is the role of antihypertensive treatment in such patients, and, specifically, what is achieved by renin-angiotensin-aldosterone (RAA) system modifying agents? Two meta-analyses have recently investigated these issues. An article in The Lancet evaluated eight studies on dialysis patients (n = 1679). It concluded that antihypertensives are beneficial in reducing cardiovascular morbidity and mortality. However, we criticize these conclusions and show that the data are not convincingly in favor of antihypertensive treatment. A meta-analysis in the American Heart Journal assessed the role of antihypertensive agents and RAA system modifying drugs in 45,758 patients (from 25 studies), who were in stages I-III of renal failure, i.e., not (yet) requiring dialysis. The authors claim that angiotensin- -converting enzyme inhibitors/angiotensin receptor blockers (ACEI/ARB) significantly reduced cardiovascular outcomes. However, our analysis of the data is not consistent with their conclusions. It showed that the results were quite mixed, that the authors may have overemphasized the positive results, and that considering all the results, it should be concluded that antihypertensive treatments, including those with ACEI/ARB, may not be superior to placebo (sic!) in renal patients. Rather than doing meta-analyses, larger primary studies are needed to reveal the real role of antihypertensive treatments in renal patients.

  10. The effect of grinding on the mechanical behavior of Y-TZP ceramics: A systematic review and meta-analyses.

    Science.gov (United States)

    Pereira, G K R; Fraga, S; Montagner, A F; Soares, F Z M; Kleverlaan, C J; Valandro, L F

    2016-10-01

    The aim of this study was to systematically review the literature to assess the effect of grinding on the mechanical properties, structural stability and superficial characteristics of Y-TZP ceramics. The MEDLINE via PubMed and Web of Science (ISI - Web of Knowledge) electronic databases were searched with included peer-reviewed publications in English language and with no publication year limit. From 342 potentially eligible studies, 73 were selected for full-text analysis, 30 were included in the systematic review with 20 considered in the meta-analysis. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias. Statistical analyses were performed using RevMan 5.1, with random effects model, at a significance level of 0.05. A descriptive analysis considering phase transformation, Y-TZP grain size, Vickers hardness, residual stress and aging of all included studies were executed. Four outcomes were considered in the meta-analyses (factor: grinding x as-sintered) in global and subgroups analyses (grinding tool, grit-size and cooling) for flexural strength and roughness (Ra) data. A significant difference (p<0.05) was observed in the global analysis for strength, favoring as-sintered; subgroup analyses revealed that different parameters lead to different effects on strength. In the global analysis for roughness, a significant difference (p<0.05) was observed between conditions, favoring grinding; subgroup analyses revealed that different parameters also lead to different effects on roughness. High heterogeneity was found in some comparisons. Generally grinding promotes decrease in strength and increase in roughness of Y-TZP ceramics. However, the use of a grinding tool that allows greater accuracy of the movement (i.e. contra angle hand-pieces coupled to slowspeed turbines), small grit size (<50μm) and the use of plenty coolant seem to be the main factors to decrease the defect introduction and allow the occurrence of the

  11. Interactions among Candidate Genes Selected by Meta-Analyses Resulting in Higher Risk of Ischemic Stroke in a Chinese Population.

    Directory of Open Access Journals (Sweden)

    Man Luo

    Full Text Available Ischemic stroke (IS is a multifactorial disorder caused by both genetic and environmental factors. The combined effects of multiple susceptibility genes might result in a higher risk for IS than a single gene. Therefore, we investigated whether interactions among multiple susceptibility genes were associated with an increased risk of IS by evaluating gene polymorphisms identified in previous meta-analyses, including methylenetetrahydrofolate reductase (MTHFR C677T, beta fibrinogen (FGB, β-FG A455G and T148C, apolipoprotein E (APOE ε2-4, angiotensin-converting enzyme (ACE insertion/deletion (I/D, and endothelial nitric oxide synthase (eNOS G894T. In order to examine these interactions, 712 patients with IS and 774 controls in a Chinese Han population were genotyped using the SNaPshot method, and multifactor dimensionality reduction analysis was used to detect potential interactions among the candidate genes. The results of this study found that ACE I/D and β-FG T148C were significant synergistic contributors to IS. In particular, the ACE DD + β-FG 148CC, ACE DD + β-FG 148CT, and ACE ID + β-FG 148CC genotype combinations resulted in higher risk of IS. After adjusting for potential confounding IS risk factors (age, gender, family history of IS, hypertension history and history of diabetes mellitus using a logistic analysis, a significant correlation between the genotype combinations and IS patients persisted (overall stroke: adjusted odds ratio [OR] = 1.57, 95% confidence interval [CI]: 1.22-2.02, P < 0.001, large artery atherosclerosis subtype: adjusted OR = 1.50, 95% CI: 1.08-2.07, P = 0.016, small-artery occlusion subtype: adjusted OR = 2.04, 95% CI: 1.43-2.91, P < 0.001. The results of this study indicate that the ACE I/D and β-FG T148C combination may result in significantly higher risk of IS in this Chinese population.

  12. Using systematic reviews and meta-analyses to support regulatory decision making for neurotoxicants: lessons learned from a case study of PCBs Utilizando revisões sistemáticas e meta-análise de apoio às decisões regulatórias para neurotóxicos: lições de um estudo de caso dos PCBs

    Directory of Open Access Journals (Sweden)

    Michael Goodman

    2011-07-01

    Full Text Available We examined prospective cohort studies evaluating the relation between prenatal and neonatal exposure to polychlorinated biphenyls (PCBs and neurodevelopment in children to assess the feasibility of conducting a meta-analysis to support decision making. We described studies in terms of exposure and end point categorization, statistical analysis, and reporting of results. We used this evaluation to assess the feasibility of grouping studies into reasonably uniform categories. The most consistently used tests included Brazelton's Neonatal Behavioral Assessment Scale, the neurologic optimality score in the neonatal period, the Bayley Scales of Infant Development at 5-8months of age, and the McCarthy Scales of Children's Abilities in 5-year-olds. Despite administering the same tests at similar ages, the studies were too dissimilar to allow a meaningful quantitative examination of outcomes across cohorts. These analyses indicate that our ability to conduct weight-of-evidence assessments of the epidemiologic literature on neurotoxicants may be limited, even in the presence of multiple studies, if the available study methods, data analysis, and reporting lack comparability.Foram examinados estudos de grupo que avaliaram a relação entre a exposição pré-natal e neonatal aos bifenilos policlorados (PCB e o desenvolvimento neuropsicomotor em crianças a fim de avaliar a viabilidade da realização de uma meta-análise para suporte à tomada de decisão. Nós descrevemos os estudos em termos de exposição, categorizações, análise estatística e elaboração de relatórios de resultados. Nós utilizamos esta avaliação para verificar a viabilidade de agrupar os estudos em categorias razoavelmente uniformes. Os testes mais utilizados foram Brazelton Neonatal Behavioral Assessment Scale, a pontuação de otimalidade neurológica no período neonatal, as Escalas Bayley de Desenvolvimento Infantil de 5 a 8 meses de idade, e as Escalas McCarthy de

  13. Effectiveness of pulmonary rehabilitation in COPD with mild symptoms: a systematic review with meta-analyses

    Directory of Open Access Journals (Sweden)

    Rugbjerg M

    2015-04-01

    Full Text Available Mette Rugbjerg,1 Ulrik Winning Iepsen,1 Karsten Juhl Jørgensen,2 Peter Lange1,3,4 1The Centre of Inflammation and Metabolism and The Centre for Physical Activity Research, Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; 2The Nordic Cochrane Centre, Rigshospitalet, Copenhagen, Denmark; 3Department of Respiratory Medicine, University Hospital Hvidovre, Copenhagen, Denmark; 4Department of Public Health, Section of Social Medicine, University of Copenhagen, Copenhagen, Denmark Purpose: Most guidelines recommend pulmonary rehabilitation (PR for patients with chronic obstructive pulmonary disease (COPD and modified Medical Research Council dyspnea scale (mMRC levels ≥2, but the effectiveness of PR in patients with less advanced disease is not well established. Our aim was to investigate the effects of PR in patients with COPD and mMRC ≤1.Methods: The methodology was developed as a part of evidence-based guideline development and is in accordance with the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE Working Group. We identified randomized controlled trials (RCTs through a systematic, multidatabase literature search and selected RCTs comparing the effects of PR with usual care in patients with COPD and mMRC ≤1. Predefined critical outcomes were health-related quality of life (HRQoL, adverse effects and mortality, while walking distance, maximal exercise capacity, muscle strength, and dropouts were important outcomes. Two authors independently extracted data, assessed trial eligibility and risk of bias, and graded the evidence. Meta-analyses were performed when deemed feasible.Results: Four RCTs (489 participants were included. On the basis of moderate-quality evidence, we found a clinically and statistically significant improvement in short-term HRQoL of 4.2 units (95% confidence interval [CI]: [-4.51 to -3.89] on St George’s Respiratory

  14. Multiplicity of data in trial reports and the reliability of meta-analyses: empirical study

    DEFF Research Database (Denmark)

    Tendal, Britta; Nüesch, Eveline; Higgins, Julian P T;

    2011-01-01

    To examine the extent of multiplicity of data in trial reports and to assess the impact of multiplicity on meta-analysis results.......To examine the extent of multiplicity of data in trial reports and to assess the impact of multiplicity on meta-analysis results....

  15. Lack of association between polymorphisms in the CYP1A2 gene and risk of cancer: evidence from meta-analyses.

    Science.gov (United States)

    Vukovic, Vladimir; Ianuale, Carolina; Leoncini, Emanuele; Pastorino, Roberta; Gualano, Maria Rosaria; Amore, Rosarita; Boccia, Stefania

    2016-02-10

    Polymorphisms in the CYP1A2 genes have the potential to affect the individual capacity to convert pre-carcinogens into carcinogens. With these comprehensive meta-analyses, we aimed to provide a quantitative assessment of the association between the published genetic association studies on CYP1A2 single nucleotide polymorphisms (SNPs) and the risk of cancer. We searched MEDLINE, ISI Web of Science and SCOPUS bibliographic online databases and databases of genome-wide association studies (GWAS). After data extraction, we calculated Odds Ratios (ORs) and 95% confidence intervals (CIs) for the association between the retrieved CYP1A2 SNPs and cancer. Random effect model was used to calculate the pooled ORs. Begg and Egger tests, one-way sensitivity analysis were performed, when appropriate. We conducted stratified analyses by study design, sample size, ethnicity and tumour site. Seventy case-control studies and one GWA study detailing on six different SNPs were included. Among the 71 included studies, 42 were population-based case-control studies, 28 hospital-based case-control studies and one genome-wide association study, including total of 47,413 cancer cases and 58,546 controls. The meta-analysis of 62 studies on rs762551, reported an OR of 1.03 (95% CI, 0.96-1.12) for overall cancer (P for heterogeneity < 0.01; I(2) = 50.4%). When stratifying for tumour site, an OR of 0.84 (95% CI, 0.70-1.01; P for heterogeneity = 0.23, I(2) = 28.5%) was reported for bladder cancer for those homozygous mutant of rs762551. An OR of 0.79 (95% CI, 0.65-0.95; P for heterogeneity = 0.09, I(2) = 58.1%) was obtained for the bladder cancer from the hospital-based studies and on Caucasians. This large meta-analysis suggests no significant effect of the investigated CYP1A2 SNPs on cancer overall risk under various genetic models. However, when stratifying according to the tumour site, our results showed a borderline not significant OR of 0.84 (95% CI, 0.70-1.01) for bladder cancer for those

  16. Incidence of schizophrenia and other psychoses in England, 1950-2009: a systematic review and meta-analyses.

    Directory of Open Access Journals (Sweden)

    James B Kirkbride

    Full Text Available BACKGROUND: We conducted a systematic review of incidence rates in England over a sixty-year period to determine the extent to which rates varied along accepted (age, sex and less-accepted epidemiological gradients (ethnicity, migration and place of birth and upbringing, time. OBJECTIVES: To determine variation in incidence of several psychotic disorders as above. DATA SOURCES: Published and grey literature searches (MEDLINE, PSycINFO, EMBASE, CINAHL, ASSIA, HMIC, and identification of unpublished data through bibliographic searches and author communication. STUDY ELIGIBILITY CRITERIA: Published 1950-2009; conducted wholly or partially in England; original data on incidence of non-organic adult-onset psychosis or one or more factor(s pertaining to incidence. PARTICIPANTS: People, 16-64 years, with first -onset psychosis, including non-affective psychoses, schizophrenia, bipolar disorder, psychotic depression and substance-induced psychosis. STUDY APPRAISAL AND SYNTHESIS METHODS: Title, abstract and full-text review by two independent raters to identify suitable citations. Data were extracted to a standardized extraction form. Descriptive appraisals of variation in rates, including tables and forest plots, and where suitable, random-effects meta-analyses and meta-regressions to test specific hypotheses; rate heterogeneity was assessed by the I²-statistic. RESULTS: 83 citations met inclusion. Pooled incidence of all psychoses (N = 9 was 31.7 per 100,000 person-years (95%CI: 24.6-40.9, 23.2 (95%CI: 18.3-29.5 for non-affective psychoses (N = 8, 15.2 (95%CI: 11.9-19.5 for schizophrenia (N = 15 and 12.4 (95%CI: 9.0-17.1 for affective psychoses (N = 7. This masked rate heterogeneity (I²: 0.54-0.97, possibly explained by socio-environmental factors; our review confirmed (via meta-regression the typical age-sex interaction in psychosis risk, including secondary peak onset in women after 45 years. Rates of most disorders were elevated in

  17. Partial protection against 2009 pandemic influenza A (H1N1) of seasonal influenza vaccination and related regional factors: Updated systematic review and meta-analyses.

    Science.gov (United States)

    Li, Zhi-yuan; Chen, Jin-yan; Zhang, Yan-ling; Fu, Wei-ming

    2015-01-01

    This updated systematic review and meta-analyses aims to systematically evaluate the cross-protection of seasonal influenza vaccines against the 2009 pandemic A (H1N1) influenza infection, and investigate the potential effect of the influenza strains circulating previous to the pandemic on the association between vaccine receipt and pandemic infection. In addition, subgroup analysis was performed based on the study locations and previous circulating influenza viruses. Relevant articles in English and Chinese from 2009 to October 2013 were systematically searched, and 21 eligible studies were included. For case-control studies, an insignificant 20% reduced risk for pandemic influenza infection based on combined national data (OR = 0.80; 95%CI: 0.60, 1.05) was calculated for people receiving seasonal influenza vaccination. However, for RCTs, an insignificant increase in the risk of seasonal influenza vaccines was observed (RR = 1.27; 95% CI: 0.46, 3.53). For the subgroup analysis, a significant 35% cross-protection was observed in the subgroup where influenza A outbreaks were detected before the 2009 pandemic. Moreover, the results indicated that seasonal influenza vaccination may reduce the risk of influenza-like illnesses (ILIs) (RR = 0.91; 95% CI: 0.84, 0.99). Our findings partially support the hypothesis that seasonal vaccines may offer moderate cross-protection for adults against laboratory-confirmed pandemic influenza A (H1N1) infection and ILIs. Further immunological studies are needed to understand the mechanism underlying these findings.

  18. Reporting Quality of Systematic Reviews and Meta-Analyses of Otorhinolaryngologic Articles Based on the PRISMA Statement.

    Directory of Open Access Journals (Sweden)

    Jeroen P M Peters

    Full Text Available Systematic reviews (SRs and meta-analyses (MAs provide the highest possible level of evidence. However, poor conduct or reporting of SRs and MAs may reduce their utility. The PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analyses was developed to help authors report their SRs and MAs adequately.Our objectives were to (1 evaluate the quality of reporting of SRs and MAs and their abstracts in otorhinolaryngologic literature using the PRISMA and PRISMA for Abstracts checklists, respectively, (2 compare the quality of reporting of SRs and MAs published in Ear Nose Throat (ENT journals to the quality of SRs and MAs published in the 'gold standard' Cochrane Database of Systematic Reviews (CDSR, and (3 formulate recommendations to improve reporting of SRs and MAs in ENT journals.On September 3, 2014, we searched the Pubmed database using a combination of filters to retrieve SRs and MAs on otorhinolaryngologic topics published in 2012 and 2013 in the top 5 ENT journals (ISI Web of Knowledge 2013 or CDSR and relevant articles were selected. We assessed how many, and which, PRISMA (for Abstracts items were reported adequately per journal type.We identified large differences in the reporting of individual items between the two journal types with room for improvement. In general, SRs and MAs published in ENT journals (n = 31 reported a median of 54.4% of the PRISMA items adequately, whereas the 49 articles published in the CDSR reported a median of 100.0 adequately (difference statistically significant, p < 0.001. For abstracts, medians of 41.7% for ENT journals and 75.0% for the CDSR were found (p < 0.001.The reporting of SRs and MAs in ENT journals leaves room for improvement and would benefit if the PRISMA Statement were endorsed by these journals.

  19. A critical appraisal of the methodology and quality of evidence of systematic reviews and meta-analyses of traditional Chinese medical nursing interventions: a systematic review of reviews

    Science.gov (United States)

    Jin, Ying-Hui; Wang, Guo-Hao; Sun, Yi-Rong; Li, Qi; Zhao, Chen; Li, Ge; Si, Jin-Hua; Li, Yan; Lu, Cui; Shang, Hong-Cai

    2016-01-01

    Objective To assess the methodology and quality of evidence of systematic reviews and meta-analyses of traditional Chinese medical nursing (TCMN) interventions in Chinese journals. These interventions include acupressure, massage, Tai Chi, Qi Gong, electroacupuncture and use of Chinese herbal medicines—for example, in enemas, foot massage and compressing the umbilicus. Design A systematic literature search for systematic reviews and meta-analyses of TCMN interventions was performed. Review characteristics were extracted. The methodological quality and the quality of the evidence were evaluated using the Assessment of Multiple Systematic Reviews (AMSTAR) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) approaches. Result We included 20 systematic reviews and meta-analyses, and a total of 11 TCMN interventions were assessed in the 20 reviews. The compliance with AMSTAR checklist items ranged from 4.5 to 8 and systematic reviews/meta-analyses were, on average, of medium methodological quality. The quality of the evidence we assessed ranged from very low to moderate; no high-quality evidence was found. The top two causes for downrating confidence in effect estimates among the 31 bodies of evidence assessed were the risk of bias and inconsistency. Conclusions There is room for improvement in the methodological quality of systematic reviews/meta-analyses of TCMN interventions published in Chinese journals. Greater efforts should be devoted to ensuring a more comprehensive search strategy, clearer specification of the interventions of interest in the eligibility criteria and identification of meaningful outcomes for clinicians and patients (consumers). The overall quality of evidence among reviews remains suboptimal, which raise concerns about their roles in influencing clinical practice. Thus, the conclusions in reviews we assessed must be treated with caution and their roles in influencing clinical practice should be limited. A critical

  20. Reporting Bias in Clinical Trials Investigating the Efficacy of Second-Generation Antidepressants in the Treatment of Anxiety Disorders: A Report of 2 Meta-analyses.

    Science.gov (United States)

    Roest, Annelieke M; de Jonge, Peter; Williams, Craig D; de Vries, Ymkje Anna; Schoevers, Robert A; Turner, Erick H

    2015-05-01

    Studies have shown that the scientific literature has overestimated the efficacy of antidepressants for depression, but other indications for these drugs have not been considered. To examine reporting biases in double-blind, placebo-controlled trials on the pharmacologic treatment of anxiety disorders and quantify the extent to which these biases inflate estimates of drug efficacy. We included reviews obtained from the US Food and Drug Administration (FDA) for premarketing trials of 9 second-generation antidepressants in the treatment of anxiety disorders. A systematic search for matching publications (until December 19, 2012) was performed using PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Double data extraction was performed for the FDA reviews and the journal articles. The Hedges g value was calculated as the measure of effect size. Reporting bias was examined and classified as study publication bias, outcome reporting bias, or spin (abstract conclusion not consistent with published results on primary end point). Separate meta-analyses were conducted for the 2 sources, and the effect of publication status on the effect estimates was examined using meta-regression. The findings of 41 of the 57 trials (72%) were positive according to the FDA, but 43 of the 45 published article conclusions (96%) were positive (P antidepressants for anxiety disorders. Although these biases did not significantly inflate estimates of drug efficacy, reporting biases led to significant increases in the number of positive findings in the literature.

  1. 'Jumping to conclusions' data-gathering bias in psychosis and other psychiatric disorders - Two meta-analyses of comparisons between patients and healthy individuals.

    Science.gov (United States)

    So, Suzanne Ho-Wai; Siu, Nicolson Yat-Fan; Wong, Hau-Lam; Chan, Wai; Garety, Philippa Anne

    2016-06-01

    There has been an increase in attention to studying shared mechanisms underlying psychiatric disorders. The 'Jumping to conclusions' (JTC(1)) bias, a tendency to make decisions with certainty based on insufficient information, has been reported in patients with psychosis, and process-based treatment protocols targeting this bias have recently been developed. This review aimed to investigate to what extent the JTC bias, measured by various tasks, is associated with psychotic disorders and other psychiatric disorders using a meta-analytic approach. We examined 6864 articles published between 1990 and 2015, and meta-analysed 46 studies. The first meta-analysis included 40 effect sizes comparing patients with schizophrenia spectrum or other psychotic disorders and healthy controls. There was a hastier data-gathering style in patients with psychosis than healthy individuals, with a moderate aggregated effect size. The second meta-analysis included 18 effect sizes comparing patients with non-psychotic disorders and healthy controls. There was marked heterogeneity in effect sizes and evidence for publication bias. After removal of outliers, the aggregated effect size for JTC was not statistically significant. A planned subgroup analysis showed no significant effect of JTC in depression. Other diagnostic subgroups yielded small non-significant results. Therefore, our findings do not support the suggestion that JTC is a transdiagnostic phenomenon beyond psychosis.

  2. Meta-analyses and Forest plots using a microsoft excel spreadsheet: step-by-step guide focusing on descriptive data analysis

    Directory of Open Access Journals (Sweden)

    Neyeloff Jeruza L

    2012-01-01

    Full Text Available Abstract Background Meta-analyses are necessary to synthesize data obtained from primary research, and in many situations reviews of observational studies are the only available alternative. General purpose statistical packages can meta-analyze data, but usually require external macros or coding. Commercial specialist software is available, but may be expensive and focused in a particular type of primary data. Most available softwares have limitations in dealing with descriptive data, and the graphical display of summary statistics such as incidence and prevalence is unsatisfactory. Analyses can be conducted using Microsoft Excel, but there was no previous guide available. Findings We constructed a step-by-step guide to perform a meta-analysis in a Microsoft Excel spreadsheet, using either fixed-effect or random-effects models. We have also developed a second spreadsheet capable of producing customized forest plots. Conclusions It is possible to conduct a meta-analysis using only Microsoft Excel. More important, to our knowledge this is the first description of a method for producing a statistically adequate but graphically appealing forest plot summarizing descriptive data, using widely available software.

  3. Associations between food and beverage groups and major diet-related chronic diseases: an exhaustive review of pooled/meta-analyses and systematic reviews.

    Science.gov (United States)

    Fardet, Anthony; Boirie, Yves

    2014-12-01

    Associations between food and beverage groups and the risk of diet-related chronic disease (DRCD) have been the subject of intensive research in preventive nutrition. Pooled/meta-analyses and systematic reviews (PMASRs) aim to better characterize these associations. To date, however, there has been no attempt to synthesize all PMASRs that have assessed the relationship between food and beverage groups and DRCDs. The objectives of this review were to aggregate PMASRs to obtain an overview of the associations between food and beverage groups (n = 17) and DRCDs (n = 10) and to establish new directions for future research needs. The present review of 304 PMASRs published between 1950 and 2013 confirmed that plant food groups are more protective than animal food groups against DRCDs. Within plant food groups, grain products are more protective than fruits and vegetables. Among animal food groups, dairy/milk products have a neutral effect on the risk of DRCDs, while red/processed meats tend to increase the risk. Among beverages, tea was the most protective and soft drinks the least protective against DRCDs. For two of the DRCDs examined, sarcopenia and kidney disease, no PMASR was found. Overweight/obesity, type 2 diabetes, and various types of cardiovascular disease and cancer accounted for 289 of the PMASRs. There is a crucial need to further study the associations between food and beverage groups and mental health, skeletal health, digestive diseases, liver diseases, kidney diseases, obesity, and type 2 diabetes.

  4. Meta-analyses and Forest plots using a microsoft excel spreadsheet: step-by-step guide focusing on descriptive data analysis.

    Science.gov (United States)

    Neyeloff, Jeruza L; Fuchs, Sandra C; Moreira, Leila B

    2012-01-20

    Meta-analyses are necessary to synthesize data obtained from primary research, and in many situations reviews of observational studies are the only available alternative. General purpose statistical packages can meta-analyze data, but usually require external macros or coding. Commercial specialist software is available, but may be expensive and focused in a particular type of primary data. Most available softwares have limitations in dealing with descriptive data, and the graphical display of summary statistics such as incidence and prevalence is unsatisfactory. Analyses can be conducted using Microsoft Excel, but there was no previous guide available. We constructed a step-by-step guide to perform a meta-analysis in a Microsoft Excel spreadsheet, using either fixed-effect or random-effects models. We have also developed a second spreadsheet capable of producing customized forest plots. It is possible to conduct a meta-analysis using only Microsoft Excel. More important, to our knowledge this is the first description of a method for producing a statistically adequate but graphically appealing forest plot summarizing descriptive data, using widely available software.

  5. Epidemiology characteristics, reporting characteristics, and methodological quality of systematic reviews and meta-analyses on traditional Chinese medicine nursing interventions published in Chinese journals.

    Science.gov (United States)

    Yang, Min; Jiang, Li; Wang, Aihong; Xu, Guihua

    2017-02-01

    To evaluate the epidemiological characteristics, reporting characteristics, and methodological quality of systematic reviews in the traditional Chinese medicine nursing field published in Chinese journals. The number of systematic reviews in the traditional Chinese medicine nursing field has increased, but their epidemiology, quality, and reporting characteristics have not been assessed completely. We generated an overview of reviews using a narrative approach. Four Chinese databases were searched for systematic reviews from inception to December 2015. The Preferred Reporting Items of Systematic Reviews and Meta-analyses and the Assessment of Multiple Systematic Reviews checklists were adopted to evaluate reporting and methodological quality, respectively. A total of 73 eligible systematic reviews, published from 2005 to 2015, were included. The deficiencies in reporting characteristics mainly lay in the lack of structured abstract or protocol, incomplete reporting of search strategies, study selection, and risk of bias. The deficiencies in methodological quality were reflected in the lack of a priori design and conflict of interest, incomplete literature searches, and assessment of publication bias. The quality of the evaluated reviews was unsatisfactory; attention should be paid to the improvement of reporting and methodological quality in the conduct of systematic reviews.

  6. Peripheral Endothelial (DysFunction, Arterial Stiffness and Carotid Intima-Media Thickness in Patients after Kawasaki Disease: A Systematic Review and Meta-Analyses.

    Directory of Open Access Journals (Sweden)

    Sanne M Dietz

    Full Text Available Kawasaki disease (KD is a systemic pediatric vasculitis. Its main complication is the development of coronary arterial aneurysms (CAA, causing an increased risk for ischemia and myocardial infarction. It is unclear whether KD patients, apart from the presence of CAA, have an increased cardiovascular disease (CVD risk due to the previous systemic vasculitis. The aim of this study was to systematically review and meta-analyse the literature regarding surrogate markers for CVD risk in KD patients.Medline and Embase were searched for articles comparing endothelial dysfunction (flow-mediated dilation, nitroglycerin-mediated dilation and peripheral arterial tonometry, vascular stiffness (stiffness index, pulse wave velocity and carotid intima-media thickness (cIMT between patients and controls. Two investigators assessed the articles for eligibility and evaluated quality.Thirty studies were included. For all outcomes, moderate to high heterogeneity between studies was found. Most studies reported a decreased flow-mediated dilation in the whole KD- and CAA-positive group compared to controls, while data on CAA-negative patients were conflicting. The stiffness index was increased in the majority of studies evaluating the whole KD- and CAA-positive group, but not in most studies on CAA-negative patients. Mean cIMT was neither significantly increased in the whole KD-group nor in the CAA-positive group nor in most studies studying CAA-negative patients. Studies measuring maximum cIMT were conflicting.Literature suggests that surrogate markers for CVD risk in KD patients are increased in CAA-positive but not in CAA-negative patients. This may indicate that CAA-positive patients should be monitored for CVD in later life. The results of this review have to be interpreted with care due to substantial heterogeneity between studies and methodological limitations, as well as the lack of long-term follow-up studies.

  7. Systematic reviews and meta-analyses in coloproctology: interpretation and potential pitfalls

    DEFF Research Database (Denmark)

    Renehan, A.G.; Wille-Jørgensen, Peer

    2008-01-01

    a similar 'anatomy' or format, at an individual class level, there are principles specific to each SR type. Several examples from the coloproctology literature are used as case-studies to illustrate potential pitfalls, and upon re-analysis, often reverse or attenuate the conclusions stated in the original......-making. This educational paper outlines that, from the original prototype based on randomized trials, there are now many other types of SRs including those based on: nonrandomized comparative studies, observational studies, prognostic studies, and studies of diagnostic and screening tools. While each of these has...

  8. The contribution from psychological, social, and organizational work factors to risk of disability retirement: a systematic review with meta-analyses.

    Science.gov (United States)

    Knardahl, Stein; Johannessen, Håkon A; Sterud, Tom; Härmä, Mikko; Rugulies, Reiner; Seitsamo, Jorma; Borg, Vilhelm

    2017-02-08

    Previous studies indicate that psychological, social, and organizational factors at work contribute to health, motivation, absence from work, and functional ability. The objective of the study was to assess the current state of knowledge of the contribution of psychological, social, and organizational factors to disability retirement by a systematic review and meta-analyses. Data sources: A systematic literature search for studies of retirement due to disability in Medline, Embase, and PsychINFO was performed. Reference lists of relevant articles were hand-searched for additional studies. Internal validity was assessed independently by two referees with a detailed checklist for sources of bias. Conclusions were drawn based on studies with acceptable quality. We calculated combined effect estimates by means of averaged associations (Risk ratios) across samples, weighting observed associations by the study's sample size. Thirty-nine studies of accepted quality were found, 37 of which from the Nordic countries. There was moderate evidence for the role of low control (supported by weighted average RR = 1.40; 95% CI = 1.21-1.61) and moderate evidence for the combination of high demands and low control (although weighted average was RR = 1.45; 95% CI = 0.96-2.19) as predictors of disability retirement. There were no major systematic differences in findings between the highest rated and the lowest rated studies that passed the criterion for adequate quality. There was limited evidence for downsizing, organizational change, lack of employee development and supplementary training, repetitive work tasks, effort-reward imbalance to increase risk of disability pension. Very limited evidence was found for job demands, evening or night work, and low social support from ones superior. Psychological and organizational factors at work contribute to disability retirement with the most robust evidence for the role of work control. We recommend the measurement of

  9. Interpreting discordant indirect and multiple treatment comparison meta-analyses: an evaluation of direct acting antivirals for chronic hepatitis C infection

    Directory of Open Access Journals (Sweden)

    Druyts E

    2013-06-01

    Full Text Available Eric Druyts,1 Kristian Thorlund,2,3 Samantha Humphreys,4 Michaela Lion,4 Curtis L Cooper,5 Edward J Mills1,31Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada; 2Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada; 3Stanford Prevention Research Centre, Department of Medicine, Stanford University, Palo Alto, CA, USA; 4Merck Sharp and Dohme Ltd, UK; 5Division of Infectious Diseases, Department of Medicine, The Ottawa Hospital, University of Ottawa, Ottawa, Ontario, CanadaAbstract: Indirect treatment comparison (ITC and multiple treatment comparison (MTC meta-analyses are increasingly being used to estimate the comparative effectiveness of interventions when head-to-head data do not exist. ITC meta-analyses can be conducted using simple methodology to compare two interventions. MTC meta-analyses can be conducted using more complex methodology, often employing Bayesian approaches, to compare multiple interventions. As the number of ITC and MTC meta-analyses increase, it is common to find multiple analyses evaluating the same interventions in similar therapeutic areas. Depending on the choice of the methodological approach, the conclusions about relative treatment efficacy may differ. Such situations create uncertainty for decision makers. An illustration of this is provided by four ITC and MTC meta-analyses assessing the efficacy of boceprevir and telaprevir for chronic hepatitis C virus infection. This paper examines why these evaluations provide discordant results by examining specific methodological issues that can strengthen or weaken inferences.Keywords: indirect treatment comparison, multiple treatment comparison, meta-analysis, hepatitis C virus

  10. A Microsoft-Excel-based tool for running and critically appraising network meta-analyses--an overview and application of NetMetaXL.

    Science.gov (United States)

    Brown, Stephen; Hutton, Brian; Clifford, Tammy; Coyle, Doug; Grima, Daniel; Wells, George; Cameron, Chris

    2014-09-29

    The use of network meta-analysis has increased dramatically in recent years. WinBUGS, a freely available Bayesian software package, has been the most widely used software package to conduct network meta-analyses. However, the learning curve for WinBUGS can be daunting, especially for new users. Furthermore, critical appraisal of network meta-analyses conducted in WinBUGS can be challenging given its limited data manipulation capabilities and the fact that generation of graphical output from network meta-analyses often relies on different software packages than the analyses themselves. We developed a freely available Microsoft-Excel-based tool called NetMetaXL, programmed in Visual Basic for Applications, which provides an interface for conducting a Bayesian network meta-analysis using WinBUGS from within Microsoft Excel. . This tool allows the user to easily prepare and enter data, set model assumptions, and run the network meta-analysis, with results being automatically displayed in an Excel spreadsheet. It also contains macros that use NetMetaXL's interface to generate evidence network diagrams, forest plots, league tables of pairwise comparisons, probability plots (rankograms), and inconsistency plots within Microsoft Excel. All figures generated are publication quality, thereby increasing the efficiency of knowledge transfer and manuscript preparation. We demonstrate the application of NetMetaXL using data from a network meta-analysis published previously which compares combined resynchronization and implantable defibrillator therapy in left ventricular dysfunction. We replicate results from the previous publication while demonstrating result summaries generated by the software. Use of the freely available NetMetaXL successfully demonstrated its ability to make running network meta-analyses more accessible to novice WinBUGS users by allowing analyses to be conducted entirely within Microsoft Excel. NetMetaXL also allows for more efficient and transparent

  11. Reporting and Methodological Quality of Systematic Reviews and Meta-Analyses in Nursing Field in China%国内护理领域系统评价/Meta分析的方法学与报告质量评价

    Institute of Scientific and Technical Information of China (English)

    靳英辉; 马恩婷; 花巍; 窦昊颖

    2012-01-01

    -Based Medicine. The deficiencies of methodological quality mainly contained literature search, heterogeneity handling, recognition and assessment of publication bias. In addition, the deficiencies of reporting characteristics were reflected on incomplete reporting of literature search, quality assessment, risk of bias and results (some studies lacked forest plot, estimated value of pooled results, 95%CI or heterogeneity). Conclusion As a whole, the included reviews and meta-analyses have more or less flaws with regard to the quality of reporting and methodology based on the PRISMA and AMSTAR checklists. Focusing on the improvement of reporting and methodological quality of systematic review or meta-analysis in nursing field in China is urgently needed in order to increase the value of these studies.

  12. Systematic review and meta-analyses of risk factors for childhood overweight identifiable during infancy

    OpenAIRE

    2012-01-01

    Objective To determine risk factors for childhood overweight that can be identified during the first year of life to facilitate early identification and targeted intervention. Design Systematic review and meta-analysis. Search strategy Electronic database search of MEDLINE, EMBASE, PubMed and CAB Abstracts. Eligibility criteria Prospective observational studies following up children from birth for at least 2 years. Results Thirty prospective studies were identified. Significant and strong ind...

  13. Cervical Cancer Genetic Susceptibility: A Systematic Review and Meta-Analyses of Recent Evidence.

    Directory of Open Access Journals (Sweden)

    Gabriela A Martínez-Nava

    Full Text Available Cervical cancer (CC has one of the highest mortality rates among women worldwide. Several efforts have been made to identify the genetic susceptibility factors underlying CC development. However, only a few polymorphisms have shown consistency among studies.We conducted a systematic review of all recent case-control studies focused on the evaluation of single nucleotide polymorphisms (SNPs and CC risk, stringently following the "PRISMA" statement recommendations. The MEDLINE data base was used for the search. A total of 100 case-control studies were included in the meta-analysis. Polymorphisms that had more than two reports were meta-analyzed by fixed or random models according to the heterogeneity presented among studies.We found significant negative association between the dominant inheritance model of p21 rs1801270 polymorphism (C/A+A/A and CC (pooled OR = 0.76; 95%CI: 0.63-0.91; p<0.01. We also found a negative association with the rs2048718 BRIP1 polymorphism dominant inheritance model (T/C+C/C and CC (pooled OR = 0.83; 95%CI: 0.70-0.98; p = 0.03, as well as with the rs11079454 BRIP1 polymorphism recessive inheritance model and CC (pooled OR = 0.79; 95%CI: 0.63-0.99; p = 0.04. Interestingly, we observed a strong tendency of the meta-analyzed studies to be of Asiatic origin (67%. We also found a significant low representation of African populations (4%.Our results provide evidence of the negative association of p21 rs1801270 polymorphism, as well as BRIP1 rs2048718 and rs11079454 polymorphisms, with CC risk. This study suggests the urgent need for more replication studies focused on GWAS identified CC susceptibility variants, in order to reveal the most informative genetic susceptibility markers for CC across different populations.

  14. Cervical Cancer Genetic Susceptibility: A Systematic Review and Meta-Analyses of Recent Evidence

    Science.gov (United States)

    Martínez-Nava, Gabriela A.; Fernández-Niño, Julián A.; Madrid-Marina, Vicente; Torres-Poveda, Kirvis

    2016-01-01

    Introduction Cervical cancer (CC) has one of the highest mortality rates among women worldwide. Several efforts have been made to identify the genetic susceptibility factors underlying CC development. However, only a few polymorphisms have shown consistency among studies. Materials and Methods We conducted a systematic review of all recent case-control studies focused on the evaluation of single nucleotide polymorphisms (SNPs) and CC risk, stringently following the “PRISMA” statement recommendations. The MEDLINE data base was used for the search. A total of 100 case-control studies were included in the meta-analysis. Polymorphisms that had more than two reports were meta-analyzed by fixed or random models according to the heterogeneity presented among studies. Results We found significant negative association between the dominant inheritance model of p21 rs1801270 polymorphism (C/A+A/A) and CC (pooled OR = 0.76; 95%CI: 0.63–0.91; p<0.01). We also found a negative association with the rs2048718 BRIP1 polymorphism dominant inheritance model (T/C+C/C) and CC (pooled OR = 0.83; 95%CI: 0.70–0.98; p = 0.03), as well as with the rs11079454 BRIP1 polymorphism recessive inheritance model and CC (pooled OR = 0.79; 95%CI: 0.63–0.99; p = 0.04). Interestingly, we observed a strong tendency of the meta-analyzed studies to be of Asiatic origin (67%). We also found a significant low representation of African populations (4%). Conclusions Our results provide evidence of the negative association of p21 rs1801270 polymorphism, as well as BRIP1 rs2048718 and rs11079454 polymorphisms, with CC risk. This study suggests the urgent need for more replication studies focused on GWAS identified CC susceptibility variants, in order to reveal the most informative genetic susceptibility markers for CC across different populations. PMID:27415837

  15. 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

  16. Auto-titrating versus fixed continuous positive airway pressure for the treatment of obstructive sleep apnea: a systematic review with meta-analyses

    Directory of Open Access Journals (Sweden)

    Ip Stanley

    2012-03-01

    Full Text Available Abstract Background Obstructive sleep apnea is a relatively common disorder that can lead to lost productivity and cardiovascular disease. The form of positive airway treatment that should be offered is unclear. Methods MEDLINE and the Cochrane Central Trials registry were searched for English language randomized controlled trials comparing auto-titrating positive airway pressure (APAP with continuous positive airway pressure (CPAP in adults with obstructive sleep apnea (inception through 9/2010. Six researchers extracted information on study design, potential bias, patient characteristics, interventions and outcomes. Data for each study were extracted by one reviewer and confirmed by another. Random effects model meta-analyses were performed for selected outcomes. Results Twenty-four randomized controlled trials met the inclusion criteria. In individual studies, APAP and fixed CPAP resulted in similar changes from baseline in the apnea-hypopnea index, most other sleep study measures and quality of life. By meta-analysis, APAP improved compliance by 11 minutes per night (95% CI, 3 to 19 minutes and reduced sleepiness as measured by the Epworth Sleepiness Scale by 0.5 points (95% CI, 0.8 to 0.2 point reduction compared with fixed CPAP. Fixed CPAP improved minimum oxygen saturation by 1.3% more than APAP (95% CI, 0.4 to 2.2%. Studies had relatively short follow-up and generally excluded patients with significant comorbidities. No study reported on objective clinical outcomes. Conclusions Statistically significant differences were found but clinical importance is unclear. Because the treatment effects are similar between APAP and CPAP, the therapy of choice may depend on other factors such as patient preference, specific reasons for non-compliance and cost.

