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

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Voutilainen, Ari; Saaranen, Terhi; Sormunen, Marjorita

2017-03-01

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

Post-Traumatic Stress Disorder, Depression and Anxiety among North Korean Refugees: A Meta-Analysis.

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Taylor, Benjamin Eric; Chekaluk, Eugene; Bennett, Joanne

2017-09-01

Post-traumatic stress disorder is common among North Korean refugees who have fled their country for economic, financial and humanitarian reasons. Co-morbid depression and anxiety are also common among North Korean refugees, due to the difficulties they have faced within their country and during their escape journey. Depression and anxiety complicate treatment for post-traumatic stress disorder, and lead to poorer outcomes. Thus, the aim of the present study was to provide a meta-analysis of studies investigating post-traumatic stress disorder, depression, and anxiety among North Korean refugees. Selected articles were published in English, and included measures of post-traumatic stress, and/or depression and anxiety. 10 studies were included in the depression meta-analysis, and 6 in the anxiety meta-analysis. A random-effects model revealed strong, significant associations between post-traumatic stress and depression, r=0.63, 95% CI (0.51, 0.72), pstress, depression and anxiety were higher among adults and those with more than five years outside of North Korea. Depression appears to be an important treatment focus for North Korean refugees with post-traumatic stress.

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

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

2015-01-01

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

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

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

2016-07-01

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

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

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

2013-01-01

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

Methodology Series Module 6: Systematic Reviews and Meta-analysis.

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Setia, Maninder Singh

2016-01-01

Systematic reviews and meta-analysis have become an important of biomedical literature, and they provide the "highest level of evidence" for various clinical questions. There are a lot of studies - sometimes with contradictory conclusions - on a particular topic in literature. Hence, as a clinician, which results will you believe? What will you tell your patient? Which drug is better? A systematic review or a meta-analysis may help us answer these questions. In addition, it may also help us understand the quality of the articles in literature or the type of studies that have been conducted and published (example, randomized trials or observational studies). The first step it to identify a research question for systematic review or meta-analysis. The next step is to identify the articles that will be included in the study. This will be done by searching various databases; it is important that the researcher should search for articles in more than one database. It will also be useful to form a group of researchers and statisticians that have expertise in conducting systematic reviews and meta-analysis before initiating them. We strongly encourage the readers to register their proposed review/meta-analysis with PROSPERO. Finally, these studies should be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis checklist.

Cognitive-Based Interventions to Improve Mobility: A Systematic Review and Meta-analysis.

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Marusic, Uros; Verghese, Joe; Mahoney, Jeannette R

2018-06-01

A strong relation between cognition and mobility has been identified in aging, supporting a role for enhancement mobility through cognitive-based interventions. However, a critical evaluation of the consistency of treatment effects of cognitive-based interventions is currently lacking. The objective of this study was 2-fold: (1) to review the existing literature on cognitive-based interventions aimed at improving mobility in older adults and (2) to assess the clinical effectiveness of cognitive interventions on gait performance. A systematic review of randomized controlled trials (RCT) of cognitive training interventions for improving simple (normal walking) and complex (dual task walking) gait was conducted in February 2018. Older adults without major cognitive, psychiatric, neurologic, and/or sensory impairments were included. Random effect meta-analyses and a subsequent meta-regression were performed to generate overall cognitive intervention effects on single- and dual-task walking conditions. Ten RCTs met inclusion criteria, with a total of 351 participants included in this meta-analysis. Cognitive training interventions revealed a small effect of intervention on complex gait [effect size (ES) = 0.47, 95% confidence interval (CI) 0.13 to 0.81, P = .007, I 2  = 15.85%], but not simple gait (ES = 0.35, 95% CI -0.01 to 0.71, P = .057, I 2  = 57.32%). Moreover, a meta-regression analysis revealed that intervention duration, training frequency, total number of sessions, and total minutes spent in intervention were not significant predictors of improvement in dual-task walking speed, though there was a suggestive trend toward a negative association between dual-task walking speed improvements and individual training session duration (P = .067). This meta-analysis provides support for the fact that cognitive training interventions can improve mobility-related outcomes, especially during challenging walking conditions requiring higher-order executive

Creativity and Academic Achievement: A Meta-Analysis

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Gajda, Aleksandra; Karwowski, Maciej; Beghetto, Ronald A.