  17. Publication Bias in Meta-Analyses of the Efficacy of Psychotherapeutic Interventions for Depression

    Science.gov (United States)

    Niemeyer, Helen; Musch, Jochen; Pietrowsky, Reinhard

    2013-01-01

    Objective: The aim of this study was to assess whether systematic reviews investigating psychotherapeutic interventions for depression are affected by publication bias. Only homogeneous data sets were included, as heterogeneous data sets can distort statistical tests of publication bias. Method: We applied Begg and Mazumdar's adjusted rank…

  18. Childhood Attention-Deficit/Hyperactivity Disorder and Future Substance Use Disorders: Comparative Meta-Analyses

    Science.gov (United States)

    Charach, Alice; Yeung, Emanuela; Climans, Troy; Lillie, Erin

    2011-01-01

    Objective: In recent years cohort studies have examined childhood attention-deficit/hyperactivity disorder (ADHD) as a risk factor for substance use disorders (SUDs) in adolescence and young adulthood. The long-term risk is estimated for development of alcohol, cannabis, combined alcohol and psychoactive SUDs, combined SUDs (nonalcohol), and…

  19. Evolution of heterogeneity (I2) estimates and their 95% confidence intervals in large meta-analyses

    DEFF Research Database (Denmark)

    Thorlund, Kristian; Imberger, Georgina; Johnston, Bradley C

    2012-01-01

    by sampling error. Recent studies have raised concerns about the reliability of I(2) estimates, due to their dependence on the precision of included trials and time-dependent biases. Authors have also advocated use of 95% confidence intervals (CIs) to express the uncertainty associated with I(2) estimates...

  20. Psychologische behandeling van depressie: een systematisch overzicht van meta-analyses,

    NARCIS (Netherlands)

    Cuijpers, P.; Dekker, J.J.M.

    2005-01-01

    Doel. Een overzicht geven van de meta-analysen naar de effectiviteit van psychologische behandelingen van patiënten met een depressieve stoornis. Opzet. Systematische review. Methode. Gezocht werd in Pubmed, Psycinfo en DARE, in eerdere reviews en in referentielijsten van geïncludeerde studies. Incl

  1. Genome-wide meta-analyses of smoking behaviors in African Americans.

    Science.gov (United States)

    David, S P; Hamidovic, A; Chen, G K; Bergen, A W; Wessel, J; Kasberger, J L; Brown, W M; Petruzella, S; Thacker, E L; Kim, Y; Nalls, M A; Tranah, G J; Sung, Y J; Ambrosone, C B; Arnett, D; Bandera, E V; Becker, D M; Becker, L; Berndt, S I; Bernstein, L; Blot, W J; Broeckel, U; Buxbaum, S G; Caporaso, N; Casey, G; Chanock, S J; Deming, S L; Diver, W R; Eaton, C B; Evans, D S; Evans, M K; Fornage, M; Franceschini, N; Harris, T B; Henderson, B E; Hernandez, D G; Hitsman, B; Hu, J J; Hunt, S C; Ingles, S A; John, E M; Kittles, R; Kolb, S; Kolonel, L N; Le Marchand, L; Liu, Y; Lohman, K K; McKnight, B; Millikan, R C; Murphy, A; Neslund-Dudas, C; Nyante, S; Press, M; Psaty, B M; Rao, D C; Redline, S; Rodriguez-Gil, J L; Rybicki, B A; Signorello, L B; Singleton, A B; Smoller, J; Snively, B; Spring, B; Stanford, J L; Strom, S S; Swan, G E; Taylor, K D; Thun, M J; Wilson, A F; Witte, J S; Yamamura, Y; Yanek, L R; Yu, K; Zheng, W; Ziegler, R G; Zonderman, A B; Jorgenson, E; Haiman, C A; Furberg, H

    2012-05-22

    The identification and exploration of genetic loci that influence smoking behaviors have been conducted primarily in populations of the European ancestry. Here we report results of the first genome-wide association study meta-analysis of smoking behavior in African Americans in the Study of Tobacco in Minority Populations Genetics Consortium (n = 32,389). We identified one non-coding single-nucleotide polymorphism (SNP; rs2036527[A]) on chromosome 15q25.1 associated with smoking quantity (cigarettes per day), which exceeded genome-wide significance (β = 0.040, s.e. = 0.007, P = 1.84 × 10(-8)). This variant is present in the 5'-distal enhancer region of the CHRNA5 gene and defines the primary index signal reported in studies of the European ancestry. No other SNP reached genome-wide significance for smoking initiation (SI, ever vs never smoking), age of SI, or smoking cessation (SC, former vs current smoking). Informative associations that approached genome-wide significance included three modestly correlated variants, at 15q25.1 within PSMA4, CHRNA5 and CHRNA3 for smoking quantity, which are associated with a second signal previously reported in studies in European ancestry populations, and a signal represented by three SNPs in the SPOCK2 gene on chr10q22.1. The association at 15q25.1 confirms this region as an important susceptibility locus for smoking quantity in men and women of African ancestry. Larger studies will be needed to validate the suggestive loci that did not reach genome-wide significance and further elucidate the contribution of genetic variation to disparities in cigarette consumption, SC and smoking-attributable disease between African Americans and European Americans.

  2. Corticosteroids in the adjunctive therapy of community-acquired pneumonia: an appraisal of recent meta-analyses of clinical trials.

    Science.gov (United States)

    Feldman, Charles; Anderson, Ronald

    2016-03-01

    Improving the outcome of patients with community-acquired pneumonia (CAP) is an ongoing challenge, even in the setting of significant advances in antimicrobial chemotherapy and critical care. Recognition of the underlying involvement of inflammation-mediated organ dysfunction as a determinant of adverse outcomes in CAP has aroused intense interest in the protective potential of adjunctive anti-inflammatory therapies in CAP, particularly the role of corticosteroids (CS). This is the primary topic of the current review which is focused on an evaluation of the latest meta-analyses encompassing both recent and earlier clinical trials, with particular emphasis on the stringent meta-analysis undertaken by Siemieniuk and colleagues (Ann Intern Med 2015;163:519-528). The review highlights the findings and recommendations of these and related published commentaries/critiques, while providing a brief description of those sub-groups of patients who seemingly stand to benefit most from CS therapy. This is preceded by an overview of the mechanisms of the anti-inflammatory activities of CS, the interactions of these agents with macrolide antibiotics, and the potential benefits and risks of short-term administration of CS, concluding with a succinct appraisal of priority issues for ongoing and future research.

  3. Molecular evidence for the inverse comorbidity between central nervous system disorders and cancers detected by transcriptomic meta-analyses.

    Directory of Open Access Journals (Sweden)

    Kristina Ibáñez

    2014-02-01

    Full Text Available There is epidemiological evidence that patients with certain Central Nervous System (CNS disorders have a lower than expected probability of developing some types of Cancer. We tested here the hypothesis that this inverse comorbidity is driven by molecular processes common to CNS disorders and Cancers, and that are deregulated in opposite directions. We conducted transcriptomic meta-analyses of three CNS disorders (Alzheimer's disease, Parkinson's disease and Schizophrenia and three Cancer types (Lung, Prostate, Colorectal previously described with inverse comorbidities. A significant overlap was observed between the genes upregulated in CNS disorders and downregulated in Cancers, as well as between the genes downregulated in CNS disorders and upregulated in Cancers. We also observed expression deregulations in opposite directions at the level of pathways. Our analysis points to specific genes and pathways, the upregulation of which could increase the incidence of CNS disorders and simultaneously lower the risk of developing Cancer, while the downregulation of another set of genes and pathways could contribute to a decrease in the incidence of CNS disorders while increasing the Cancer risk. These results reinforce the previously proposed involvement of the PIN1 gene, Wnt and P53 pathways, and reveal potential new candidates, in particular related with protein degradation processes.

  4. Meta-analyses on behavioral interventions to reduce the risk of transmission of HIV.

    Science.gov (United States)

    Vergidis, Paschalis I; Falagas, Matthew E

    2009-06-01

    Different behavioral interventions have found to be efficacious in reducing high-risk sexual activity. Interventions have been evaluated in both original research and meta-analytic reviews. Most of the studies have shown that interventions are efficacious among different study populations. In adolescents, both in- and out-of-the classroom interventions showed a decrease in the risk of unprotected sex. In African Americans, greater efficacy was found for interventions including peer education. For Latinos, effect was larger in interventions with segmentation in the same gender. Geographic and social isolation are barriers in approaching MSM. For IDUs, interventions provided within a treatment program have an impact on risk reduction above that produced by drug treatment alone. Finally, people diagnosed with HIV tend to reduce their sexual risk behavior. However, adherence to safe sex practices for life can be challenging. Relentless efforts for implementation of behavioral interventions to decrease high-risk behavior are necessary to decrease HIV transmission.

  5. Meta-analyses of the determinants and outcomes of belief in climate change

    Science.gov (United States)

    Hornsey, Matthew J.; Harris, Emily A.; Bain, Paul G.; Fielding, Kelly S.

    2016-06-01

    Recent growth in the number of studies examining belief in climate change is a positive development, but presents an ironic challenge in that it can be difficult for academics, practitioners and policy makers to keep pace. As a response to this challenge, we report on a meta-analysis of the correlates of belief in climate change. Twenty-seven variables were examined by synthesizing 25 polls and 171 academic studies across 56 nations. Two broad conclusions emerged. First, many intuitively appealing variables (such as education, sex, subjective knowledge, and experience of extreme weather events) were overshadowed in predictive power by values, ideologies, worldviews and political orientation. Second, climate change beliefs have only a small to moderate effect on the extent to which people are willing to act in climate-friendly ways. Implications for converting sceptics to the climate change cause--and for converting believers’ intentions into action--are discussed.

  6. Effect of Exercise on Inflammatory Profile of Older Persons: Systematic Review and Meta-Analyses.

    Science.gov (United States)

    Monteiro Junior, Renato Sobral; de Tarso Maciel-Pinheiro, Paulo; da Matta M Portugal, Eduardo; da Silva Figueiredo, Luiz Felipe; Terra, Rodrigo; Carneiro, Lara S F; Rodrigues, Vinicius Dias; Nascimento, Osvaldo José Moreira; Deslandes, Andrea Camaz; Laks, Jerson

    2017-08-03

    Inflammatory cytokines and acute phase proteins increase with ageing, promoting a chronic low-grade inflammation. Studies have shown a positive effect of exercise on inflammatory markers in older persons. Interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and C-reactive protein (CRP) are the main biomarkers investigated. However, it is unclear if exercise could decrease all these biomarkers. The aim was to analyze the effect of chronic exercise on IL-6, TNF-α and CRP levels in older persons. PRISMA Guidelines were adopted. Original articles that investigated the effect of chronic exercise on inflammatory profile of the elderly were eligible for this review. Database was used to search data on PubMed, PEDro, EBSCO and BioMed Central. Three reviewers evaluated each publication for reducing bias. Data about IL-6, TNF-α and CRP were collected and analyzed. A standardized mean difference (SMD) based on estimated Pooled Effect Size was calculated considering heterogeneity index (I2) and random effect. Seventy-six studies were retrieved from databases and eight of them were analyzed. IL-6 and CRP levels decreased after chronic exercise (overall effect p<0.05). Regular exercise decreases IL-6 and CRP levels in older persons. Effect of exercise on TNF-α remain unclear.

  7. An Overview of Meta-Analyses of Danhong Injection for Unstable Angina

    Directory of Open Access Journals (Sweden)

    Xiaoxia Zhang

    2015-01-01

    Full Text Available Objective. To systematically collect evidence and evaluate the effects of Danhong injection (DHI for unstable angina (UA. Methods. A comprehensive search was conducted in seven electronic databases up to January 2015. The methodological and reporting quality of included studies was assessed by using AMSTAR and PRISMA. Result. Five articles were included. The conclusions suggest that DHI plus conventional medicine treatment was effective for UA pectoris treatment, could alleviate symptoms of angina and ameliorate electrocardiograms. Flaws of the original studies and systematic reviews weaken the strength of evidence. Limitations of the methodology quality include performing an incomprehensive literature search, lacking detailed characteristics, ignoring clinical heterogeneity, and not assessing publication bias and other forms of bias. The flaws of reporting systematic reviews included the following: not providing a structured summary, no standardized search strategy. For the pooled findings, researchers took statistical heterogeneity into consideration, but clinical and methodology heterogeneity were ignored. Conclusion. DHI plus conventional medicine treatment generally appears to be effective for UA treatment. However, the evidence is not hard enough due to methodological flaws in original clinical trials and systematic reviews. Furthermore, rigorous designed randomized controlled trials are also needed. The methodology and reporting quality of systematic reviews should be improved.

  8. Accuracy of Cuff-Measured Blood Pressure: Systematic Reviews and Meta-Analyses

    DEFF Research Database (Denmark)

    Picone, Dean S; Schultz, Martin G; Otahal, Petr

    2017-01-01

    % CI: -1.5 to 2.1 mm Hg; p = 0.77) but poor agreement (mean absolute difference 8.0 mm Hg; 95% CI: 7.1 to 8.9 mm Hg). Concordance between BP classification using the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure cuff BP (normal......BACKGROUND: Hypertension (HTN) is the single greatest cardiovascular risk factor worldwide. HTN management is usually guided by brachial cuff blood pressure (BP), but questions have been raised regarding accuracy. OBJECTIVES: This comprehensive analysis determined the accuracy of cuff BP...... studies with 3,073 participants were included. Intra-arterial brachial systolic blood pressure (SBP) was higher than aortic values (8.0 mm Hg; 95% confidence interval [CI]: 5.9 to 10.1 mm Hg; p

  9. Nutraceuticals and Blood Pressure Control: Results from Clinical Trials and Meta-Analyses.

    Science.gov (United States)

    Cicero, Arrigo F G; Colletti, Alessandro

    2015-09-01

    Beyond the well-known effects on blood pressure (BP) of the dietary approaches to stop hypertension (DASH) and the Mediterranean diets, a large number of studies has investigated the possible BP lowering effect of different dietary supplements and nutraceuticals, the most part of them being antioxidant agents with a high tolerability and safety profile. In particular relatively large body of evidence support the use of potassium, L-arginine, vitamin C, cocoa flavonoids, beetroot juice, coenzyme Q10, controlled-release melatonin, and aged garlic extract. However there is a need for data about the long-term safety of a large part of the above discussed products. Moreover further clinical research is advisable to identify between the available active nutraceuticals those with the best cost-effectiveness and risk-benefit ratio for a large use in general population with low-added cardiovascular risk related to uncomplicated hypertension.

  10. Meta-Analyses of Developing Brain Function in High-Risk and Emerged Bipolar Disorder

    Directory of Open Access Journals (Sweden)

    Moon-Soo eLee

    2014-11-01

    Full Text Available Objectives: Identifying early markers of brain function among those at high risk for pediatric bipolar disorder (PBD could serve as a screening measure when children and adolescents present with sub-syndromal clinical symptoms prior to the conversion to bipolar disorder. Studies on the offspring of patients with bipolar disorder who are genetically at high risk (HR have each been limited in establishing a biomarker, while an analytic review in summarizing the findings offers an improvised opportunity towards that goal. Methods: An activation likelihood estimation meta-analysis of mixed cognitive and emotional activities using the GingerALE software from the BrainMap Project was completed. The meta-analysis of all fMRI studies contained a total of 29 reports and included PBD, HR and typically developing (TD groups.Results: The HR group showed significantly greater activation relative to the TD group in the right DLPFC-insular-parietal-cerebellar regions. Similarly, the HR group exhibited greater activity in the right DLPFC and insula as well as the left cerebellum compared to patients with PBD. Patients with PBD, relative to TD, showed greater activation in regions of the right amygdala, parahippocampal gyrus, medial PFC, left ventral striatum, and cerebellum and lower activation in the right VLPFC and the DLPFC.Conclusions: The HR population showed increased activity, presumably indicating greater compensatory deployment, in relation to both the TD and the PBD, in the key cognition and emotion processing regions, such as the DLPFC, insula and parietal cortex. In contrast, patients with PBD, relative to HR and TD, showed decreased activity, which could indicate a decreased effort in multiple PFC regions in addition to widespread subcortical abnormalities, which are suggestive of a more entrenched disease process.

  11. Meta-analyses of developing brain function in high-risk and emerged bipolar disorder.

    Science.gov (United States)

    Lee, Moon-Soo; Anumagalla, Purnima; Talluri, Prasanth; Pavuluri, Mani N

    2014-01-01

    Identifying early markers of brain function among those at high risk (HR) for pediatric bipolar disorder (PBD) could serve as a screening measure when children and adolescents present with subsyndromal clinical symptoms prior to the conversion to bipolar disorder. Studies on the offspring of patients with bipolar disorder who are genetically at HR have each been limited in establishing a biomarker, while an analytic review in summarizing the findings offers an improvised opportunity toward that goal. An activation likelihood estimation (ALE) meta-analysis of mixed cognitive and emotional activities using the GingerALE software from the BrainMap Project was completed. The meta-analysis of all fMRI studies contained a total of 29 reports and included PBD, HR, and typically developing (TD) groups. The HR group showed significantly greater activation relative to the TD group in the right DLPFC-insular-parietal-cerebellar regions. Similarly, the HR group exhibited greater activity in the right DLPFC and insula as well as the left cerebellum compared to patients with PBD. Patients with PBD, relative to TD, showed greater activation in regions of the right amygdala, parahippocampal gyrus, medial PFC, left ventral striatum, and cerebellum and lower activation in the right VLPFC and the DLPFC. The HR population showed increased activity, presumably indicating greater compensatory deployment, in relation to both the TD and the PBD, in the key cognition and emotion-processing regions, such as the DLPFC, insula, and parietal cortex. In contrast, patients with PBD, relative to HR and TD, showed decreased activity, which could indicate a decreased effort in multiple PFC regions in addition to widespread subcortical abnormalities, which are suggestive of a more entrenched disease process.

  12. Meta-analyses of the effects of major global change drivers on soil respiration across China

    Science.gov (United States)

    Feng, Jiguang; Wang, Jingsheng; Ding, Lubin; Yao, Pingping; Qiao, Mengping; Yao, Shuaichen

    2017-02-01

    Soil respiration (Rs) is affected largely by major global change drivers, global meta-analysis studies have synthesized the available information to determine how Rs responds to these drivers. However, little is known about the effects of these drivers on Rs across China. Here, we conducted a meta-analysis to synthesize 80 studies published in the literature with 301 paired comparisons to quantify the responses of Rs to simulated warming, nitrogen addition, precipitation increase and acid rain across Chinese terrestrial ecosystem. Results showed that global change drivers significantly changed Rs across Chinese ecosystems. Warming, nitrogen addition, and precipitation increase significantly increased Rs by 9.08%, 5.21%, 31.68%, respectively, while simulated acid rain decreased Rs by 7.06%. The responses of Rs to warming, nitrogen addition, and precipitation increase are similar in both direction and magnitude to those reported in global syntheses, except for higher response ratio under precipitation increase in China. In addition, the responses of Rs were different among ecosystem types, and among experimental treatments. Warming significantly increased Rs in croplands but did not change in forests and grasslands. The effect magnitude of N addition on Rs in grasslands and croplands was much higher than those in other ecosystems. In general, precipitation increase stimulated Rs in different ecosystems, and its effect magnitudes increased with changed precipitation levels. However, acid rain inhibited Rs in different biomes and intensities of acid rain. Our findings contribute to better understanding of how Rs will change under global change, and provide important parameters for carbon cycle model at the regional scale.

  13. Evidence from enzymatic and meta-analyses does not support a direct association between USP26 gene variants and male infertility.

    Science.gov (United States)

    Zhang, W; Liu, T; Mi, Y-J; Yue, L-D; Wang, J-M; Liu, D-W; Yan, J; Tian, Q B

    2015-03-01

    Do men who carry mutations in USP26 have an increased risk of infertility? The association between mutations in USP26 gene and male infertility has been studied intensively. However, the results from different groups are controversial. In particular, biological function of the mutant proteins remains to be elucidated. In this study, we conducted a USP cleavage assay and a meta-analysis of the published literature (up to 31 May 2013) to evaluate the impact of five frequent mutations (NM_031907.1: c.363_364insACA, c.494T>C, c.1423C>T, c.1090C>T, c.1737G>A) on enzymatic activity of the USP26 and to assess the strength of the association between those mutations and male infertility. The USP cleavage assay showed that those mutations do not affect USP26 enzymatic activity. Moreover, the results of meta-analysis of ten case-control studies (in total 1716 patients and 2597 controls) revealed no significant association (P > 0.05) between USP26 mutations and male infertility. The pooled ORs were 1.58 (95% CI: 0.81, 3.10) for cluster mutations (c.363_364insACA, c.494T>C, c.1423C>T), 1.60 (95% CI: 0.93, 2.74) for c.1090 C>T and 2.64 (95% CI: 0.97, 7.20) for c.1737 G>A. Evidence from both enzymatic and meta-analyses does not support a direct association between USP26 variants and male infertility. Further research is necessary to study the biological function of USP26, which may provide clues as to the regulation of androgen receptor signalling. © 2015 American Society of Andrology and European Academy of Andrology.

  14. Acceptance and Commitment Therapy (ACT) for Chronic Pain: A Systematic Review and Meta-Analyses.

    Science.gov (United States)

    Hughes, Laura S; Clark, Jodi; Colclough, Janette A; Dale, Elizabeth; McMillan, Dean

    2017-06-01

    Chronic pain places a burden on individuals and the economy. Although there is evidence for the effectiveness of cognitive-behavior therapy, it is recognized that the effects are limited. Acceptance and Commitment Therapy (ACT), which aims to increase valued action in the presence of pain, has been suggested as an alternative approach. The objective of this review was to determine the clinical effectiveness of ACT for chronic pain in adults when compared with control conditions and other active treatments. The searches of this systematic review were conducted in the Cochrane library, MEDLINE, EMBASE, CINAHL Plus (EBSCO), and PsycINFO. Grey literature, reference list, and reverse citation searches were also completed. Eleven trials were included. ACT was favored over controls (no alternative intervention or treatment as usual). Significant, medium to large effect sizes were found for measures of pain acceptance and psychological flexibility, which are typically considered processes of ACT. Significant small to medium effect sizes were found for measures of functioning, anxiety, and depression. Measures of pain intensity and quality of life were not significantly different than zero. Generally effect sizes were smaller at follow-up. ACT was more clinically effective than controls on a number of outcomes. It is possible that methodological limitations, some of which are common to psychological trials, may have led to overestimated effects. Only a few studies compared ACT to active treatments and while the evidence is promising for ACT in the treatment of chronic pain, further methodologically robust trials are required.

  15. Three key regions for supervisory attentional control: Evidence from neuroimaging meta-analyses

    Science.gov (United States)

    Cieslik, Edna C.; Mueller, Veronika I.; Eickhoff, Claudia R.; Langner, Robert; Eickhoff, Simon B.

    2014-01-01

    The supervisory attentional system has been proposed to mediate non-routine, goal-oriented behaviour by guiding the selection and maintenance of the goal-relevant task schema. Here, we aimed to delineate the brain regions that mediate these high-level control processes via neuroimaging meta-analysis. In particular, we investigated the core neural correlates of a wide range of tasks requiring supervisory control for the suppression of a routine action in favour of another, non-routine one. Our sample comprised n = 173 experiments employing go/no-go, stop-signal, Stroop or spatial interference tasks. Consistent convergence across all four paradigm classes was restricted to right anterior insula and inferior frontal junction, with anterior midcingulate cortex and pre-supplementary motor area being consistently involved in all but the go/no-go task. Taken together with lesion studies in patients, our findings suggest that the controlled activation and maintenance of adequate task schemata relies, across paradigms, on a right-dominant midcingulo-insular-inferior frontal core network. This also implies that the role of other prefrontal and parietal regions may be less domain-general than previously thought. PMID:25446951

  16. [Procedures for performing meta-analyses of the accuracy of tools for binary classification].

    Science.gov (United States)

    Botella, Juan; Huang, Huiling

    2012-02-01

    The assessment of accuracy in binary classification tools must take into account two non-independent rates: true positives and false positives. A variety of indices have been proposed. They have been estimated for tests employed for early detection or screening purposes. We summarize and review the main methods proposed for performing a meta-analysis that assesses the accuracy of this type of tools. They are applied to the results from 14 studies that report estimates of the accuracy of the AUDIT. The method of direct aggregation does not allow the use of meta-analytic procedures; the separate estimation of sensitivity and specificity does not acknowledge that they are not independent; the SROC method treats accuracy and threshold as fixed effects and has limitations to deal with the potential role of covariates. The Normal Bivariate (NB) model and the Hierarchical Summary ROC (HSROC) model are statistically rigorous and can deal with the covariates properly. They allowed analyzing the association between the gender composition of the sample and the way the test AUDIT behaves in the example.

  17. Multiple treatment comparison meta-analyses: a step forward into complexity

    Directory of Open Access Journals (Sweden)

    Mills E

    2011-05-01

    Full Text Available Edward J Mills1, Nick Bansback2,8, Isabella Ghement3, Kristian Thorlund4, Steven Kelly5, Milo A Puhan6, James Wright71Faculty of Health Sciences, University of Ottawa, Ottawa, ON, Canada; 2Centre for Health Evaluation and Outcomes Sciences (CHEOS, University of British Columbia, Vancouver, BC, Canada; 3Ghement Statistical Consulting Company, Richmond, BC, Canada; 4Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada; 5Department of Outcomes Research and Evidence Based Medicine, Pfizer Ltd, Walton Oaks, UK; 6Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA; 7Department of Oncology and Medicine, McMaster University, Hamilton, ON, Canada; 8School of Population and Public Health, University of British Columbia, Vancouver, BC, CanadaAbstract: The use of meta-analysis has become increasingly useful for clinical and policy decision making. A recent development in meta-analysis, multiple treatment comparison (MTC meta-analysis, provides inferences on the comparative effectiveness of interventions that may have never been directly evaluated in clinical trials. This new approach may be confusing for clinicians and methodologists and raises specific challenges relevant to certain areas of medicine. This article addresses the methodological concepts of MTC meta-analysis, including issues of heterogeneity, choice of model, and adequacy of sample sizes. We address domain-specific challenges relevant to disciplines of medicine, including baseline risks of patient populations. We conclude that MTC meta-analysis is a useful tool in the context of comparative effectiveness and requires further study, as its utility and transparency will likely predict its uptake by the research and clinical community.Keywords: network, multiple treatment comparison, mixed treatment comparison, meta-analysis

  18. Multistage genome-wide association meta-analyses identified two new loci for bone mineral density.

    Science.gov (United States)

    Zhang, Lei; Choi, Hyung Jin; Estrada, Karol; Leo, Paul J; Li, Jian; Pei, Yu-Fang; Zhang, Yinping; Lin, Yong; Shen, Hui; Liu, Yao-Zhong; Liu, Yongjun; Zhao, Yingchun; Zhang, Ji-Gang; Tian, Qing; Wang, Yu-ping; Han, Yingying; Ran, Shu; Hai, Rong; Zhu, Xue-Zhen; Wu, Shuyan; Yan, Han; Liu, Xiaogang; Yang, Tie-Lin; Guo, Yan; Zhang, Feng; Guo, Yan-fang; Chen, Yuan; Chen, Xiangding; Tan, Lijun; Zhang, Lishu; Deng, Fei-Yan; Deng, Hongyi; Rivadeneira, Fernando; Duncan, Emma L; Lee, Jong Young; Han, Bok Ghee; Cho, Nam H; Nicholson, Geoffrey C; McCloskey, Eugene; Eastell, Richard; Prince, Richard L; Eisman, John A; Jones, Graeme; Reid, Ian R; Sambrook, Philip N; Dennison, Elaine M; Danoy, Patrick; Yerges-Armstrong, Laura M; Streeten, Elizabeth A; Hu, Tian; Xiang, Shuanglin; Papasian, Christopher J; Brown, Matthew A; Shin, Chan Soo; Uitterlinden, André G; Deng, Hong-Wen

    2014-04-01

    Aiming to identify novel genetic variants and to confirm previously identified genetic variants associated with bone mineral density (BMD), we conducted a three-stage genome-wide association (GWA) meta-analysis in 27 061 study subjects. Stage 1 meta-analyzed seven GWA samples and 11 140 subjects for BMDs at the lumbar spine, hip and femoral neck, followed by a Stage 2 in silico replication of 33 SNPs in 9258 subjects, and by a Stage 3 de novo validation of three SNPs in 6663 subjects. Combining evidence from all the stages, we have identified two novel loci that have not been reported previously at the genome-wide significance (GWS; 5.0 × 10(-8)) level: 14q24.2 (rs227425, P-value 3.98 × 10(-13), SMOC1) in the combined sample of males and females and 21q22.13 (rs170183, P-value 4.15 × 10(-9), CLDN14) in the female-specific sample. The two newly identified SNPs were also significant in the GEnetic Factors for OSteoporosis consortium (GEFOS, n = 32 960) summary results. We have also independently confirmed 13 previously reported loci at the GWS level: 1p36.12 (ZBTB40), 1p31.3 (GPR177), 4p16.3 (FGFRL1), 4q22.1 (MEPE), 5q14.3 (MEF2C), 6q25.1 (C6orf97, ESR1), 7q21.3 (FLJ42280, SHFM1), 7q31.31 (FAM3C, WNT16), 8q24.12 (TNFRSF11B), 11p15.3 (SOX6), 11q13.4 (LRP5), 13q14.11 (AKAP11) and 16q24 (FOXL1). Gene expression analysis in osteogenic cells implied potential functional association of the two candidate genes (SMOC1 and CLDN14) in bone metabolism. Our findings independently confirm previously identified biological pathways underlying bone metabolism and contribute to the discovery of novel pathways, thus providing valuable insights into the intervention and treatment of osteoporosis.

  19. A critical appraisal of the methodology and quality of evidence of systematic reviews and meta-analyses of traditional Chinese medical nursing interventions: a systematic review of reviews.

    Science.gov (United States)

    Jin, Ying-Hui; Wang, Guo-Hao; Sun, Yi-Rong; Li, Qi; Zhao, Chen; Li, Ge; Si, Jin-Hua; Li, Yan; Lu, Cui; Shang, Hong-Cai

    2016-11-14

    To assess the methodology and quality of evidence of systematic reviews and meta-analyses of traditional Chinese medical nursing (TCMN) interventions in Chinese journals. These interventions include acupressure, massage, Tai Chi, Qi Gong, electroacupuncture and use of Chinese herbal medicines-for example, in enemas, foot massage and compressing the umbilicus. A systematic literature search for systematic reviews and meta-analyses of TCMN interventions was performed. Review characteristics were extracted. The methodological quality and the quality of the evidence were evaluated using the Assessment of Multiple Systematic Reviews (AMSTAR) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) approaches. We included 20 systematic reviews and meta-analyses, and a total of 11 TCMN interventions were assessed in the 20 reviews. The compliance with AMSTAR checklist items ranged from 4.5 to 8 and systematic reviews/meta-analyses were, on average, of medium methodological quality. The quality of the evidence we assessed ranged from very low to moderate; no high-quality evidence was found. The top two causes for downrating confidence in effect estimates among the 31 bodies of evidence assessed were the risk of bias and inconsistency. There is room for improvement in the methodological quality of systematic reviews/meta-analyses of TCMN interventions published in Chinese journals. Greater efforts should be devoted to ensuring a more comprehensive search strategy, clearer specification of the interventions of interest in the eligibility criteria and identification of meaningful outcomes for clinicians and patients (consumers). The overall quality of evidence among reviews remains suboptimal, which raise concerns about their roles in influencing clinical practice. Thus, the conclusions in reviews we assessed must be treated with caution and their roles in influencing clinical practice should be limited. A critical appraisal of systematic reviews/meta-analyses

  20. Age and sex as moderators of the placebo response – an evaluation of systematic reviews and meta-analyses across medicine.

    Science.gov (United States)

    Weimer, Katja; Colloca, Luana; Enck, Paul

    2015-01-01

    Predictors of the placebo response (PR) in randomized controlled trials (RCT) have been searched for ever since RCT have become the standard for testing novel therapies and age and gender are routinely documented data in all trials irrespective of the drug tested, its indication, and the primary and secondary end points chosen. To evaluate whether age and gender have been found to be reliable predictors of the PR across medical subspecialties, we extracted 75 systematic reviews, meta-analyses, and meta-regressions performed in major medical areas (neurology, psychiatry, internal medicine) known for high PR rates. The literature database used contains approximately 2,500 papers on various aspects of the genuine PR. These ‘meta-analyses’ were screened for statistical predictors of the PR across multiple RCT, including age and gender, but also other patient-based and design-based predictors of higher PR rates. Retrieved papers were sorted for areas and disease categories. Only 15 of the 75 analyses noted an effect of younger age to be associated with higher PR, and this was predominantly in psychiatric conditions but not in depression, and internal medicine but not in gastroenterology. Female gender was associated with higher PR in only 3 analyses. Among the patient-based predictors, the most frequently noted factor was lower symptom severity at baseline, and among the design- based factors, it was a randomization ratio that selected more patients to drugs than to placebo, more frequent study visits, and more recent trials that were associated with higher PR rates. While younger age may contribute to the PR in some conditions, sex does not. There is currently no evidence that the PR is different in the elderly. PR are, however, markedly influenced by the symptom severity at baseline, and by the likelihood of receiving active treatment in placebo- controlled trials. © 2014 S. Karger AG, Basel.

  1. Non-skeletal health effects of vitamin D supplementation: A systematic review on findings from meta-analyses summarizing trial data

    Science.gov (United States)

    Bislev, Lise Sofie; Cashman, Kevin D.; Eiríksdottir, Gudny; Gaksch, Martin; Grübler, Martin; Grimnes, Guri; Gudnason, Vilmundur; Lips, Paul; Pilz, Stefan; van Schoor, Natasja M.; Kiely, Mairead; Jorde, Rolf

    2017-01-01

    Background A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D (25OHD) levels on non-skeletal outcomes. We performed a systematic quantitative review on characteristics of randomized clinical trials (RCTs) included in meta-analyses (MAs) on non-skeletal effects of vitamin D supplementation. Methods and findings We identified systematic reviews (SR) reporting summary data in terms of MAs of RCTs on selected non-skeletal outcomes. For each outcome, we summarized the results from available SRs and scrutinized included RCTs for a number of predefined characteristics. We identified 54 SRs including data from 210 RCTs. Most MAs as well as the individual RCTs reported null-findings on risk of cardiovascular diseases, type 2 diabetes, weight-loss, and malignant diseases. Beneficial effects of vitamin D supplementation was reported in 1 of 4 MAs on depression, 2 of 9 MAs on blood pressure, 3 of 7 MAs on respiratory tract infections, and 8 of 12 MAs on mortality. Most RCTs have primarily been performed to determine skeletal outcomes, whereas non-skeletal effects have been assessed as secondary outcomes. Only one-third of the RCTs had low level of 25OHD as a criterion for inclusion and a mean baseline 25OHD level below 50 nmol/L was only present in less than half of the analyses. Conclusions Published RCTs have mostly been performed in populations without low 25OHD levels. The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels. PMID:28686645

  2. Adverse Events Associated with Flumazenil Treatment for the Management of Suspected Benzodiazepine Intoxication--A Systematic Review with Meta-Analyses of Randomised Trials.

    Science.gov (United States)

    Penninga, Elisabeth I; Graudal, Niels; Ladekarl, Morten Baekbo; Jürgens, Gesche

    2016-01-01

    Flumazenil is used for the reversal of benzodiazepine overdose. Serious adverse events (SAEs) including seizures and cardiac arrhythmias have been reported in patients treated with flumazenil, and the clinical advantage of flumazenil treatment has been questioned. The objective was to assess the risk of (S)AEs associated with the use of flumazenil in patients with impaired consciousness due to known or suspected benzodiazepine overdose. Studies included in the meta-analyses were identified by literature search in Medline, Cochrane Library and Embase using combinations of the words flumazenil, benzodiazepines, anti-anxiety agents, poisoning, toxicity and overdose. Randomised clinical trials (RCTs) in verified or suspected benzodiazepine overdose patients comparing treatment with flumazenil versus placebo were included. Pre-defined outcome measures were AEs, SAEs and mortality. Thirteen trials with a total of 994 randomised (990 evaluable) patients were included. AEs were significantly more common in the flumazenil group (138/498) compared with the placebo group (47/492) (risk ratio: 2.85; 95% confidence interval: 2.11-3.84; p risk ratio: 3.81; 95% CI: 1.28-11.39; p = 0.02). The most common AEs in the flumazenil group were agitation and gastrointestinal symptoms, whereas the most common SAEs were supraventricular arrhythmia and convulsions. No patients died during the blinded phase of the RCTs. The use of flumazenil in a population admitted at the emergency department with known or suspected benzodiazepine intoxication is associated with a significantly increased risk of (S)AEs compared with placebo. Flumazenil should not be used routinely, and the harms and benefits should be considered carefully in every patient.

  3. Cardiovascular and Renal Outcomes of Renin-Angiotensin System Blockade in Adult Patients with Diabetes Mellitus: A Systematic Review with Network Meta-Analyses.

    Directory of Open Access Journals (Sweden)

    Ferrán Catalá-López

    2016-03-01

    respect to all-cause mortality, cardiovascular mortality, myocardial infarction, stroke, angina pectoris, hospitalization for heart failure, ESRD, or doubling serum creatinine. Findings were limited by the clinical and methodological heterogeneity of the included studies. Potential inconsistency was identified in network meta-analyses of stroke and angina pectoris, limiting the conclusiveness of findings for these single endpoints.In adults with diabetes, comparisons of different RAS blockers showed similar effects of ACE inhibitors and ARBs on major cardiovascular and renal outcomes. Compared with monotherapies, the combination of an ACE inhibitor and an ARB failed to provide significant benefits on major outcomes. Clinicians should discuss the balance between benefits, costs, and potential harms with individual diabetes patients before starting treatment.PROSPERO CRD42014014404.

  4. Cardiovascular and Renal Outcomes of Renin–Angiotensin System Blockade in Adult Patients with Diabetes Mellitus: A Systematic Review with Network Meta-Analyses

    Science.gov (United States)

    Catalá-López, Ferrán; Macías Saint-Gerons, Diego; González-Bermejo, Diana; Rosano, Giuseppe M.; Davis, Barry R.; Ridao, Manuel; Zaragoza, Abel; Montero-Corominas, Dolores; Tobías, Aurelio; de la Fuente-Honrubia, César; Tabarés-Seisdedos, Rafael; Hutton, Brian

    2016-01-01

    differences were showed between ACE inhibitors and ARBs with respect to all-cause mortality, cardiovascular mortality, myocardial infarction, stroke, angina pectoris, hospitalization for heart failure, ESRD, or doubling serum creatinine. Findings were limited by the clinical and methodological heterogeneity of the included studies. Potential inconsistency was identified in network meta-analyses of stroke and angina pectoris, limiting the conclusiveness of findings for these single endpoints. Conclusions In adults with diabetes, comparisons of different RAS blockers showed similar effects of ACE inhibitors and ARBs on major cardiovascular and renal outcomes. Compared with monotherapies, the combination of an ACE inhibitor and an ARB failed to provide significant benefits on major outcomes. Clinicians should discuss the balance between benefits, costs, and potential harms with individual diabetes patients before starting treatment. Review registration PROSPERO CRD42014014404 PMID:26954482

  5. Circulating adiponectin levels in relation to carotid atherosclerotic plaque presence, ischemic stroke risk, and mortality: A systematic review and meta-analyses.

    Science.gov (United States)

    Gorgui, Jessica; Gasbarrino, Karina; Georgakis, Marios K; Karalexi, Maria A; Nauche, Bénédicte; Petridou, Eleni Th; Daskalopoulou, Stella S

    2017-04-01

    Low circulating levels of adiponectin, an anti-inflammatory and vasculoprotective adipokine, are associated with obesity, type 2 diabetes, and atherosclerotic disease. Presence of unstable plaques in the carotid artery is a known etiological factor causing ischemic strokes. Herein, we systematically reviewed the association between circulating adiponectin and progression of carotid atherosclerotic disease, particularly evaluating the occurrence of (1) carotid atherosclerotic plaques, (2) ischemic stroke, and (3) mortality in subjects who suffered a previous ischemic stroke. Medline, Embase, Biosis, Scopus, Web of Science, and Pubmed were searched for published studies and conference abstracts. The effect size and 95% confidence intervals (CIs) of the individual studies were pooled using fixed-effect or random-effect models. The quality of the eligible studies was evaluated using the Newcastle-Ottawa quality assessment scale. Sensitivity, subgroup, and meta-regression analyses were performed to address the impact of various risk factors on the association between adiponectin and ischemic stroke risk. Twelve studies fulfilled the inclusion criteria for 3 independent meta-analyses. The association of increasing circulating adiponectin levels (5μg/mL-increment) with presence of carotid plaque was not conclusive (n=327; OR: 1.07; 95% CI: 0.85-1.35; 2 studies), whereas high adiponectin levels showed a significant 8% increase in risk of ischemic stroke (n=13,683; 7 studies), with a more sizable association observed among men compared to women. HDL was observed to have a marginal effect on the association between adiponectin and ischemic stroke, while other evaluated parameters were not found to be effect modifiers. A non-significant association of adiponectin with mortality was yielded (n=663; OR: 2.58; 95% CI: 0.69-9.62; 3 studies). Although no publication bias was evident, there was significant between-study heterogeneity in most analyses. It appears that the direction

  6. Diet and ADHD, Reviewing the Evidence: A Systematic Review of Meta-Analyses of Double-Blind Placebo-Controlled Trials Evaluating the Efficacy of Diet Interventions on the Behavior of Children with ADHD

    Science.gov (United States)

    Pelsser, Lidy M.; Frankena, Klaas; Toorman, Jan; Rodrigues Pereira, Rob

    2017-01-01

    Introduction Attention-deficit/hyperactivity disorder (ADHD) is a debilitating mental health problem hampering the child’s development. The underlying causes include both genetic and environmental factors and may differ between individuals. The efficacy of diet treatments in ADHD was recently evaluated in three reviews, reporting divergent and confusing conclusions based on heterogeneous studies and subjects. To address this inconsistency we conducted a systematic review of meta-analyses of double-blind placebo-controlled trials evaluating the effect of diet interventions (elimination and supplementation) on ADHD. Methods Our literature search resulted in 14 meta-analyses, six of which confined to double-blind placebo-controlled trials applying homogeneous diet interventions, i.e. artificial food color (AFC) elimination, a few-foods diet (FFD) and poly-unsaturated fatty acid (PUFA) supplementation. Effect sizes (ES) and Confidence intervals (CI) of study outcomes were depicted in a forest plot. I2 was calculated to assess heterogeneity if necessary and additional random effects subgroup meta-regression was conducted if substantial heterogeneity was present. Results The AFC ESs were 0.44 (95% CI: 0.16–0.72, I2 = 11%) and 0.21 (95% CI: -0.02–0.43, I2 = 68%) [parent ratings], 0.08 (95% CI: -0.07–0.24, I2 = 0%) [teacher ratings] and 0.11 (95% CI: -0.13–0.34, I2 = 12%) [observer ratings]. The FFD ESs were 0.80 (95% CI: 0.41–1.19, I2 = 61%) [parent ratings] and 0.51 (95% CI: -0.02–1.04, I2 = 72%) [other ratings], while the PUFA ESs were 0.17 (95% CI: -0.03–0.38, I2 = 38%) [parent ratings], -0.05 (95% CI: -0.27–0.18, I2 = 0%) [teacher ratings] and 0.16 (95% CI: 0.01–0.31, I2 = 0%) [parent and teacher ratings]. Three meta-analyses (two FFD and one AFC) resulted in high I2 without presenting subgroup results. The FFD meta-analyses provided sufficient data to perform subgroup analyses on intervention type, resulting in a decrease of heterogeneity to 0

  7. Methylphenidate for attention-deficit/hyperactivity disorder in children and adolescents: Cochrane systematic review with meta-analyses and trial sequential analyses of randomised clinical trials.

    Science.gov (United States)

    Storebø, Ole Jakob; Krogh, Helle B; Ramstad, Erica; Moreira-Maia, Carlos R; Holmskov, Mathilde; Skoog, Maria; Nilausen, Trine Danvad; Magnusson, Frederik L; Zwi, Morris; Gillies, Donna; Rosendal, Susanne; Groth, Camilla; Rasmussen, Kirsten Buch; Gauci, Dorothy; Kirubakaran, Richard; Forsbøl, Bente; Simonsen, Erik; Gluud, Christian

    2015-11-25

    Is methylphenidate beneficial or harmful for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children and adolescents? Electronic databases were searched up to February 2015 for parallel and crossover randomised clinical trials comparing methylphenidate with placebo or no intervention in children and adolescents with ADHD. Meta-analyses and trial sequential analyses (TSA) were conducted. Quality was assessed using GRADE. Teachers, parents, and observers rated ADHD symptoms and general behaviour. The analyses included 38 parallel group trials (n=5111, median treatment duration 49 days) and 147 crossover trials (n=7134, 14 days). The average age across all studies was 9.7 years. The analysis suggested a beneficial effect of methylphenidate on teacher rated symptoms in 19 parallel group trials (standardised mean difference (SMD) -0.77, n=1698), corresponding to a mean difference of -9.6 points on the ADHD rating scale. There was no evidence that methylphenidate was associated with an increase in serious adverse events (risk ratio 0.98, nine trials, n=1532; TSA adjusted intervention effect RR 0.91). Methylphenidate was associated with an increased risk of non-serious adverse events (1.29, 21 trials, n=3132; TSA adjusted RR 1.29). Teacher rated general behaviour seemed to improve with methylphenidate (SMD -0.87, five trials, n=668) A change of 7 points on the child health questionnaire (CHQ) has been deemed a minimal clinically relevant difference. The change reported in a meta-analysis of three trials corresponds to a mean difference of 8.0 points on the CHQ (range 0-100 points), which suggests that methylphenidate may improve parent reported quality of life (SMD 0.61, three trials, n=514). 96.8% of trials were considered high risk of bias trials according to the Cochrane guidelines. All outcomes were assessed very low quality according to GRADE. The results suggest that among children and adolescents with a diagnosis of ADHD, methylphenidate may

  8. Dose doubling, relative potency, and dose equivalence of potassium-sparing diuretics affecting blood pressure and serum potassium: systematic review and meta-analyses.

    Science.gov (United States)

    Roush, George C; Ernst, Michael E; Kostis, John B; Yeasmin, Shamima; Sica, Domenic A

    2016-01-01

    Potassium-sparing diuretics (PSDs) are valuable antihypertensives with additional benefits unrelated to control of systolic blood pressure (SBP). However, their key parameters affecting SBP and serum potassium are poorly defined, fostering underutilization. Consequently, we conducted systematic reviews and meta-analyses, yielding 3668 articles and ultimately 84 randomized comparisons. For office SBP, overall placebo-adjusted changes were triamterene -1.9 (low dose only), amiloride -9.9, spironolactone -13.2, and eplerenone -9.2. Differences in antihypertensive effect were due to potency rather than efficacy. Doubling amiloride, eplerenone, and spironolactone doses reduced SBP (95% confidence limits) on average by -2.3 (-3.1, -1.5). Relative antihypertensive potencies were spironolactone>amiloride>eplerenone. Spironolactone had significantly greater antihypertensive potency than amiloride, -4.0 (-7.4, -0.6), and eplerenone, -5.5 (-7.4, -3.6). Dose equivalencies were eplerenone-spironolactone 4.5-to-1 (e.g., eplerenone 125∼spironolactone 25), amiloride-spironolactone 3.3-to-1, and eplerenone-amiloride 1.4-to-1. Increases in serum potassium from amiloride and spironolactone at commonly used doses averaged 0.14-0.29 mEq/l; the dose doubling effect was 0.16 (0.10, 0.22). Spironolactone caused greater hyperkalemia than amiloride across their dose ranges: 0.14, P = 0.043. Seven features make important bias unlikely: a comprehensive literature search, adjustment for covariates, all models explaining 95-100% of the between-study variability, similar dose doubling effects among PSDs, two different methods giving the same potency sequence, similar results from double blind comparisons, and similar results for eplerenone versus spironolactone from analysing direct comparison data (i.e., no meta-regression) for office and 24-h SBP. This synthesis accomplishes for PSDs what has already been achieved for thiazide-type diuretics and other antihypertensives and can guide

  9. Psychological Interventions for the Management of Glycemic and Psychological Outcomes of Type 2 Diabetes Mellitus in China: A Systematic Review and Meta-Analyses of Randomized Controlled Trials.

    Science.gov (United States)

    Chapman, Anna; Liu, Shuo; Merkouris, Stephanie; Enticott, Joanne C; Yang, Hui; Browning, Colette J; Thomas, Shane A

    2015-01-01

    China has the largest number of type 2 diabetes mellitus (T2DM) cases globally, and T2DM management has become a critical public health issue in China. Individuals with T2DM have an increased risk of developing mental health disorders, psychological disturbances, and functional problems associated with living with their condition. Previous systematic reviews have demonstrated that, generally, psychological interventions are effective in the management of T2DM-related outcomes; however, these reviews have predominantly included studies conducted within English-speaking countries and have not determined the efficacy of the varying types of psychological interventions. As such, this paper aims to synthesize evidence and quantify the efficacy of psychological therapies for the management of glycemic and psychological outcomes of T2DM in China, relative to control conditions. A systematic search (MEDLINE, PsycINFO, CINAHL, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, and Wangfang Data) for all years to December 2014 identified all available literature. Eligibility criteria included: peer-reviewed journal articles, randomized controlled trials (RCTs) assessing the efficacy of a psychological therapy for the management of T2DM, adult participants (≥18 years) diagnosed with T2DM or non-insulin-dependent diabetes mellitus, and Chinese speaking participants only (in mainland China). Outcome measures were glycated hemoglobin, blood glucose concentration, depression, anxiety, and quality of life. Effect sizes were pooled using a random effects model. Negative effect sizes corresponded to positive outcomes favoring the intervention. Forty-five RCTs were eligible for the meta-analyses. Cognitive behavioral therapy (CBT) and motivational interviewing (MI) were more effective than the control condition in the reduction of glycated hemoglobin [CBT: -0.97 (95% CI -1.37 to -0.57); MI: -0.71 (95% CI -1.00 to -0.43)]. CBT and client

  10. Psychological interventions for the management of glycemic and psychological outcomes of type 2 diabetes mellitus in China: A systematic review and meta-analyses of randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Anna eChapman

    2015-11-01

    Full Text Available IntroductionChina has the largest number of type 2 diabetes mellitus (T2DM cases globally and T2DM management has become a critical public health issue in China. Individuals with T2DM have an increased risk of developing mental health disorders, psychological disturbances and functional problems associated with living with their condition. Previous systematic reviews have demonstrated that, generally, psychological interventions are effective in the management of T2DM related outcomes; however these reviews have predominantly included studies conducted within English speaking countries, and have not determined the efficacy of the varying types of psychological interventions. As such, this paper aims to synthesize evidence and quantify the efficacy of psychological therapies for the management of glycemic and psychological outcomes of T2DM in China, relative to control conditions. MethodsA systematic search (MEDLINE, PsycINFO, CINAHL, Cochrane Central Register of Controlled Trials, CNKI, Wangfang Data for all years to December 2014 identified all available literature. Eligibility criteria included: Peer reviewed journal articles; RCTs assessing the efficacy of a psychological therapy for the management of T2DM; adults diagnosed with T2DM or non-insulin dependent diabetes mellitus; Chinese speaking participants (in mainland China. Outcome measures were glycated hemoglobin, blood glucose concentration, depression, anxiety and quality of life. Effect sizes were pooled using a random effects model. Negative effect sizes corresponded to positive outcomes favoring the intervention. Results45 RCTs were eligible for the meta-analyses. Cognitive behavioral therapy (CBT and motivational interviewing (MI were more effective than the control condition in the reduction of glycated hemoglobin (CBT: -0·97 [95% CI -1·37 to -0·57]; MI -0·71 [95% CI -1·00 to -0·43]. CBT and client-centered therapy (CCT were also associated with reductions in depression and

  11. Meta-analyses on studies about the identification and attention of the gifted and talented in Peru

    OpenAIRE

    Blumen, Sheyla

    2013-01-01

    Are gifted and talented identification programs scientifically based, fair and unbiased? Aregifted enrichment programs effective? Financia! pressures from NGOs and prívate founda­ tions, changes in national educational policies, as well as multicultural issues, are forcing psychologists and educators to face these questions. Our review discusses the important changes that have begun to alter the gifted and talented field in Latin America, especially in Peru. It describes recent empirical stud...

  12. Impact of searching clinical trial registries in systematic reviews of pharmaceutical treatments: methodological systematic review and reanalysis of meta-analyses.

    Science.gov (United States)

    Baudard, Marie; Yavchitz, Amélie; Ravaud, Philippe; Perrodeau, Elodie; Boutron, Isabelle

    2017-02-17

    Objective To evaluate the impact of searching clinical trial registries in systematic reviews.Design Methodological systematic review and reanalyses of meta-analyses.Data sources Medline was searched to identify systematic reviews of randomised controlled trials (RCTs) assessing pharmaceutical treatments published between June 2014 and January 2015. For all systematic reviews that did not report a trial registry search but reported the information to perform it, the World Health Organization International Trials Registry Platform (WHO ICTRP search portal) was searched for completed or terminated RCTs not originally included in the systematic review.Data extraction For each systematic review, two researchers independently extracted the outcomes analysed, the number of patients included, and the treatment effect estimated. For each RCT identified, two researchers independently determined whether the results were available (ie, posted, published, or available on the sponsor website) and extracted the data. When additional data were retrieved, we reanalysed meta-analyses and calculated the weight of the additional RCTs and the change in summary statistics by comparison with the original meta-analysis.Results Among 223 selected systematic reviews, 116 (52%) did not report a search of trial registries; 21 of these did not report the information to perform the search (key words, search date). A search was performed for 95 systematic reviews; for 54 (57%), no additional RCTs were found and for 41 (43%) 122 additional RCTs were identified. The search allowed for increasing the number of patients by more than 10% in 19 systematic reviews, 20% in 10, 30% in seven, and 50% in four. Moreover, 63 RCTs had results available; the results for 45 could be included in a meta-analysis. 14 systematic reviews including 45 RCTs were reanalysed. The weight of the additional RCTs in the recalculated meta-analyses ranged from 0% to 58% and was greater than 10% in five of 14 systematic

  13. Comparison of Approaches for Stroke Prophylaxis in Patients with Non-Valvular Atrial Fibrillation: Network Meta-Analyses of Randomized Controlled Trials

    Science.gov (United States)

    Patel, Nirav; Hashim, Taimoor; Godara, Hemant; Ather, Sameer; Arora, Garima; Pasala, Tilak; Whitfield, Thomas T.; McGiffin, David C.; Ahmed, Mustafa I.; Lloyd, Steven G.; Limdi, Nita A.

    2016-01-01

    Background Multiple novel oral anticoagulants and left atrial appendage closure devices (WATCHMAN) have been tested against dose-adjusted vitamin K antagonists in randomized controlled trials for stroke prophylaxis in non-valvular atrial fibrillation. No direct comparisons of these strategies are available from randomized controlled trials. We conducted the current analyses by combining efficacy and safety characteristics of all FDA approved stroke prophylaxis treatment strategies for patients with non-valvular atrial fibrillation. Materials and Methods We searched SCOPUS from 1945 till October 2015 for randomized controlled trials comparing these strategies and reporting efficacy and safety outcomes. Six randomized controlled trials were identified and included in the final analyses and review. We followed PRISMA guidelines for network meta-analyses while reporting the current analyses. We collected data on ischemic stroke, major bleeding, and the composite primary safety endpoint as defined by various randomized controlled trials. Network meta-analyses were conducted using consistency and inconsistency models for efficacy and safety outcomes. Surface under the cumulative ranking curve were then utilized to cluster rank these treatments for safety and efficacy. Results Six randomized controlled trials with 59,627 patients comparing six treatment strategies were eligible for the analyses. All prophylaxis strategies had comparable rates of ischemic stroke. Apixaban was associated with the least number of primary safety endpoint events as compared with all other treatments. In the cluster analyses assessing safety and efficacy, apixaban, edoxaban and dabigatran ranked best followed by vitamin K antagonists and rivaroxaban, whereas the WATCHMAN left atrial appendage closure device ranked last. Conclusions Dose-adjusted vitamin K antagonists, novel oral anticoagulants, and the WATCHMAN left atrial appendage closure devices are equally efficacious for ischemic stroke

  14. The effectiveness of home-based HIV counseling and testing on reducing stigma and risky sexual behavior among adults and adolescents: A systematic review and meta-analyses.

    Science.gov (United States)

    Feyissa, Garumma Tolu; Lockwood, Craig; Munn, Zachary

    2015-07-17

    -analysis software provided by Joanna Briggs Institute. Effect sizes were calculated using fixed effects model. Where the findings could not be pooled using meta-analyses, results were presented in a narrative form. Nine studies were included in this review, five of them reporting on stigma and related outcomes, three of them on sexual behavior and four of them on clinical outcomes. Meta-analysis indicated that the risk of observing any stigmatizing behavior in the community was 16% (RR=0.84, 95% CI 0.79 to 0.89] lower among the participants exposed to home-based HCT when compared to the risk among those participants not exposed to home-based HCT. The risk of experiencing any stigmatizing behavior by HIV positive patients was 37% (RR 0.63, 95% CI 0.45 to 0.88) lower among the intervention population compared to the risk among the control population. The risk of intimate partner violence was 34% (RR 0.66, 95% CI 0.49 to 0.89) lower among participants exposed to home-based HCT when compared to the risk among participants in the control arm. Compared to the control arm, the risk of reporting more than one sexual partner was 58% (RR 0.42, 95% CI 0.31 to 0.58) lower among participants exposed to home-based HCT. The risk of having any casual sexual partner in the past three months was 51% (RR 0.49, 95% CI 0.40 to 0.59) lower among the population exposed to home-based HCT when compared to the risk among those participants not exposed to home-based HCT. The risk of having ever been forced for sex among participants exposed to home-based HCT was 20% (RR 0.8, 0.56 to 1.14) lower when compared to the risk among the control arm; however this result was not statistically significant and the wide confidence interval indicates that the risk estimate was imprecise. Home-based HCT is protective against intimate partner violence, stigmatizing behavior, having multiple sexual partners, and having casual sexual partners. The low quality of studies included makes it difficult to formulate clear

  15. Meta-analyses and other methodological issues in meditation research: Reply to Orme-Johnson and Dillbeck (2014).

    Science.gov (United States)

    Sedlmeier, Peter; Eberth, Juliane; Schwarz, Marcus

    2014-03-01

    We are grateful to Orme-Johnson and Dillbeck (2014) for raising several potential methodological concerns they have with our meta-analysis of the psychological effects of meditation and for thereby providing us with the opportunity to clarify these points. Orme-Johnson and Dillbeck raised 4 points that they believed might have led to unfair treatment of studies that reported the effects of transcendental meditation (TM). First, they were concerned with the way we aggregated effects over different categories of variables. Second, they disagreed with our contention that there might have been some upward bias in the effects reported for TM studies. Third, they argued that the results from TM studies do not differ depending on whether studies were done by researchers affiliated with TM institutions, and 4th, they questioned the completeness of our selection of TM studies. We still believe that our methodology for reporting study results was justified on theoretical grounds and argue that the results for all variable categories are readily available in our analysis. We also still find some indication of upward bias for TM studies, even using the method they propose. We cannot say much regarding author affiliation because we did not raise that point, and, last, we have to concede that we indeed missed some TM studies. Yet this omission did not have any substantial practical consequences concerning our conclusions. We end with a short discussion about how meditation research should be conducted in the future.

  16. Association of atopic diseases and attention-deficit/hyperactivity disorder: A systematic review and meta-analyses.

    Science.gov (United States)

    Schans, Jurjen van der; Çiçek, Rukiye; de Vries, Tjalling W; Hak, Eelko; Hoekstra, Pieter J

    2017-03-01

    Over the last decades, the hypothesis has been raised that an atopic response could lead to the development of attention-deficit/hyperactivity disorder (ADHD). This study systematically reviews the observational cross-sectional and longitudinal studies that assessed the association between atopic disorders including asthma, atopic eczema, allergic rhinitis, and ADHD in children and adolescents. For longitudinal studies, a weighted Mantel-Haenszel odds ratio of these associations was estimated. The majority of cross-sectional and longitudinal studies reported a statistically significant positive association. The meta-analysis of longitudinal studies revealed an overall weighted odds ratio for asthma of 1.34 (95% confidence interval [CI] 1.24-1.44), 1.32 (95% CI 1.20-1.45) for atopic eczema, and 1.52 (95% CI 1.43-1.63) for allergic rhinitis. Heterogeneity of study data was low (I(2): 0%, p=0.46 and p=0.64, respectively) for both studies examining asthma and eczema but substantial for rhinitis studies (I(2): 82%, p=0.004). This current systematic review provides strong evidence that ADHD is associated with atopic diseases and that individuals have a 30% to 50% greater chance of developing ADHD compared to controls.

  17. The effects of clinical and statistical heterogeneity on the predictive values of results from meta-analyses

    NARCIS (Netherlands)

    Melsen, W G; Rovers, M M; Bonten, M J M; Bootsma, M C J

    2014-01-01

    Variance between studies in a meta-analysis will exist. This heterogeneity may be of clinical, methodological or statistical origin. The last of these is quantified by the I(2) -statistic. We investigated, using simulated studies, the accuracy of I(2) in the assessment of heterogeneity and the effec

  18. The link between dissociation and both suicide attempts and non-suicidal self-injury: Meta-analyses.

    Science.gov (United States)

    Calati, Raffaella; Bensassi, Ismaïl; Courtet, Philippe

    2017-01-17

    Dissociative disorders (DD) are frequently associated with suicidal behaviors. We performed the first meta-analysis of studies comparing rates of suicide attempts (SA) and non-suicidal self-injury (NSSI) in psychiatric individuals with and without DD. We included: 1) studies comparing SA and NSSI rates in psychiatric individuals with and without DD; 2) studies comparing Dissociative Experiences Scale (DES) scores in both SA and NSSI psychiatric patients versus non SA and non NSSI ones. Cochrane Collaboration Review Manager Software and STROBE statement were used. Nineteen studies were included in the analyses. DD patients were more likely to report both previous SA and NSSI in comparison to non DD patients. Importantly, results remained highly significant in both outcomes but with no more heterogeneity when including studies using a DSM-based method to diagnose DD. Both SA and NSSI patients reported higher DES scores in comparison to non SA and non NSSI patients. The presence of DD diagnosis or higher DES scores seems to be related to both SA and NSSI in psychiatric patients. Hence, it may be reasonable to hypothesize the presence of a dissociative subtype in a subset of these patients, which should be considered as a transdiagnostic factor and should be carefully assessed.

  19. Reporting and Handling Missing Outcome Data in Mental Health: A Systematic Review of Cochrane Systematic Reviews and Meta-Analyses

    Science.gov (United States)

    Spineli, Loukia M.; Pandis, Nikolaos; Salanti, Georgia

    2015-01-01

    Objectives: The purpose of the study was to provide empirical evidence about the reporting of methodology to address missing outcome data and the acknowledgement of their impact in Cochrane systematic reviews in the mental health field. Methods: Systematic reviews published in the Cochrane Database of Systematic Reviews after January 1, 2009 by…

  20. Meta-Analyses of Vitamin D Intake, 25-Hydroxyvitamin D Status, Vitamin D Receptor Polymorphisms, and Colorectal Cancer Risk

    NARCIS (Netherlands)

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

    2011-01-01

    Background: Our objective was to conduct a systematic review and meta-analysis of prospective studies on colorectal cancer (CRC) and vitamin D intake and 25-hydroxyvitamin D status, as part of the World Cancer Research Fund Continuous Update Project. We also aimed at conducting meta-analysis of all

  1. Meta-Analyses of Vitamin D Intake, 25-Hydroxyvitamin D Status, Vitamin D Receptor Polymorphisms, and Colorectal Cancer Risk

    NARCIS (Netherlands)

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

    2011-01-01

    Background: Our objective was to conduct a systematic review and meta-analysis of prospective studies on colorectal cancer (CRC) and vitamin D intake and 25-hydroxyvitamin D status, as part of the World Cancer Research Fund Continuous Update Project. We also aimed at conducting meta-analysis of all

  2. Meta-analyses of vitamin D intake, 25-hydroxyvitamin D status, vitamin D receptor polymorphisms, and colorectal cancer risk

    NARCIS (Netherlands)

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

    2011-01-01

    BACKGROUND: Our objective was to conduct a systematic review and meta-analysis of prospective studies on colorectal cancer (CRC) and vitamin D intake and 25-hydroxyvitamin D status, as part of the World Cancer Research Fund Continuous Update Project. We also aimed at conducting meta-analysis of all

  3. Meta-analyses identify 13 loci associated with age at menopause and highlight DNA repair and immune pathways

    NARCIS (Netherlands)

    Stolk, Lisette; Perry, John R. B.; Chasman, Daniel I.; He, Chunyan; Mangino, Massimo; Sulem, Patrick; Barbalic, Maja; Broer, Linda; Byrne, Enda M.; Ernst, Florian; Esko, Tonu; Franceschini, Nora; Gudbjartsson, Daniel F.; Hottenga, Jouke-Jan; Kraft, Peter; McArdle, Patrick F.; Porcu, Eleonora; Shin, So-Youn; Smith, Albert V.; van Wingerden, Sophie; Zhai, Guangju; Zhuang, Wei V.; Albrecht, Eva; Alizadeh, Behrooz Z.; Aspelund, Thor; Bandinelli, Stefania; Lauc, Lovorka Barac; Beckmann, Jacques S.; Boban, Mladen; Boerwinkle, Eric; Broekmans, Frank J.; Burri, Andrea; Campbell, Harry; Chanock, Stephen J.; Chen, Constance; Cornelis, Marilyn C.; Corre, Tanguy; Coviello, Andrea D.; d'Adamo, Pio; Davies, Gail; de Faire, Ulf; de Geus, Eco J. C.; Deary, Ian J.; Dedoussis, George V. Z.; Deloukas, Panagiotis; Ebrahim, Shah; Eiriksdottir, Gudny; Emilsson, Valur; Eriksson, Johan G.; Fauser, Bart C. J. M.; Ferreli, Liana; Ferrucci, Luigi; Fischer, Krista; Folsom, Aaron R.; Garcia, Melissa E.; Gasparini, Paolo; Gieger, Christian; Glazer, Nicole; Grobbee, Diederick E.; Hall, Per; Haller, Toomas; Hankinson, Susan E.; Hass, Merli; Hayward, Caroline; Heath, Andrew C.; Hofman, Albert; Ingelsson, Erik; Janssens, A. Cecile J. W.; Johnson, Andrew D.; Karasik, David; Kardia, Sharon L. R.; Keyzer, Jules; Kiel, Douglas P.; Kolcic, Ivana; Kutalik, Zoltan; Lahti, Jari; Lai, Sandra; Laisk, Triin; Laven, Joop S. E.; Lawlor, Debbie A.; Liu, Jianjun; Lopez, Lorna M.; Louwers, Yvonne V.; Magnusson, Patrik K. E.; Marongiu, Mara; Martin, Nicholas G.; Klaric, Irena Martinovic; Masciullo, Corrado; McKnight, Barbara; Medland, Sarah E.; Melzer, David; Mooser, Vincent; Navarro, Pau; Newman, Anne B.; Nyholt, Dale R.; Onland-Moret, N. Charlotte; Palotie, Aarno; Pare, Guillaume; Parker, Alex N.; Pedersen, Nancy L.; Peeters, Petra H. M.; Pistis, Giorgio; Plump, Andrew S.; Polasek, Ozren; Pop, Victor J. M.; Psaty, Bruce M.; Raikkonen, Katri; Rehnberg, Emil; Rotter, Jerome I.; Rudan, Igor; Sala, Cinzia; Salumets, Andres; Scuteri, Angelo; Singleton, Andrew; Smith, Jennifer A.; Snieder, Harold; Soranzo, Nicole; Stacey, Simon N.; Starr, John M.; Stathopoulou, Maria G.; Stirrups, Kathleen; Stolk, Ronald P.; Styrkarsdottir, Unnur; Sun, Yan V.; Tenesa, Albert; Thorand, Barbara; Toniolo, Daniela; Tryggvadottir, Laufey; Tsui, Kim; Ulivi, Sheila; van Dam, Rob M.; van der Schouw, Yvonne T.; van Gils, Carla H.; van Nierop, Peter; Vink, Jacqueline M.; Visscher, Peter M.; Voorhuis, Marlies; Waeber, Gerard; Wallaschofski, Henri; Wichmann, H. Erich; Widen, Elisabeth; Wijnands-van Gent, Colette J. M.; Willemsen, Gonneke; Wilson, James F.; Wolffenbuttel, Bruce H. R.; Wright, Alan F.; Yerges-Armstrong, Laura M.; Zemunik, Tatijana; Zgaga, Lina; Zillikens, M. Carola; Zygmunt, Marek; Arnold, Alice M.; Boomsma, Dorret I.; Buring, Julie E.; Crisponi, Laura; Demerath, Ellen W.; Gudnason, Vilmundur; Harris, Tamara B.; Hu, Frank B.; Hunter, David J.; Launer, Lenore J.; Metspalu, Andres; Montgomery, Grant W.; Oostra, Ben A.; Ridker, Paul M.; Sanna, Serena; Schlessinger, David; Spector, Tim D.; Stefansson, Kari; Streeten, Elizabeth A.; Thorsteinsdottir, Unnur; Uda, Manuela; Uitterlinden, Andre G.; van Duijn, Cornelia M.; Voelzke, Henry; Murray, Anna; Murabito, Joanne M.; Visser, Jenny A.; Lunetta, Kathryn L.

    To newly identify loci for age at natural menopause, we carried out a meta-analysis of 22 genome-wide association studies (GWAS) in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 loci newly associated with age at natural

  4. An Analysis of Two Genome-wide Association Meta-analyses Identifies a New Locus for Broad Depression Phenotype

    NARCIS (Netherlands)

    Direk, Nese; Williams, Stephanie; Smith, Jennifer A.; Ripke, Stephan; Air, Tracy; Amare, Azmeraw T.; Amin, Najaf; Baune, Bernhard T.; Bennett, David A.; Blackwood, Douglas H. R.; Boomsma, Dorret; Breen, Gerome; Buttenschon, Henriette N.; Byrne, Enda M.; Borglum, Anders D.; Castelao, Enrique; Cichon, Sven; Clarke, Toni-Kim; Cornelis, Marilyn C.; Dannlowski, Udo; De Jager, Philip L.; Demirkan, Ayse; Domenici, Enrico; van Duijn, Cornelia M.; Dunn, Erin C.; Eriksson, Johan G.; Esko, Tonu; Faul, Jessica D.; Ferrucci, Luigi; Fornage, Myriam; de Geus, Eco; Gill, Michael; Gordon, Scott D.; Grabe, Hans Joergen; van Grootheest, Gerard; Hamilton, Steven P.; Hartman, Catharina A.; Heath, Andrew C.; Hek, Karin; Hofman, Albert; Homuth, Georg; Horn, Carsten; Hottenga, Jouke Jan; Kardia, Sharon L. R.; Kloiber, Stefan; Koenen, Karestan; Kutalik, Zoltan; Ladwig, Karl-Heinz; Lahti, Jari; Levinson, Douglas F.; Lewis, Cathryn M.; Lewis, Glyn; Li, Qingqin S.; Llewellyn, David J.; Lucae, Susanne; Lunetta, Kathryn L.; MacIntyre, Donald J.; Madden, Pamela; Martin, Nicholas G.; McIntosh, Andrew M.; Metspalu, Andres; Milaneschi, Yuri; Montgomery, Grant W.; Mors, Ole; Mosley, Thomas H.; Murabito, Joanne M.; Mueller-Myhsok, Bertram; Nothen, Markus M.; Nyholt, Dale R.; O'Donovan, Michael C.; Penninx, Brenda W.; Pergadia, Michele L.; Perlis, Roy; Potash, James B.; Preisig, Martin; Purcell, Shaun M.; Quiroz, Jorge A.; Raikkonen, Katri; Rice, John P.; Rietschel, Marcella; Rivera, Margarita; Schulze, Thomas G.; Shi, Jianxin; Shyn, Stanley; Sinnamon, Grant C.; Smit, Johannes H.; Smoller, Jordan W.; Snieder, Harold; Tanaka, Toshiko; Tansey, Katherine E.; Teumer, Alexander; Uher, Rudolf; Umbricht, Daniel; Van der Auwera, Sandra; Ware, Erin B.; Weir, David R.; Weissman, Myrna M.; Willemsen, Gonneke; Yang, Jingyun; Zhao, Wei; Tiemeier, Henning; Sullivan, Patrick F.

    2017-01-01

    BACKGROUND: The genetics of depression has been explored in genome-wide association studies that focused on either major depressive disorder or depressive symptoms with mostly negative findings. A broad depression phenotype including both phenotypes has not been tested previously using a genome-wide

  5. 78 FR 63479 - Meta-Analyses of Randomized Controlled Clinical Trials (RCTs) for the Evaluation of Risk To...

    Science.gov (United States)

    2013-10-24

    ... with the user fee resources necessary to maintain an efficient review process for human drug and..., including market withdrawal or concluding that a safety concern is not supported by data. As a result, FDA... influence on study selection. b. Lack of or inadequate pre-specification of the meta-analysis hypothesis. c...

  6. Reporting and Handling Missing Outcome Data in Mental Health: A Systematic Review of Cochrane Systematic Reviews and Meta-Analyses

    Science.gov (United States)

    Spineli, Loukia M.; Pandis, Nikolaos; Salanti, Georgia

    2015-01-01

    Objectives: The purpose of the study was to provide empirical evidence about the reporting of methodology to address missing outcome data and the acknowledgement of their impact in Cochrane systematic reviews in the mental health field. Methods: Systematic reviews published in the Cochrane Database of Systematic Reviews after January 1, 2009 by…

  7. Insulin analogues versus human insulin in type 1 diabetes: direct and indirect meta-analyses of efficacy and safety

    Directory of Open Access Journals (Sweden)

    Andréia Cristina Conegero Sanches

    2013-09-01

    Full Text Available All patients with Diabetes Mellitus (DM receive insulin therapy. In this study, we evaluated the efficacy, safety and tolerability of human insulin and insulin analogues. We performed a systematic review of the literature and a meta-analysis according to the Cochrane Collaboration methodology. In the absence of clinical studies comparing insulins, we performed a mixed treatment comparison to establish the differences between the active treatments. We included studies published from 1995 to 2010. HbA1c results, episodes of hypoglycemia and nocturnal hypoglycemia data were extracted and analyzed. Thirty-five randomized clinical trials were selected after examining the abstract and a full text review. These studies included 4,206 patients who received long-acting insulin analogues and 5,733 patients who received short-acting insulin analogues. Pooled data regarding efficacy indicated no significant differences in HbA1c values between glargine or detemir (once daily and NPH insulin. However, a twice-daily dose of detemir produced differences in HbA1c values that favored detemir (-0.14% [95% CI: -0.21 to -0.08]; p<0.0001; I²=0%. Direct and indirect comparisons are consistent and show that there were no significant differences between human insulin and insulin analogues in efficacy or safety. Our results indicate that long- and short-acting insulin analogues offer few clinical advantages over conventional human insulin.

  8. Physical exercise for patients undergoing hematopoietic stem cell transplantation: systematic review and meta-analyses of randomized controlled trials

    NARCIS (Netherlands)

    Haren, I.E.P.M.; Timmerman, H.; Potting, C.M.J.; Blijlevens, N.M.A.; Staal, J.B.; Nijhuis-Van der Sanden, M.W.G.

    2013-01-01

    BACKGROUND: The treatment-related burden for patients undergoing hematopoietic stem cell transplantation (HSCT) may be relieved by physical exercises. PURPOSE: The purpose of this study was to summarize and analyze the evidence provided by randomized controlled trials (RCTs) on physical exercise int

  9. Systematic Reviews and Meta-Analyses of Traditional Chinese Medicine Must Search Chinese Databases to Reduce Language Bias

    Science.gov (United States)

    Wu, Xin-Yin; Tang, Jin-Ling; Mao, Chen; Yuan, Jin-Qiu; Qin, Ying; Chung, Vincent C. H.

    2013-01-01

    Systematic reviews (SRs) that fail to search non-English databases may miss relevant studies and cause selection bias. The bias may be particularly severe in SRs of traditional Chinese medicine (TCM) as most randomized controlled trials (RCT) in TCM are published and accessible only in Chinese. In this study we investigated how often Chinese databases were not searched in SRs of TCM, how many trials were missed, and whether a bias may occur if Chinese databases were not searched. We searched 5 databases in English and 3 in Chinese for RCTs of Chinese herbal medicine for coronary artery disease and found that 96.64% (115/119) eligible studies could be identified only from Chinese databases. In a random sample of 80 Cochrane reviews on TCM, we found that Chinese databases were only searched in 43 or 53.75%, in which almost all the included studies were identified from Chinese databases. We also compared SRs of the same topic and found that they may draw a different conclusion if Chinese databases were not searched. In conclusion, an overwhelmingly high percentage of eligible trials on TCM could only be identified in Chinese databases. Reviewers in TCM are suggested to search Chinese databases to reduce potential selection bias. PMID:24223063

  10. Meta-analyses identify 13 loci associated with age at menopause and highlight DNA repair and immune pathways

    NARCIS (Netherlands)

    Stolk, Lisette; Perry, John R B; Chasman, Daniel I; He, Chunyan; Mangino, Massimo; Sulem, Patrick; Barbalic, Maja; Broer, Linda; Byrne, Enda M; Ernst, Florian; Esko, Tõnu; Franceschini, Nora; Gudbjartsson, Daniel F; Hottenga, Jouke-Jan; Kraft, Peter; McArdle, Patrick F; Porcu, Eleonora; Shin, So-Youn; Smith, Albert V; van Wingerden, Sophie; Zhai, Guangju; Zhuang, Wei V; Albrecht, Eva; Alizadeh, Behrooz Z; Aspelund, Thor; Bandinelli, Stefania; Lauc, Lovorka Barac; Beckmann, Jacques S; Boban, Mladen; Boerwinkle, Eric; Broekmans, Frank J; Burri, Andrea; Campbell, Harry; Chanock, Stephen J; Chen, Constance; Cornelis, Marilyn C; Corre, Tanguy; Coviello, Andrea D; d'Adamo, Pio; Davies, Gail; de Faire, Ulf; de Geus, Eco J C; Deary, Ian J; Dedoussis, George V Z; Deloukas, Panagiotis; Ebrahim, Shah; Eiriksdottir, Gudny; Emilsson, Valur; Eriksson, Johan G; Fauser, Bart C J M; Ferreli, Liana; Ferrucci, Luigi; Fischer, Krista; Folsom, Aaron R; Garcia, Melissa E; Gasparini, Paolo; Gieger, Christian; Glazer, Nicole; Grobbee, Diederick E; Hall, Per; Haller, Toomas; Hankinson, Susan E; Hass, Merli; Hayward, Caroline; Heath, Andrew C; Hofman, Albert; Ingelsson, Erik; Janssens, A Cecile J W; Johnson, Andrew D; Karasik, David; Kardia, Sharon L R; Keyzer, Jules; Kiel, Douglas P; Kolcic, Ivana; Kutalik, Zoltán; Lahti, Jari; Lai, Sandra; Laisk, Triin; Laven, Joop S E; Lawlor, Debbie A; Liu, Jianjun; Lopez, Lorna M; Louwers, Yvonne V; Magnusson, Patrik K E; Marongiu, Mara; Martin, Nicholas G; Klaric, Irena Martinovic; Masciullo, Corrado; McKnight, Barbara; Medland, Sarah E; Melzer, David; Mooser, Vincent; Navarro, Pau; Newman, Anne B; Nyholt, Dale R; Onland-Moret, N Charlotte; Palotie, Aarno; Paré, Guillaume; Parker, Alex N; Pedersen, Nancy L; Peeters, Petra H M; Pistis, Giorgio; Plump, Andrew S; Polasek, Ozren; Pop, Victor J M; Psaty, Bruce M; Räikkönen, Katri; Rehnberg, Emil; Rotter, Jerome I; Rudan, Igor; Sala, Cinzia; Salumets, Andres; Scuteri, Angelo; Singleton, Andrew; Smith, Jennifer A; Snieder, Harold; Soranzo, Nicole; Stacey, Simon N; Starr, John M; Stathopoulou, Maria G; Stirrups, Kathleen; Stolk, Ronald P; Styrkarsdottir, Unnur; Sun, Yan V; Tenesa, Albert; Thorand, Barbara; Toniolo, Daniela; Tryggvadottir, Laufey; Tsui, Kim; Ulivi, Sheila; van Dam, Rob M; van der Schouw, Yvonne T; van Gils, Carla H; van Nierop, Peter; Vink, Jacqueline M; Visscher, Peter M; Voorhuis, Marlies; Waeber, Gérard; Wallaschofski, Henri; Wichmann, H Erich; Widen, Elisabeth; Wijnands-van Gent, Colette J M; Willemsen, Gonneke; Wilson, James F; Wolffenbuttel, Bruce H R; Wright, Alan F; Yerges-Armstrong, Laura M; Zemunik, Tatijana; Zgaga, Lina; Zillikens, M Carola; Zygmunt, Marek; Arnold, Alice M; Boomsma, Dorret I; Buring, Julie E; Crisponi, Laura; Demerath, Ellen W; Gudnason, Vilmundur; Harris, Tamara B; Hu, Frank B; Hunter, David J; Launer, Lenore J; Metspalu, Andres; Montgomery, Grant W; Oostra, Ben A; Ridker, Paul M; Sanna, Serena; Schlessinger, David; Spector, Tim D; Stefansson, Kari; Streeten, Elizabeth A; Thorsteinsdottir, Unnur; Uda, Manuela; Uitterlinden, André G; van Duijn, Cornelia M; Völzke, Henry; Murray, Anna; Murabito, Joanne M; Visser, Jenny A; Lunetta, Kathryn L

    2012-01-01

    To newly identify loci for age at natural menopause, we carried out a meta-analysis of 22 genome-wide association studies (GWAS) in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 loci newly associated with age at natural men

  11. The effect of grinding on the mechanical behavior of Y-TZP ceramics: A systematic review and meta-analyses

    NARCIS (Netherlands)

    Pereira, G.K.R.; Fraga, S.; Montagner, A.F.; Soares, F.Z.M.; Kleverlaan, C.J.; Valandro, L.F.