2017-01-01

This article reports on a meta-analysis of 120 studies (total N = 52,578; 782 effects) examining the relationship between creativity and academic achievement in research conducted since the 1960s. Average correlation between creativity and academic achievement was r = 0.22, 95% CI [0.19, 0.24]. An analysis of moderators revealed that this…

Fatal flaws in a recent meta-analysis on abortion and mental health.

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Steinberg, Julia R; Trussell, James; Hall, Kelli S; Guthrie, Kate

2012-11-01

Similar to other reviews within the last 4 years, a thorough review by the Royal College of Psychiatrists, published in December 2011, found that compared to delivery of an unintended pregnancy, abortion does not increase women's risk of mental health problems. In contrast, a meta-analysis published in September 2011 concluded that abortion increases women's risk of mental health problems by 81% and that 10% of mental health problems are attributable to abortions. Like others, we strongly question the quality of this meta-analysis and its conclusions. Here we detail seven errors of this meta-analysis and three significant shortcomings of the included studies because policy, practice and the public have been misinformed. These errors and shortcomings render the meta-analysis' conclusions invalid. Copyright © 2012 Elsevier Inc. All rights reserved.

Meta-analysis reveals an association between signal transducer and activator of transcription-4 polymorphism and hepatocellular carcinoma risk.

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Zhang, Li; Xu, Kuihua; Liu, Chuanmiao; Chen, Jiasheng

2017-03-01

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related mortality worldwide. Signal transducer and activator of transcription (STAT) proteins play a multitude of important functions in liver pathophysiology. Recent studies have indicated associations of rs7574865 single nucleotide polymorphism (SNP) in the STAT4 gene with various autoimmune diseases. The association between STAT4 polymorphism and the risk of HCC has been analyzed in several studies, but results remain inconsistent. This study used a meta-analysis approach to comprehensively investigate the correlation between STAT4 polymorphism and HCC risk based on previously published reports. Studies were searched from the databases of PubMed, EMBase, Web of Science, and the Chinese National Knowledge Infrastructure up to 31 December 2015. The meta-analysis was carried out based on the statement of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Eight published studies, consisting of 7503 HCC patients (cases) and 13 831 individuals without HCC (controls), were included in the present study. Meta-analysis of the included studies revealed that STAT4 rs7574865 polymorphism contributed to the risk of HCC under all four genetic models, consisting of the allelic model (G vs. T: odds ratio [OR], 1.25; 95% confidence interval [CI], 1.19-1.30), the dominant effect model (GG + GT vs. TT: OR, 1.52; 95% CI, 1.26-1.84), the recessive effect model (GG vs. GT + TT: OR, 1.35; 95% CI, 1.21-1.50), and the co-dominant effect model (GG vs.. TT: OR, 1.72; 95% CI, 1.42-2.10) comparisons. No publication bias was indicated from either visualization of the funnel plot or Egger's test. A significantly increased risk of HCC associated with the rs7574865 G was found. The rs7574865 polymorphism might be used as one risk factor for HCC. © 2016 The Japan Society of Hepatology.

Meta-Analyst: software for meta-analysis of binary, continuous and diagnostic data

Directory of Open Access Journals (Sweden)

Schmid Christopher H

2009-12-01

Full Text Available Abstract Background Meta-analysis is increasingly used as a key source of evidence synthesis to inform clinical practice. The theory and statistical foundations of meta-analysis continually evolve, providing solutions to many new and challenging problems. In practice, most meta-analyses are performed in general statistical packages or dedicated meta-analysis programs. Results Herein, we introduce Meta-Analyst, a novel, powerful, intuitive, and free meta-analysis program for the meta-analysis of a variety of problems. Meta-Analyst is implemented in C# atop of the Microsoft .NET framework, and features a graphical user interface. The software performs several meta-analysis and meta-regression models for binary and continuous outcomes, as well as analyses for diagnostic and prognostic test studies in the frequentist and Bayesian frameworks. Moreover, Meta-Analyst includes a flexible tool to edit and customize generated meta-analysis graphs (e.g., forest plots and provides output in many formats (images, Adobe PDF, Microsoft Word-ready RTF. The software architecture employed allows for rapid changes to be made to either the Graphical User Interface (GUI or to the analytic modules. We verified the numerical precision of Meta-Analyst by comparing its output with that from standard meta-analysis routines in Stata over a large database of 11,803 meta-analyses of binary outcome data, and 6,881 meta-analyses of continuous outcome data from the Cochrane Library of Systematic Reviews. Results from analyses of diagnostic and prognostic test studies have been verified in a limited number of meta-analyses versus MetaDisc and MetaTest. Bayesian statistical analyses use the OpenBUGS calculation engine (and are thus as accurate as the standalone OpenBUGS software. Conclusion We have developed and validated a new program for conducting meta-analyses that combines the advantages of existing software for this task.

Serum vitamin D levels in relation to schizophrenia: a systematic review and meta-analysis of observational studies.

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Valipour, Ghazaleh; Saneei, Parvane; Esmaillzadeh, Ahmad

2014-10-01

Although several observational studies have investigated the association between vitamin D status and schizophrenia, we are aware of no comprehensive meta-analysis in this regard. We aimed to conduct a systematic review and a meta-analysis of observational studies to summarize the available data on the association between serum vitamin D levels and schizophrenia. A systematic research on all published articles until October 2013 was conducted in PubMed, ISI (Web of science), SCOPUS, and Google Scholar. All observational studies that had measured serum vitamin D levels in schizophrenic patients were included in the systematic review. After considering exclusion criteria, we had 19 studies for the systematic review that were included in three separate meta-analyses: 1) a meta-analysis on mean levels of 25-hydroxyvitamin D [25(OH)D] (n = 13); 2) a meta-analysis on the prevalence of vitamin D deficiency (n = 8); 3) a meta-analysis on odds ratios (n = 8). Findings from a meta-analysis on means revealed that the overall mean difference in serum 25(OH)D levels between schizophrenic patients and control participants was -5.91 ng/mL [95% confidence interval (CI) -10.68, -1.14]. Subgroup analyses based on study design, the patient's hospitalization status, study quality, and study location did not explain between-study heterogeneity; however, type of biomarker assessed [25-hydroxyvitamin D3 vs 25-hydroxyvitamin D (D2 & D3)] could account for some degree of heterogeneity. RESULTS from the meta-analysis on the prevalence of vitamin D deficiency indicated that the overall prevalence of vitamin D deficiency in schizophrenic patients was 65.3% (95% CI 46.4%-84.2%). Findings from the meta-analysis on odds ratios indicated that vitamin D-deficient persons were 2.16 times (95% CI 1.32, 3.56) more likely to have schizophrenia than those with vitamin D sufficiency. No evidence of heterogeneity was detected. We found a strong association between vitamin D deficiency and schizophrenia

Moral development and recidivism: a meta-analysis

NARCIS (Netherlands)

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

2011-01-01

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

Revealing the association between cerebrovascular accidents and ambient temperature: a meta-analysis

Science.gov (United States)

Zorrilla-Vaca, Andrés; Healy, Ryan Jacob; Silva-Medina, Melissa M.

2017-05-01

The association between cerebrovascular accidents (CVA) and weather has been described across several studies showing multiple conflicting results. In this paper, we aim to conduct a meta-analysis to further clarify this association, as well as to find the potential sources of heterogeneity. PubMed, EMBASE, and Google Scholar were searched from inception through 2015, for articles analyzing the correlation between the incidence of CVA and temperature. A pooled effect size (ES) was estimated using random effects model and expressed as absolute values. Subgroup analyses by type of CVA were also performed. Heterogeneity and influence of covariates—including geographic latitude of the study site, male percentage, average temperature, and time interval—were assessed by meta-regression analysis. Twenty-six articles underwent full data extraction and scoring. A total of 19,736 subjects with CVA from 12 different countries were included and grouped as ischemic strokes (IS; n = 14,199), intracerebral hemorrhages (ICH; n = 3798), and subarachnoid hemorrhages (SAH; n = 1739). Lower ambient temperature was significantly associated with increase in incidence of overall CVA when using unadjusted (pooled ES = 0.23, P < 0.001) and adjusted data (pooled ES = 0.03, P = 0.003). Subgroup analyses showed that lower temperature has higher impact on the incidence of ICH (pooled ES = 0.34, P < 0.001), than that of IS (pooled ES = 0.22, P < 0.001) and SAH (pooled ES = 0.11, P = 0.012). In meta-regression analysis, the geographic latitude of the study site was the most influencing factor on this association ( Z-score = 8.68). Synthesis of the existing data provides evidence supporting that a lower ambient temperature increases the incidence of CVA. Further population-based studies conducted at negative latitudes are needed to clarify the influence of this factor.