    2016-01-01

    The aim of this study was to systematically review the literature to assess the effect of grinding on the mechanical properties, structural stability and superficial characteristics of Y-TZP ceramics. The MEDLINE via PubMed and Web of Science (ISI – Web of Knowledge) electronic databases were search

  12. Meta-analyses of vitamin D intake, 25-hydroxyvitamin D status, vitamin D receptor polymorphisms, and colorectal cancer risk

    NARCIS (Netherlands)

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

    2011-01-01

    BACKGROUND: Our objective was to conduct a systematic review and meta-analysis of prospective studies on colorectal cancer (CRC) and vitamin D intake and 25-hydroxyvitamin D status, as part of the World Cancer Research Fund Continuous Update Project. We also aimed at conducting meta-analysis of all

  13. Meta-analyses identify 13 loci associated with age at menopause and highlight DNA repair and immune pathways

    NARCIS (Netherlands)

    L. Stolk (Lisette); J.R.B. Perry (John); D.I. Chasman (Daniel); C. He (Chunyan); M. Mangino (Massimo); P. Sulem (Patrick); M. Barbalic (maja); L. Broer (Linda); E.M. Byrne (Enda); F.D.J. Ernst (Florian); T. Esko (Tõnu); N. Franceschini (Nora); D.F. Gudbjartsson (Daniel); J.J. Hottenga (Jouke Jan); P. Kraft (Peter); P.F. McArdle (Patrick); E. Porcu (Eleonora); S.-Y. Shin; G.D. Smith; S. van Wingerden (Sophie); G. Zhai (Guangju); W.V. Zhuang; E. Albrecht (Eva); B.Z. Alizadeh (Behrooz); T. Aspelund (Thor); S. Bandinelli (Stefania); G. Lauc (Gordan); J.S. Beckmann (Jacques); M. Boban (Mladen); E.A. Boerwinkle (Eric); F.J.M. Broekmans (Frank); A. Burri (Andrea); H. Campbell (Harry); S.J. Chanock (Stephen); C. Chen (Constance); M. Cornelis (Marilyn); T. Corre (Tanguy); A.D. Coviello (Andrea); P. d' Adamo (Pio); G. Davies (Gail); U. de Faire (Ulf); E.J.C. de Geus (Eco); I.J. Deary (Ian); G.V. Dedoussis (George); P. Deloukas (Panagiotis); S. Ebrahim (Shanil); G. Eiriksdottir (Gudny); V. Emilsson (Valur); J.G. Eriksson (Johan); B.C.J.M. Fauser (Bart); L. Ferreli (Liana); L. Ferrucci (Luigi); K. Fischer (Krista); A.R. Folsom (Aaron); M. Garcia (Melissa); P. Gasparini (Paolo); C. Gieger (Christian); N.L. Glazer (Nicole); D.E. Grobbee (Diederick); P. Hall (Per); T. Haller (Toomas); S.E. Hankinson (Susan); M. Hass (Merli); C. Hayward (Caroline); A.C. Heath (Andrew); A. Hofman (Albert); E. Ingelsson (Erik); A.C.J.W. Janssens (Cécile); A.D. Johnson (Andrew); D. Karasik (David); S.L.R. Kardia (Sharon); J.J. de Keyzer (Jules); D.P. Kiel (Douglas); I. Kolcic (Ivana); Z. Kutalik (Zoltán); J. Lahti (Jari); S. Lai (Sandra); T. Laisk (Triin); J.S.E. Laven (Joop); D.A. Lawlor (Debbie); J. Liu (Jianjun); L.M. Lopez (Lorna); Y.V. Louwers (Yvonne); P.K. Magnusson (Patrik); M. Marongiu (Mara); N.G. Martin (Nicholas); I.M. Klaric (Irena Martinovic); C. Masciullo (Corrado); B. McKnight (Barbara); S.E. Medland (Sarah Elizabeth); D. Melzer (David); V. Mooser (Vincent); P. Navarro (Pau); A.B. Newman (Anne); D.R. Nyholt (Dale); N.C. Onland-Moret (Charlotte); A. Palotie (Aarno); G. Paré (Guillaume); A.N. Parker (Alex); N.L. Pedersen (Nancy); P.H.M. Peeters (Petra); G. Pistis (Giorgio); A.S. Plump (Andrew); O. Polasek (Ozren); V. Pop (Victor); B.M. Psaty (Bruce); K. R Currency Signikkönen (Katri); E. Rehnberg (Emil); J.I. Rotter (Jerome); I. Rudan (Igor); C. Sala (Cinzia); A. Salumets (Andres); A. Scuteri (Angelo); A. Singleton (Andrew); J.A. Smith (Jennifer A); H. Snieder (Harold); N. Soranzo (Nicole); S.N. Stacey (Simon); J.M. Starr (John); M.G. Stathopoulou (Maria G); K. Stirrups (Kathy); R.P. Stolk (Ronald); U. Styrkarsdottir (Unnur); Y.V. Sun (Yan); A. Tenesa (Albert); B. Thorand (Barbara); D. Toniolo (Daniela); L. Tryggvadottir (Laufey); K. Tsui (Kim); S. Ulivi (Shelia); R.M. van Dam (Rob); Y.T. van der Schouw (Yvonne); C.H. van Gils (Carla); P.W.M. van Nierop (Peter); J.M. Vink (Jacqueline); P.M. Visscher (Peter); M. Voorhuis (Marlies); G. Waeber (Gérard); H. Wallaschofski (Henri); H.E. Wichmann (Heinz Erich); E. Widen (Elisabeth); C.J.M. Wijnands-Van Gent (Colette J M); G.A.H.M. Willemsen (Gonneke); J.F. Wilson (James); B.H.R. Wolffenbuttel (Bruce); A.F. Wright (Alan); L.M. Yerges-Armstrong (Laura); T. Zemunik (Tatijana); L. Zgaga (Lina); M.C. Zillikens (Carola); M. Zygmunt (Marek); A.M. Arnold (Alice); D.I. Boomsma (Dorret); J.E. Buring (Julie); L. Crisponi (Laura); E.W. Demerath (Ellen); V. Gudnason (Vilmundur); T.B. Harris (Tamara); F.B. Hu (Frank); D. Hunter (David); L.J. Launer (Lenore); A. Metspalu (Andres); G.W. Montgomery (Grant); B.A. Oostra (Ben); P.M. Ridker (Paul); S. Sanna (Serena); D. Schlessinger (David); T.D. Spector (Timothy); J-A. Zwart (John-Anker); E.A. Streeten (Elizabeth); U. Thorsteinsdottir (Unnur); M. Uda (Manuela); A.G. Uitterlinden (André); C.M. van Duijn (Cock); H. Völzke (Henry); A. Murray (Anna); J. Murabito (Joanne); J.A. Visser (Jenny); K.L. Lunetta (Kathryn)

    2012-01-01

    textabstractTo newly identify loci for age at natural menopause, we carried out a meta-analysis of 22 genome-wide association studies (GWAS) in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 loci newly associated with age at

  14. Outcome reporting in randomised controlled trials and meta-analyses of appendicitis treatments in children: a systematic review.

    Science.gov (United States)

    Hall, Nigel J; Kapadia, Mufiza Z; Eaton, Simon; Chan, Winnie W Y; Nickel, Cheri; Pierro, Agostino; Offringa, Martin

    2015-06-17

    Acute appendicitis is the most common surgical emergency in children. Despite this, there is no core outcome set (COS) described for randomised controlled trials (RCTs) in children with appendicitis and hence no consensus regarding outcome selection, definition and reporting. We aimed to identify outcomes currently reported in studies of paediatric appendicitis. Using a defined, sensitive search strategy, we identified RCTs and systematic reviews (SRs) of treatment interventions in children with appendicitis. Included studies were all in English and investigated the effect of one or more treatment interventions in children with acute appendicitis or undergoing appendicectomy for presumed acute appendicitis. Studies were reviewed and data extracted by two reviewers. Primary (if defined) and all other outcomes were recorded and assigned to the core areas 'Death', 'Pathophysiological Manifestations', 'Life Impact', 'Resource Use' and 'Adverse Events', using OMERACT Filter 2.0. A total of 63 studies met the inclusion criteria reporting outcomes from 51 RCTs and nine SRs. Only 25 RCTs and four SRs defined a primary outcome. A total of 115 unique and different outcomes were identified. RCTs reported a median of nine outcomes each (range 1 to 14). The most frequently reported outcomes were wound infection (43 RCTs, nine SRs), intra-peritoneal abscess (41 RCTs, seven SRs) and length of stay (35 RCTs, six SRs) yet all three were reported in just 25 RCTs and five SRs. Common outcomes had multiple different definitions or were frequently not defined. Although outcomes were reported within all core areas, just one RCT and no SR reported outcomes for all core areas. Outcomes assigned to the 'Death' and 'Life Impact' core areas were reported least frequently (in six and 15 RCTs respectively). There is a wide heterogeneity in the selection and definition of outcomes in paediatric appendicitis, and little overlap in outcomes used across studies. A paucity of studies report patient

  15. Associations between diet-related diseases and impaired physiological mechanisms: a holistic approach based on meta-analyses to identify targets for preventive nutrition.

    Science.gov (United States)

    Fardet, Anthony; Boirie, Yves

    2013-10-01

    In nutrition research, analyzing the relationship between a diet-related chronic disease and impaired metabolism is a common reductionist approach. Meta-analyses have enabled quantification of these relationships. There is, however, a need for more holistic approaches to determine the sequence of connections between diseases and associated physiological mechanisms. The objective of this exhaustive review was to collect scientific evidence – with priority given to quantitative reviews – published between 1950 and 2011 to assess the relationships between major diet-related chronic diseases and deregulated mechanisms. The results revealed that diabetes and obesity are the key diseases that lead to all other diet-related chronic diseases, while cancer, cardiovascular disease, skeletal disease, and sarcopenia are endpoint diseases. Liver disease, kidney disease, digestive disease, and mental illness are consequences as well as causes of other diet-related chronic diseases. All diseases have multifactorial causes, and most result from decreased antioxidant status, acid-base imbalance, increased inflammatory status, impaired carbohydrate/lipid/one-carbon metabolism, impaired functioning of neurons and DNA transcription, hypertension, and/or modified digestive microflora. Nutritional strategies that focus on the prevention of obesity and diabetes should be prioritized in order to reduce the prevalence of other major chronic diseases.

  16. Perceiving emotional expressions in others: Activation likelihood estimation meta-analyses of explicit evaluation, passive perception and incidental perception of emotions.

    Science.gov (United States)

    Dricu, Mihai; Frühholz, Sascha

    2016-12-01

    We conducted a series of activation likelihood estimation (ALE) meta-analyses to determine the commonalities and distinctions between separate levels of emotion perception, namely incidental perception, passive perception, and explicit evaluation of emotional expressions. Pooling together more than 180 neuroimaging experiments using facial, vocal or body expressions, our results are threefold. First, explicitly evaluating the emotions of others recruits brain regions associated with the sensory processing of expressions, such as the inferior occipital gyrus, middle fusiform gyrus and the superior temporal gyrus, and brain regions involved in low-level and high-level mindreading, namely the posterior superior temporal sulcus, the inferior frontal cortex and dorsomedial frontal cortex. Second, we show that only the sensory regions were also consistently active during the passive perception of emotional expressions. Third, we show that the brain regions involved in mindreading were active during the explicit evaluation of both facial and vocal expressions. We discuss these results in light of the existing literature and conclude by proposing a cognitive model for perceiving and evaluating the emotions of others. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Rate of change in carotid intima-media thickness and vascular events: meta-analyses can not solve all the issues. A point of view.

    Science.gov (United States)

    Bots, Michiel L; Taylor, Allen J; Kastelein, John J P; Peters, Sanne A E; den Ruijter, Hester M; Tegeler, Charles H; Baldassarre, Damiano; Stein, James H; O'Leary, Daniel H; Revkin, James H; Grobbee, Diederick E

    2012-09-01

    Whether a change in the rate of carotid intima-media thickness (CIMT) over time that is induced by a pharmaceutical intervention can be directly translated into change in future cardiovascular disease risk is an important issue. As this biomarker is increasingly used as primary outcome in many trials of the evaluation of novel cardiovascular treatments, this has become an important topic in cardiovascular drug development. Two recent meta-analyses using aggregated data from publication have attempted to address the issue. In our view both analyses suffer from considerable flaws. Flaws include the misuse of the concept of the atherosclerosis, pooling of trials carried out with treatments of heterogeneous efficacy and in patients, who had very different risk profiles; pooling of measurements from a wide variety of methodologies that shared a common name, 'CIMT'; lack of power for detecting relationships using meta-regression techniques, and lastly, the ecologic fallacy. In this article, we discuss the concerns in more detail and offer strategies to get a valid answer on whether therapy-induced change in CIMT indeed relates to change in vascular risk.

  18. Do Fructose-Containing Sugars Lead to Adverse Health Consequences? Results of Recent Systematic Reviews and Meta-analyses123

    OpenAIRE

    Ha, Vanessa; Cozma, Adrian I; Choo, Vivian LW; Mejia, Sonia Blanco; de Souza, Russell J; Sievenpiper, John L.

    2015-01-01

    Sugars have replaced fat as the dominant public health nutrition concern. A fructose-centric view of cardiometabolic disease has emerged whereby fructose-containing sugars are thought to have deleterious effects on body weight, fasting and postprandial blood lipids, glycemia, blood pressure, uric acid, and markers of nonalcoholic fatty liver disease. Long-term prospective cohort studies have not supported these associations when assessing the relation between total fructose-containing sugars ...

  19. Resurrecting Brinley Plots for a Novel Use: Meta-Analyses of Functional Brain Imaging Data in Older Adults

    Directory of Open Access Journals (Sweden)

    Ann M. Peiffer

    2008-01-01

    Full Text Available By plotting response times of young and older adults across a variety of tasks, Brinley spurred investigation and debate into the theory of general cognitive slowing. Though controversial, Brinley plots can assess between-task differences, the impact of increasing task demand, and the relationship between responses in two groups of subjects. Since a relationship exists between response times and the blood-oxygen level dependent (BOLD signal of functional MRI (fMRI, Brinley's plotting method could be applied as a meta-analysis tool in fMRI studies of aging. Here, fledgling “Peiffer plots” are discussed for their potential impact on understanding general cognitive brain activity in aging. Preliminary results suggest that general cognitive slowing may be localized at the sensorimotor transformation in the precentral gyrus. Although this meta-analysis method is naturally used with imaging studies of aging, theoretically it may be applied to other study pairs (e.g., schizophrenic versus normal or imaging datasets (e.g., PET.

  20. Meta-Analyses of QTLs Associated with Protein and Oil Contents and Compositions in Soybean [Glycine max (L.) Merr.] Seed.

    Science.gov (United States)

    Van, Kyujung; McHale, Leah K

    2017-06-01

    Soybean [Glycine max (L.) Merr.] is a valuable and nutritious crop in part due to the high protein meal and vegetable oil produced from its seed. Soybean producers desire cultivars with both elevated seed protein and oil concentrations as well as specific amino acid and fatty acid profiles. Numerous studies have identified quantitative trait loci (QTLs) associated with seed composition traits, but validation of these QTLs has rarely been carried out. In this study, we have collected information, including genetic location and additive effects, on each QTL for seed contents of protein and oil, as well as amino acid and fatty acid compositions from over 80 studies. Using BioMercator V. 4.2, a meta-QTL analysis was performed with genetic information comprised of 175 QTLs for protein, 205 QTLs for oil, 156 QTLs for amino acids, and 113 QTLs for fatty acids. A total of 55 meta-QTL for seed composition were detected on 6 out of 20 chromosomes. Meta-QTL possessed narrower confidence intervals than the original QTL and candidate genes were identified within each meta-QTL. These candidate genes elucidate potential natural genetic variation in genes contributing to protein and oil biosynthesis and accumulation, providing meaningful information to further soybean breeding programs.

  1. Preterm birth and low birth weight among in vitro fertilization singletons: a systematic review and meta-analyses.

    Science.gov (United States)

    McDonald, Sarah D; Han, Zhen; Mulla, Sohail; Murphy, Kellie E; Beyene, Joseph; Ohlsson, Arne

    2009-10-01

    Our objective was to determine the risks of preterm birth (PTB) and low birth weight (LBW) in singletons conceived through in vitro fertilization (IVF)+/-intracytoplasmic sperm injection (ICSI) compared to spontaneously conceived singletons after matching or controlling for at least maternal age. The MOOSE guidelines for meta-analysis of observational studies were followed. Medline and Embase were searched using comprehensive search strategies. Bibliographies of identified articles were reviewed. English language studies examining LBW or PTB in singletons conceived by IVF or IVF/intracytoplasmic sperm injection, compared with spontaneously conceived singletons, that matched or controlled for at least maternal age. Two reviewers independently assessed titles, abstracts, full articles and study quality and extracted data. Dichotomous data were meta-analyzed using relative risks (RR) as measures of effect size with a random effects model and for continuous data weighted mean difference was calculated. Seventeen studies were included with 31,032 singletons conceived through IVF (+/-ICSI) and 81,119 spontaneously conceived singletons. After matching or controlling for maternal age and often other factors, compared to spontaneously conceived singletons, IVF singletons had increased risks of our two primary outcomes, PTB (RR 1.84, 95% CI 1.54, 2.21) and LBW (<2500 g, RR 1.60, 95% CI 1.29, 1.98). Singletons conceived through IVF or IVF/ICSI were at increased risk for late PTB (32-36 weeks, RR 1.52, 95% CI 1.01, 2.30), moderate PTB <32-33 weeks (RR 2.27, 95% CI 1.73, 2.97), very LBW (<1500 g, RR 2.65, 95% CI 1.83, 3.84), and intrauterine growth restriction (RR 1.45, 95% CI 1.04, 2.00), lower birth weights (-97 g, 95% CI -161 g, -33 g) and shorter mean gestations (-0.6 weeks, 95% CI -0.9 weeks, -0.4 weeks). In conclusion, IVF singletons have significantly increased risks of PTB, LBW and other adverse perinatal outcomes compared to spontaneously conceived singletons after

  2. Extending DerSimonian and Laird's methodology to perform network meta-analyses with random inconsistency effects.

    Science.gov (United States)

    Jackson, Dan; Law, Martin; Barrett, Jessica K; Turner, Rebecca; Higgins, Julian P T; Salanti, Georgia; White, Ian R

    2016-03-15

    Network meta-analysis is becoming more popular as a way to compare multiple treatments simultaneously. Here, we develop a new estimation method for fitting models for network meta-analysis with random inconsistency effects. This method is an extension of the procedure originally proposed by DerSimonian and Laird. Our methodology allows for inconsistency within the network. The proposed procedure is semi-parametric, non-iterative, fast and highly accessible to applied researchers. The methodology is found to perform satisfactorily in a simulation study provided that the sample size is large enough and the extent of the inconsistency is not very severe. We apply our approach to two real examples.

  3. Treatment of bacteremia by vancomycin-resistant Enterococcus with daptomycin versus linezolid: a systematic review and meta-analyses

    Directory of Open Access Journals (Sweden)

    Caicedo-Ochoa, Edgar Yaset

    2017-01-01

    Full Text Available Introduction: Second-line drugs such as linezolid and daptomycin are used for treatment of vancomycin-resistant Enterococcus (VRE infections. Objective: A systematic review to evaluate treatment of VRE bacteremia with linezolid versus daptomycin. Methods: A search was done in the databases of Pubmed, Embase, Scopus, ScienceDirect, CENTRAL, Lilacs and Google Scholar to identify studies comparing treatment with daptomycin or linezolid of patients infected by VRE up to July 2015. Result: Only 15 studies were included of a total of 1.307 records. There were no differences between daptomycin and linezolid with respect to mortality at 30 days. Microbiological cure was better with daptomycin (OR: 0.64; 95 % CI: 0.45-0.92, whereas there was no difference between the two antibiotics with respect to clinical cure, need to ICU admission, and the occurrence of adverse effects such as thrombocytopenia, neutropenia and renal failure. Conclusions: No significant differences were observed between daptomycin and linezolid in reference to mortality of patients infected with VRE, although daptomycin treatment produced a faster microbiological cure.

  4. Meta-analyses identify 13 novel loci associated with age at menopause and highlights DNA repair and immune pathways

    Science.gov (United States)

    Stolk, Lisette; Perry, John RB; Chasman, Daniel I; He, Chunyan; Mangino, Massimo; Sulem, Patrick; Barbalic, Maja; Broer, Linda; Byrne, Enda M; Ernst, Florian; Esko, Tõnu; Franceschini, Nora; Gudbjartsson, Daniel F; Hottenga, Jouke-Jan; Kraft, Peter; McArdle, Patick F; Porcu, Eleonora; Shin, So-Youn; Smith, Albert V; van Wingerden, Sophie; Zhai, Guangju; Zhuang, Wei V; Albrecht, Eva; Alizadeh, Behrooz Z; Aspelund, Thor; Bandinelli, Stefania; Lauc, Lovorka Barac; Beckmann, Jacques S; Boban, Mladen; Boerwinkle, Eric; Broekmans, Frank J; Burri, Andrea; Campbell, Harry; Chanock, Stephen J; Chen, Constance; Cornelis, Marilyn C; Corre, Tanguy; Coviello, Andrea D; d’Adamo, Pio; Davies, Gail; de Faire, Ulf; de Geus, Eco JC; Deary, Ian J; Dedoussis, George VZ; Deloukas, Panagiotis; Ebrahim, Shah; Eiriksdottir, Gudny; Emilsson, Valur; Eriksson, Johan G; Fauser, Bart CJM; Ferreli, Liana; Ferrucci, Luigi; Fischer, Krista; Folsom, Aaron R; Garcia, Melissa E; Gasparini, Paolo; Gieger, Christian; Glazer, Nicole; Grobbee, Diederick E; Hall, Per; Haller, Toomas; Hankinson, Susan E; Hass, Merli; Hayward, Caroline; Heath, Andrew C; Hofman, Albert; Ingelsson, Erik; Janssens, A Cecile JW; Johnson, Andrew D; Karasik, David; Kardia, Sharon LR; Keyzer, Jules; Kiel, Douglas P; Kolcic, Ivana; Kutalik, Zoltán; Lahti, Jari; Lai, Sandra; Laisk, Triin; Laven, Joop SE; Lawlor, Debbie A; Liu, Jianjun; Lopez, Lorna M; Louwers, Yvonne V; Magnusson, Patrik KE; Marongiu, Mara; Martin, Nicholas G; Klaric, Irena Martinovic; Masciullo, Corrado; McKnight, Barbara; Medland, Sarah E; Melzer, David; Mooser, Vincent; Navarro, Pau; Newman, Anne B; Nyholt, Dale R; Onland-Moret, N. Charlotte; Palotie, Aarno; Paré, Guillaume; Parker, Alex N; Pedersen, Nancy L; Peeters, Petra HM; Pistis, Giorgio; Plump, Andrew S; Polasek, Ozren; Pop, Victor JM; Psaty, Bruce M; Räikkönen, Katri; Rehnberg, Emil; Rotter, Jerome I; Rudan, Igor; Sala, Cinzia; Salumets, Andres; Scuteri, Angelo; Singleton, Andrew; Smith, Jennifer A; Snieder, Harold; Soranzo, Nicole; Stacey, Simon N; Starr, John M; Stathopoulou, Maria G; Stirrups, Kathleen; Stolk, Ronald P; Styrkarsdottir, Unnur; Sun, Yan V; Tenesa, Albert; Thorand, Barbara; Toniolo, Daniela; Tryggvadottir, Laufey; Tsui, Kim; Ulivi, Sheila; van Dam, Rob M; van der Schouw, Yvonne T; van Gils, Carla H; van Nierop, Peter; Vink, Jacqueline M; Visscher, Peter M; Voorhuis, Marlies; Waeber, Gérard; Wallaschofski, Henri; Wichmann, H Erich; Widen, Elisabeth; Gent, Colette JM Wijnands-van; Willemsen, Gonneke; Wilson, James F; Wolffenbuttel, Bruce HR; Wright, Alan F; Yerges-Armstrong, Laura M; Zemunik, Tatijana; Zgaga, Lina; Zillikens, M. Carola; Zygmunt, Marek; Arnold, Alice M; Boomsma, Dorret I; Buring, Julie E.; Crisponi, Laura; Demerath, Ellen W; Gudnason, Vilmundur; Harris, Tamara B; Hu, Frank B; Hunter, David J; Launer, Lenore J; Metspalu, Andres; Montgomery, Grant W; Oostra, Ben A; Ridker, Paul M; Sanna, Serena; Schlessinger, David; Spector, Tim D; Stefansson, Kari; Streeten, Elizabeth A; Thorsteinsdottir, Unnur; Uda, Manuela; Uitterlinden, André G; van Duijn, Cornelia M; Völzke, Henry; Murray, Anna; Murabito, Joanne M; Visser, Jenny A; Lunetta, Kathryn L

    2011-01-01

    To identify novel loci for age at natural menopause, we performed a meta-analysis of 22 genome-wide association studies in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 new age at natural menopause loci (P < 5 × 10−8). The new loci included genes implicated in DNA repair (EXO1, HELQ, UIMC1, FAM175A, FANCI, TLK1, POLG, PRIM1) and immune function (IL11, NLRP11, BAT2). Gene-set enrichment pathway analyses using the full GWAS dataset identified exodeoxyribonuclease, NFκB signalling and mitochondrial dysfunction as biological processes related to timing of menopause. PMID:22267201

  5. Psychosocial versus physiological stress - Meta-analyses on deactivations and activations of the neural correlates of stress reactions.

    Science.gov (United States)

    Kogler, Lydia; Müller, Veronika I; Chang, Amy; Eickhoff, Simon B; Fox, Peter T; Gur, Ruben C; Derntl, Birgit

    2015-10-01

    Stress is present in everyday life in various forms and situations. Two stressors frequently investigated are physiological and psychosocial stress. Besides similar subjective and hormonal responses, it has been suggested that they also share common neural substrates. The current study used activation-likelihood-estimation meta-analysis to test this assumption by integrating results of previous neuroimaging studies on stress processing. Reported results are cluster-level FWE corrected. The inferior frontal gyrus (IFG) and the anterior insula (AI) were the only regions that demonstrated overlapping activation for both stressors. Analysis of physiological stress showed consistent activation of cognitive and affective components of pain processing such as the insula, striatum, or the middle cingulate cortex. Contrarily, analysis across psychosocial stress revealed consistent activation of the right superior temporal gyrus and deactivation of the striatum. Notably, parts of the striatum appeared to be functionally specified: the dorsal striatum was activated in physiological stress, whereas the ventral striatum was deactivated in psychosocial stress. Additional functional connectivity and decoding analyses further characterized this functional heterogeneity and revealed higher associations of the dorsal striatum with motor regions and of the ventral striatum with reward processing. Based on our meta-analytic approach, activation of the IFG and the AI seems to indicate a global neural stress reaction. While physiological stress activates a motoric fight-or-flight reaction, during psychosocial stress attention is shifted towards emotion regulation and goal-directed behavior, and reward processing is reduced. Our results show the significance of differentiating physiological and psychosocial stress in neural engagement. Furthermore, the assessment of deactivations in addition to activations in stress research is highly recommended.

  6. Meta-Analyses of Microarray Datasets Identifies ANO1 and FADD as Prognostic Markers of Head and Neck Cancer.

    Directory of Open Access Journals (Sweden)

    Ram Bhupal Reddy

    Full Text Available The head and neck squamous cell carcinoma (HNSCC transcriptome has been profiled extensively, nevertheless, identifying biomarkers that are clinically relevant and thereby with translational benefit, has been a major challenge. The objective of this study was to use a meta-analysis based approach to catalog candidate biomarkers with high potential for clinical application in HNSCC. Data from publically available microarray series (N = 20 profiled using Agilent (4X44K G4112F and Affymetrix (HGU133A, U133A_2, U133Plus 2 platforms was downloaded and analyzed in a platform/chip-specific manner (GeneSpring software v12.5, Agilent, USA. Principal Component Analysis (PCA and clustering analysis was carried out iteratively for segregating outliers; 140 normal and 277 tumor samples from 15 series were included in the final analysis. The analyses identified 181 differentially expressed, concordant and statistically significant genes; STRING analysis revealed interactions between 122 of them, with two major gene clusters connected by multiple nodes (MYC, FOS and HSPA4. Validation in the HNSCC-specific database (N = 528 in The Cancer Genome Atlas (TCGA identified a panel (ECT2, ANO1, TP63, FADD, EXT1, NCBP2 that was altered in 30% of the samples. Validation in treatment naïve (Group I; N = 12 and post treatment (Group II; N = 12 patients identified 8 genes significantly associated with the disease (Area under curve>0.6. Correlation with recurrence/re-recurrence showed ANO1 had highest efficacy (sensitivity: 0.8, specificity: 0.6 to predict failure in Group I. UBE2V2, PLAC8, FADD and TTK showed high sensitivity (1.00 in Group I while UBE2V2 and CRYM were highly sensitive (>0.8 in predicting re-recurrence in Group II. Further, TCGA analysis showed that ANO1 and FADD, located at 11q13, were co-expressed at transcript level and significantly associated with overall and disease-free survival (p<0.05. The meta-analysis approach adopted in this study has

  7. Acceptance and commitment therapy - Do we know enough? Cumulative and sequential meta-analyses of randomized controlled trials.

    Science.gov (United States)

    Hacker, Thomas; Stone, Paul; MacBeth, Angus

    2016-01-15

    Acceptance and Commitment Therapy (ACT) has accrued a substantial evidence base. Recent systematic and meta-analytic reviews suggest that ACT is effective compared to control conditions. However, these reviews appraise the efficacy of ACT across a broad range of presenting problems, rather than addressing specific common mental health difficulties. Focussing on depression and anxiety we performed a meta-analysis of trials of ACT. We incorporated sequential meta-analysis (SMA) techniques to critically appraise the sufficiency of the existing evidence base. Findings suggest that ACT demonstrates at least moderate group and pre-post effects for symptom reductions for both anxiety and depression. However using SMA findings are more qualified. There is currently insufficient evidence to confidently conclude that ACT for anxiety is efficacious when compared to active control conditions or as primary treatment for anxiety. Similarly, using SMA, there is currently insufficient evidence to suggest a moderate efficacy of ACT for depression compared to active control conditions. To stimulate further research we offer specific estimates of additional numbers of participants required to reach sufficiency to help inform future studies. We also discuss the appropriate strategies for future research into ACT for anxiety given the current evidence suggests no differential efficacy of ACT in the treatment of anxiety compared to active control conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Clinical effectiveness and safety of montelukast in asthma. What are the conclusions from clinical trials and meta-analyses?

    Directory of Open Access Journals (Sweden)

    Hon KLE

    2014-06-01

    Full Text Available Kam Lun Ellis Hon,1 Ting Fan Leung,1 Alexander KC Leung21Department of Paediatrics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong; 2Department of Pediatrics, The University of Calgary, Calgary, AB, CanadaAbstract: Asthma is a common childhood atopic disease associated with chronicity and impaired quality of life. As there is no cure for this disease, treatment relies on avoidance of triggers such as food and aeroallergens, the use of inhaled bronchodilators/corticosteroids and antiallergic or immunomodulating therapies. Inhaled corticosteroids (ICSs and bronchodilators have been the mainstay. However, in Asia, myths and fallacies regarding Western medicine and corticosteroids are prevalent and lead to nonadherence to treatment. Also, use of traditional and proprietary herbal medicines is popular. In the past decades, a novel class of nonsteroidal immunomodulating montelukasts has become available. This article reviews the evidence for the effectiveness and clinical efficacy of these medications. A number of randomized and controlled trials have been performed over the years. The majority of studies confirm the usefulness of montelukast as monotherapy and add-on therapy to ICS in mild to moderate childhood asthma across all age groups. ICSs are generally superior to montelukasts for asthma management. However, montelukast has a place in the treatment of young children with viral-triggered wheezing diseases, exercise-induced asthma, and in children whose parents are steroid-phobic and find ICS unacceptable.Keywords: cysteinyl leukotriene receptor antagonist, inhaled corticosteroid, randomized control trial, meta analysis

  9. Standardised mindfulness-based interventions in healthcare: an overview of systematic reviews and meta-analyses of RCTs.

    Directory of Open Access Journals (Sweden)

    Rinske A Gotink

    Full Text Available Mindfulness-based therapies are being used in a wide range of common chronic conditions in both treatment and prevention despite lack of consensus about their effectiveness in different patient categories.To systematically review the evidence of effectiveness MBSR and MBCT in different patient categories.A systematic review and meta-analysis of systematic reviews of RCTs, using the standardized MBSR or MBCT programs. We used PRISMA guidelines to assess the quality of the included reviews and performed a random effects meta-analysis with main outcome measure Cohen's d. All types of participants were considered.The search produced 187 reviews: 23 were included, covering 115 unique RCTs and 8,683 unique individuals with various conditions. Compared to wait list control and compared to treatment as usual, MBSR and MBCT significantly improved depressive symptoms (d=0.37; 95%CI 0.28 to 0.45, based on 5 reviews, N=2814, anxiety (d=0.49; 95%CI 0.37 to 0.61, based on 4 reviews, N=2525, stress (d=0.51; 95%CI 0.36 to 0.67, based on 2 reviews, N=1570, quality of life (d=0.39; 95%CI 0.08 to 0.70, based on 2 reviews, N=511 and physical functioning (d=0.27; 95%CI 0.12 to 0.42, based on 3 reviews, N=1015. Limitations include heterogeneity within patient categories, risk of publication bias and limited long-term follow-up in several studies.The evidence supports the use of MBSR and MBCT to alleviate symptoms, both mental and physical, in the adjunct treatment of cancer, cardiovascular disease, chronic pain, depression, anxiety disorders and in prevention in healthy adults and children.

  10. Treatments for acute bipolar depression: meta-analyses of placebo-controlled, monotherapy trials of anticonvulsants, lithium and antipsychotics.

    Science.gov (United States)

    Selle, V; Schalkwijk, S; Vázquez, G H; Baldessarini, R J

    2014-03-01

    Optimal treatments for bipolar depression, and the relative value of specific drugs for that purpose, remain uncertain, including agents other than antidepressants. We searched for reports of placebo-controlled, monotherapy trials of mood-stabilizing anticonvulsants, second-generation antipsychotics, or lithium for acute major depressive episodes in patients diagnosed with type I or II bipolar disorder and applied random-effects meta-analysis to evaluate their efficacy, comparing outcomes based on standardized mean drug-placebo differences (SMD) in improvement, relative response rates (RR), and number-needed-to-treat (NNT). We identified 24 trials of 10 treatments (lasting 7.5 weeks, with ≥ 50 collaborating sites/trial) that met eligibility criteria: lamotrigine (5 trials), quetiapine (5), valproate (4), 2 each for aripiprazole, olanzapine, ziprasidone, and 1 each for carbamazepine, lithium, lurasidone, and olanzapine-fluoxetine. Overall, pooled drug-over-placebo responder-rate superiority (RR) was moderate (29% [CI: 19-40%]), and NNT was 8.2 (CI: 6.4-11). By SMD, apparent efficacy ranked: olanzapine + fluoxetine ≥ valproate > quetiapine > lurasidone > olanzapine, aripiprazole, and carbamazepine; ziprasidone was ineffective, and lithium remains inadequately studied. Notably, drugs were superior to placebo in only 11/24 trials (5/5 with quetiapine, 2/4 with valproate), and only lamotrigine, quetiapine and valproate had > 2 trials. Treatment-associated mania-like reactions were uncommon (drugs: 3.7%; placebo: 4.7%). Controlled trials of non-antidepressant treatments for bipolar depression remain scarce, but findings with olanzapine-fluoxetine, lurasidone, quetiapine, and perhaps carbamazepine and valproate were encouraging; lithium requires adequate testing. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Metanálisis: Relación entre factores psicosociales en el trabajo y absentismo laboral Meta-analyses: Relation between psychosocial factors in the work and labour absenteeism

    Directory of Open Access Journals (Sweden)

    Josep Mª Molina Aragonés

    2010-09-01

    era relevante para ser incluidos. Control: El gráfico Forest (Fig. 2 muestra el resultado del metanálisis: el riesgo relativo de sufrir un episodio de absentismo es estadísticamente significativo, con un valor de 1,36 (CI: 1,02-1,82 (Tabla 2. Demanda: El riesgo de sufrir un episodio de absentismo no es valorable, con un valor de 1,01 (IC: 0,91-1,11. (Tabla 3. Si bien la demanda, como dimensión propia de estos factores psicosociales, no parece una variable relacionada o que influencie el absentismo laboral, el control si que se encuentra asociado a este, de manera reiterada y consistente.Introduction: In accordance with the model of demand-control, the overhead labour demand, the low control on itself and in a very special way the combination of both, it would suppose an important risk for health. The balance between demand and control depends, just as this model, on the organization of the work and not on the individual characteristics of each person, although, of course, the influence of the working psychosocial environment can be, and in fact is, moderated by the characteristics of the individual answer. Objectives: The study's objective was to analyse in a systematic way those studies that related the effects over absenteeism that the psychosocial factors have constituted in the enterprises, using as a main element of assessment, the model of demand-control of Karasek, and to make a meta-analyses to evaluated the relation between both of them. Methods: There were identified publications from the electronics data bases Medline (2004 to July 2009, Embase (2004 to March 2009, PsycInfo (2004 to July 2009 and in the Bookshop Cochrane (2004 to July 2009, without restrictions motivated by language. The keyboards used were absenteeism, sickness absence, psychosocial, occupational and combinations of them that were chosen initially by its inclusion on the meta-analyses. Additionally the appointments mentioned were reviewed in the selected originals to detect some other

  12. The totally extraperitoneal method versus Lichtenstein's technique for inguinal hernia repair: a systematic review with meta-analyses and trial sequential analyses of randomized clinical trials.

    Directory of Open Access Journals (Sweden)

    G G Koning

    Full Text Available BACKGROUND: Lichtenstein's technique is considered the reference technique for inguinal hernia repair. Recent trials suggest that the totally extraperitoneal (TEP technique may lead to reduced proportions of chronic pain. A systematic review evaluating the benefits and harms of the TEP compared with Lichtenstein's technique is needed. METHODOLOGY/PRINCIPAL FINDINGS: The review was performed according to the 'Cochrane Handbook for Systematic Reviews'. Searches were conducted until January 2012. Patients with primary uni- or bilateral inguinal hernias were included. Only trials randomising patients to TEP and Lichtenstein were included. Bias evaluation and trial sequential analysis (TSA were performed. The error matrix was constructed to minimise the risk of systematic and random errors. Thirteen trials randomized 5404 patients. There was no significant effect of the TEP compared with the Lichtenstein on the number of patients with chronic pain in a random-effects model risk ratio (RR 0.80; 95% confidence interval (CI 0.61 to 1.04; p = 0.09. There was also no significant effect on number of patients with recurrences in a random-effects model (RR 1.41; 95% CI 0.72 to 2.78; p = 0.32 and the TEP technique may or may not be associated with less severe adverse events (random-effects model RR 0.91; 95% CI 0.73 to 1.12; p = 0.37. TSA showed that the required information size was far from being reached for patient important outcomes. CONCLUSIONS/SIGNIFICANCE: TEP versus Lichtenstein for inguinal hernia repair has been evaluated by 13 trials with high risk of bias. The review with meta-analyses, TSA and error matrix approach shows no conclusive evidence of a difference between TEP and Lichtenstein on the primary outcomes chronic pain, recurrences, and severe adverse events.

  13. What guidance are researchers given on how to present network meta-analyses to end-users such as policymakers and clinicians? A systematic review.

    Directory of Open Access Journals (Sweden)

    Shannon M Sullivan

    Full Text Available INTRODUCTION: Network meta-analyses (NMAs are complex methodological approaches that may be challenging for non-technical end-users, such as policymakers and clinicians, to understand. Consideration should be given to identifying optimal approaches to presenting NMAs that help clarify analyses. It is unclear what guidance researchers currently have on how to present and tailor NMAs to different end-users. METHODS: A systematic review of NMA guidelines was conducted to identify guidance on how to present NMAs. Electronic databases and supplementary sources were searched for NMA guidelines. Presentation format details related to sample formats, target audiences, data sources, analysis methods and results were extracted and frequencies tabulated. Guideline quality was assessed following criteria developed for clinical practice guidelines. RESULTS: Seven guidelines were included. Current guidelines focus on how to conduct NMAs but provide limited guidance to researchers on how to best present analyses to different end-users. None of the guidelines provided reporting templates. Few guidelines provided advice on tailoring presentations to different end-users, such as policymakers. Available guidance on presentation formats focused on evidence networks, characteristics of individual trials, comparisons between direct and indirect estimates and assumptions of heterogeneity and/or inconsistency. Some guidelines also provided examples of figures and tables that could be used to present information. CONCLUSIONS: Limited guidance exists for researchers on how best to present NMAs in an accessible format, especially for non-technical end-users such as policymakers and clinicians. NMA guidelines may require further integration with end-users' needs, when NMAs are used to support healthcare policy and practice decisions. Developing presentation formats that enhance understanding and accessibility of NMAs could also enhance the transparency and legitimacy of

  14. Are we hammering square pegs into round holes? An investigation of the meta-analyses of reading research with students who are d/Deaf or hard of hearing and students who are hearing.

    Science.gov (United States)

    Wang, Ye; Williams, Cheri

    2014-01-01

    In a qualitative meta-analysis, the researchers systematically reviewed qualitative and quantitative meta-analyses on reading research with PK-12 students published after the 2000 National Reading Panel (NRP) report. Eleven qualitative and 39 quantitative meta-analyses were reviewed examining reading research with typically developing hearing students, special education hearing students (including English Language Learners), and d/Deaf or hard of hearing (d/Dhh) students. Generally, the meta-analysis yielded findings similar to and corroborative of the NRP's. Contradictory results (e.g., regarding the role of rhyme awareness in reading outcomes) most often resulted from differing definitions of interventions and their measurements. The analysis provided evidence of several instructional approaches that support reading development. On the basis of the qualitative similarity hypothesis (Paul, 2010, 2012; Paul & Lee, 2010; Paul & Wang, 2012; Paul, Wang, & Williams, 2013), the researchers argue that these instructional strategies also should effectively support d/Dhh children's reading development.

  15. The Treatment of Restless Legs Syndrome and Periodic Limb Movement Disorder in Adults—An Update for 2012: Practice Parameters with an Evidence-Based Systematic Review and Meta-Analyses: An American Academy of Sleep Medicine Clinical Practice Guideline

    OpenAIRE

    Aurora, R. Nisha; Kristo, David A.; Bista, Sabin R.; Rowley, James A.; Zak, Rochelle S.; Casey, Kenneth R.; Lamm, Carin I.; Tracy, Sharon L.; Rosenberg, Richard S.

    2012-01-01

    A systematic literature review and meta-analyses (where appropriate) were performed to update the previous AASM practice parameters on the treatments, both dopaminergic and other, of RLS and PLMD. A considerable amount of literature has been published since these previous reviews were performed, necessitating an update of the corresponding practice parameters. Therapies with a STANDARD level of recommendation include pramipexole and ropinirole. Therapies with a GUIDELINE level of recommendati...

  16. SiPaGene: A new repository for instant online retrieval, sharing and meta-analyses of GeneChip® expression data

    Directory of Open Access Journals (Sweden)

    Burmester Gerd-R

    2009-03-01

    repository and a high quality tool for primary analysis of GeneChips. It exploits the MAS5.0/GCOS pairwise comparison algorithm, enables restricted access and user specific sharing. It does not aim for a complete representation of all public arrays but for high quality analysis with stepwise integration of reference signatures for detailed meta-analyses. Development of additional tools like functional annotation networks based on expression information will be future steps towards a systematic biological analysis of expression profiles.

  17. 生存资料的二次研究系列之四:预后相关系统评价/Meta分析的文献计量学研究%Bibliometric analysis on prognosis-related systematic reviews/Meta-analyses

    Institute of Scientific and Technical Information of China (English)

    孟详喻; 方程; 李妙竹; 田国祥; 曾宪涛

    2016-01-01

    预后指标在医学研究及临床实践中都具有重要意义。预后相关的系统评价/Meta分析对预后方面的研究资料进行评价、汇总以形成能用于指导临床实践的高质量证据。为了探索预后相关系统评价/Meta分析当前在全球范围的研究现状,本文通过检索Scopus数据库获得2006~2015年间发表的预后相关的系统评价/Meta分析文献,利用R软件、tm程序包、ggplot2程序包以及VOSviewer软件进行文献计量学分析、简单的文本挖掘及相关可视化展示。%Prognostic indices are of major importance and significance in medical research and clinical practice. Prognosis-related systematic reviews/Meta-analyses evaluate and summarize relevant study findings, generating high quality clinically applicable evidence. In order to examine the current scientific landscape of prognosis-related systematic reviews/Meta-analyses worldwide, we performed this bibliometric analysis with text mining and visualization. Relevant literature published during 2006-2015 was used as the source material, which was obtained by searching the Scopus database. The R software, tm package, ggplot2 package and VOSviewer were used as software tools.

  18. Large scale meta-analyses of fasting plasma glucose raising variants in GCK, GCKR, MTNR1B and G6PC2 and their impacts on type 2 diabetes mellitus risk.

    Directory of Open Access Journals (Sweden)

    Haoran Wang

    Full Text Available BACKGROUND: The evidence that the variants GCK rs1799884, GCKR rs780094, MTNR1B rs10830963 and G6PC2 rs560887, which are related to fasting plasma glucose levels, increase the risk of type 2 diabetes mellitus (T2DM is contradictory. We therefore performed a meta-analysis to derive a more precise estimation of the association between these polymorphisms and T2DM. METHODS: All the publications examining the associations of these variants with risk of T2DM were retrieved from the MEDLINE and EMBASE databases. Using the data from the retrieved articles, we computed summary estimates of the associations of the four variants with T2DM risk. We also examined the studies for heterogeneity, as well as for bias of the publications. RESULTS: A total of 113,025 T2DM patients and 199,997 controls from 38 articles were included in the meta-analysis. Overall, the pooled results indicated that GCK (rs1799884, GCKR (rs780094 and MTNR1B (rs10830963 were significantly associated with T2DM susceptibility (OR, 1.04; 95%CI, 1.01-1.08; OR, 1.08; 95%CI, 1.05-1.12 and OR, 1.05; 95%CI, 1.02-1.08, respectively. After stratification by ethnicity, significant associations for the GCK, MTNR1B and G6PC2 variants were detected only in Caucasians (OR, 1.09; 95%CI, 1.02-1.16; OR, 1.10; 95%CI, 1.08-1.13 and OR, 0.97; 95%CI, 0.95-0.99, respectively, but not in Asians (OR, 1.02, 95% CI 0.98-1.05; OR, 1.01; 95%CI, 0.98-1.04 and OR, 1.12; 95%CI, 0.91-1.32, respectively. CONCLUSIONS: Our meta-analyses demonstrated that GCKR rs780094 variant confers high cross-ethnicity risk for the development of T2DM, while significant associations between GCK, MTNR1B and G6PC2 variants and T2DM risk are limited to Caucasians.

  19. The Treatment of Restless Legs Syndrome and Periodic Limb Movement Disorder in Adults—An Update for 2012: Practice Parameters with an Evidence-Based Systematic Review and Meta-Analyses

    Science.gov (United States)

    Aurora, R. Nisha; Kristo, David A.; Bista, Sabin R.; Rowley, James A.; Zak, Rochelle S.; Casey, Kenneth R.; Lamm, Carin I.; Tracy, Sharon L.; Rosenberg, Richard S.

    2012-01-01

    A systematic literature review and meta-analyses (where appropriate) were performed to update the previous AASM practice parameters on the treatments, both dopaminergic and other, of RLS and PLMD. A considerable amount of literature has been published since these previous reviews were performed, necessitating an update of the corresponding practice parameters. Therapies with a STANDARD level of recommendation include pramipexole and ropinirole. Therapies with a GUIDELINE level of recommendation include levodopa with dopa decarboxylase inhibitor, opioids, gabapentin enacarbil, and cabergoline (which has additional caveats for use). Therapies with an OPTION level of recommendation include carbamazepine, gabapentin, pregabalin, clonidine, and for patients with low ferritin levels, iron supplementation. The committee recommends a STANDARD AGAINST the use of pergolide because of the risks of heart valve damage. Therapies for RLS secondary to ESRD, neuropathy, and superficial venous insufficiency are discussed. Lastly, therapies for PLMD are reviewed. However, it should be mentioned that because PLMD therapy typically mimics RLS therapy, the primary focus of this review is therapy for idiopathic RLS. Citation: Aurora RN; Kristo DA; Bista SR; Rowley JA: Zak RS; Casey KR; Lamm CI; Tracy SL; Rosenberg RS. The treatment of restless legs syndrome and periodic limb movement disorder in adults—an update for 2012: practice parameters with an evidence-based systematic review and meta-analyses. SLEEP 2012;35(8):1039-1062. PMID:22851801

  20. The PRISMA extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions:checklist and explanations%系统综述与网状Meta分析的PRISMA扩展声明

    Institute of Scientific and Technical Information of China (English)

    李志霞; 杨俊; 叶欣; 周凌波; 杨智荣; 孙凤; 詹思延(审校)

    2016-01-01

    The PRISMA statement is a reporting guideline designed to improve the completeness of reporting of systematic reviews and meta-analyses. Authors have used this guideline worldwide to prepare their reviews for publication. In the past, these reports typically compared 2 treatment alternatives. With the evolution of systematic reviews that compare multiple treatments, some of them only indirectly, authors face novel challenges for conducting and reporting their reviews. This extension of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) statement was developed specifically to improve the reporting of systematic reviews incorporating network meta-analyses. A group of experts participated in a systematic review, Delphi survey, and face-to-face discussion and consensus meeting to establish new checklist items for this extension statement. Current PRISMA items were also clarified. A modified, 32-item PRISMA extension checklist was developed to address what the group considered to be immediately relevant to the reporting of network meta-analyses. This document presents the extension and provides examples of good reporting, as well as elaborations regarding the rationale for new checklist items and the modification of previously existing items from the PRISMA statement. It also highlights educational information related to key considerations in the practice of network meta-analysis. The target audience includes authors and readers of network meta-analyses, as well as journal editors and peer reviewers.%PRISMA声明旨在提高系统综述和META分析报告的完整性,该声明已经广泛用于指导系统综述和META分析的报告和发表。原始的PRISMA声明是针对两种干预措施比较的传统的系统综述与META分析而制定的,然而,随着多种干预措施比较的系统综述的发展,实施和报告这一类系统综述面临较大挑战。此时,针对网状META分析的PRISMA扩展声明应运而生,旨

  1. Copy number variation in glutathione S-transferases M1 and T1 and ischemic vascular disease: four studies and meta-analyses

    DEFF Research Database (Denmark)

    Nørskov, Marianne S; Frikke-Schmidt, Ruth; Loft, Steffen

    2011-01-01

    Glutathione S-transferases (GSTs) M1 and T1 detoxify products of oxidative stress and may protect against atherosclerosis and ischemic vascular disease (IVD). We tested the hypothesis that copy number variation (CNV) in GSTM1 and GSTT1 genes, known to be associated with stepwise decreases in cata...

  2. Identification of a novel FGFRL1 MicroRNA target site polymorphism for bone mineral density in meta-analyses of genome-wide association studies

    NARCIS (Netherlands)

    T. Niu (Tianhua); N. Liu (Ning); M. Zhao (Ming); G. Xie (Guie); L. Zhang (Lei); J. Li (Jian); Y.-F. Pei (Yu-Fang); H. Shen (Hui); X. Fu (Xiaoying); H. He (Hao); S. Lu (Shan); X. Chen (Xiangding); L. Tan (Lijun); T.-L. Yang (Tie-Lin); Y. Guo (Yan); P.J. Leo (Paul); E.L. Duncan (Emma); J. Shen (Jie); Y.-F. Guo (Yan-fang); G.C. Nicholson (Geoffrey); R.L. Prince (Richard L.); J.A. Eisman (John); G. Jones (Graeme); P.N. Sambrook (Philip); X. Hu (Xiang); P.M. Das (Partha M.); Q. Tian (Qing); X.-Z. Zhu (Xue-Zhen); C.J. Papasian (Christopher J.); M.A. Brown (Matthew); A.G. Uitterlinden (André G.); Y.-P. Wang (Yu-Ping); S. Xiang (Shuanglin); H.-W. Deng

    2015-01-01

    textabstractMicroRNAs (miRNAs) are critical post-transcriptional regulators. Based on a previous genome-wide association (GWA) scan, we conducted a polymorphism in microRNAs' Target Sites (poly-miRTS)-centric multistage meta-analysis for lumbar spine (LS)-, total hip (HIP)-, and femoral neck (FN)-bo

  3. Does low-energy sweetener consumption affect energy intake and body weight? A systematic review, including meta-analyses, of the evidence from human and animal studies

    NARCIS (Netherlands)

    Rogers, P.J.; Hogenkamp, P.S.; Graaf, de Kees; Higgs, S.; Lluch, A.; Ness, A.R.; Penfold, C.; Perry, R.; Putz, P.; Yeomans, M.R.; Mela, D.J.

    2016-01-01

    By reducing energy density, low-energy sweeteners (LES) might be expected to reduce energy intake (EI) and body weight (BW). To assess the totality of the evidence testing the null hypothesis that LES exposure (versus sugars or unsweetened alternatives) has no effect on EI or BW, we conducted a s

  4. Gr/gr deletions on Y-chromosome correlate with male infertility: an original study, meta-analyses, and trial sequential analyses.

    Science.gov (United States)

    Bansal, Sandeep Kumar; Jaiswal, Deepika; Gupta, Nishi; Singh, Kiran; Dada, Rima; Sankhwar, Satya Narayan; Gupta, Gopal; Rajender, Singh

    2016-02-15

    We analyzed the AZFc region of the Y-chromosome for complete (b2/b4) and distinct partial deletions (gr/gr, b1/b3, b2/b3) in 822 infertile and 225 proven fertile men. We observed complete AZFc deletions in 0.97% and partial deletions in 6.20% of the cases. Among partial deletions, the frequency of gr/gr deletions was the highest (5.84%). The comparison of partial deletion data between cases and controls suggested a significant association of the gr/gr deletions with infertility (P = 0.0004); however, the other partial deletions did not correlate with infertility. In cohort analysis, men with gr/gr deletions had a relatively poor sperm count (54.20 ± 57.45 million/ml) in comparison to those without deletions (72.49 ± 60.06), though the difference was not statistically significant (p = 0.071). Meta-analysis also suggested that gr/gr deletions are significantly associated with male infertility risk (OR = 1.821, 95% CI = 1.39-2.37, p = 0.000). We also performed trial sequential analyses that strengthened the evidence for an overall significant association of gr/gr deletions with the risk of male infertility. Another meta-analysis suggested a significant association of the gr/gr deletions with low sperm count. In conclusion, the gr/gr deletions show a strong correlation with male infertility risk and low sperm count, particularly in the Caucasian populations.

  5. Does low-energy sweetener consumption affect energy intake and body weight? A systematic review, including meta-analyses, of the evidence from human and animal studies

    NARCIS (Netherlands)

    Rogers, P.J.; Hogenkamp, P.S.; Graaf, de Kees; Higgs, S.; Lluch, A.; Ness, A.R.; Penfold, C.; Perry, R.; Putz, P.; Yeomans, M.R.; Mela, D.J.

    2016-01-01

    By reducing energy density, low-energy sweeteners (LES) might be expected to reduce energy intake (EI) and body weight (BW). To assess the totality of the evidence testing the null hypothesis that LES exposure (versus sugars or unsweetened alternatives) has no effect on EI or BW, we conducted a

  6. Genome-Wide Meta-Analyses of Breast, Ovarian, and Prostate Cancer Association Studies Identify Multiple New Susceptibility Loci Shared by at Least Two Cancer Types

    DEFF Research Database (Denmark)

    Kar, Siddhartha P; Beesley, Jonathan; Amin Al Olama, Ali

    2016-01-01

    ,349 cases and 116,421 controls of European ancestry, all together and in pairs, identified at P risk loci......: We demonstrate that combining large-scale GWA meta-analysis findings across cancer types can identify completely new risk loci common to breast, ovarian, and prostate cancers. We show that the identification of such cross-cancer risk loci has the potential to shed new light on the shared biology...... (rs200182588/9q31/SMC2; rs8037137/15q26/RCCD1), and two breast and prostate cancer risk loci (rs5013329/1p34/NSUN4; rs9375701/6q23/L3MBTL3). Index variants in five additional regions previously associated with only one cancer also showed clear association with a second cancer type. Cell...

  7. Evaluation of the endorsement of the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement on the quality of published systematic review and meta-analyses.

    Science.gov (United States)

    Panic, Nikola; Leoncini, Emanuele; de Belvis, Giulio; Ricciardi, Walter; Boccia, Stefania

    2013-01-01

    PRISMA statement was published in 2009 in order to set standards in the reporting of systematic reviews and meta-analyses. Our aim was to evaluate the impact of PRISMA endorsement on the quality of reporting and methodological quality of systematic reviews and meta-analyses, published in journals in the field of gastroenterology and hepatology (GH). Quality of reporting and methodological quality were evaluated by assessing the adherence of papers to PRISMA checklist and AMSTAR quality scale. After identifying the GH journals which endorsed PRISMA in instructions for authors (IA), we appraised: 15 papers published in 2012 explicitly mentioning PRISMA in the full text (Group A); 15 papers from the same journals published in 2012 not explicitly mentioning PRISMA in the full text (Group B); 30 papers published the year preceding PRISMA endorsement from the same journals as above (Group C); 30 papers published in 2012 on the 10 highest impact factor journals in GH which not endorsed PRISMA (Group D). PRISMA statement was referred in the IA in 9 out of 70 GH journals (12.9%). We found significant increase in overall adherence to PRISMA checklist (Group A, 90.1%; Group C, 83.1%; p = 0.003) and compliance to AMSTAR scale (Group A, 85.0%; Group C, 74.6%; p = 0.002), following the PRISMA endorsement from the nine GH journals. Explicit referencing of PRISMA in manuscript was not associated with increase in quality of reporting and methodological quality (Group A vs. B, p = 0.651, p = 0.900, respectively). Adherence to PRISMA checklist, and the compliance with AMSTAR were significantly higher in journals endorsing PRISMA compared to those not (Groups A+B vs. D; p = 0.003 and p = 0.016, respectively). The endorsement of PRISMA resulted in increase of both quality of reporting and methodological quality. It is advised that an increasing number of medical journals include PRISMA in the instructions for authors.

  8. Prevention and Treatment of Complications after Impacted Tooth Extraction: An Overview of Systematic Reviews and Meta-Analyses%阻生牙拔除术后并发症防治的系统评价/Meta分析的汇总评价

    Institute of Scientific and Technical Information of China (English)

    菅玥; 王竹; 白晨潞; 程珍; 徐海丽; 古丽萍; 曾宪涛

    2013-01-01

    Objective To evaluate the relevant systematic reviews/meta-analyses that focused on the prevention and treatment of complications after impacted tooth extraction.Methods The systematic reviews/meta-analyses on the prevention and treatment of complications after impacted tooth extraction were searched in PubMed,The Cochrane Library,CBM,CNKI and WanFang Data from inception to September 30th,2012,and a total of 15 professional journals and the references of included studies were also retrieved manually.Two reviewers screened the literature according to the inclusion criteria and extracted the data.Then the AMSTAR was used to evaluate the quality of the included studies,and the GRADE system was used to evaluate the quality of evidence.Results A total of twelve relevant systematic reviews/ meta-analyses were included,of which five focused on the prevention and treatment of dry socket,six on the prevention of swelling,seven on the prevention and treatment of pain,six on the prevention of limitation of mouth opening,two on the prevention of infection,three on the prevention of bleeding,and one on the treatment of nerve damage after tooth extraction.Based on AMSTAR,seven studies were minor limitations and five studies were moderate limitations.Based on GRADE system,two was high quality of evidence,twelve were moderate,nine were low,and seven were very low.Conclusion Currently,the systematic reviews/meta-analyses on the prevention and treatment of complications after impacted tooth extraction can provide some references for clinical practice,which should be combined with the real condition by clinical doctors when making an evidence-based decision.However,it also suggests performing more high quality and large sample studies to prove this conclusion.%目的 对防治阻生牙拔除术后并发症的系统评价/Meta分析进行汇总评价.方法 计算机检索PubMed、The Cochrane Library、CBM、CNKI和WanFang Data,收集防治阻生牙拔除术后并发症的所有系

  9. Folic acid alone or multivitamin containing folic acid intake during pregnancy and the risk of gestational hypertension and preeclampsia through meta-analyses

    OpenAIRE

    Shim, Sang-Min; Yun, Yeo-Ul; Kim, Yun Sook

    2016-01-01

    Objective The objective of this study was to assess the effect of folic acid and multivitamin use during pregnancy on the risk of developing of hypertensive disorder of pregnancy. Methods Two reviewers independently determined all prospective cohort study, retrospective cohort study, large population based cohort study, retrospective secondary analysis, and double blinded, placebo-controlled, randomized clinical trial published using PubMed Medline database, KERIS (Korea Education and Researc...

  10. Abdominal Obesity and Lung Cancer Risk: Systematic Review and Meta-Analysis of Prospective Studies

    OpenAIRE

    Khemayanto Hidayat; Xuan Du; Guochong Chen; Minhua Shi; Bimin Shi

    2016-01-01

    Several meta-analyses of observational studies have been performed to examine the association between general obesity, as measured by body mass index (BMI), and lung cancer. These meta-analyses suggest an inverse relation between high BMI and this cancer. In contrast to general obesity, abdominal obesity appears to play a role in the development of lung cancer. However, the association between abdominal obesity (as measured by waist circumference (WC) (BMI adjusted) and waist to hip ratio (WH...

  11. Systematic review using meta-analyses to estimate dose-response relationships between iodine intake and biomarkers of iodine status in different population groups.

    Science.gov (United States)

    Ristić-Medić, Danijela; Dullemeijer, Carla; Tepsić, Jasna; Petrović-Oggiano, Gordana; Popović, Tamara; Arsić, Aleksandra; Glibetić, Marija; Souverein, Olga W; Collings, Rachel; Cavelaars, Adriënne; de Groot, Lisette; van't Veer, Pieter; Gurinović, Mirjana

    2014-03-01

    The objective of this systematic review was to identify studies investigating iodine intake and biomarkers of iodine status, to assess the data of the selected studies, and to estimate dose-response relationships using meta-analysis. All randomized controlled trials, prospective cohort studies, nested case-control studies, and cross-sectional studies that supplied or measured dietary iodine and measured iodine biomarkers were included. The overall pooled regression coefficient (β) and the standard error of β were calculated by random-effects meta-analysis on a double-log scale, using the calculated intake-status regression coefficient (β) for each individual study. The results of pooled randomized controlled trials indicated that the doubling of dietary iodine intake increased urinary iodine concentrations by 14% in children and adolescents, by 57% in adults and the elderly, and by 81% in pregnant women. The dose-response relationship between iodine intake and biomarkers of iodine status indicated a 12% decrease in thyroid-stimulating hormone and a 31% decrease in thyroglobulin in pregnant women. The model of dose-response quantification used to describe the relationship between iodine intake and biomarkers of iodine status may be useful for providing complementary evidence to support recommendations for iodine intake in different population groups.

  12. The relationship between zinc intake and serum/plasma zinc concentration in pregnant and lactating women: A systematic review with dose-response meta-analyses

    NARCIS (Netherlands)

    Hall Moran, V.; Skinner, A.L.; Warthon Medina, M.; Patel, S.; Dykes, F.; Souverein, O.W.; Dullemeijer, C.; Lowe, N.M.M.

    2012-01-01

    Recommendations for zinc intake during pregnancy and lactation vary widely across Europe. Using data on zinc intake and biomarkers of zinc status reported in randomized controlled trials (RCTs) and observational studies can provide estimates of dose–response relationships that may be used for underp

  13. No evidence for genome-wide interactions on plasma fibrinogen by smoking, alcohol consumption and body mass index : Results from meta-analyses of 80,607 subjects

    NARCIS (Netherlands)

    J. Baumert (Jens); J. Huang (Jian); B. McKnight (Barbara); M. Sabater-Lleal (Maria); M. Steri (Maristella); A.Y. Chu (Audrey); S. Trompet (Stella); Lopez, L.M. (Lorna M.); Fornage, M. (Myriam); A. Teumer (Alexander); W. Tang (Weihong); A.R. Rudnicka (Alicja); A. Mälarstig (Anders); J.J. Hottenga (Jouke Jan); M. Kavousi (Maryam); J. Lahti (Jari); T. Tanaka (Toshiko); C. Hayward (Caroline); J.E. Huffman (Jennifer); P.-E. Morange (P.); L.M. Rose (Lynda); S. Basu (Saonli); A. Rumley (Ann); D.J. Stott (David. J.); B.M. Buckley (Brendan M.); A.J. de Craen (Anton); S. Sanna (Serena); G. Masala (Giovanna); R. Biffar (Reiner); G. Homuth (Georg); A. Silveira (Angela); B. Sennblad (Bengt); A. Goel (Anuj); H. Watkins (Hugh); M. Müller-Nurasyid (Martina); Rückerl, R. (Regina); K.D. Taylor (Kent); Chen, M.-H. (Ming-Huei); E.J.C. de Geus (Eco); A. Hofman (Albert); J.C.M. Witteman (Jacqueline); M.P.M. de Maat (Moniek); A. Palotie (Aarno); G. Davies (Gail); D.S. Siscovick (David); I. Kolcic (Ivana); S.H. Wild (Sarah); Song, J. (Jaejoon); W.L. McArdle (Wendy); I. Ford (Ian); N. Sattar (Naveed); D. Schlessinger (David); A. Grotevendt (Anne); M. Franzosi; Illig, T. (Thomas); M. Waldenberger (Melanie); T. Lumley (Thomas); G.H. Tofler (Geoffrey); G.A.H.M. Willemsen (Gonneke); A.G. Uitterlinden (André); F. Rivadeneira Ramirez (Fernando); K. Räikkönen (Katri); D.I. Chasman (Daniel); A.R. Folsom (Aaron); G.D.O. Lowe (Gordon); R.G.J. Westendorp (Rudi); P.E. Slagboom (Eline); F. Cucca (Francesco); H. Wallaschofski (Henri); R.J. Strawbridge (Rona); U. Seedorf (Udo); W. Koenig (Wolfgang); J.C. Bis (Joshua); K. Mukamal (Kenneth); Van Dongen, J. (Jenny); E. Widen (Elisabeth); O.H. Franco (Oscar); J.M. Starr (John); K.Y. Liu; L. Ferrucci (Luigi); O. Polasek (Ozren); J.F. Wilson (James F); T. Oudot-Mellakh (Tiphaine); H. Campbell (Harry); P. Navarro (Pau); S. Bandinelli (Stefania); Eriksson, J. (Johan); D.I. Boomsma (Dorret); A. Dehghan (Abbas); R. Clarke (Robert); A. Hamsten (Anders); Boerwinkle, E. (Eric); J.W. Jukema (Jan Wouter); S. Naitza (Silvia); P.M. Ridker (Paul); H. Völzke (Henry); Deary, I.J. (Ian J.); A. Reiner (Alexander); D.-A. Tregouet (David-Alexandre); C.J. O'Donnell (Christopher); D.P. Strachan (David); A. Peters (Annette); Smith, N.L. (Nicholas L.)

    2014-01-01

    textabstractPlasma fibrinogen is an acute phase protein playing an important role in the blood coagulation cascade having strong associations with smoking, alcohol consumption and body mass index (BMI). Genome-wide association studies (GWAS) have identified a variety of gene regions associated with

  14. Prevalence of Cannabis Lifetime Use in Iranian High School and College Students: A Systematic Review, Meta-Analyses, and Meta-Regression.

    Science.gov (United States)

    Nazarzadeh, Milad; Bidel, Zeinab; Mosavi Jarahi, Alireza; Esmaeelpour, Keihan; Menati, Walieh; Shakeri, Ali Asghar; Menati, Rostam; Kikhavani, Sattar; Saki, Kourosh

    2015-09-01

    Cannabis is the most widely used substance in the world. This study aimed to estimate the prevalence of cannabis lifetime use (CLU) in high school and college students of Iran and also to determine factors related to changes in prevalence. A systematic review of literature on cannabis use in Iran was conducted according to MOOSE guideline. Domestic scientific databases, PubMed/Medline, ISI Web of Knowledge, and Google Scholar, relevant reference lists, and relevant journals were searched up to April, 2014. Prevalences were calculated using the variance stabilizing double arcsine transformation and confidence intervals (CIs) estimated using the Wilson method. Heterogeneity was assessed by Cochran's Q statistic and I(2) index and causes of heterogeneity were evaluated using meta-regression model. In electronic database search, 4,000 citations were retrieved, producing a total of 33 studies. CLU was reported with a random effects pooled prevalence of 4.0% (95% CI = 3.0% to 5.0%). In subgroups of high school and college students, prevalences were 5.0% (95% CI = 3.0% to -7.0%) and 2.0% (95% CI = 2.0% to -3.0%), respectively. Meta-regression model indicated that prevalence is higher in college students (β = 0.089, p < .001), male gender (β = 0.017, p < .001), and is lower in studies with sampling versus census studies (β = -0.096, p < .001). This study reported that prevalence of CLU in Iranian students are lower than industrialized countries. In addition, gender, level of education, and methods of sampling are highly associated with changes in the prevalence of CLU across provinces.

  15. The Efficacy of Psychological Therapies in Reducing Weight and Binge Eating in People with Bulimia Nervosa and Binge Eating Disorder Who Are Overweight or Obese—A Critical Synthesis and Meta-Analyses

    Directory of Open Access Journals (Sweden)

    Marly Amorim Palavras

    2017-03-01

    Full Text Available Recurrent binge eating episodes, the core feature of Bulimia Nervosa (BN and Binge Eating Disorder (BED, are frequently comorbid with obesity. Psychological interventions, notably Cognitive Behavioural Therapy (CBT, are effective for binge eating reduction in BED or BN but less so for weight loss. Behavioural Weight Loss Therapy (BWLT shows effectiveness for binge eating reduction and weight loss but the latter appears poorly sustained over time. Our aim was to review evidence for efficacy of psychological therapies for BN/BED associated with overweight or obesity in reducing binge frequency and weight. A systematic search for randomized controlled trials with adult samples who had BN or BED was conducted considering articles in English, French, Spanish and Portuguese with no restrictions for the timeline publication ending in March 2016. A quality appraisal of the trials and meta-analyses comparing BWLT to CBT were done. This review identified 2248 articles for screening and 19 published articles were selected. No trials of BN were identified. This review found CBT was favoured compared to BWLT with regard to short-term binge eating reduction. However, insufficient evidence was found for superiority for BWLT efficacy compared to CBT considering binge eating remission, reduction of binge eating frequency and weight loss. More research is needed to test the efficacy of psychological treatments for BED or BN with co-morbid overweight or obesity, including trials evaluating binge eating remission and weight loss in the long-term.

  16. The treatment of restless legs syndrome and periodic limb movement disorder in adults--an update for 2012: practice parameters with an evidence-based systematic review and meta-analyses: an American Academy of Sleep Medicine Clinical Practice Guideline.

    Science.gov (United States)

    Aurora, R Nisha; Kristo, David A; Bista, Sabin R; Rowley, James A; Zak, Rochelle S; Casey, Kenneth R; Lamm, Carin I; Tracy, Sharon L; Rosenberg, Richard S

    2012-08-01

    A systematic literature review and meta-analyses (where appropriate) were performed to update the previous AASM practice parameters on the treatments, both dopaminergic and other, of RLS and PLMD. A considerable amount of literature has been published since these previous reviews were performed, necessitating an update of the corresponding practice parameters. Therapies with a STANDARD level of recommendation include pramipexole and ropinirole. Therapies with a GUIDELINE level of recommendation include levodopa with dopa decarboxylase inhibitor, opioids, gabapentin enacarbil, and cabergoline (which has additional caveats for use). Therapies with an OPTION level of recommendation include carbamazepine, gabapentin, pregabalin, clonidine, and for patients with low ferritin levels, iron supplementation. The committee recommends a STANDARD AGAINST the use of pergolide because of the risks of heart valve damage. Therapies for RLS secondary to ESRD, neuropathy, and superficial venous insufficiency are discussed. Lastly, therapies for PLMD are reviewed. However, it should be mentioned that because PLMD therapy typically mimics RLS therapy, the primary focus of this review is therapy for idiopathic RLS.

  17. The Efficacy of Psychological Therapies in Reducing Weight and Binge Eating in People with Bulimia Nervosa and Binge Eating Disorder Who Are Overweight or Obese—A Critical Synthesis and Meta-Analyses

    Science.gov (United States)

    Palavras, Marly Amorim; Hay, Phillipa; dos Santos Filho, Celso Alves; Claudino, Angélica

    2017-01-01

    Recurrent binge eating episodes, the core feature of Bulimia Nervosa (BN) and Binge Eating Disorder (BED), are frequently comorbid with obesity. Psychological interventions, notably Cognitive Behavioural Therapy (CBT), are effective for binge eating reduction in BED or BN but less so for weight loss. Behavioural Weight Loss Therapy (BWLT) shows effectiveness for binge eating reduction and weight loss but the latter appears poorly sustained over time. Our aim was to review evidence for efficacy of psychological therapies for BN/BED associated with overweight or obesity in reducing binge frequency and weight. A systematic search for randomized controlled trials with adult samples who had BN or BED was conducted considering articles in English, French, Spanish and Portuguese with no restrictions for the timeline publication ending in March 2016. A quality appraisal of the trials and meta-analyses comparing BWLT to CBT were done. This review identified 2248 articles for screening and 19 published articles were selected. No trials of BN were identified. This review found CBT was favoured compared to BWLT with regard to short-term binge eating reduction. However, insufficient evidence was found for superiority for BWLT efficacy compared to CBT considering binge eating remission, reduction of binge eating frequency and weight loss. More research is needed to test the efficacy of psychological treatments for BED or BN with co-morbid overweight or obesity, including trials evaluating binge eating remission and weight loss in the long-term. PMID:28304341

  18. The Efficacy of Psychological Therapies in Reducing Weight and Binge Eating in People with Bulimia Nervosa and Binge Eating Disorder Who Are Overweight or Obese-A Critical Synthesis and Meta-Analyses.

    Science.gov (United States)

    Palavras, Marly Amorim; Hay, Phillipa; Filho, Celso Alves Dos Santos; Claudino, Angélica

    2017-03-17

    Recurrent binge eating episodes, the core feature of Bulimia Nervosa (BN) and Binge Eating Disorder (BED), are frequently comorbid with obesity. Psychological interventions, notably Cognitive Behavioural Therapy (CBT), are effective for binge eating reduction in BED or BN but less so for weight loss. Behavioural Weight Loss Therapy (BWLT) shows effectiveness for binge eating reduction and weight loss but the latter appears poorly sustained over time. Our aim was to review evidence for efficacy of psychological therapies for BN/BED associated with overweight or obesity in reducing binge frequency and weight. A systematic search for randomized controlled trials with adult samples who had BN or BED was conducted considering articles in English, French, Spanish and Portuguese with no restrictions for the timeline publication ending in March 2016. A quality appraisal of the trials and meta-analyses comparing BWLT to CBT were done. This review identified 2248 articles for screening and 19 published articles were selected. No trials of BN were identified. This review found CBT was favoured compared to BWLT with regard to short-term binge eating reduction. However, insufficient evidence was found for superiority for BWLT efficacy compared to CBT considering binge eating remission, reduction of binge eating frequency and weight loss. More research is needed to test the efficacy of psychological treatments for BED or BN with co-morbid overweight or obesity, including trials evaluating binge eating remission and weight loss in the long-term.

  19. Evaluation of the Expanded Disability Status Scale and the Multiple Sclerosis Functional Composite as clinical endpoints in multiple sclerosis clinical trials: quantitative meta-analyses.

    Science.gov (United States)

    Bin Sawad, Aseel; Seoane-Vazquez, Enrique; Rodriguez-Monguio, Rosa; Turkistani, Fatema

    2016-12-01

    This study compared the sensitivity of the Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Functional Composite (MSFC) as clinical endpoints in multiple sclerosis (MS) clinical trials. Medline (1946 through 12 September 2014) and Embase (1974 through 12 September 2014) databases searches were conducted using keywords and Medical Subject Heading (MeSH) terms related to MS, EDSS, and MSFC. Only studies that used the EDSS and MSFC as endpoints were assessed. All statistical analyses were conducted using comprehensive meta-analysis (CMA). The percentages of the overall changes in EDSS and MSFC were compared. The relative risks were calculated in randomized clinical trials (RCTs). A total of 123 studies were identified. There were nine studies (6 case series and 3 RCTs) included in the analysis. In the case series, the EDSS change rate in MS patients was 33.5% (95% CI: 12.9-63.2%) and the MSFC change rate was 30.3% (95% CI: 9.2-65.2%). In RCTs, patients who take the drug would be 22.9 times as likely as patients who did not take the drug to experience a change in the EDSS scale (RR = 22.9, 95% CI = 0.996-1.517, p = 0.055). Patients who take the drug would be 48.9 times as likely as patients who did not take the drug to experience a change in the MSFC scale (RR = 48.9, 95% CI = CI = 0.916-2.419, p = 0.108). This study focused only on MS patient improvement (positive changes) on the EDSS and MSFC. More studies are needed to include patient deterioration (negative changes) on EDSS and MSFC. There is controversy about the sensitivity of the EDSS and MSFC in detecting the progression of MS disease. The EDSS and MSFC are effective tools to assess the clinical severity and progression of MS disease. MSFC is more sensitive than EDSS in detecting the progression of MS disease.

  20. Weight Loss Instead of Weight Gain within the Guidelines in Obese Women during Pregnancy: A Systematic Review and Meta-Analyses of Maternal and Infant Outcomes.

    Directory of Open Access Journals (Sweden)

    Mufiza Zia Kapadia

    Full Text Available Controversy exists about how much, if any, weight obese pregnant women should gain. While the revised Institute of Medicine guidelines on gestational weight gain (GWG in 2009 recommended a weight gain of 5-9 kg for obese pregnant women, many studies suggested even gestational weight loss (GWL for obese women.A systematic review was conducted to summarize pregnancy outcomes in obese women with GWL compared to GWG within the 2009 Institute of Medicine guidelines (5-9 kg.Five databases were searched from 1 January 2009 to 31 July 2014. The Cochrane Handbook for Systematic Reviews of Interventions and the PRISMA Statement were followed. A modified version of the Newcastle-Ottawa scale was used to assess individual study quality. Small for gestational age (SGA, large for gestational age (LGA and preterm birth were our primary outcomes.Six cohort studies were included, none of which assessed preterm birth. Compared to GWG within the guidelines, women with GWL had higher odds of SGA 90th percentile (AOR 0.57; 95% CI 0.52-0.62. There was a trend towards a graded relationship between SGA <10th percentile and each of three obesity classes (I: AOR 1.73; 95% CI 1.53-1.97; II: AOR 1.63; 95% CI 1.44-1.85 and III: AOR 1.39; 95% CI 1.17-1.66, respectively.Despite decreased odds of LGA, increased odds of SGA and a lack of information on preterm birth indicate that GWL should not be advocated in general for obese women.

  1. Interventions to improve the rate or timing of initiation of antiretroviral therapy for HIV in sub-Saharan Africa: meta-analyses of effectiveness

    Directory of Open Access Journals (Sweden)

    Matthew P Fox

    2016-08-01

    Full Text Available Introduction: As global policy evolves toward initiating lifelong antiretroviral therapy (ART regardless of CD4 count, initiating individuals newly diagnosed with HIV on ART as efficiently as possible will become increasingly important. To inform progress, we conducted a systematic review of pre-ART interventions aiming to increase ART initiation in sub-Saharan Africa. Methods: We searched PubMed, Embase and the ISI Web of Knowledge from 1 January 2008 to 1 March 2015, extended in PubMed to 25 May 2016, for English language publications pertaining to any country in sub-Saharan Africa and reporting on general adult populations. We included studies describing interventions aimed at increasing linkage to HIV care, retention in pre-ART or uptake of ART, which reported ART initiation as an outcome. We synthesized the evidence on causal intervention effects in meta-analysis of studies belonging to distinct intervention categories. Results and discussion: We identified 22 studies, which evaluated 25 interventions and included data on 45,393 individual patients. Twelve of twenty-two studies were observational. Rapid/point-of-care (POC CD4 count technology (seven interventions (relative risk, RR: 1.26; 95% confidence interval, CI: 1.02–1.55, interventions within home-based testing (two interventions (RR: 2.00; 95% CI: 1.36–2.92, improved clinic operations (three interventions (RR: 1.36; 95% CI: 1.25–1.48 and a package of patient-directed services (three interventions (RR: 1.54; 95% CI: 1.20–1.97 were all associated with increased ART initiation as was HIV/TB service integration (three interventions (RR: 2.05; 95% CI: 0.59–7.09 but with high imprecision. Provider-initiated testing (three interventions was associated with reduced ART initiation (RR: 0.91; 95% CI: 0.86–0.97. Counselling and support interventions (two interventions (RR 1.08; 95% CI: 0.94–1.26 had no impact on ART initiation. Overall, the evidence was graded as low or moderate

  2. Is grey literature essential for a better control of publication bias in psychiatry? An example from three meta-analyses of schizophrenia.

    Science.gov (United States)

    Martin, José Luis R; Pérez, Víctor; Sacristán, Montse; Alvarez, Enric

    2005-12-01

    Systematic reviews in mental health have become useful tools for health professionals in view of the massive amount and heterogeneous nature of biomedical information available today. In order to determine the risk of bias in the studies evaluated and to avoid bias in generalizing conclusions from the reviews it is therefore important to use a very strict methodology in systematic reviews. One bias which may affect the generalization of results is publication bias, which is determined by the nature and direction of the study results. To control or minimize this type of bias, the authors of systematic reviews undertake comprehensive searches of medical databases and expand on the findings, often undertaking searches of grey literature (material which is not formally published). This paper attempts to show the consequences (and risk) of generalizing the implications of grey literature in the control of publication bias, as was proposed in a recent systematic work. By repeating the analyses for the same outcome from three different systematic reviews that included both published and grey literature our results showed that confusion between grey literature and publication bias may affect the results of a concrete meta-analysis.

  3. The identification and treatment of women with hyperglycaemia in pregnancy: an analysis of individual participant data, systematic reviews, meta-analyses and an economic evaluation.