Longitudinal Meta-analysis

NARCIS (Netherlands)

Hox, J.J.; Maas, C.J.M.; Lensvelt-Mulders, G.J.L.M.

2004-01-01

The goal of meta-analysis is to integrate the research results of a number of studies on a specific topic. Characteristic for meta-analysis is that in general only the summary statistics of the studies are used and not the original data. When the published research results to be integrated

Meta-Analysis of Associations Between Interleukin-10 Polymorphisms and Susceptibility to Vasculitis.

Science.gov (United States)

Jung, Jae Hyun; Song, Gwan Gyu; Lee, Young Ho

2015-01-01

This study determined whether interleukin-10 (IL-10) polymorphisms are associated with susceptibility to vasculitis. A meta-analysis was conducted of the associations between the IL-10 -1082 G/A, -819 C/T, and -592 C/A polymorphisms and the haplotype of the IL-10-1082 G/A, -819 C/T, -592 C/A polymorphisms and vasculitis. A total of 21 comparative studies involving 4121 patients and 5504 controls were considered in the meta-analysis. Meta-analysis revealed no association between the IL-10-1082 G allele and vasculitis in all study subjects (OR = 0.927, 95% CI = 0.780-1.102, p = 0.389). However, disease-specific meta-analysis showed an association between Wegener's granulomatosis (WG) and the IL-10-1082 G allele (OR = 0.729, 95% CI = 0.547-0.971, p = 0.031). Meta-analysis revealed an association between vasculitis and the IL-10-819 C allele (OR = 0.804, 95% CI = 0.706-0.916, p = 0.001) in all study subjects and Behcet's disease (BD) (OR = 0.724, 95% CI = 0.679-0.781, p vasculitis in all study subjects (OR = 0.805, 95% CI = 0.619-0.938, p = 0.005) and BD (OR = 0.718, 95% CI = 0.661-0.781, p vasculitis in Europeans (OR = 1.239, 95% CI = 1.105-1.513, p = 0.035). This meta-analysis showed that IL-10 polymorphisms are associated with vasculitis susceptibility, especially in WG and BD.

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

Science.gov (United States)

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

2017-12-16

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

Trial Sequential Analysis in systematic reviews with meta-analysis

Directory of Open Access Journals (Sweden)

Jørn Wetterslev

2017-03-01

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

A meta-analysis of fear appeals: implications for effective public health campaigns.

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Witte, K; Allen, M

2000-10-01

The fear appeal literature is examined in a comprehensive synthesis using meta-analytical techniques. The meta-analysis suggests that strong fear appeals produce high levels of perceived severity and susceptibility, and are more persuasive than low or weak fear appeals. The results also indicate that fear appeals motivate adaptive danger control actions such as message acceptance and maladaptive fear control actions such as defensive avoidance or reactance. It appears that strong fear appeals and high-efficacy messages produce the greatest behavior change, whereas strong fear appeals with low-efficacy messages produce the greatest levels of defensive responses. Future directions and practical implications are provided.

Global Prevalence of Elder Abuse: A Meta-analysis and Meta-regression.

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Ho, C Sh; Wong, S Y; Chiu, M M; Ho, R Cm

2017-06-01

Elder abuse is increasingly recognised as a global public health and social problem. There has been limited inter-study comparison of the prevalence and risk factors for elder abuse. This study aimed to estimate the pooled and subtype prevalence of elder abuse worldwide and identify significant associated risk factors. We conducted a meta-analysis and meta-regression of 34 population-based and 17 non-population-based studies. The pooled prevalences of elder abuse were 10.0% (95% confidence interval, 5.2%-18.6%) and 34.3% (95% confidence interval, 22.9%-47.8%) in population-based studies and third party- or caregiver-reported studies, respectively. Being in a marital relationship was found to be a significant moderator using random-effects model. This meta-analysis revealed that third parties or caregivers were more likely to report abuse than older abused adults. Subgroup analyses showed that females and those resident in non-western countries were more likely to be abused. Emotional abuse was the most prevalent elder abuse subtype and financial abuse was less commonly reported by third parties or caregivers. Heterogeneity in the prevalence was due to the high proportion of married older adults in the sample. Subgroup analysis showed that cultural factors, subtypes of abuse, and gender also contributed to heterogeneity in the pooled prevalence of elder abuse.