    Science.gov (United States)

    Farrar, Diane; Simmonds, Mark; Griffin, Susan; Duarte, Ana; Lawlor, Debbie A; Sculpher, Mark; Fairley, Lesley; Golder, Su; Tuffnell, Derek; Bland, Martin; Dunne, Fidelma; Whitelaw, Donald; Wright, John; Sheldon, Trevor A

    2016-01-01

    BACKGROUND Gestational diabetes mellitus (GDM) is associated with a higher risk of important adverse outcomes. Practice varies and the best strategy for identifying and treating GDM is unclear. AIM To estimate the clinical effectiveness and cost-effectiveness of strategies for identifying and treating women with GDM. METHODS We analysed individual participant data (IPD) from birth cohorts and conducted systematic reviews to estimate the association of maternal glucose levels with adverse perinatal outcomes; GDM prevalence; maternal characteristics/risk factors for GDM; and the effectiveness and costs of treatments. The cost-effectiveness of various strategies was estimated using a decision tree model, along with a value of information analysis to assess where future research might be worthwhile. Detailed systematic searches of MEDLINE(®) and MEDLINE In-Process & Other Non-Indexed Citations(®), EMBASE, Cumulative Index to Nursing and Allied Health Literature Plus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Health Technology Assessment database, NHS Economic Evaluation Database, Maternity and Infant Care database and the Cochrane Methodology Register were undertaken from inception up to October 2014. RESULTS We identified 58 studies examining maternal glucose levels and outcome associations. Analyses using IPD alone and the systematic review demonstrated continuous linear associations of fasting and post-load glucose levels with adverse perinatal outcomes, with no clear threshold below which there is no increased risk. Using IPD, we estimated glucose thresholds to identify infants at high risk of being born large for gestational age or with high adiposity; for South Asian (SA) women these thresholds were fasting and post-load glucose levels of 5.2 mmol/l and 7.2 mmol/l, respectively and for white British (WB) women they were 5.4 and 7.5 mmol/l, respectively. Prevalence

  4. Como avaliar criticamente revisões sistemáticas e metanálises? How to critically assess systematic reviews and meta-analyses?

    Directory of Open Access Journals (Sweden)

    Otávio Berwanger

    2007-12-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Revisões sistemáticas são ferramentas importantes no fornecimento de evidências para tomada de decisão na prática da Terapia Intensiva. O objetivo deste estudo foi descrever os elementos importantes na avaliação crítica das revisões sistemáticas existentes em Terapia Intensiva. CONTEÚDO: Na avaliação crítica da revisão sistemática, é necessário que o intensivista atente para a estruturação da questão a ser respondida, a estratégia de busca utilizada, os critérios de inclusão e a qualidade metodológica dos estudos incluídos, e como foram extraídos os dados levantados. Além disso, uma revisão sistemática relevante deve apresentar resultados consistentes (caso tenha sido realizada metanálise ou a causa de heterogeneidade deve ter sido explorada, e os resultados devem ser aplicáveis no paciente crítico. CONCLUSÕES: Para o correto emprego da evidência científica disponível, é necessário que o intensivista avalie criticamente a qualidade dos dados apresentados nas revisões sistemáticas, selecionando as informações relevantes para o manuseio do paciente crítico.BACKGROUND AND OBJECTIVES: Systematic reviews are important knowledge generating tools to help the decision making process in the Critical Care Unit. This narrative aims to describe the important elements used to critically appraise intensive care-related systematic reviews. CONTENTS: When critically assessing systematic reviews, one should pay particular attention to the importance and appropriateness of the research question, the search strategy, the inclusion criteria and methodological quality of the studies included, and the methods of data extraction. In addition, a relevant systematic review must have consistent data (in case of a meta-analysis or the cause of the heterogeneity must have been adequately explored, and results must be applicable in critical patients. CONCLUSIONS: To apply correctly the available

  5. Comparison of simple pooling and bivariate model used in meta-analyses of diagnos-tic test accuracy published in Chinese journals%简单合并模型与双变量模型在诊断试验Meta分析中的使用现状调查

    Institute of Scientific and Technical Information of China (English)

    黄元升; 杨智荣; 詹思延

    2015-01-01

    目的::调查2014年1月至11月国内期刊发表的诊断试验准确性( diagnostic test accuracy,DTA) Meta分析中简单合并模型与双变量模型的使用现状,分析两模型间结果的差异性,并探讨这种差异性与研究间异质性大小的关系。方法:对《中国生物医学文献数据库》2014年1月至11月收录的文献进行检索,纳入DTA Meta分析,描述模型使用的相关信息,提取四格表数据,使用简单合并模型和双变量模型进行重分析,用非参数检验比较模型结果间差值,定性探究灵敏度、特异度异质性大小与结果间差值的关系。结果:共纳入55篇文章,包括58个DTA Meta分析,其中25个Meta分析用于重分析。简单合并模型与双变量模型的使用比例分别为90.9%(50/55)、1.8%(1/55),使用其他合并模型或未合并灵敏度和特异度的文献比例为7.3%(4/55)。在50篇使用简单合并模型合并灵敏度和特异度的文章中,41篇(82.0%)存在误用Meta-disc软件的可能。两种模型所得灵敏度、特异度差值中位数均为0.011(P75%. Conclusion:Most DTA meta-analyses published in Chinese journals(January to November, 2014) combine the sensitivity and specificity by simple pooling. Meta-disc software can pool the sensitivity and specificity only through fixed-effect model, but a high proportion of authors think it can implement random-effect model. Simple pooling tends to underestimate the results compared with bivariate model. The greater the between-study variance is, the more likely the simple pooling has larger deviation. It is necessary to increase the knowledge level of statistical methods and software for meta-analyses of DTA data.

  6. How much of the data published in observational studies of the association between diet and prostate or bladder cancer is usable for meta-analysis?

    Science.gov (United States)

    Bekkering, Geertruida E; Harris, Ross J; Thomas, Steve; Mayer, Anne-Marie B; Beynon, Rebecca; Ness, Andrew R; Harbord, Roger M; Bain, Chris; Smith, George Davey; Sterne, Jonathan A C

    2008-05-01

    Epidemiologic investigations often report dose-response associations, which may be combined in meta-analyses. The authors examined how often the log odds, risk, or hazard ratio per unit increase in exposure, and its standard error, can be estimated from results reported from observational studies of diet and prostate or bladder cancer so that results are usable in meta-analyses estimating dose-response associations. Eight electronic databases were searched for studies reporting on the association of diet, nutrition, or physical activity with these cancers. A total of 767 papers reported 3,284 results; 1,999 (61%) results, reported in 545 (71%) papers, were usable in dose-response meta-analyses. The most important reason that results were not usable was the absence of sufficient information on exposure levels in the different groups. The proportion of results usable in "high-low" meta-analyses (comparisons of extreme categories) was similar (62%). Results that showed evidence of an association were more likely to be usable than results that found no such evidence. Insufficient detail in reporting of results of observational studies can lead to exclusion of these results from meta-analyses and is an important threat to the validity of systematic reviews of such research. Results providing evidence of associations may be overrepresented in meta-analyses of observational studies.

  7. Status Quo Analysis on TCM Systematic Reviews/Meta-Analyses Published in Chinese Journals%国内期刊发表的中医药系统评价/Meta分析的现状分析

    Institute of Scientific and Technical Information of China (English)

    陈敏; 何佳; 肖飏; 黄睿; 周智凤; 陈春雨; 王飞

    2012-01-01

    目的 了解目前中文期刊发表的中医药系统评价/Meta分析的现状.方法 计算机检索中国生物医学文献数据库(CBM,1978 ~ 2009.7.31),查找相关的中医药系统评价/Meta分析.对符合纳入标准的文献,根据研究目的提取相关信息,以发表年限、发表期刊、作者地区、作者数及发表篇数、病种和干预措施为分析指标,采用SPSS 15.0软件进行描述性分析.结果 共纳入245篇文献.其中中文238篇,英文7篇,分别发表于117种期刊,发表年限在1998 ~ 2008年,发文量呈加速增长趋势.该245篇文献的第一作者除1篇来自德国外,其余均来自国内24个省(自治区、直辖市);每篇文献作者数在1~11人不等;共有186人以第一作者身份发表过文章,发表篇数在1 ~ 29篇不等.文献涉及病种按国际疾病分类第十版(ICD-10)分类,共涉及16类.干预措施为药物者218篇(上市药物106篇,自拟方25篇,既涉及上市药又涉及自拟方70篇,未报告具体的干预措施17篇),占89%;非药物者27篇(针灸26篇,推拿1篇),占11%.药物干预中自拟方和上市药/自拟方绝大多数(95.8%)进行了不恰当的合并分析.结论 循证医学在国内中医领域的推广面已较广,中医药系统评价/Meta分析文献量呈加速增长的趋势,其涉及病种较好地覆盖了当前中医治疗的优势病种,但存在地区不平衡.今后药物干预的系统评价/Meta分析应更多针对中成药和单味药而非自拟方,并应更多关注优势病种和优势药物;非药物干预采用针灸时也要注意控制临床异质性.%Objective To learn the current situation of traditional Chinese medicine (TCM) systematic reviews/ meta-analyses published in Chinese journals. Methods All TCM systematic reviews/meta-analyses published from 1978 to July 31, 2009 were searched in the Chinese Biomedical Database (CBM). According to the inclusion and exclusion criteria, relevant information was extracted on the

  8. Publication and Quality of Systematic Reviews/Meta-Analyses Conducted by Hospital Pharmacists in China%国内医院药学人员系统评价/Meta分析文献发表与质量研究

    Institute of Scientific and Technical Information of China (English)

    闫盈盈; 易湛苗; 翟所迪

    2012-01-01

    Objective Through assessing the quality of systematic reviews/meta-analyses conducted by hospital pharmacists in China, to learn relevant situations and to promote the development and application of evidence-based pharmacy in hospital. Methods The following databases such as CBM, CNKI, Wanfang Database, VIP, CMCI, The Cochrane Library, Embase and PubMed were searched from the establishment date to April 15th, 2011, to collect all published systematic reviews/meta-analyses conducted by hospital pharmacists in China. Two reviewers independently extracted the published information according to the inclusive and exclusive criteria, and assessed the methodology and reporting quality of the included literatures with OQAQ and PRISMA. Disagreements were discussed or resolved by the third reviewer. Data analysis was conducted by using SPSS 17.0 software. Results Two hundred and sixteen Chinese literatures (including 40 on traditional Chinese medicine), and 15 English literatures were identified. The number of literatures has increased rapidly since 2008. Beijing and Sichuan were the top 2 districts in the number of literatures. All of the included literatures were published in 62 magazines sponsored by 87 hospitals, such as China Pharmacy, and Chinese Journey of Evidence-Based Medicine. The total downloads of Chinese literatures were 14346, and the total citations of all literatures were 154. The methodology and reporting quality of the randomized controlled trials (RCTs) involved in 220 systematic reviews/meta-analyses literatures were assessed, which showed the highest and lowest scores of methodological quality were 6 and 3, respectively, and the average score was 4.27±0.55. The highest and lowest scores of reporting quality were 22.5 and 9, respectively, and the average score was 16.49±2.98. Conclusion Although the evidence-based pharmacy in hospital begins late in China, it develops rapidly, and offers lots of evidence to policy decision, guidelines and rational drug

  9. Replication Validity of Initial Association Studies: A Comparison between Psychiatry, Neurology and Four Somatic Diseases

    Science.gov (United States)

    Dumas-Mallet, Estelle; Button, Katherine; Boraud, Thomas; Munafo, Marcus; Gonon, François

    2016-01-01

    Context There are growing concerns about effect size inflation and replication validity of association studies, but few observational investigations have explored the extent of these problems. Objective Using meta-analyses to measure the reliability of initial studies and explore whether this varies across biomedical domains and study types (cognitive/behavioral, brain imaging, genetic and “others”). Methods We analyzed 663 meta-analyses describing associations between markers or risk factors and 12 pathologies within three biomedical domains (psychiatry, neurology and four somatic diseases). We collected the effect size, sample size, publication year and Impact Factor of initial studies, largest studies (i.e., with the largest sample size) and the corresponding meta-analyses. Initial studies were considered as replicated if they were in nominal agreement with meta-analyses and if their effect size inflation was below 100%. Results Nominal agreement between initial studies and meta-analyses regarding the presence of a significant effect was not better than chance in psychiatry, whereas it was somewhat better in neurology and somatic diseases. Whereas effect sizes reported by largest studies and meta-analyses were similar, most of those reported by initial studies were inflated. Among the 256 initial studies reporting a significant effect (p<0.05) and paired with significant meta-analyses, 97 effect sizes were inflated by more than 100%. Nominal agreement and effect size inflation varied with the biomedical domain and study type. Indeed, the replication rate of initial studies reporting a significant effect ranged from 6.3% for genetic studies in psychiatry to 86.4% for cognitive/behavioral studies. Comparison between eight subgroups shows that replication rate decreases with sample size and “true” effect size. We observed no evidence of association between replication rate and publication year or Impact Factor. Conclusion The differences in reliability

  10. Meta-regression analyses, meta-analyses, and trial sequential analyses of the effects of supplementation with beta-carotene, vitamin A, and vitamin E singly or in different combinations on all-cause mortality: do we have evidence for lack of harm?

    Directory of Open Access Journals (Sweden)

    Goran Bjelakovic

    Full Text Available BACKGROUND AND AIMS: Evidence shows that antioxidant supplements may increase mortality. Our aims were to assess whether different doses of beta-carotene, vitamin A, and vitamin E affect mortality in primary and secondary prevention randomized clinical trials with low risk of bias. METHODS: The present study is based on our 2012 Cochrane systematic review analyzing beneficial and harmful effects of antioxidant supplements in adults. Using random-effects meta-analyses, meta-regression analyses, and trial sequential analyses, we examined the association between beta-carotene, vitamin A, and vitamin E, and mortality according to their daily doses and doses below and above the recommended daily allowances (RDA. RESULTS: We included 53 randomized trials with low risk of bias (241,883 participants, aged 18 to 103 years, 44.6% women assessing beta-carotene, vitamin A, and vitamin E. Meta-regression analysis showed that the dose of vitamin A was significantly positively associated with all-cause mortality. Beta-carotene in a dose above 9.6 mg significantly increased mortality (relative risk (RR 1.06, 95% confidence interval (CI 1.02 to 1.09, I(2 = 13%. Vitamin A in a dose above the RDA (> 800 µg did not significantly influence mortality (RR 1.08, 95% CI 0.98 to 1.19, I(2 = 53%. Vitamin E in a dose above the RDA (> 15 mg significantly increased mortality (RR 1.03, 95% CI 1.00 to 1.05, I(2 = 0%. Doses below the RDAs did not affect mortality, but data were sparse. CONCLUSIONS: Beta-carotene and vitamin E in doses higher than the RDA seem to significantly increase mortality, whereas we lack information on vitamin A. Dose of vitamin A was significantly associated with increased mortality in meta-regression. We lack information on doses below the RDA. BACKGROUND: All essential compounds to stay healthy cannot be synthesized in our body. Therefore, these compounds must be taken through our diet or obtained in other ways [1]. Oxidative stress has been

  11. Effects of blood-pressure-lowering treatment on outcome incidence in hypertension: 10 - Should blood pressure management differ in hypertensive patients with and without diabetes mellitus? Overview and meta-analyses of randomized trials.

    Science.gov (United States)

    Thomopoulos, Costas; Parati, Gianfranco; Zanchetti, Alberto

    2017-05-01

    Type 2 diabetes mellitus is associated with an increased risk of hypertension, and cardiovascular and renal disease, and it has been recommended that management of hypertension should be more aggressive in presence than in absence of diabetes mellitus, but the matter is controversial at present. Meta-analysing all available randomized controlled trials (RCTs) to compare the effects on cardiovascular and renal outcomes of blood pressure BP lowering to different systolic BP (SBP) and diastolic BP (DBP) levels or by different drug classes in patients with and without diabetes mellitus. The database consisted of 72 BP-lowering RCTs (260 210 patients) and 50 head-to-head drug comparison RCTs (247 006). Among these two sets, RCTs or RCT subgroups separately reporting data from patients with and without diabetes mellitus were identified, and stratified by in-treatment achieved SBP and DBP, by drug class compared with placebo, and drug class compared with all other classes. Risk ratios and 95% confidence intervals, and absolute risk reductions of six fatal and non-fatal cardiovascular outcomes, all-cause death, and end-stage renal disease (ESRD) were calculated (random-effects model) separately for diabetes mellitus and no diabetes mellitus, and compared by interaction analysis. We identified 41 RCTs providing data on 61 772 patients with diabetes mellitus and 40 RCTs providing data on 191 353 patients without diabetes mellitus. For achieved SBP at least 140 mmHg, relative and absolute reductions of most cardiovascular outcomes were significantly greater in diabetes mellitus than no diabetes mellitus, whereas for achieved SBP below 130 mmHg, the difference disappeared or reversed (greater outcome reduction in no diabetes mellitus). Significant ESRD reduction was found only in diabetes mellitus, but it was greatest when achieved SBP was at least 140 mmHg, and no further effect was found at SBP below 140 mmHg. All antihypertensive drug classes reduced

  12. The contribution of databases to the results of systematic reviews: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Lisa Hartling

    2016-09-01

    Full Text Available Abstract Background One of the best sources for high quality information about healthcare interventions is a systematic review. A well-conducted systematic review includes a comprehensive literature search. There is limited empiric evidence to guide the extent of searching, in particular the number of electronic databases that should be searched. We conducted a cross-sectional quantitative analysis to examine the potential impact of selective database searching on results of meta-analyses. Methods Our sample included systematic reviews (SRs with at least one meta-analysis from three Cochrane Review Groups: Acute Respiratory Infections (ARI, Infectious Diseases (ID, Developmental Psychosocial and Learning Problems (DPLP (n = 129. Outcomes included: 1 proportion of relevant studies indexed in each of 10 databases; and 2 changes in results and statistical significance of primary meta-analysis for studies identified in Medline only and in Medline plus each of the other databases. Results Due to variation across topics, we present results by group (ARI n = 57, ID n = 38, DPLP n = 34. For ARI, identification of relevant studies was highest for Medline (85 % and Embase (80 %. Restricting meta-analyses to trials that appeared in Medline + Embase yielded fewest changes in statistical significance: 53/55 meta-analyses showed no change. Point estimates changed in 12 cases; in 7 the change was less than 20 %. For ID, yield was highest for Medline (92 %, Embase (81 %, and BIOSIS (67 %. Restricting meta-analyses to trials that appeared in Medline + BIOSIS yielded fewest changes with 1 meta-analysis changing in statistical significance. Point estimates changed in 8 of 31 meta-analyses; change less than 20 % in all cases. For DPLP, identification of relevant studies was highest for Medline (75 % and Embase (62 %. Restricting meta-analyses to trials that appeared in Medline + PsycINFO resulted in only one change in

  13. Empirical evidence about inconsistency among studies in a pair-wise meta-analysis.

    Science.gov (United States)

    Rhodes, Kirsty M; Turner, Rebecca M; Higgins, Julian P T

    2016-12-01

    This paper investigates how inconsistency (as measured by the I(2) statistic) among studies in a meta-analysis may differ, according to the type of outcome data and effect measure. We used hierarchical models to analyse data from 3873 binary, 5132 continuous and 880 mixed outcome meta-analyses within the Cochrane Database of Systematic Reviews. Predictive distributions for inconsistency expected in future meta-analyses were obtained, which can inform priors for between-study variance. Inconsistency estimates were highest on average for binary outcome meta-analyses of risk differences and continuous outcome meta-analyses. For a planned binary outcome meta-analysis in a general research setting, the predictive distribution for inconsistency among log odds ratios had median 22% and 95% CI: 12% to 39%. For a continuous outcome meta-analysis, the predictive distribution for inconsistency among standardized mean differences had median 40% and 95% CI: 15% to 73%. Levels of inconsistency were similar for binary data measured by log odds ratios and log relative risks. Fitted distributions for inconsistency expected in continuous outcome meta-analyses using mean differences were almost identical to those using standardized mean differences. The empirical evidence on inconsistency gives guidance on which outcome measures are most likely to be consistent in particular circumstances and facilitates Bayesian meta-analysis with an informative prior for heterogeneity. © 2015 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd. © 2015 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd.

  14. The PRISMA statement for reporting systematic reviews and meta-analysis of studies that evaluate health care interventions: explanation and elaboration

    Directory of Open Access Journals (Sweden)

    Alessandro Liberati

    2009-12-01

    Full Text Available Systematic reviews and meta-analyses are essential to summarize evidence relating to efficacy and safety of health care interventions accurately and reliably. The clarity and transparency of these reports, however, is not optimal. Poor reporting of systematic reviews diminishes their value to clinicians, policy makers, and other users. Since the development of the QUOROM (QUality Of Reporting Of Meta-analysis Statement—a reporting guideline published in 1999—there have been several conceptual, methodological, and practical advances regarding the conduct and reporting of systematic reviews and meta-analyses. Also, reviews of published systematic reviews have found that key information about these studies is often poorly reported. Realizing these issues, an international group that included experienced authors and methodologists developed PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses as an evolution of the original QUOROM guideline for systematic reviews and meta-analyses of evaluations of health care interventions. The PRISMA Statement consists of a 27-item checklist and a four-phase flow diagram. The checklist includes items deemed essential for transparent reporting of a systematic review. In this Explanation and Elaboration document, we explain the meaning and rationale for each checklist item. For each item, we include an example of good reporting and, where possible, references to relevant empirical studies and methodological literature. The PRISMA Statement, this document, and the associated Web site (http://www. prisma-statement.org/ should be helpful resources to improve reporting of systematic reviews and meta-analyses.

  15. Hyperhomocysteinemia, methylenetetrahydrofolate reductase c.677C>T polymorphism and risk of cancer: cross-sectional and prospective studies and meta-analyses of 75,000 cases and 93,000 controls

    DEFF Research Database (Denmark)

    Zacho, Jeppe; Yazdanyar, Shiva; Bojesen, Stig E;

    2011-01-01

    Global DNA hypomethylation associates with development of cancer. DNA hypomethylation also associates with hyperhomocysteinemia and MTHFR c.677C>T homozygosity, both of which may associate with increased risk of cancer. We tested the putative association of hyperhomocysteinemia with cancer and th...

  16. A Statistical Perspective on the Design of Drug-Court Studies

    Science.gov (United States)

    Merrall, Elizabeth L. C.; Bird, Sheila M.

    2009-01-01

    Recent meta-analyses of drug-court studies recognized the poor methodological quality of the evaluations, with only a few being randomized. This article critiques the design of the randomized studies from a statistical perspective. Learning points are identified for future drug-court studies and are applicable to evaluations both of other…

  17. 《中华创伤骨科杂志》发表的Meta分析/系统评价的报告及方法学质量评价%Assessment of reporting and methodological quality of meta-analyses/systematic reviews published in Chinese Journal of Orthopaedic Trauma

    Institute of Scientific and Technical Information of China (English)

    丁凡; 任义军; 赵志明; 胡锐; 李明静; 勘武生

    2015-01-01

    Objective To assess the reporting and methodological quality of meta-analyses(MA) and systematic reviews(SR) published in Chinese Journal of Orthopaedic Trauma.Methods The MA/SR published in Chinese Journal of Orthopaedic Trauma from September 1999 to December 2013 were searched for via Wanfang Database and by hand.Two investigators screened documents independently according to inclusion and exclusion criteria.Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) and Assessment of Multiple Systematic Reviews (AMSTAR) Scales were used to evaluate the reporting and methodological quality of cited studies around 2010.Statistical analysis was performed using SPSS 20.0.Results Twenty-three MA/SR studies were identified.Their average PRISMA score was 20.7 ±2.3 (range,from 15 to 26).As for the reporting quality,severe flaws were identified in one study(4.3%),moderate flaws in 12 studies(52.2%) and mild flaws in 10(43.5%).The average AMSTAR score was 6.2 ± 1.4 (range,from 3 to 8).The methodological quality was graded as low in 2 (8.7%) and as fair in 21 (91.3%) studies.The PRISMA score (20.7 ±2.8) and the AMSTAR score (6.3 ± 1.4) of MA/SR published after 2010 were insignificantly higher than those before 2010 (20.6 ± 1.6 and 6.0 ± 1.5 respectively) (P > 0.05).The reporting flaws lay in the items of Protocol and Registration,Study Selection,Risk of Bias across Studies,Additional Analysis and Funding.The main methodological flaws involved Priori Design,Publication Status,Assessment of Publication Bias and Statement of Conflict of Interest.Conclusions Since the quality of MA/SR published in Chinese Journal of Orthopaedic Trauma was generally fair,the MA/ SR studies might have provide reliable evidence for clinical practice.Their reporting and methodological quality,however,deserves to be improved.%目的 评价《中华创伤骨科杂志》公开发表的Meta分析(MA)/系统评价(SR)的报告质量及方法学质量.方法

  18. Content Analysis of Meta-Analytic Studies from I/O Psychology.

    Science.gov (United States)

    Cornwell, John M.

    The use of meta-analysis in industrial and organizational psychology has become quite common. Unfortunately, the understanding and research necessary to ensure appropriate application of the technique have not been as widespread. As part of a larger study, a content analysis of meta-analyses from the industrial and organizational psychological…

  19. Psychotherapy for Depression in Adults: A Meta-Analysis of Comparative Outcome Studies

    Science.gov (United States)

    Cuijpers, Pim; van Straten, Annemieke; Andersson, Gerhard; van Oppen, Patricia

    2008-01-01

    Although the subject has been debated and examined for more than 3 decades, it is still not clear whether all psychotherapies are equally efficacious. The authors conducted 7 meta-analyses (with a total of 53 studies) in which 7 major types of psychological treatment for mild to moderate adult depression (cognitive-behavior therapy, nondirective…

  20. Large-Scale Gene-Centric Meta-Analysis across 39 Studies Identifies Type 2 Diabetes Loci

    NARCIS (Netherlands)

    Saxena, Richa; Elbers, Clara C.; Guo, Yiran; Peter, Inga; Gaunt, Tom R.; Mega, Jessica L.; Lanktree, Matthew B.; Tare, Archana; Almoguera Castillo, Berta; Li, Yun R.; Johnson, Toby; Bruinenberg, Marcel; Gilbert-Diamond, Diane; Rajagopalan, Ramakrishnan; Voight, Benjamin F.; Balasubramanyam, Ashok; Barnard, John; Bauer, Florianne; Baumert, Jens; Bhangale, Tushar; Boehm, Bernhard O.; Braund, Peter S.; Burton, Paul R.; Chandrupatla, Hareesh R.; Clarke, Robert; Cooper-DeHoff, Rhonda M.; Crook, Errol D.; Davey-Smith, George; Day, Ian N.; de Boer, Anthonius; de Groot, Mark C. H.; Drenos, Fotios; Ferguson, Jane; Fox, Caroline S.; Furlong, Clement E.; Gibson, Quince; Gieger, Christian; Gilhuijs-Pederson, Lisa A.; Glessner, Joseph T.; Goel, Anuj; Gong, Yan; Grant, Struan F. A.; Grobbee, Diederick E.; Hastie, Claire; Humphries, Steve E.; Kim, Cecilia E.; Kivimaki, Mika; Kleber, Marcus; Meisinger, Christa; Kumari, Meena; Langaee, Taimour Y.; Lawlor, Debbie A.; Li, Mingyao; Lobmeyer, Maximilian T.; Maitland-van der Zee, Anke-Hilse; Meijs, Matthijs F. L.; Molony, Cliona M.; Morrow, David A.; Murugesan, Gurunathan; Musani, Solomon K.; Nelson, Christopher P.; Newhouse, Stephen J.; O'Connell, Jeffery R.; Padmanabhan, Sandosh; Palmen, Jutta; Patel, Sanjey R.; Pepine, Carl J.; Pettinger, Mary; Price, Thomas S.; Rafelt, Suzanne; Ranchalis, Jane; Rasheed, Asif; Rosenthal, Elisabeth; Ruczinski, Ingo; Shah, Sonia; Shen, Haiqing; Silbernagel, Guenther; Smith, Erin N.; Spijkerman, Annemieke W. M.; Stanton, Alice; Steffes, Michael W.; Thorand, Barbara; Trip, Mieke; van der Harst, Pim; van der A, Daphne L.; van Iperen, Erik P. A.; van Setten, Jessica; van Vliet-Ostaptchouk, Jana V.; Verweij, Niek; Wolffenbuttel, Bruce H. R.; Young, Taylor; Zafarmand, M. Hadi; Zmuda, Joseph M.; Boehnke, Michael; Altshuler, David; McCarthy, Mark; Kao, W. H. Linda; Pankow, James S.; Cappola, Thomas P.; Sever, Peter; Poulter, Neil; Caulfield, Mark; Dominiczak, Anna; Shields, Denis C.; Bhatt, Deepak L.; Zhang, Li; Curtis, Sean P.; Danesh, John; Casas, Juan P.; van der Schouw, Yvonne T.; Onland-Moret, N. Charlotte; Doevendans, Pieter A.; Dorn, Gerald W.; Farrall, Martin; FitzGerald, Garret A.; Hamsten, Anders; Hegele, Robert; Hingorani, Aroon D.; Hofker, Marten H.; Huggins, Gordon S.; Illig, Thomas; Jarvik, Gail P.; Johnson, Julie A.; Klungel, Olaf H.; Knowler, William C.; Koenig, Wolfgang; Maerz, Winfried; Meigs, James B.; Melander, Olle; Munroe, Patricia B.; Mitchell, Braxton D.; Bielinski, Susan J.; Rader, Daniel J.; Reilly, Muredach P.; Rich, Stephen S.; Rotter, Jerome I.; Saleheen, Danish; Samani, Nilesh J.; Schadt, Eric E.; Shuldiner, Alan R.; Silverstein, Roy; Kottke-Marchant, Kandice; Talmud, Philippa J.; Watkins, Hugh; Asselbergs, Folkert W.; de Bakker, Paul I. W.; McCaffery, Jeanne; Wijmenga, Cisca; Sabatine, Marc S.; Wilson, James G.; Reiner, Alex; Bowden, Donald W.; Hakonarson, Hakon; Siscovick, David S.; Keating, Brendan J.

    2012-01-01

    To identify genetic factors contributing to type 2 diabetes (T2D), we performed large-scale meta-analyses by using a custom similar to 50,000 SNP genotyping array (the ITMAT-Broad-CARe array) with similar to 2000 candidate genes in 39 multiethnic population-based studies, case-control studies, and c

  1. Intrinsic Motivation and Creativity Related to Product: A Meta-Analysis of the Studies Published between 1990-2010

    Science.gov (United States)

    de Jesus, Saul Neves; Rus, Claudia Lenuta; Lens, Willy; Imaginário, Susana

    2013-01-01

    Although the relationship between motivation (especially intrinsic motivation) and creativity (especially as a product), no meta-analyses have been conducted on the relationship between these 2 concepts. This study aimed to analyze the relationship between intrinsic motivation and creativity related to product (i.e., creative outcomes) through…

  2. 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

  3. Genome-wide association studies identify CHRNA5/3 and HTR4 in the development of airflow obstruction

    NARCIS (Netherlands)

    Wilk, Jemma B; Shrine, Nick R G; Loehr, Laura R; Zhao, Jing Hua; Manichaikul, Ani; Lopez, Lorna M; Smith, Albert Vernon; Heckbert, Susan R; Smolonska, Joanna; Tang, Wenbo; Loth, Daan W; Curjuric, Ivan; Hui, Jennie; Cho, Michael H; Latourelle, Jeanne C; Henry, Amanda P; Aldrich, Melinda; Bakke, Per; Beaty, Terri H; Bentley, Amy R; Borecki, Ingrid B; Brusselle, Guy G; Burkart, Kristin M; Chen, Ting-hsu; Couper, David; Crapo, James D; Davies, Gail; Dupuis, Josée; Franceschini, Nora; Gulsvik, Amund; Hancock, Dana B; Harris, Tamara B; Hofman, Albert; Imboden, Medea; James, Alan L; Khaw, Kay-Tee; Lahousse, Lies; Launer, Lenore J; Litonjua, Augusto; Liu, Yongmei; Lohman, Kurt K; Lomas, David A; Lumley, Thomas; Marciante, Kristin D; McArdle, Wendy L; Meibohm, Bernd; Morrison, Alanna C; Musk, Arthur W; Myers, Richard H; North, Kari E; Postma, Dirkje S; Psaty, Bruce M; Rich, Stephen S; Rivadeneira, Fernando; Rochat, Thierry; Rotter, Jerome I; Artigas, María Soler; Starr, John M; Uitterlinden, André G; Wareham, Nicholas J; Wijmenga, Cisca; Zanen, Pieter; Province, Michael A; Silverman, Edwin K; Deary, Ian J; Palmer, Lyle J; Cassano, Patricia A; Gudnason, Vilmundur; Barr, R Graham; Loos, Ruth J F; Strachan, David P; London, Stephanie J; Boezen, Hendrika; Probst-Hensch, Nicole; Gharib, Sina A; Hall, Ian P; O'Connor, George T; Tobin, Martin D; Stricker, Bruno H

    2012-01-01

    RATIONALE: Genome-wide association studies (GWAS) have identified loci influencing lung function, but fewer genes influencing chronic obstructive pulmonary disease (COPD) are known. OBJECTIVES: Perform meta-analyses of GWAS for airflow obstruction, a key pathophysiologic characteristic of COPD asses

  4. Calcium intake and risk of hip fracture in men and women a meta-analysis of prospective cohort studies and randomized controlled trials

    Science.gov (United States)

    The role of total calcium intake for the prevention of hip fracture risk has not been well established. The objective of this analysis was to assess the relation of calcium intake to risk of hip fracture based on meta-analyses of cohort studies and clinical trials. In cohort studies in women (7 stu...

  5. Effects of low-dose versus placebo or conventional-dose postmenopausal hormone therapy on variables related to cardiovascular risk: a systematic review and meta-analyses of randomized clinical trials.

    Science.gov (United States)

    Casanova, Gislaine; Bossardi Ramos, Ramon; Ziegelmann, Patrícia; Spritzer, Poli Mara

    2015-03-01

    Hormone therapy (HT), the most efficient treatment for menopausal symptoms, might have deleterious cardiovascular (CV) effects. This study aimed to evaluate the effects of low-dose estrogen HT on CV risk factors vs conventional-dose HT and placebo in postmenopausal women with no established CV disease. MEDLINE, Cochrane Central, and EMBASE were searched for trials published in 1990-2013; a hand search of reference lists of selected articles was performed; and ClinicalTrials.gov was searched for unpublished trials. Within randomized controlled trials of healthy postmenopausal women comparing low-dose HT to placebo or conventional-dose HT, 11 418 studies were initially identified. Data were independently extracted by two investigators. Disagreements were resolved by a third author. Twenty-eight trials (3360 patients) were included. Low-dose HT vs placebo or conventional-dose HT did not effect weight, body mass index (BMI), blood pressure, C-reactive protein, or high-density lipoprotein cholesterol (HDL-C). Low-dose HT was associated with lower levels of total cholesterol (-12.16 mg/dL, 95% confidence interval [CI], -17.41 - -6.92) and low-density lipoprotein cholesterol (LDL-C) (-12.16 mg/dL; 95% CI, -16.55 - -7.77) vs placebo. Compared with conventional-dose HT, low-dose HT was associated with higher total cholesterol (5.05 mg/dL; 95% CI, 0.88-9.21) and LDL-C (4.49 mg/dL; 95% CI, 0.59-8.39). Low-dose HT was not associated with differences in triglycerides vs placebo. Oral, low-dose HT was associated with lower triglycerides vs conventional-dose HT (-14.09 mg/dL; 95% CI, -24.2 - -3.93). In this population of apparently healthy postmenopausal women, the effect of low-dose HT did not differ from that of placebo or conventional-dose HT regarding weight, BMI, blood pressure, CRP, or HDL-C. In contrast, low-dose HT was associated with better lipid profile vs placebo, and induced higher total and LDL-C and lower triglycerides vs conventional-dose HT.

  6. The Energy Content and Composition of Meals Consumed after an Overnight Fast and Their Effects on Diet Induced Thermogenesis: A Systematic Review, Meta-Analyses and Meta-Regressions

    Directory of Open Access Journals (Sweden)

    Angelica Quatela

    2016-10-01

    Full Text Available This systematic review investigated the effects of differing energy intakes, macronutrient compositions, and eating patterns of meals consumed after an overnight fast on Diet Induced Thermogenesis (DIT. The initial search identified 2482 records; 26 papers remained once duplicates were removed and inclusion criteria were applied. Studies (n = 27 in the analyses were randomized crossover designs comparing the effects of two or more eating events on DIT. Higher energy intake increased DIT; in a mixed model meta-regression, for every 100 kJ increase in energy intake, DIT increased by 1.1 kJ/h (p < 0.001. Meals with a high protein or carbohydrate content had a higher DIT than high fat, although this effect was not always significant. Meals with medium chain triglycerides had a significantly higher DIT than long chain triglycerides (meta-analysis, p = 0.002. Consuming the same meal as a single bolus eating event compared to multiple small meals or snacks was associated with a significantly higher DIT (meta-analysis, p = 0.02. Unclear or inconsistent findings were found by comparing the consumption of meals quickly or slowly, and palatability was not significantly associated with DIT. These findings indicate that the magnitude of the increase in DIT is influenced by the energy intake, macronutrient composition, and eating pattern of the meal.

  7. The Energy Content and Composition of Meals Consumed after an Overnight Fast and Their Effects on Diet Induced Thermogenesis: A Systematic Review, Meta-Analyses and Meta-Regressions.

    Science.gov (United States)

    Quatela, Angelica; Callister, Robin; Patterson, Amanda; MacDonald-Wicks, Lesley

    2016-10-25

    This systematic review investigated the effects of differing energy intakes, macronutrient compositions, and eating patterns of meals consumed after an overnight fast on Diet Induced Thermogenesis (DIT). The initial search identified 2482 records; 26 papers remained once duplicates were removed and inclusion criteria were applied. Studies (n = 27) in the analyses were randomized crossover designs comparing the effects of two or more eating events on DIT. Higher energy intake increased DIT; in a mixed model meta-regression, for every 100 kJ increase in energy intake, DIT increased by 1.1 kJ/h (p < 0.001). Meals with a high protein or carbohydrate content had a higher DIT than high fat, although this effect was not always significant. Meals with medium chain triglycerides had a significantly higher DIT than long chain triglycerides (meta-analysis, p = 0.002). Consuming the same meal as a single bolus eating event compared to multiple small meals or snacks was associated with a significantly higher DIT (meta-analysis, p = 0.02). Unclear or inconsistent findings were found by comparing the consumption of meals quickly or slowly, and palatability was not significantly associated with DIT. These findings indicate that the magnitude of the increase in DIT is influenced by the energy intake, macronutrient composition, and eating pattern of the meal.

  8. Cardiovascular Disease Prfevention: from meta-analyses to life expectancies

    NARCIS (Netherlands)

    O.H. Franco (Oscar)

    2005-01-01

    textabstractCardiovascular Disease (CVD) includes dysfunctional conditions of the heart and of the blood vessel system (arteries, veins, and capillaries) that among other functions supply oxygen to all body tissues and organs, including vital life-sustaining areas like the brain and the heart its

  9. The limited informativeness of meta-analyses and media effects

    NARCIS (Netherlands)

    Valkenburg, P.M.

    2015-01-01

    In this issue of Perspectives on Psychological Science, Christopher Ferguson reports on a meta-analysis examining the relationship between children’s video game use and several outcome variables, including aggression and attention deficit symptoms (Ferguson, 2015, this issue). In this commentary, I

  10. Systematic Reviews and Meta-analyses for Cardiology Fellows.

    Science.gov (United States)

    Fares, Munes; Alahdab, Fares; Alsaied, Tarek

    2016-07-01

    Participating in a scholarly activity is one of the training requirements for cardiology fellows. However, it can be very challenging to complete a research project during such a busy period of clinical training. To help the cardiology fellows in choosing and starting off a research project, a light has been shed on the process of conducting a systematic review, and the importance of this research activity, as well as its limitations. © 2016 Wiley Periodicals, Inc.

  11. The genetic aetiology of cannabis use initiation: A meta-analysis of genome-wide association studies and a SNP-based heritability estimation

    NARCIS (Netherlands)

    Verweij, C.J.H.; Vinkhuyzen, A.A.E.; Benyamin, B.; Lynskey, M.T.; Quaye, L.; Agrawal, A.; Gordon, S.D.; Montgomery, G.W.; Madden, P.A.F.; Heath, A.C.; Spector, T.D.; Martin, N.G.; Medland, S.E.