Tutoring Adolescents in Literacy: A Meta-Analysis

Science.gov (United States)

Jun, Seung Won; Ramirez, Gloria; Cumming, Alister

2010-01-01

What does research reveal about tutoring adolescents in literacy? We conducted a meta-analysis, identifying 152 published studies, of which 12 met rigorous inclusion criteria. We analyzed the 12 studies for the effects of tutoring according to the type, focus, and amount of tutoring; the number, age, and language background of students; and the…

Conducting Meta-Analysis Using SAS

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Arthur, Winfried; Huffcutt, Allen I; Arthur, Winfred

2001-01-01

Conducting Meta-Analysis Using SAS reviews the meta-analysis statistical procedure and shows the reader how to conduct one using SAS. It presents and illustrates the use of the PROC MEANS procedure in SAS to perform the data computations called for by the two most commonly used meta-analytic procedures, the Hunter & Schmidt and Glassian approaches. This book serves as both an operational guide and user's manual by describing and explaining the meta-analysis procedures and then presenting the appropriate SAS program code for computing the pertinent statistics. The practical, step-by-step instru

Meta-analysis of expression and function of neprilysin in Alzheimer's disease.

Science.gov (United States)

Zhang, Huifeng; Liu, Dan; Wang, Yixing; Huang, Huanhuan; Zhao, Yujia; Zhou, Hui

2017-09-14

Neprilysin (NEP) is one of the most important Aβ-degrading enzymes, and its expression and activity in Alzheimer's brain have been widely reported, but the results remain debatable. Thus, the meta-analysis was performed to elucidate the role of NEP in Alzheimer's disease (AD). The relevant case-control or cohort studies were retrieved according to our inclusion/exclusion criteria. Six studies with 123 controls and 141 AD cases, seven studies with 102 controls and 90 AD cases, and four studies with 93 controls and 132 AD cases were included in meta-analysis of NEP's protein, mRNA, and enzyme activity respectively. We conducted Meta regression to detect the sources of heterogeneity and further performed cumulative meta-analysis or subgroup analysis. Our meta-analysis revealed a significantly lower level of NEP mRNA (SMD=-0.44, 95%CI: -0.87, -0.00, p=0.049) in AD cases than in non-AD cases, and such pattern was not altered over time in the cumulative meta-analysis. However, the decrease of NEP protein (SMD=-0.18, 95%CI: -0.62, 0.25) and enzyme activity (SMD=-0.35, 95%CI: -1.03, 0.32) in AD cases did not pass the significance check, while the cumulative meta-analysis by average age showed the pooled effect became insignificant as adding the studies with younger subjects, which indicates that the protein expression and enzyme activity of NEP in the cortex are affected by age. Therefore, the present meta-analysis suggests the need of further investigation of roles of NEP in AD pathogenesis and treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Systematic review and meta-analysis of glyphosate exposure and risk of lymphohematopoietic cancers.

Science.gov (United States)

Chang, Ellen T; Delzell, Elizabeth

2016-01-01

This systematic review and meta-analysis rigorously examines the relationship between glyphosate exposure and risk of lymphohematopoietic cancer (LHC) including NHL, Hodgkin lymphoma (HL), multiple myeloma (MM), and leukemia. Meta-relative risks (meta-RRs) were positive and marginally statistically significant for the association between any versus no use of glyphosate and risk of NHL (meta-RR = 1.3, 95% confidence interval (CI) = 1.0-1.6, based on six studies) and MM (meta-RR = 1.4, 95% CI = 1.0-1.9; four studies). Associations were statistically null for HL (meta-RR = 1.1, 95% CI = 0.7-1.6; two studies), leukemia (meta-RR = 1.0, 95% CI = 0.6-1.5; three studies), and NHL subtypes except B-cell lymphoma (two studies each). Bias and confounding may account for observed associations. Meta-analysis is constrained by few studies and a crude exposure metric, while the overall body of literature is methodologically limited and findings are not strong or consistent. Thus, a causal relationship has not been established between glyphosate exposure and risk of any type of LHC.