    2013-01-01

    While initiation of cannabis use is around 40% heritable, not much is known about the underlying genetic aetiology. Here, we meta-analysed two genome-wide association studies of initiation of cannabis use with >10000 individuals. None of the genetic variants reached genome-wide significance. We a

  12. Genome-wide association study for refractive astigmatism reveals genetic co-determination with spherical equivalent refractive error: the CREAM consortium

    NARCIS (Netherlands)

    Q. Li (Qing); R. Wojciechowski (Robert); C.L. Simpson (Claire); P.G. Hysi (Pirro); V.J.M. Verhoeven (Virginie); M.K. Ikram (Kamran); R. Höhn (René); V. Vitart (Veronique); A.W. Hewit (Alex); K. Oexle (Konrad); K.M. Makela (Kari Matti); S. MacGregor (Stuart); M. Pirastu (Mario); Q. Fan (Qiao); C-Y. Cheng (Ching-Yu); B. St Pourcain (Beate); G. Mcmahon (George); J.P. Kemp (John); K. Northstone (Kate); J.S. Rahi (Jugnoo); P. Cumberland (Phillippa); N.G. Martin (Nicholas); P.G. Sanfilippo (Paul G.); Y. Lu (Yi); Y. Wang (Ying); C. Hayward (Caroline); O. Polasek (Ozren); H. Campbell (Harry); G. Bencic (Goran); A. Wright (Alan); J. Wedenoja (Juho); T. Zeller (Tanja); A. Schillert (Arne); A. Mirshahi (Alireza); K.J. Lackner (Karl); S.P. Yip (Shea Ping); M.K.H. Yap (Maurice K. H.); J.S. Ried (Janina); C. Gieger (Christian); D. Murgia (Daniela); J.F. Wilson (James F); B.W. Fleck (Brian W.); S. Yazar (Seyhan); J.R. Vingerling (Hans); A. Hofman (Albert); A.G. Uitterlinden (André); F. Rivadeneira Ramirez (Fernando); N. Amin (Najaf); L.C. Karssen (Lennart); B.A. Oostra (Ben); X. Zhou (Xin); Y.Y. Teo (Yik Ying); E.S. Tai (Shyong); E.N. Vithana (Eranga); V.A. Barathi (Veluchamy); Y. Zheng (Yingfeng); R. Siantar (Rosalynn); K. Neelam (Kumari); Y. Shin (Youchan); J. Lam (Janice); E. Yonova-Doing (Ekaterina); C. Venturini (Cristina); S.M. Hosseini (S Mohsen); H.-S. Wong (Hoi-Suen); T. Lehtimäki (Terho); M. Kähönen (Mika); O. Raitakari (Olli); N. Timpson (Nicholas); D.M. Evans (David M.); C.C. Khor; T. Aung (Tin); T.L. Young (Terri); P. Mitchell (Paul); B.E.K. Klein (Barbara); C.M. van Duijn (Cock); T. Meitinger (Thomas); J.B. Jonas (Jost B.); P.N. Baird (Paul); D.A. Mackey (David); T.Y. Wong (Tien); S-M. Saw (Seang-Mei); O. Pärssinen (Olavi); D.E. Stambolian (Dwight); C.J. Hammond (Christopher); C.C.W. Klaver (Caroline); C. Williams (Cathy); A.D. Paterson (Andrew); J.E. Bailey-Wilson (Joan E.); J. Guggenheim (Jean)

    2015-01-01

    textabstractTo identify genetic variants associated with refractive astigmatism in the general population, meta-analyses of genome-wide association studies were performed for: White Europeans aged at least 25 years (20 cohorts, N = 31,968); Asian subjects aged at least 25 years (7 cohorts, N = 9,295

  13. Multi-stage genome-wide association study identifies new susceptibility locus for testicular germ cell tumour on chromosome 3q25

    DEFF Research Database (Denmark)

    Litchfield, Kevin; Sultana, Razvan; Renwick, Anthony

    2015-01-01

    Recent genome-wide association studies (GWAS) and subsequent meta-analyses have identified over 25 SNPs at 18 loci, together accounting for >15% of the genetic susceptibility to testicular germ cell tumour (TGCT). To identify further common SNPs associated with TGCT, here we report a three-stage ...

  14. Association between study design and citation counts of articles published in the American Journal of Orthodontics and Dentofacial Orthopedics and Angle Orthodontist.

    Science.gov (United States)

    Allareddy, Veerasathpurush; Lee, Min Kyeong; Shah, Andrea; Elangovan, Satheesh; Lin, Chin-Yu

    2012-01-01

    The scientific community views meta-analyses and systematic reviews, in addition to well-designed randomized controlled clinical trials, as the highest echelon in the continuum of hierarchy of evidence. The objective of this study was to examine the association between different study designs and citation counts of articles published in the American Journal of Orthodontics and Dentofacial Orthopedics and Angle Orthodontist. All articles, excluding editorial comments, letters to the editor, commentaries, and special articles, that were published in the American Journal of Orthodontics and Dentofacial Orthopedics and Angle Orthodontist during the years 2004 and 2005 were examined in this study. The number of times an article was cited in the first 24 months after its publication was computed. The PubMed database was used to index the study design of the articles. The association between study design and citation counts was examined using the Kruskal-Wallis test. A multivariable negative binomial regression model was used to examine the association between citation count and study design along with several other confounding variables. A total of 624 articles were selected for analysis. Of these, there were 25 meta-analyses or review articles, 42 randomized clinical trials, 59 clinical trials, 48 animal studies, 64 case reports, and 386 quasiexperimental/miscellaneous study designs. The mean ± SD citation count was 1.04 ± 1.46. Nearly half of the articles (n = 311) were not cited even once during the observation period. Case reports were cited less frequently than meta-analyses or reviews (incident risk ratio, 0.37; 95% confidence interval, 0.19 to 0.72; P = .003), even after adjusting for other independent variables. Among various study designs, meta-analyses and review articles are more likely to be cited in the first 24 months after publication. This study demonstrates the importance of publishing more meta-analyses and review articles for quicker dissemination of

  15. Meta-analysis of observational epidemiological studies: a review.

    OpenAIRE

    Jones, D R

    1992-01-01

    Meta-analyses (integration of findings by quantitative analyses of results of individual studies) are already widely used in the psychological and educational sciences and in the pooling of clinical trial results. Examples of the application of such techniques to the results of observational epidemiological studies are now proliferating. In this paper meta-analysis of the results of observational epidemiological studies is reviewed. Uncritical adoption of techniques used in pooled analyses of...

  16. Sample size calculation for meta-epidemiological studies.

    Science.gov (United States)

    Giraudeau, Bruno; Higgins, Julian P T; Tavernier, Elsa; Trinquart, Ludovic

    2016-01-30

    Meta-epidemiological studies are used to compare treatment effect estimates between randomized clinical trials with and without a characteristic of interest. To our knowledge, there is presently nothing to help researchers to a priori specify the required number of meta-analyses to be included in a meta-epidemiological study. We derived a theoretical power function and sample size formula in the framework of a hierarchical model that allows for variation in the impact of the characteristic between trials within a meta-analysis and between meta-analyses. A simulation study revealed that the theoretical function overestimated power (because of the assumption of equal weights for each trial within and between meta-analyses). We also propose a simulation approach that allows for relaxing the constraints used in the theoretical approach and is more accurate. We illustrate that the two variables that mostly influence power are the number of trials per meta-analysis and the proportion of trials with the characteristic of interest. We derived a closed-form power function and sample size formula for estimating the impact of trial characteristics in meta-epidemiological studies. Our analytical results can be used as a 'rule of thumb' for sample size calculation for a meta-epidemiologic study. A more accurate sample size can be derived with a simulation study.

  17. Meta-analysis of data from animal studies: a practical guide.

    Science.gov (United States)

    Vesterinen, H M; Sena, E S; Egan, K J; Hirst, T C; Churolov, L; Currie, G L; Antonic, A; Howells, D W; Macleod, M R

    2014-01-15

    Meta-analyses of data from human studies are invaluable resources in the life sciences and the methods to conduct these are well documented. Similarly there are a number of benefits in conducting meta-analyses on data from animal studies; they can be used to inform clinical trial design, or to try and explain discrepancies between preclinical and clinical trial results. However there are inherit differences between animal and human studies and so applying the same techniques for the meta-analysis of preclinical data is not straightforward. For example preclinical studies are frequently small and there is often substantial heterogeneity between studies. This may have an impact on both the method of calculating an effect size and the method of pooling data. Here we describe a practical guide for the meta-analysis of data from animal studies including methods used to explore sources of heterogeneity.

  18. Music-based interventions in palliative cancer care: a review of quantitative studies and neurobiological literature

    OpenAIRE

    Archie, Patrick; Bruera, Eduardo; Cohen, Lorenzo

    2013-01-01

    Purpose This study aimed to review quantitative literature pertaining to studies of music-based interventions in palliative cancer care and to review the neurobiological literature that may bare relevance to the findings from these studies. Methods A narrative review was performed, with particular emphasis on RCTs, meta-analyses, and systematic reviews. The Cochrane Library, Ovid, PubMed, CINAHL Plus, PsycINFO, and ProQuest were searched for the subject headings music, music therapy, cancer, ...

  19. Anorexia nervosa is linked to reduced brain structure in reward and somatosensory regions: a meta-analysis of VBM studies.

    Science.gov (United States)

    Titova, Olga E; Hjorth, Olof C; Schiöth, Helgi B; Brooks, Samantha J

    2013-04-09

    Structural imaging studies demonstrate brain tissue abnormalities in eating disorders, yet a quantitative analysis has not been done. In global and regional meta-analyses of 9 voxel-based morphometry (VBM) studies, with a total of 228 eating disorder participants (currently ill with anorexia nervosa), and 240 age-matched healthy controls, we compare brain volumes using global and regional analyses. Anorexia nervosa (AN) patients have global reductions in gray (effect size = -0.66) and white matter (effect size = -0.74) and increased cerebrospinal fluid (effect size = 0.98) and have regional decreases in left hypothalamus, left inferior parietal lobe, right lentiform nucleus and right caudate, and no significant increases. No significant difference in hemispheric lateralization was found. Global and regional meta-analyses suggest that excessive restrained eating as found in those with anorexia nervosa coincides with structural brain changes analogous to clinical symptoms.

  20. Quality Assessment of Studies Published in Open Access and Subscription Journals: Results of a Systematic Evaluation.

    Directory of Open Access Journals (Sweden)

    Roberta Pastorino

    Full Text Available Along with the proliferation of Open Access (OA publishing, the interest for comparing the scientific quality of studies published in OA journals versus subscription journals has also increased. With our study we aimed to compare the methodological quality and the quality of reporting of primary epidemiological studies and systematic reviews and meta-analyses published in OA and non-OA journals.In order to identify the studies to appraise, we listed all OA and non-OA journals which published in 2013 at least one primary epidemiologic study (case-control or cohort study design, and at least one systematic review or meta-analysis in the field of oncology. For the appraisal, we picked up the first studies published in 2013 with case-control or cohort study design from OA journals (Group A; n = 12, and in the same time period from non-OA journals (Group B; n = 26; the first systematic reviews and meta-analyses published in 2013 from OA journals (Group C; n = 15, and in the same time period from non-OA journals (Group D; n = 32. We evaluated the methodological quality of studies by assessing the compliance of case-control and cohort studies to Newcastle and Ottawa Scale (NOS scale, and the compliance of systematic reviews and meta-analyses to Assessment of Multiple Systematic Reviews (AMSTAR scale. The quality of reporting was assessed considering the adherence of case-control and cohort studies to STrengthening the Reporting of OBservational studies in Epidemiology (STROBE checklist, and the adherence of systematic reviews and meta-analyses to Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA checklist.Among case-control and cohort studies published in OA and non-OA journals, we did not observe significant differences in the median value of NOS score (Group A: 7 (IQR 7-8 versus Group B: 8 (7-9; p = 0.5 and in the adherence to STROBE checklist (Group A, 75% versus Group B, 80%; p = 0.1. The results did not change after

  1. Quality Assessment of Studies Published in Open Access and Subscription Journals: Results of a Systematic Evaluation.

    Science.gov (United States)

    Pastorino, Roberta; Milovanovic, Sonja; Stojanovic, Jovana; Efremov, Ljupcho; Amore, Rosarita; Boccia, Stefania

    2016-01-01

    Along with the proliferation of Open Access (OA) publishing, the interest for comparing the scientific quality of studies published in OA journals versus subscription journals has also increased. With our study we aimed to compare the methodological quality and the quality of reporting of primary epidemiological studies and systematic reviews and meta-analyses published in OA and non-OA journals. In order to identify the studies to appraise, we listed all OA and non-OA journals which published in 2013 at least one primary epidemiologic study (case-control or cohort study design), and at least one systematic review or meta-analysis in the field of oncology. For the appraisal, we picked up the first studies published in 2013 with case-control or cohort study design from OA journals (Group A; n = 12), and in the same time period from non-OA journals (Group B; n = 26); the first systematic reviews and meta-analyses published in 2013 from OA journals (Group C; n = 15), and in the same time period from non-OA journals (Group D; n = 32). We evaluated the methodological quality of studies by assessing the compliance of case-control and cohort studies to Newcastle and Ottawa Scale (NOS) scale, and the compliance of systematic reviews and meta-analyses to Assessment of Multiple Systematic Reviews (AMSTAR) scale. The quality of reporting was assessed considering the adherence of case-control and cohort studies to STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) checklist, and the adherence of systematic reviews and meta-analyses to Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) checklist. Among case-control and cohort studies published in OA and non-OA journals, we did not observe significant differences in the median value of NOS score (Group A: 7 (IQR 7-8) versus Group B: 8 (7-9); p = 0.5) and in the adherence to STROBE checklist (Group A, 75% versus Group B, 80%; p = 0.1). The results did not change after adjustment

  2. Borrowing of strength and study weights in multivariate and network meta-analysis.

    Science.gov (United States)

    Jackson, Dan; White, Ian R; Price, Malcolm; Copas, John; Riley, Richard D

    2015-11-06

    Multivariate and network meta-analysis have the potential for the estimated mean of one effect to borrow strength from the data on other effects of interest. The extent of this borrowing of strength is usually assessed informally. We present new mathematical definitions of 'borrowing of strength'. Our main proposal is based on a decomposition of the score statistic, which we show can be interpreted as comparing the precision of estimates from the multivariate and univariate models. Our definition of borrowing of strength therefore emulates the usual informal assessment. We also derive a method for calculating study weights, which we embed into the same framework as our borrowing of strength statistics, so that percentage study weights can accompany the results from multivariate and network meta-analyses as they do in conventional univariate meta-analyses. Our proposals are illustrated using three meta-analyses involving correlated effects for multiple outcomes, multiple risk factor associations and multiple treatments (network meta-analysis). © The Author(s) 2015.

  3. Invited review: Recommendations for reporting intervention studies on reproductive performance in dairy cattle: Improving design, analysis, and interpretation of research on reproduction.

    Science.gov (United States)

    Lean, Ian J; Lucy, Matthew C; McNamara, John P; Bradford, Barry J; Block, Elliot; Thomson, Jennifer M; Morton, John M; Celi, Pietro; Rabiee, Ahmad R; Santos, José E P; Thatcher, William W; LeBlanc, Stephen J

    2016-01-01

    Abundant evidence from the medical, veterinary, and animal science literature demonstrates that there is substantial room for improvement of the clarity, completeness, and accuracy of reporting of intervention studies. More rigorous reporting guidelines are needed to improve the quality of data available for use in comparisons of outcomes (or meta-analyses) of multiple studies. Because of the diversity of factors that affect reproduction and the complexity of interactions between these, a systematic approach is required to design, conduct, and analyze basic and applied studies of dairy cattle reproduction. Greater consistency, clarity, completeness, and correctness of design and reporting will improve the value of each report and allow for greater depth of evaluation in meta-analyses. Each of these benefits will improve understanding and application of current knowledge and better identify questions that require additional modeling or primary research. The proposed guidelines and checklist will aid in the design, conduct, analysis, and reporting of intervention studies. We propose an adaptation of the REFLECT (Reporting Guidelines for Randomized Controlled Trials for Livestock and Food Safety) statement to provide guidelines and a checklist specific to reporting intervention studies in dairy cattle reproduction. Furthermore, we provide recommendations that will assist investigators to produce studies with greater internal and external validity that can more often be included in systematic reviews and global meta-analyses. Such studies will also assist the development of models to describe the physiology of reproduction.

  4. Continous controversy about radiation oncologists' choice of treatment regimens for bone metatases: should we blame doctors, canser-related features, or design of previous clinical studies

    OpenAIRE

    Nieder, Carsten; Pawinski, Adam; Dalhaug, Astrid

    2013-01-01

    Recent studies from Italy, Japan and Norway have confirmed previous reports, which found that a large variety of palliative radiotherapy regimens are used for painful bone metastases. Routine use of single fraction treatment might or might not be the preferred institutional approach. It is not entirely clear why inter-physician and inter-institution differences continue to persist despite numerous randomized trials, meta-analyses and guidelines, which recommend against more costly and inconve...

  5. PEDro or Cochrane to Assess the Quality of Clinical Trials? A Meta-Epidemiological Study.

    Directory of Open Access Journals (Sweden)

    Susan Armijo-Olivo

    Full Text Available There is debate on how the methodological quality of clinical trials should be assessed. We compared trials of physical therapy (PT judged to be of adequate quality based on summary scores from the Physiotherapy Evidence Database (PEDro scale with trials judged to be of adequate quality by Cochrane Risk of Bias criteria.Meta-epidemiological study within Cochrane Database of Systematic Reviews.Meta-analyses of PT trials were identified in the Cochrane Database of Systematic Reviews. For each trial PeDro and Cochrane assessments were extracted from the PeDro and Cochrane databases. Adequate quality was defined as adequate generation of random sequence, concealment of allocation, and blinding of outcome assessors (Cochrane criteria or as trials with a PEDro summary score ≥5 or ≥6 points. We combined trials of adequate quality using random-effects meta-analysis.Forty-one Cochrane reviews and 353 PT trials were included. All meta-analyses included trials with PEDro scores ≥5, 37 (90.2% included trials with PEDro scores ≥6 and only 22 (53.7% meta-analyses included trials of adequate quality according to the Cochrane criteria. Agreement between PeDro and Cochrane was poor for PeDro scores of ≥5 points (kappa = 0.12; 95% CI 0.07 to 0.16 and slight for ≥6 points (kappa 0.24; 95% CI 0.16-0.32. When combining effect sizes of trials deemed to be of adequate quality according to PEDro or Cochrane criteria, we found that a substantial difference in the combined effect size (≥0.15 was evident in 9 (22% out of the 41 meta-analyses for PEDro cutoff ≥5 and 10 (24% for cutoff ≥6.The PeDro and Cochrane approaches lead to different sets of trials of adequate quality, and different combined treatment estimates from meta-analyses of these trials. A consistent approach to assessing RoB in trials of physical therapy should be adopted.

  6. Reaffirmed limitations of meta-analytic methods in the study of mild traumatic brain injury: a response to Rohling et al.

    Science.gov (United States)

    Bigler, Erin D; Farrer, Thomas J; Pertab, Jon L; James, Kelly; Petrie, Jo Ann; Hedges, Dawson W

    2013-01-01

    In 2009 Pertab, James, and Bigler published a critique of two prior meta-analyses by Binder, Rohling, and Larrabee (1997) and Frencham, Fox, and Maybery (2005) that showed small effect size difference at least 3 months post-injury in individuals who had sustained a mild traumatic brain injury (mTBI). The Binder et al. and Frencham et al. meta-analyses have been widely cited as showing no lasting effect of mTBI. In their critique Pertab et al. (2009) point out many limitations of these two prior meta-analyses, demonstrating that depending on how inclusion/exclusion criteria were defined different meta-analytic findings occur, some supporting the persistence of neuropsychological impairments beyond 3 months. Rohling et al. (2011) have now critiqued Pertab et al. (2009). Herein we respond to the Rolling et al. (2011) critique reaffirming the original findings of Pertab et al. (2009), providing additional details concerning the flaws in prior meta-analytic mTBI studies and the effects on neuropsychological performance.

  7. Reporting Quality of Systematic Reviews and Meta-analyses Published in Chinese Pediatric Journals: A Retrospective Study%国内儿科领域系统评价/Meta分析研究报告质量的回顾性分析

    Institute of Scientific and Technical Information of China (English)

    刘登瑞; 许家科; 麻婷; 谢雨桑; 胡芳; 李晓凤; 屈丽娜; 唐晓宇; 马彬

    2016-01-01

    目的 基于PRISMA和MOOSE清单对我国儿科领域所发表的不同类型系统评价/Meta分析(SR/MA)的报告质量现状及其存在的问题进行回顾性分析.方法 检索CSCD收录的国内7本儿科专科杂志,由两名评价者独立进行资料提取,分别基于PRISMA清单和MOOSE清单,判断纳入的干预性SR/MA和观察性SR/MA在各条目上的符合率,并交叉核对.根据被引频次、发表时间对清单各个条目的符合率进行亚组分析.使用SPSS 22.0进行统计分析,对分类资料采用例数(n)和百分比(%)进行统计描述,组间比较采用卡方检验.结果 共纳入SR/MA 157篇,包括干预性96篇,观察61篇.结果显示:①干预性SR/MA在PRISMA清单上的总体符合率较好,符合率超过50%的条目为20条(74.1%,20/27);观察性SR/MA在MOOSE清单上的总体符合率较低,低于50%的条目为15条(42.9%,15/35),更有20%的条目(7/35)符合率低于20%.②不同被引频次(≤5vs.>5)的SR/MA在PRISMA和MOOSE清单条目上的符合率并无太大区别,且在85.2% (23/27)和97.1% (34/35)的条目上无统计学差异;③随着PRISMA清单的引入和传播,干预性SR/MA在绝大多数条目上的符合率得到一定程度的提高,且在条目8、19、20、23差异有统计学意义(P≤0.05).结论 国内儿科领域SR/MA的数量呈现不断增长的趋势,且随着PRISMA清单的发布,国内儿科领域干预性SR/MA在PRISMA清单中的绝大部分条目上的符合率得到一定程度的提高,而观察性SR/MA在MOOSE清单上的总体符合率依然不高.因此,今后应更加关注该类研究质量的提高而非数量的增长.

  8. Perspective: NutriGrade: A Scoring System to Assess and Judge the Meta-Evidence of Randomized Controlled Trials and Cohort Studies in Nutrition Research.

    Science.gov (United States)

    Schwingshackl, Lukas; Knüppel, Sven; Schwedhelm, Carolina; Hoffmann, Georg; Missbach, Benjamin; Stelmach-Mardas, Marta; Dietrich, Stefan; Eichelmann, Fabian; Kontopanteils, Evangelos; Iqbal, Khalid; Aleksandrova, Krasimira; Lorkowski, Stefan; Leitzmann, Michael F; Kroke, Anja; Boeing, Heiner

    2016-11-01

    The objective of this study was to develop a scoring system (NutriGrade) to evaluate the quality of evidence of randomized controlled trial (RCT) and cohort study meta-analyses in nutrition research, building upon previous tools and expert recommendations. NutriGrade aims to assess the meta-evidence of an association or effect between different nutrition factors and outcomes, taking into account nutrition research-specific requirements not considered by other tools. In a pretest study, 6 randomly selected meta-analyses investigating diet-disease relations were evaluated with NutriGrade by 5 independent raters. After revision, NutriGrade was applied by the same raters to 30 randomly selected meta-analyses in the same thematic area. The reliability of ratings of NutriGrade items was calculated with the use of a multirater κ, and reliability of the total (summed scores) was calculated with the use of intraclass correlation coefficients (ICCs). The following categories for meta-evidence evaluation were established: high (8-10), moderate (6-7.99), low (4-5.99), and very low (0-3.99). The NutriGrade scoring system (maximum of 10 points) comprises the following items: 1) risk of bias, study quality, and study limitations, 2) precision, 3) heterogeneity, 4) directness, 5) publication bias, 6) funding bias, 7) study design, 8) effect size, and 9) dose-response. The NutriGrade score varied between 2.9 (very low meta-evidence) and 8.8 (high meta-evidence) for meta-analyses of RCTs, and it ranged between 3.1 and 8.8 for meta-analyses of cohort studies. The κ value of the ratings for each scoring item varied from 0.32 (95% CI: 0.22, 0.42) for risk of bias for cohort studies and 0.95 (95% CI: 0.91, 0.99) for study design, with a mean κ of 0.66 (95% CI: 0.53, 0.79). The ICC of the total score was 0.81 (95% CI: 0.69, 0.90). The NutriGrade scoring system showed good agreement and reliability. The initial findings regarding the performance of this newly established scoring system

  9. Bias and small-study effects influence treatment effect estimates: a meta-epidemiological study in oral medicine.

    Science.gov (United States)

    Papageorgiou, Spyridon N; Antonoglou, Georgios N; Tsiranidou, Elli; Jepsen, Søren; Jäger, Andreas

    2014-09-01

    To examine the influence of the following study characteristics on their study effect estimates: (1) indexing in MEDLINE, (2) language, and (3) design. For randomized trials, (4) trial size and (5) unequal randomization were also assessed. The CAtegorical Dental and Maxillofacial Outcome Syntheses meta-epidemiologic study was conducted. Eight databases/registers were searched up to September 2012 for meta-analyses of binary outcomes with at least five studies in the field of dental and maxillofacial medicine. The previously mentioned five study characteristics were investigated. The ratio of odds ratios (ROR) according to each characteristic was calculated with random-effects meta-regression and then pooled across meta-analyses. A total of 281 meta-analyses were identified and used to assess the influence of the following factors: non-MEDLINE indexing vs. MEDLINE indexing (n = 78; ROR, 1.12; 95% confidence interval [CI]: 1.05, 1.19; P = 0.001), language (n = 61; P = 0.546), design (n = 24; P = 0.576), small trials (<200 patients) vs. large trials (≥200 patients) (n = 80; ROR, 0.92; 95% CI: 0.87, 0.98; P = 0.009) and unequal randomization (n = 36; P = 0.828). Studies indexed in MEDLINE might present greater effects than non-indexed ones. Small randomized trials might present greater effects than large ones. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. How to understand the results of studies of glutamine supplementation.

    Science.gov (United States)

    Wernerman, Jan

    2015-11-03

    The lack of understanding of the mechanisms behind possible beneficial and possible harmful effects of glutamine supplementation makes the design of interventional studies of glutamine supplementations difficult, perhaps even hazardous. What is the interventional target, and how might it relate to outcomes? Taking one step further and aggregating results from interventional studies into meta-analyses does not diminish the difficulties. Therefore, conducting basic research seems to be a better idea than groping in the dark and exposing patients to potential harm in this darkness.

  11. Do health technology assessments comply with QUOROM diagram guidance? An empirical study.

    Science.gov (United States)

    Hind, Daniel; Booth, Andrew

    2007-11-20

    The Quality of Reporting of Meta-analyses (QUOROM) statement provides guidance for improving the quality of reporting of systematic reviews and meta-analyses. To make the process of study selection transparent it recommends "a flow diagram providing information about the number of RCTs identified, included, and excluded and the reasons for excluding them". We undertook an empirical study to identify the extent of compliance in the UK Health Technology Assessment (HTA) programme. We searched Medline to retrieve all systematic reviews of therapeutic interventions in the HTA monograph series published from 2001 to 2005. Two researchers recorded whether each study contained a meta-analysis of controlled trials, whether a QUOROM flow diagram was presented and, if so, whether it expressed the relationship between the number of citations and the number of studies. We used Cohen's kappa to test inter-rater reliability. 87 systematic reviews were retrieved. There was good and excellent inter-rater reliability for, respectively, whether a review contained a meta-analysis and whether each diagram contained a citation-to-study relationship. 49% of systematic reviews used a study selection flow diagram. When only systematic reviews containing a meta-analysis were analysed, compliance was only 32%. Only 20 studies (23% of all systematic reviews; 43% of those having a study selection diagram) had a diagram which expressed the relationship between citations and studies. Compliance with the recommendations of the QUOROM statement is not universal in systematic reviews or meta-analyses. Flow diagrams make the conduct of study selection transparent only if the relationship between citations and studies is clearly expressed. Reviewers should understand what they are counting: citations, papers, studies and trials are fundamentally different concepts which should not be confused in a diagram.

  12. Do health technology assessments comply with QUOROM diagram guidance? An empirical study

    Directory of Open Access Journals (Sweden)

    Booth Andrew

    2007-11-01

    Full Text Available Abstract Background The Quality of Reporting of Meta-analyses (QUOROM statement provides guidance for improving the quality of reporting of systematic reviews and meta-analyses. To make the process of study selection transparent it recommends "a flow diagram providing information about the number of RCTs identified, included, and excluded and the reasons for excluding them". We undertook an empirical study to identify the extent of compliance in the UK Health Technology Assessment (HTA programme. Methods We searched Medline to retrieve all systematic reviews of therapeutic interventions in the HTA monograph series published from 2001 to 2005. Two researchers recorded whether each study contained a meta-analysis of controlled trials, whether a QUOROM flow diagram was presented and, if so, whether it expressed the relationship between the number of citations and the number of studies. We used Cohen's kappa to test inter-rater reliability. Results 87 systematic reviews were retrieved. There was good and excellent inter-rater reliability for, respectively, whether a review contained a meta-analysis and whether each diagram contained a citation-to-study relationship. 49% of systematic reviews used a study selection flow diagram. When only systematic reviews containing a meta-analysis were analysed, compliance was only 32%. Only 20 studies (23% of all systematic reviews; 43% of those having a study selection diagram had a diagram which expressed the relationship between citations and studies. Conclusion Compliance with the recommendations of the QUOROM statement is not universal in systematic reviews or meta-analyses. Flow diagrams make the conduct of study selection transparent only if the relationship between citations and studies is clearly expressed. Reviewers should understand what they are counting: citations, papers, studies and trials are fundamentally different concepts which should not be confused in a diagram.

  13. Are larger effect sizes in experimental studies good predictors of higher citation rates?

    DEFF Research Database (Denmark)

    Schneider, Jesper Wiborg; Henriksen, Dorte

    2013-01-01

    Effect sizes are perhaps the most important quantitative information in statistical inferential studies. Recently, the hypothesis that rational citation behaviour in general ought to give credit to studies that successfully apply a treatment and detect greater effects, resulting in such studies...... areas and with a more credible model selection procedure. Using meta-analyses, we identify comparable individual experimental studies (n=259) from five different research specialties. Effect sizes are compared to the citation rates of the individual studies and impact factors for the journals where...

  14. Bias from historical control groups used in orthodontic research: a meta-epidemiological study.

    Science.gov (United States)

    Papageorgiou, Spyridon N; Koretsi, Vasiliki; Jäger, Andreas

    2017-02-01

    The validity of meta-analysis is dependent upon the quality of included studies. Here, we investigated whether the design of untreated control groups (i.e. source and timing of data collection) influences the results of clinical trials in orthodontic research. This meta-epidemiological study used unrestricted literature searching for meta-analyses in orthodontics including clinical trials with untreated control groups. Differences in standardized mean differences (ΔSMD) and their 95% confidence intervals (CIs) were calculated according to the untreated control group through multivariable random-effects meta-regression controlling for nature of the interventional group and study sample size. Effects were pooled with random-effects synthesis, followed by mixed-effect subgroup and sensitivity analyses. Studies with historical control groups reported deflated treatment effects compared to studies with concurrent control groups (13 meta-analyses; ΔSMD = -0.31; 95% CI = -0.53, -0.10; P = 0.004). Significant differences were found according to the type of historical control group (based either on growth study or clinical archive; 11 meta-analyses; ΔSMD = 0.40; 95% CI = 0.21, 0.59; P control groups in orthodontic clinical research was associated with deflation of treatment effects, which was independent from whether the interventional group was prospective or retrospective and from the study's sample size. Caution is warranted when interpreting clinical studies with historical untreated control groups or when interpreting systematic reviews that include such studies. PROSPERO (CRD42015024179). None. © The Author 2016. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  15. Social cognition and the cerebellum: a meta-analysis of over 350 fMRI studies.

    Science.gov (United States)

    Van Overwalle, Frank; Baetens, Kris; Mariën, Peter; Vandekerckhove, Marie

    2014-02-01

    This meta-analysis explores the role of the cerebellum in social cognition. Recent meta-analyses of neuroimaging studies since 2008 demonstrate that the cerebellum is only marginally involved in social cognition and emotionality, with a few meta-analyses pointing to an involvement of at most 54% of the individual studies. In this study, novel meta-analyses of over 350 fMRI studies, dividing up the domain of social cognition in homogeneous subdomains, confirmed this low involvement of the cerebellum in conditions that trigger the mirror network (e.g., when familiar movements of body parts are observed) and the mentalizing network (when no moving body parts or unfamiliar movements are present). There is, however, one set of mentalizing conditions that strongly involve the cerebellum in 50-100% of the individual studies. In particular, when the level of abstraction is high, such as when behaviors are described in terms of traits or permanent characteristics, in terms of groups rather than individuals, in terms of the past (episodic autobiographic memory) or the future rather than the present, or in terms of hypothetical events that may happen. An activation likelihood estimation (ALE) meta-analysis conducted in this study reveals that the cerebellum is critically implicated in social cognition and that the areas of the cerebellum which are consistently involved in social cognitive processes show extensive overlap with the areas involved in sensorimotor (during mirror and self-judgments tasks) as well as in executive functioning (across all tasks). We discuss the role of the cerebellum in social cognition in general and in higher abstraction mentalizing in particular. We also point out a number of methodological limitations of some available studies on the social brain that hamper the detection of cerebellar activity.

  16. Individual participant data meta-analysis of prognostic factor studies: state of the art?

    Directory of Open Access Journals (Sweden)

    Abo-Zaid Ghada

    2012-04-01

    Full Text Available Abstract Background Prognostic factors are associated with the risk of a subsequent outcome in people with a given disease or health condition. Meta-analysis using individual participant data (IPD, where the raw data are synthesised from multiple studies, has been championed as the gold-standard for synthesising prognostic factor studies. We assessed the feasibility and conduct of this approach. Methods A systematic review to identify published IPD meta-analyses of prognostic factors studies, followed by detailed assessment of a random sample of 20 articles published from 2006. Six of these 20 articles were from the IMPACT (International Mission for Prognosis and Analysis of Clinical Trials in traumatic brain injury collaboration, for which additional information was also used from simultaneously published companion papers. Results Forty-eight published IPD meta-analyses of prognostic factors were identified up to March 2009. Only three were published before 2000 but thereafter a median of four articles exist per year, with traumatic brain injury the most active research field. Availability of IPD offered many advantages, such as checking modelling assumptions; analysing variables on their continuous scale with the possibility of assessing for non-linear relationships; and obtaining results adjusted for other variables. However, researchers also faced many challenges, such as large cost and time required to obtain and clean IPD; unavailable IPD for some studies; different sets of prognostic factors in each study; and variability in study methods of measurement. The IMPACT initiative is a leading example, and had generally strong design, methodological and statistical standards. Elsewhere, standards are not always as high and improvements in the conduct of IPD meta-analyses of prognostic factor studies are often needed; in particular, continuous variables are often categorised without reason; publication bias and availability bias are rarely

  17. Random and systematic errors in case–control studies calculating the injury risk of driving under the influence of psychoactive substances

    DEFF Research Database (Denmark)

    Houwing, Sjoerd; Hagenzieker, Marjan; Mathijssen, René P.M.;

    2013-01-01

    injury in car crashes. The calculated odds ratios in these studies showed large variations, despite the use of uniform guidelines for the study designs. The main objective of the present article is to provide insight into the presence of random and systematic errors in the six DRUID case-control studies....... The list of indicators that was identified in this study is useful both as guidance for systematic reviews and meta-analyses and for future epidemiological studies in the field of driving under the influence to minimize sources of errors already at the start of the study. © 2013 Published by Elsevier Ltd....

  18. Quality of systematic reviews: an example of studies comparing artificial disc replacement with fusion in the cervical spine.

    Science.gov (United States)

    Tashani, Osama A; El-Tumi, Hanan; Aneiba, Khaled

    2015-01-01

    Cervical artificial disc replacement (C-ADR) is now an alternative to anterior cervical discectomy and fusion (ACDF). Many studies have evaluated the efficacy of C-ADR compared with ACDF. This led to a series of systematic reviews and meta-analyses to evaluate the evidence of the superiority of one intervention against the other. The aim of the study presented here was to evaluate the quality of these reviews and meta-analyses. Medline via Ovid, Embase, and Cochrane Library were searched using the keywords: (total disk replacement, prosthesis, implantation, discectomy, and arthroplasty) AND (cervical vertebrae, cervical spine, and spine) AND (systematic reviews, reviews, and meta-analysis). Screening and data extraction were conducted by two reviewers independently. Two reviewers then assessed the quality of the selected reviews and meta-analysis using 11-item AMSTAR score which is a validated measurement tool to assess the methodological quality of systematic reviews. Screening of full reports of 46 relevant abstracts resulted in the selection of 15 systematic reviews and/or meta-analyses as eligible for this study. The two reviewers' inter-rater agreement level was high as indicated by kappa of >0.72. The AMSTAR score of the reviews ranged from 3 to 11. Only one study (a Cochrane review) scored 100% (AMSTAR 11). Five studies scored below (AMSTAR 5) indicating low-quality reviews. The most significant drawbacks of reviews of a score below 5 were not using an extensive search strategy, failure to use the scientific quality of the included studies appropriately in formulating a conclusion, not assessing publication bias, and not reporting the excluded studies. With a significant exception of a Cochrane review, the methodological quality of systematic reviews evaluating the evidence of C-ADR versus ACDF has to be improved.

  19. Cumulative association between age-related macular degeneration and less studied genetic variants in PLEKHA1/ARMS2/HTRA1: a meta and gene-cluster analysis.

    Science.gov (United States)

    Yu, Weihong; Dong, Shuqian; Zhao, Chuntao; Wang, Haina; Dai, Fei; Yang, Jingyun

    2013-10-01

    The objective of this study is to examine the cumulative effect of the less studied genetic variants in PLEKHA1/ARMS2/HTRA1 on age-related macular degeneration (AMD). We performed an extensive literature search for studies on the association between AMD and the less studied genetic variants in PLEKHA1/ARMS2/HTRA1. Multiple meta-analyses were performed to evaluate the association between individual genetic variants and AMD. A gene-cluster analysis was used to investigate the cumulative effect of these less studied genetic variants on AMD. A total of 23 studies from 20 published papers met the eligibility criteria and were included in our analyses. Several genetic variants in the gene cluster are significantly associated with AMD in our meta-analyses or in individual studies. Gene-cluster analysis reveals a strong cumulative association between these genetic variants in this gene cluster and AMD (p studies in our meta-analyses; and rs3793917, the SNP with the largest sample size, were not significantly associated with AMD (both p's > 0.12). Sensitivity analyses reveal significant association of AMD with rs2736911 in Chinese but not in Caucasian, with c.372_815del443ins54 in Caucasian but not in Chinese, and with rs1049331 in both ethnic groups. These less studied genetic variants have a significant cumulative effect on wet AMD. Our study provides evidence of the joint contribution of genetic variants in PLEKHA1/ARMS2/HTRA1 to AMD risk, in addition to the two widely studied genetic variants whose association with AMD was well established.

  20. Fluoropyrimidine and platinum toxicity pharmacogenetics: an umbrella review of systematic reviews and meta-analyses.

    Science.gov (United States)

    Campbell, Jared M; Bateman, Emma; Peters, Micah Dj; Bowen, Joanne M; Keefe, Dorothy M; Stephenson, Matthew D

    2016-03-01

    Fluoropyrimidine (FU) and platinum-based chemotherapies are greatly complicated by their associated toxicities. This umbrella systematic review synthesized all systematic reviews that investigated associations between germline variations and toxicity, with the aim of informing personalized medicine. Systematic reviews are important in pharmacogenetics where false positives are common. Four systematic reviews were identified for FU-induced toxicity and three for platinum. Polymorphisms of DPYD and TYMS, but not MTHFR, were statistically significantly associated with FU-induced toxicity (although only DPYD had clinical significance). For platinum, GSTP1 was found to not be associated with toxicity. This umbrella systematic review has synthesized the best available evidence on the pharmacogenetics of FU and platinum toxicity. It provides a useful reference for clinicians and identifies important research gaps.

  1. Meta-analyses of Theory use in Medication Adherence Intervention Research

    Science.gov (United States)

    Conn, Vicki S.; Enriquez, Maithe; Ruppar, Todd M.; Chan, Keith C.

    2016-01-01

    Objective This systematic review applied meta-analytic procedures to integrate primary research that examined theory- or model-linked medication adherence interventions. Methods Extensive literature searching strategies were used to locate trials testing interventions with medication adherence behavior outcomes measured by electronic event monitoring, pharmacy refills, pill counts, and self-reports. Random-effects model analysis was used to calculate standardized mean difference effect sizes for medication adherence outcomes. Results Codable data were extracted from 146 comparisons with 19,348 participants. The most common theories and models were social cognitive theory and motivational interviewing. The overall weighted effect size for all interventions comparing treatment and control participants was 0.294. The effect size for interventions based on single-theories was 0.323 and for multiple-theory interventions was 0.214. Effect sizes for individual theories and models ranged from 0.041 to 0.447. The largest effect sizes were for interventions based on the health belief model (0.477) and adult learning theory (0.443). The smallest effect sizes were for interventions based on PRECEDE (0.041) and self-regulation (0.118). Conclusion These findings suggest that theory- and model-linked interventions have a significant but modest effect on medication adherence outcomes. PMID:26931748

  2. Genome-wide meta-analyses identify three loci associated with primary biliary cirrhosis

    Science.gov (United States)

    Liu, Xiangdong; Invernizzi, Pietro; Lu, Yue; Kosoy, Roman; Lu, Yan; Bianchi, Ilaria; Podda, Mauro; Xu, Chun; Xie, Gang; Macciardi, Fabio; Selmi, Carlo; Lupoli, Sara; Shigeta, Russell; Ransom, Michael; Lleo, Ana; Lee, Annette T; Mason, Andrew L; Myers, Robert P; Peltekian, Kevork M; Ghent, Cameron N; Bernuzzi, Francesca; Zuin, Massimo; Rosina, Floriano; Borghesio, Elisabetta; Floreani, Annarosa; Lazzari, Roberta; Niro, Grazia; Andriulli, Angelo; Muratori, Luigi; Muratori, Paolo; Almasio, Piero L; Andreone, Pietro; Margotti, Marzia; Brunetto, Maurizia; Coco, Barbara; Alvaro, Domenico; Bragazzi, Maria C; Marra, Fabio; Pisano, Alessandro; Rigamonti, Cristina; Colombo, Massimo; Marzioni, Marco; Benedetti, Antonio; Fabris, Luca; Strazzabosco, Mario; Portincasa, Piero; Palmieri, Vincenzo O; Tiribelli, Claudio; Croce, Lory; Bruno, Savino; Rossi, Sonia; Vinci, Maria; Prisco, Cleofe; Mattalia, Alberto; Toniutto, Pierluigi; Picciotto, Antonio; Galli, Andrea; Ferrari, Carlo; Colombo, Silvia; Casella, Giovanni; Morini, Lorenzo; Caporaso, Nicola; Colli, Agostino; Spinzi, Giancarlo; Montanari, Renzo; Gregersen, Peter K; Heathcote, E Jenny; Hirschfield, Gideon M; Siminovitch, Katherine A; Amos, Christopher I; Gershwin, M Eric; Seldin, Michael F

    2011-01-01

    A genome-wide association screen for primary biliary cirrhosis risk alleles was performed in an Italian cohort. The results from the Italian cohort replicated IL12A and IL12RB associations, and a combined meta-analysis using a Canadian dataset identified newly associated loci at SPIB (P = 7.9 × 10–11, odds ratio (OR) = 1.46), IRF5-TNPO3 (P = 2.8 × 10–10, OR = 1.63) and 17q12-21 (P = 1.7 × 10–10, OR = 1.38). PMID:20639880

  3. A Systematic Review and Meta-Analyses of Nonsucrose Sweet Solutions for Pain Relief in Neonates

    Directory of Open Access Journals (Sweden)

    Mariana Bueno

    2013-01-01

    Full Text Available BACKGROUND: Sucrose has been demonstrated to provide analgesia for minor painful procedures in infants. However, results of trials investigating other sweet solutions for neonatal pain relief have not yet been synthesized.

  4. Detecting Bias in Meta-Analyses of Distance Education Research: Big Pictures We Can Rely On

    Science.gov (United States)

    Bernard, Robert M.; Borokhovski, Eugene; Tamim, Rana M.

    2014-01-01

    This article has two interrelated purposes. The first is to explain how various forms of bias, if introduced during any stage of a meta-analysis, can provide the consumer with a misimpression of the state of a research literature. Five of the most important bias-producing aspects of a meta-analysis are presented and discussed. Second, armed with…

  5. Significant issues raised by meta-analyses of cancer mortality and dioxin exposure.

    OpenAIRE

    Starr, Thomas B.

    2003-01-01

    Consistent with results from an earlier U.S. Environmental Protection Agency meta-analysis of three occupational cohorts, Crump et al. [Environ Health Perspect 111:681-687 (2003)] recently concluded that "dioxin TEQ [toxic equivalent] exposures within roughly 3-fold of current background levels may be carcinogenic" to humans. In contrast, my meta-analysis using an intercept-only model implied zero additional human cancer deaths from all exposures to dioxin-like compounds, including those aris...

  6. Significant issues raised by meta-analyses of cancer mortality and dioxin exposure.

    Science.gov (United States)

    Starr, Thomas B

    2003-09-01

    Consistent with results from an earlier U.S. Environmental Protection Agency meta-analysis of three occupational cohorts, Crump et al. [Environ Health Perspect 111:681-687 (2003)] recently concluded that "dioxin TEQ [toxic equivalent] exposures within roughly 3-fold of current background levels may be carcinogenic" to humans. In contrast, my meta-analysis using an intercept-only model implied zero additional human cancer deaths from all exposures to dioxin-like compounds, including those arising via dietary intake. How can different investigators reach such markedly different conclusions from similar analyses of essentially the same data? The answer lies in different selections for a dose metric, different assumptions regarding the elimination half-life for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in humans, different assumptions regarding the importance of the most recent 15 years of exposure, and extrapolations from potential effects of TCDD exposure to potential effects of TEQ exposures. Resolution of the ongoing debate regarding the potential human carcinogenicity of dioxin will require detailed information on exposure to TCDD and on direct-acting carcinogens in the workplace, as well as a dose-response model that adequately reflects TCDD's characteristics as a promoter.

  7. Effect of lower sodium intake on health: systematic review and meta-analyses

    OpenAIRE

    Aburto, NJ; Ziolkovska, A; Hooper, L.; Elliott, P.; Cappuccio, FP; Meerpohl, JJ

    2013-01-01

    Objective To assess the effect of decreased sodium intake on blood pressure, related cardiovascular diseases, and potential adverse effects such as changes in blood lipids, catecholamine levels, and renal function. Design Systematic review and meta-analysis. Data sources Cochrane Central Register of Controlled Trials, Medline, Embase, WHO International Clinical Trials Registry Platform, the Latin American and Caribbean health science literature database, and the reference lists of previous re...

  8. Meta-analyses of Big Six Interests and Big Five Personality Factors.

    Science.gov (United States)

    Larson, Lisa M.; Rottinghaus, Patrick J.; Borgen, Fred H.

    2002-01-01

    Meta-analysis of 24 samples demonstrated overlap between Holland's vocational interest domains (measured by Self Directed Search, Strong Interest Inventory, and Vocational Preference Inventory) and Big Five personality factors (measured by Revised NEO Personalty Inventory). The link is stronger for five interest-personality pairs:…

  9. Sex based subgroup differences in randomized controlled trials: empirical evidence from Cochrane meta-analyses.

    Science.gov (United States)

    Wallach, Joshua D; Sullivan, Patrick G; Trepanowski, John F; Steyerberg, Ewout W; Ioannidis, John P A

    2016-11-24

     To evaluate the frequency, validity, and relevance of statistically significant (PUpToDate, an online physician-authored clinical decision support resource, suggested differential management of men and women for one of these sex-treatment interactions.  Statistically significant sex-treatment interactions are only slightly more frequent than what would be expected by chance and there is little evidence of subsequent corroboration or clinical relevance of sex-treatment interactions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  10. Meta-analyses are no substitute for registered replications: a skeptical perspective on religious priming.

    Science.gov (United States)

    van Elk, Michiel; Matzke, Dora; Gronau, Quentin F; Guan, Maime; Vandekerckhove, Joachim; Wagenmakers, Eric-Jan

    2015-01-01

    According to a recent meta-analysis, religious priming has a positive effect on prosocial behavior (Shariff et al., 2015). We first argue that this meta-analysis suffers from a number of methodological shortcomings that limit the conclusions that can be drawn about the potential benefits of religious priming. Next we present a re-analysis of the religious priming data using two different meta-analytic techniques. A Precision-Effect Testing-Precision-Effect-Estimate with Standard Error (PET-PEESE) meta-analysis suggests that the effect of religious priming is driven solely by publication bias. In contrast, an analysis using Bayesian bias correction suggests the presence of a religious priming effect, even after controlling for publication bias. These contradictory statistical results demonstrate that meta-analytic techniques alone may not be sufficiently robust to firmly establish the presence or absence of an effect. We argue that a conclusive resolution of the debate about the effect of religious priming on prosocial behavior - and about theoretically disputed effects more generally - requires a large-scale, preregistered replication project, which we consider to be the sole remedy for the adverse effects of experimenter bias and publication bias.

  11. Meta-analyses are no substitute for registered replications: a skeptical perspective on religious priming

    NARCIS (Netherlands)

    van Elk, M.; Matzke, D.; Gronau, Q.F.; Guan, M.; Vandekerckhove, J.; Wagenmakers, E.-J.

    2015-01-01

    According to a recent meta-analysis, religious priming has a positive effect on prosocial behavior (Shariff et al., 2015). We first argue that this meta-analysis suffers from a number of methodological shortcomings that limit the conclusions that can be drawn about the potential benefits of religiou

  12. Interventions for tic disorders: An overview of systematic reviews and meta analyses.

    Science.gov (United States)

    Yang, Chunsong; Hao, Zilong; Zhu, Cairong; Guo, Qin; Mu, Dezhi; Zhang, Lingli

    2016-04-01

    We conducted a comprehensive search and the overview included 22 systematic reviews (SRs) for treating tic disorders (TDs). Three SRs indicated typical antipsychotics (i.e., haloperidol, pimozide) were efficacious in the reduction of tic severity compared with placebo but with poor tolerability. Six SRs assessed the efficacy of atypical antipsychotics and indicated that atypical antipsychotics (i.e., risperidone, aripiprazole) could significantly improved tic symptoms compared with placebo or typical antipsychotics with less AEs. Four SRs indicated alpha adrenergic agonists (i.e., clonidine, guanfacine) could improve tic symptoms. Two SRs assessed the efficacy of antiepileptic drugs and indicated topiramate was a promising therapy. Six SRs evaluated the efficacy of behavior therapy and showed habit reversal therapy (HRT) and exposure and response prevention (ERP) were effective. One SR evaluated the efficacy deep brain stimulation (DBS) and indicated DBS is a promising treatment option for severe cases of TS. In conclusion, RCTs directly comparing different pharmacological treatment options are scarce. In practice, typical and atypical antipsychotics are often considered firstly while other pharmacological medications are suggested as alternatives in the case of treatment failure or contradictory outcomes. Behavioral therapies can be used either alone or in combination with medication.

  13. A systematic review of meta-analyses on gene polymorphisms and gastric cancer risk

    NARCIS (Netherlands)

    F. Gianfagna (Francesco); E. de Feo (Emma); C.M. van Duijn (Cock); G. Ricciardi (Gualtiero); S. Boccia (Stefania)

    2008-01-01

    textabstractBackground: Individual variations in gastric cancer risk have been associated in the last decade with specific variant alleles of different genes that are present in a significant proportion of the population. Polymorphisms may modify the effects of environmental exposures, and these

  14. Natural killer cells: from CD3(-)NKp46(+) to post-genomics meta-analyses.

    Science.gov (United States)

    Walzer, Thierry; Jaeger, Sébastien; Chaix, Julie; Vivier, Eric

    2007-06-01

    The original definition of NK cells was based on their 'natural' cytolytic response against tumor cells and virus-infected cells in the absence of specific immunization. However, the term 'natural killer' reflects neither the education/maturation requirements before NK cells can kill nor the entirety of their biological functions. In light of new functional assays, genetic models and genomics analysis, we propose a more accurate definition of NK cells. This definition includes the phenotypical identification of NK cells as CD3(-)NKp46(+) cells across mammalian species. In general, this attempt to redefine NK cells also highlights the need to update the operational definition of cell types in the post-genomic area.

  15. Rethinking individualism and collectivism: evaluation of theoretical assumptions and meta-analyses.

    Science.gov (United States)

    Oyserman, Daphna; Coon, Heather M; Kemmelmeier, Markus

    2002-01-01

    Are Americans more individualistic and less collectivistic than members of other groups? The authors summarize plausible psychological implications of individualism-collectivism (IND-COL), meta-analyze cross-national and within-United States IND-COL differences, and review evidence for effects of IND-COL on self-concept, well-being, cognition, and relationality. European Americans were found to be both more individualistic-valuing personal independence more-and less collectivistic-feeling duty to in-groups less-than others. However, European Americans were not more individualistic than African Americans, or Latinos, and not less collectivistic than Japanese or Koreans. Among Asians, only Chinese showed large effects, being both less individualistic and more collectivistic. Moderate IND-COL effects were found on self-concept and relationality, and large effects were found on attribution and cognitive style.

  16. Meta-Analyses from a Collaborative Project in Mobile Lifelong Learning

    Science.gov (United States)

    Arrigo, Marco; Kukulska-Hulme, Agnes; Arnedillo-Sanchez, Inmaculada; Kismihok, Gabor

    2013-01-01

    This paper focuses on the use of mobile technologies in relation to the aims of the European Union's Lifelong Learning programme. First, we explain the background to the notion of mobile lifelong learning. We then present a methodological framework to analyse and identify good practices in mobile lifelong learning, based on the outcomes of the…

  17. ArrayWiki: an enabling technology for sharing public microarray data repositories and meta-analyses.

    Science.gov (United States)

    Stokes, Todd H; Torrance, J T; Li, Henry; Wang, May D

    2008-05-28

    A survey of microarray databases reveals that most of the repository contents and data models are heterogeneous (i.e., data obtained from different chip manufacturers), and that the repositories provide only basic biological keywords linking to PubMed. As a result, it is difficult to find datasets using research context or analysis parameters information beyond a few keywords. For example, to reduce the "curse-of-dimension" problem in microarray analysis, the number of samples is often increased by merging array data from different datasets. Knowing chip data parameters such as pre-processing steps (e.g., normalization, artefact removal, etc), and knowing any previous biological validation of the dataset is essential due to the heterogeneity of the data. However, most of the microarray repositories do not have meta-data information in the first place, and do not have a a mechanism to add or insert this information. Thus, there is a critical need to create "intelligent" microarray repositories that (1) enable update of meta-data with the raw array data, and (2) provide standardized archiving protocols to minimize bias from the raw data sources. To address the problems discussed, we have developed a community maintained system called ArrayWiki that unites disparate meta-data of microarray meta-experiments from multiple primary sources with four key features. First, ArrayWiki provides a user-friendly knowledge management interface in addition to a programmable interface using standards developed by Wikipedia. Second, ArrayWiki includes automated quality control processes (caCORRECT) and novel visualization methods (BioPNG, Gel Plots), which provide extra information about data quality unavailable in other microarray repositories. Third, it provides a user-curation capability through the familiar Wiki interface. Fourth, ArrayWiki provides users with simple text-based searches across all experiment meta-data, and exposes data to search engine crawlers (Semantic Agents) such as Google to further enhance data discovery. Microarray data and meta information in ArrayWiki are distributed and visualized using a novel and compact data storage format, BioPNG. Also, they are open to the research community for curation, modification, and contribution. By making a small investment of time to learn the syntax and structure common to all sites running MediaWiki software, domain scientists and practioners can all contribute to make better use of microarray technologies in research and medical practices. ArrayWiki is available at http://www.bio-miblab.org/arraywiki.

  18. Prepotent response inhibition and interference control in autism spectrum disorders: two meta-analyses

    NARCIS (Netherlands)

    Geurts, H.M.; van den Bergh, S.F.W.M.; Ruzzano, L.

    2014-01-01

    Search String Advanced > Saved Searches > ARTICLE TOOLS Get PDF (432K) Save to My Profile E-mail Link to this Article Export Citation for this Article Get Citation Alerts Request Permissions More Sharing ServicesShare|Share on citeulikeShare on facebookShare on deliciousShare on www.mendeley.comShar

  19. Evaluation of the association between acne and smoking: systematic review and meta-analysis of cross-sectional studies

    Directory of Open Access Journals (Sweden)

    Alice Mannocci

    2010-09-01

    Full Text Available

    Background: Acne vulgaris is one of the most common skin diseases with a multifactorial pathogenesis. Examination of the literature regarding the contribution of smoking to acne shows contradictory results. The aim of this study was to undertake a systematic review of the literature and meta-analysis about the association between acne and smoking.

    Methods: A systematic review and meta-analysis, when possible were performed. The literature review was based on Pubmed, Scopus and Google Scholar searches using the keywords “(smoking OR tobacco OR nicotine OR cigarettes AND acne”. Only cross-sectional studies were included. Meta-analyses were performed using the RevMan software version 5 for Windows. Four different meta-analyses were carried out: one evaluating the association between smoking habit and acne, one including data stratified by gender, one for studies with a quality score > 6, and one relating to acne classification.

    Results: Six studies were selected. The first meta-analysis, including all studies, showed a non significant role of smoke in the development of acne: OR 1.05 (95% CI: 0.66–1.67 with random effect estimate. The second meta-analyses, including data stratified by gender, showed a OR=0.99 (95% CI: 0.57–1.73 for males and a OR of 1.45 (95% CI: 0.08–24.64 for females, using random effect for the heterogeneity in both cases. The third meta-analysis, included studies with a quality score >6 resulted in an estimated OR= 0.69 (95% CI: 0.55–0.85: in this case it was possible to use the fixed effect estimate. The last meta-analysis, concerning the severity grading, showed a non-significant result: OR=1.09 (95% CI: 0.61–1.95 using the random effect approach.

    Conclusions: The first two meta-analyses found no signification association between smoking and

  20. Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers-Part I. general guidance and tips

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi; Park, Seong Ho [Dept. of Radiology, and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); Lee, June Young [Dept. of Biostatistics, Korea University College of Medicine, Seoul (Korea, Republic of)

    2015-12-15

    In the field of diagnostic test accuracy (DTA), the use of systematic review and meta-analyses is steadily increasing. By means of objective evaluation of all available primary studies, these two processes generate an evidence-based systematic summary regarding a specific research topic. The methodology for systematic review and meta-analysis in DTA studies differs from that in therapeutic/interventional studies, and its content is still evolving. Here we review the overall process from a practical standpoint, which may serve as a reference for those who implement these methods.

  1. Levels of red blood cell fatty acids in patients with psychosis, their unaffected siblings, and healthy controls

    NARCIS (Netherlands)

    S. Medema (Suzanne); L.P.C.M. Mocking (Remco); M. Koëter (Maarten); F.M. Vaz (Frédéric M.); C. Meijer (Carin); L. Haan (Lieuwe); N.J.M. De Van Beveren (Nico J. M.); R. Kahn; L. de Haan (Lieuwe); J. Van Os (Jim); D. Wiersma (Durk); R. Bruggeman (Richard); W. Cahn (Wiepke); I. Myin-Germeys (Inez)

    2016-01-01

    textabstractBackground: Two recent meta- Analyses showed decreased red blood cell (RBC) polyunsaturated fatty acids (FA) in schizophrenia and related disorders. However, both these meta- Analyses report considerable heterogeneity, probably related to differences in patient samples between studies. H

  2. Stroke Genetics Network (SiGN) study: design and rationale for a genome-wide association study of ischemic stroke subtypes.

    Science.gov (United States)

    Meschia, James F; Arnett, Donna K; Ay, Hakan; Brown, Robert D; Benavente, Oscar R; Cole, John W; de Bakker, Paul I W; Dichgans, Martin; Doheny, Kimberly F; Fornage, Myriam; Grewal, Raji P; Gwinn, Katrina; Jern, Christina; Conde, Jordi Jimenez; Johnson, Julie A; Jood, Katarina; Laurie, Cathy C; Lee, Jin-Moo; Lindgren, Arne; Markus, Hugh S; McArdle, Patrick F; McClure, Leslie A; Mitchell, Braxton D; Schmidt, Reinhold; Rexrode, Kathryn M; Rich, Stephen S; Rosand, Jonathan; Rothwell, Peter M; Rundek, Tatjana; Sacco, Ralph L; Sharma, Pankaj; Shuldiner, Alan R; Slowik, Agnieszka; Wassertheil-Smoller, Sylvia; Sudlow, Cathie; Thijs, Vincent N S; Woo, Daniel; Worrall, Bradford B; Wu, Ona; Kittner, Steven J

    2013-10-01

    Meta-analyses of extant genome-wide data illustrate the need to focus on subtypes of ischemic stroke for gene discovery. The National Institute of Neurological Disorders and Stroke SiGN (Stroke Genetics Network) contributes substantially to meta-analyses that focus on specific subtypes of stroke. The National Institute of Neurological Disorders and Stroke SiGN includes ischemic stroke cases from 24 genetic research centers: 13 from the United States and 11 from Europe. Investigators harmonize ischemic stroke phenotyping using the Web-based causative classification of stroke system, with data entered by trained and certified adjudicators at participating genetic research centers. Through the Center for Inherited Diseases Research, the Network plans to genotype 10,296 carefully phenotyped stroke cases using genome-wide single nucleotide polymorphism arrays and adds to these another 4253 previously genotyped cases, for a total of 14,549 cases. To maximize power for subtype analyses, the study allocates genotyping resources almost exclusively to cases. Publicly available studies provide most of the control genotypes. Center for Inherited Diseases Research-generated genotypes and corresponding phenotypes will be shared with the scientific community through the US National Center for Biotechnology Information database of Genotypes and Phenotypes, and brain MRI studies will be centrally archived. The Stroke Genetics Network, with its emphasis on careful and standardized phenotyping of ischemic stroke and stroke subtypes, provides an unprecedented opportunity to uncover genetic determinants of ischemic stroke.

  3. Poor replication validity of biomedical association studies reported by newspapers

    Science.gov (United States)

    Smith, Andy; Boraud, Thomas; Gonon, François

    2017-01-01

    Objective To investigate the replication validity of biomedical association studies covered by newspapers. Methods We used a database of 4723 primary studies included in 306 meta-analysis articles. These studies associated a risk factor with a disease in three biomedical domains, psychiatry, neurology and four somatic diseases. They were classified into a lifestyle category (e.g. smoking) and a non-lifestyle category (e.g. genetic risk). Using the database Dow Jones Factiva, we investigated the newspaper coverage of each study. Their replication validity was assessed using a comparison with their corresponding meta-analyses. Results Among the 5029 articles of our database, 156 primary studies (of which 63 were lifestyle studies) and 5 meta-analysis articles were reported in 1561 newspaper articles. The percentage of covered studies and the number of newspaper articles per study strongly increased with the impact factor of the journal that published each scientific study. Newspapers almost equally covered initial (5/39 12.8%) and subsequent (58/600 9.7%) lifestyle studies. In contrast, initial non-lifestyle studies were covered more often (48/366 13.1%) than subsequent ones (45/3718 1.2%). Newspapers never covered initial studies reporting null findings and rarely reported subsequent null observations. Only 48.7% of the 156 studies reported by newspapers were confirmed by the corresponding meta-analyses. Initial non-lifestyle studies were less often confirmed (16/48) than subsequent ones (29/45) and than lifestyle studies (31/63). Psychiatric studies covered by newspapers were less often confirmed (10/38) than the neurological (26/41) or somatic (40/77) ones. This is correlated to an even larger coverage of initial studies in psychiatry. Whereas 234 newspaper articles covered the 35 initial studies that were later disconfirmed, only four press articles covered a subsequent null finding and mentioned the refutation of an initial claim. Conclusion Journalists

  4. Coffee intake and risk of pancreatic cancer: an updated meta-analysis of prospective studies.

    Science.gov (United States)

    Nie, Kechao; Xing, Zhihua; Huang, Wei; Wang, Weihao; Liu, Weiping

    2016-08-01

    Inconsistent results on the relationship between coffee consumption and pancreatic cancer risk has been reported in both epidemiological studies and previous meta-analyses. This updated meta-analysis was conducted to assess the association of coffee intake with pancreatic cancer risk. We evaluated the relationship of coffee ingestion and pancreatic cancer risk by performing a meta-analysis of prospective cohort studies and made an explicit document search in the PubMed database before November 2015. We also obtained prospective cohort studies of previous meta-analyses. A random-effects model was used for pooling overall relative risk. Twenty articles of coffee ingestion and pancreatic cancer were contained in our meta-analysis. The summary relative risk (RR) of pancreatic cancer and coffee intake of the highest compared with lowest category was 0.99 (95% CI=0.81-1.21), with statistically moderate heterogeneity (I2=47.9%, P=0.008). The heterogeneity reduced to I2=38.5% after excluding one study, and the RR was 1.06 (95% CI=0.94-1.20). The relationships of coffee intake and pancreatic risk did not modified by geographic areas, sex of participants, number of cases, follow-up years, and the number of adjusted confounders. Dose-response analysis indicated that every one-cup increase in coffee consumption was associated with an 1% increase in pancreatic cancer risk. No statistically significant publication biases existed. Coffee consumption may weakly increase the risk of pancreatic cancer.

  5. Postoperative Complications of Laparoscopic Total Gastrectomy versus Open Total Gastrectomy for Gastric Cancer in a Meta-Analysis of High-Quality Case-Controlled Studies

    Directory of Open Access Journals (Sweden)

    Mikito Inokuchi

    2016-01-01

    Full Text Available Background. Some meta-analyses of case-controlled studies (CCSs have shown that laparoscopic or laparoscopy-assisted total gastrectomy (LTG had some short-term advantages over open total gastrectomy (OTG. However, postoperative complications differed somewhat among the meta-analyses, and some CCSs included in the meta-analyses had mismatched factors between LTG and OTG. Methods. CCSs comparing postoperative complications between LTG and OTG were identified in PubMed and Embase. Studies matched for patients’ status, tumor stage, and the extents of lymph-node dissection were included. Outcomes of interest, such as anastomotic, other intra-abdominal, wound, and pulmonary complications, were evaluated in a meta-analysis performed using Review Manager version 5.3 software. Result. This meta-analysis included a total of 2,560 patients (LTG, 1,073 patients; OTG, 1,487 patients from 15 CCSs. Wound complications were significantly less frequent in LTG than in OTG (n = 2,430; odds ratio [OR] 0.30, 95% confidence interval [CI] 0.29–0.85, P=0.01, I2 = 0%, and OR 0.46, 95% CI 0.17–0.52, P<0.0001, I2 = 0%. However, the incidence of anastomotic complications was slightly but not significantly higher in LTG than in OTG (n = 2,560; OR 1.44, 95% CI 0.96–2.16, P=0.08, I2 = 0%. Conclusion. LTG was associated with a lower incidence of wound-related postoperative complications than was OTG in this meta-analysis of CCSs; however, some concern remains about anastomotic problems associated with LTG.

  6. The albatross plot: A novel graphical tool for presenting results of diversely reported studies in a systematic review.

    Science.gov (United States)

    Harrison, Sean; Jones, Hayley E; Martin, Richard M; Lewis, Sarah J; Higgins, Julian P T

    2017-09-01

    Meta-analyses combine the results of multiple studies of a common question. Approaches based on effect size estimates from each study are generally regarded as the most informative. However, these methods can only be used if comparable effect sizes can be computed from each study, and this may not be the case due to variation in how the studies were done or limitations in how their results were reported. Other methods, such as vote counting, are then used to summarize the results of these studies, but most of these methods are limited in that they do not provide any indication of the magnitude of effect. We propose a novel plot, the albatross plot, which requires only a 1-sided P value and a total sample size from each study (or equivalently a 2-sided P value, direction of effect and total sample size). The plot allows an approximate examination of underlying effect sizes and the potential to identify sources of heterogeneity across studies. This is achieved by drawing contours showing the range of effect sizes that might lead to each P value for given sample sizes, under simple study designs. We provide examples of albatross plots using data from previous meta-analyses, allowing for comparison of results, and an example from when a meta-analysis was not possible. Copyright © 2017 The Authors. Research Synthesis Methods Published by John Wiley & Sons Ltd.

  7. The use of meta-analysis or research synthesis to combine driving simulation or naturalistic study results on driver distraction.

    Science.gov (United States)

    Caird, Jeff K; Johnston, Katherine A; Willness, Chelsea R; Asbridge, Mark

    2014-06-01

    Three important and inter-related topics are addressed in this paper. First, the importance of meta-analysis and research synthesis methods to combine studies on traffic safety, in general, and on driver distraction, in particular, is briefly reviewed. Second, naturalistic, epidemiologic, and driving simulation studies on driver distraction are used to illustrate convergent and divergent results that have accumulated thus far in this domain of research. In particular, mobile phone conversation, passenger presence, and text messaging naturalistic studies use meta-analyses and research syntheses to illustrate important patterns of results that are in need of more in-depth study. Third, a number of driver distraction study limitations such as poorly defined dependent variables, lack of methodological detail, and omission of statistical information prevent the integration of many studies into meta-analyses. In addition, the overall quality of road safety studies suffers from these same limitations and suggestions for improvement are made to guide researchers and reviewers. Practical Applications. The use of research synthesis and meta-analysis provide comprehensive estimates of the impact of distractions on driving performance, which can be used to guide public policy and future research.

  8. Methods for meta-analysis in genetic association studies: a review of their potential and pitfalls.

    Science.gov (United States)

    Kavvoura, Fotini K; Ioannidis, John P A

    2008-02-01

    Meta-analysis offers the opportunity to combine evidence from retrospectively accumulated or prospectively generated data. Meta-analyses may provide summary estimates and can help in detecting and addressing potential inconsistency between the combined datasets. Application of meta-analysis in genetic associations presents considerable potential and several pitfalls. In this review, we present basic principles of meta-analytic methods, adapted for human genome epidemiology. We describe issues that arise in the retrospective or the prospective collection of relevant data through various sources, common traps to consider in the appraisal of evidence and potential biases that may interfere. We describe the relative merits and caveats for common methods used to trace inconsistency across studies along with possible reasons for non-replication of proposed associations. Different statistical models may be employed to combine data and some common misconceptions may arise in the process. Several meta-analysis diagnostics are often applied or misapplied in the literature, and we comment on their use and limitations. An alternative to overcome limitations arising from retrospective combination of data from published studies is to create networks of research teams working in the same field and perform collaborative meta-analyses of individual participant data, ideally on a prospective basis. We discuss the advantages and the challenges inherent in such collaborative approaches. Meta-analysis can be a useful tool in dissecting the genetics of complex diseases and traits, provided its methods are properly applied and interpreted.

  9. Some limitations on the external validity of psychotherapy efficacy studies and suggestions for future research.

    Science.gov (United States)

    Shean, Glenn D

    2012-01-01

    Increased emphasis on identifying empirically supported treatments (ESTs) has enhanced the scientific basis for psychotherapy practice, but uncritical acceptance of ESTs as the basis for credentialing and policy decisions risks stifling innovation and creativity in the field. There are limitations inherent in efficacy studies of psychotherapy that can constrain external validity. This article discusses several limitations on the external validity of efficacy studies, as well as other issues related to evaluating psychotherapy outcome research. These limitations and concerns include: 1) the practice of maximizing homogeneity by selecting participants diagnosed with a single Axis I disorder; 2) the practice of requiring manualized therapies for efficacy research; 3) the assumption that lasting and meaningful changes occur and can be assessed within a relatively short time frame; 4) the assumption that valid assessments of outcome can be conducted in randomized control trials studies without concern for researcher allegiance; and 5) the view that evidence of effectiveness from non-RCT design studies can be ignored. Finally, alternative research approaches for studying psychotherapy that can potentially supplement knowledge gained from efficacy studies and foster continued innovation and creativity in the field are discussed.

  10. The prefrontal dysfunction in individuals with Internet gaming disorder: a meta-analysis of functional magnetic resonance imaging studies.

    Science.gov (United States)

    Meng, Yajing; Deng, Wei; Wang, Huiyao; Guo, Wanjun; Li, Tao

    2015-07-01

    With the advancement in high-resolution magnetic resonance imaging (MRI) technology and automated analysis, studies on functional MRI (fMRI) made it possible to identify the functional activity of brain in vivo in individuals with Internet gaming disorder (IGD), and to explore the underpinning neuroscience basis of IGD. Yet, no available literature has systemically reviewed the fMRI studies of IGD using meta-analyses. This study reviewed 61 candidate articles and finally selected 10 qualified voxel-wise whole-brain analysis studies for performing a comprehensive series of meta-analyses employing effect size signed differential mapping approach. Compared with healthy controls, subjects with IGD showed a significant activation in the bilateral medial frontal gyrus (MFG) and the left cingulate gyrus, as well as the left medial temporal gyrus and fusiform gyrus. Furthermore, the on-line time of IGD subjects was positively correlated with activations in the left MFG and the right cingulated gyrus. These findings implicate the important role of dysfunctional prefrontal lobe in the neuropathological mechanism of IGD. Considering the overlapped role of prefrontal lobe in the reward and self-regulatory system, our results provided supportive evidence for the reclassification of IGD as a behavioural addiction.

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

    Science.gov (United States)

    Cunningham, Michael R; Baumeister, Roy F

    2016-01-01

    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 et al., 2010). Meta-analyses are supposed to reduce bias in literature reviews. Carter et al.'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 and Precision Effect Estimate with Standard Error (PEESE) procedures. Despite these serious problems, the Carter et al. (2015) meta-analysis results actually indicate that there is a real depletion effect - contrary to their title.

  12. Facilitation of school re-entry and peer acceptance of children with cancer: a review and meta-analysis of intervention studies.

    Science.gov (United States)

    Helms, A S; Schmiegelow, K; Brok, J; Johansen, C; Thorsteinsson, T; Simovska, V; Larsen, H B

    2016-01-01

    Increased survival rates from childhood cancer call for efforts to reintegrate children with cancer back into their academic and social environments. The aims of this study were to: (1) review and analyse the existing literature on school re-entry interventions for children with cancer; and (2) discuss the importance of peer involvement in the treatment. Relevant databases were searched using equivalent search algorithms and six studies were selected that target children with cancer and/or their classmates. Two authors independently reviewed the literature for data extraction. The articles were reviewed using the PRISMA model for reporting reviews. Statistical calculations for the meta-analyses were done using Review Manager 5.2. The meta-analyses showed significant effects of school re-entry programmes in terms of enhancing academic achievement in children with cancer (P = 0.008) and lowering their levels of depression (P = 0.05). Increased knowledge among classmates was associated with less fear and a more positive attitude towards the child with cancer. Due to limited numbers of patients, lack of control groups, and the diversity of intervention strategies used in previous studies, there is a need for intervention programmes exploring the optimal path for the reintegration of children with cancer into the education system and into their peer groups.

  13. Risk Factors for Development of Acute Kidney Injury in Critically Ill Patients: A Systematic Review and Meta-Analysis of Observational Studies

    Directory of Open Access Journals (Sweden)

    Rodrigo Cartin-Ceba

    2012-01-01

    Full Text Available Background. Acute kidney injury (AKI is a frequent complication of critically ill patients. The impact of different risk factors associated with this entity in the ICU setting is unknown. Objectives. The purpose of this research was to assess the risk factors associated with the development of AKI in critically ill patients by meta-analyses of observational studies. Data Extraction. Two reviewers independently and in duplicate used a standardized form to collect data from published reports. Authors were contacted for missing data. The Newcastle-Ottawa scale assessed study quality. Data Synthesis. Data from 31 diverse studies that enrolled 504,535 critically ill individuals from a wide variety of ICUs were included. Separate random-effects meta-analyses demonstrated a significantly increased risk of AKI with older age, diabetes, hypertension, higher baseline creatinine, heart failure, sepsis/systemic inflammatory response syndrome, use of nephrotoxic drugs, higher severity of disease scores, use of vasopressors/inotropes, high risk surgery, emergency surgery, use of intra-aortic balloon pump, and longer time in cardiopulmonary bypass pump. Conclusion. The best available evidence suggests an association of AKI with 13 different risk factors in subjects admitted to the ICU. Predictive models for identification of high risk individuals for developing AKI in all types of ICU are required.

  14. A critical meta-analysis of lens model studies in human judgment and decision-making.

    Science.gov (United States)

    Kaufmann, Esther; Reips, Ulf-Dietrich; Wittmann, Werner W

    2013-01-01

    Achieving accurate judgment ('judgmental achievement') is of utmost importance in daily life across multiple domains. The lens model and the lens model equation provide useful frameworks for modeling components of judgmental achievement and for creating tools to help decision makers (e.g., physicians, teachers) reach better judgments (e.g., a correct diagnosis, an accurate estimation of intelligence). Previous meta-analyses of judgment and decision-making studies have attempted to evaluate overall judgmental achievement and have provided the basis for evaluating the success of bootstrapping (i.e., replacing judges by linear models that guide decision making). However, previous meta-analyses have failed to appropriately correct for a number of study design artifacts (e.g., measurement error, dichotomization), which may have potentially biased estimations (e.g., of the variability between studies) and led to erroneous interpretations (e.g., with regards to moderator variables). In the current study we therefore conduct the first psychometric meta-analysis of judgmental achievement studies that corrects for a number of study design artifacts. We identified 31 lens model studies (N = 1,151, k = 49) that met our inclusion criteria. We evaluated overall judgmental achievement as well as whether judgmental achievement depended on decision domain (e.g., medicine, education) and/or the level of expertise (expert vs. novice). We also evaluated whether using corrected estimates affected conclusions with regards to the success of bootstrapping with psychometrically-corrected models. Further, we introduce a new psychometric trim-and-fill method to estimate the effect sizes of potentially missing studies correct psychometric meta-analyses for effects of publication bias. Comparison of the results of the psychometric meta-analysis with the results of a traditional meta-analysis (which only corrected for sampling error) indicated that artifact correction leads to a) an

  15. Impact of analysing continuous outcomes using final values, change scores and analysis of covariance on the performance of meta-analytic methods: a simulation study.

    Science.gov (United States)

    McKenzie, Joanne E; Herbison, G Peter; Deeks, Jonathan J

    2016-12-01

    When meta-analysing intervention effects calculated from continuous outcomes, meta-analysts often encounter few trials, with potentially a small number of participants, and a variety of trial analytical methods. It is important to know how these factors affect the performance of inverse-variance fixed and DerSimonian and Laird random effects meta-analytical methods. We examined this performance using a simulation study. Meta-analysing estimates of intervention effect from final values, change scores, ANCOVA or a random mix of the three yielded unbiased estimates of pooled intervention effect. The impact of trial analytical method on the meta-analytic performance measures was important when there was no or little heterogeneity, but was of little relevance as heterogeneity increased. On the basis of larger than nominal type I error rates and poor coverage, the inverse-variance fixed effect method should not be used when there are few small trials. When there are few small trials, random effects meta-analysis is preferable to fixed effect meta-analysis. Meta-analytic estimates need to be cautiously interpreted; type I error rates will be larger than nominal, and confidence intervals will be too narrow. Use of trial analytical methods that are more efficient in these circumstances may have the unintended consequence of further exacerbating these issues. © 2015 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd. © 2015 The Authors. Research Synthesis Methods published by John Wiley & Sons, Ltd.

  16. Fe and Cu do not differ in Parkinson's disease: a replication study plus meta-analysis.

    Science.gov (United States)

    Mariani, Stefania; Ventriglia, Mariacarla; Simonelli, Ilaria; Donno, Silvia; Bucossi, Serena; Vernieri, Fabrizio; Melgari, Jean-Marc; Pasqualetti, Patrizio; Rossini, Paolo M; Squitti, Rosanna

    2013-02-01

    To evaluate whether iron and copper levels in serum, plasma, and cerebrospinal fluid are disarranged in Parkinson's disease (PD), we performed meta-analyses of 33 studies on the topic published from 1987 to 2011 and contextually carried out a replication study in serum by ourselves as well. We found no variation in metals between PD patients and healthy controls, according to our replication study. The metaregression for sex revealed that serum copper differences found in some studies could be referred to the different percentage of women in the PD sample. Transferrin and transferrin saturation levels found increased in PD subjects underline the concept to extend the iron study in PD to iron master proteins.

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

    Science.gov (United States)

    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.

  18. Periodontal disease and stroke: a meta-analysis of cohort studies.

    Science.gov (United States)

    Lafon, A; Pereira, B; Dufour, T; Rigouby, V; Giroud, M; Béjot, Y; Tubert-Jeannin, S

    2014-09-01

    This review aimed to determine the association between periodontal disease and stroke incidence by a meta-analysis of cohort studies. Cohort studies that evaluated the incidence of stroke (fatal or non-fatal, ischaemic or haemorrhagic) and baseline periodontal status and calculated relative risk values were included. The quality of the included studies was assessed using an evaluation grid. The analyses were conducted separately for three outcomes: periodontitis, gingivitis and loss of teeth. Adjusted values of relative risk or of hazard ratio were used to assess risk values in each study. Random effects meta-analyses were conducted when data could be pooled. From the 743 references retrieved, only nine cohort studies were suitable for inclusion in this review. Quality scores of the studies varied greatly. Three prospective studies, which used reliable indicators of periodontal disease, obtained the highest scores. Conversely, three studies that used a subjective evaluation of stroke incidence or diagnosed stroke without imaging obtained the lowest score. The results of the meta-analyses varied depending on the outcome considered and the type of stroke. The risk of stroke was significantly increased by the presence of periodontitis [relative risk 1.63 (1.25, 2.00)]. Tooth loss was also a risk factor for stroke [relative risk 1.39 (1.13, 1.65)]. The risk of stroke did not vary significantly with the presence of gingivitis. This review shows that periodontitis and tooth loss are associated with the occurrence of stroke. © 2014 The Author(s) European Journal of Neurology © 2014 EAN.

  19. Neuroimaging studies in patients with obsessive-compulsive disorder in China

    Institute of Scientific and Technical Information of China (English)

    Qing FAN; Zeping XIAO

    2013-01-01

    Obsessive-compulsive disorder (OCD) is a common mental disorder of uncertain etiology.Neuroimaging studies of patients with OCD in China started to appear in the late 1990s,identifying structural abnormalities in the gray matter and white matter of the prefrontal lobe,the corpus striatum,and the thalamus.Studies using positron emission tomography (PET),functional magnetic resonance imaging (fMRI),and magnetic resonance spectroscopy (MRS) have found increased metabolism and activation in these brain regions that are correlated with the duration,severity and cognitive symptoms of OCD.After surgery for OCD the activation in these target areas decreases.These results in China are similar to those presented in previous neuroimaging studies,including several meta-analyses from other countries.

  20. Iodine and Mental Development of Children 5 Years Old and Under: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Grace S. Marquis

    2013-04-01

    Full Text Available Several reviews and meta-analyses have examined the effects of iodine on mental development. None focused on young children, so they were incomplete in summarizing the effects on this important age group. The current systematic review therefore examined the relationship between iodine and mental development of children 5 years old and under. A systematic review of articles using Medline (1980–November 2011 was carried out. We organized studies according to four designs: (1 randomized controlled trial with iodine supplementation of mothers; (2 non-randomized trial with iodine supplementation of mothers and/or infants; (3 prospective cohort study stratified by pregnant women’s iodine status; (4 prospective cohort study stratified by newborn iodine status. Average effect sizes for these four designs were 0.68 (2 RCT studies, 0.46 (8 non-RCT studies, 0.52 (9 cohort stratified by mothers’ iodine status, and 0.54 (4 cohort stratified by infants’ iodine status. This translates into 6.9 to 10.2 IQ points lower in iodine deficient children compared with iodine replete children. Thus, regardless of study design, iodine deficiency had a substantial impact on mental development. Methodological concerns included weak study designs, the omission of important confounders, small sample sizes, the lack of cluster analyses, and the lack of separate analyses of verbal and non-verbal subtests. Quantifying more precisely the contribution of iodine deficiency to delayed mental development in young children requires more well-designed randomized controlled trials, including ones on the role of iodized salt.

  1. Vaccinations and childhood type 1 diabetes mellitus: a meta-analysis of observational studies.

    Science.gov (United States)

    Morgan, Eileen; Halliday, Sophia R; Campbell, Gemma R; Cardwell, Chris R; Patte