Efficacy of anthropometric measures for identifying cardiovascular disease risk in adolescents: review and meta-analysis.

Science.gov (United States)

Lichtenauer, Michael; Wheatley, Sean D; Martyn-St James, Marrissa; Duncan, Michael J; Cobayashi, Fernanda; Berg, Gabriela; Musso, Carla; Graffigna, Mabel; Soutelo, Jimena; Bovet, Pascal; Kollias, Anastasios; Stergiou, George S; Grammatikos, Evangelos; Griffiths, Claire; Ingle, Lee; Jung, Christian

2018-04-12

To compare the ability of body mass index (BMI), waist circumference (WC) and waist to height ratio (WHtR) to estimate cardiovascular disease (CVD) risk levels in adolescents. A systematic review and meta-analysis was performed after a database search for relevant literature (Cochrane, Centre for Review and Dissemination, PubMed, British Nursing Index, CINAHL, BIOSIS citation index, ChildData, metaRegister). 117 records representing 96 studies with 994,595 participants were included in the systematic review, 14 of which (13 studies, n=14,610) were eligible for the meta-analysis. The results of the meta-analysis showed that BMI was a strong indicator of systolic blood pressure, diastolic blood pressure, triglycerides, high-density lipoprotein cholesterol and insulin; but not total cholesterol, low-density lipoprotein or glucose. Few studies were eligible for inclusion in the meta-analysis considering WC or WHtR (n≤2). The narrative synthesis found measures of central adiposity to be consistently valid indicators of the same risk factors as BMI. BMI was an indicator of CVD risk. WC and WHtR were efficacious for indicating the same risk factors BMI performed strongly for, though there was insufficient evidence to judge the relative strength of each measure possibly due to heterogeneity in the methods for measuring and classifying WC.

Causal Meta-Analysis : Methodology and Applications

NARCIS (Netherlands)

Bax, L.J.

2009-01-01

Meta-analysis is a statistical method to summarize research data from multiple studies in a quantitative manner. This dissertation addresses a number of methodological topics in causal meta-analysis and reports the development and validation of meta-analysis software. In the first (methodological)

Meta-analysis a structural equation modeling approach

CERN Document Server

Cheung, Mike W-L

2015-01-01

Presents a novel approach to conducting meta-analysis using structural equation modeling. Structural equation modeling (SEM) and meta-analysis are two powerful statistical methods in the educational, social, behavioral, and medical sciences. They are often treated as two unrelated topics in the literature. This book presents a unified framework on analyzing meta-analytic data within the SEM framework, and illustrates how to conduct meta-analysis using the metaSEM package in the R statistical environment. Meta-Analysis: A Structural Equation Modeling Approach begins by introducing the impo

MetaMeta: integrating metagenome analysis tools to improve taxonomic profiling.

Science.gov (United States)

Piro, Vitor C; Matschkowski, Marcel; Renard, Bernhard Y

2017-08-14

Many metagenome analysis tools are presently available to classify sequences and profile environmental samples. In particular, taxonomic profiling and binning methods are commonly used for such tasks. Tools available among these two categories make use of several techniques, e.g., read mapping, k-mer alignment, and composition analysis. Variations on the construction of the corresponding reference sequence databases are also common. In addition, different tools provide good results in different datasets and configurations. All this variation creates a complicated scenario to researchers to decide which methods to use. Installation, configuration and execution can also be difficult especially when dealing with multiple datasets and tools. We propose MetaMeta: a pipeline to execute and integrate results from metagenome analysis tools. MetaMeta provides an easy workflow to run multiple tools with multiple samples, producing a single enhanced output profile for each sample. MetaMeta includes a database generation, pre-processing, execution, and integration steps, allowing easy execution and parallelization. The integration relies on the co-occurrence of organisms from different methods as the main feature to improve community profiling while accounting for differences in their databases. In a controlled case with simulated and real data, we show that the integrated profiles of MetaMeta overcome the best single profile. Using the same input data, it provides more sensitive and reliable results with the presence of each organism being supported by several methods. MetaMeta uses Snakemake and has six pre-configured tools, all available at BioConda channel for easy installation (conda install -c bioconda metameta). The MetaMeta pipeline is open-source and can be downloaded at: https://gitlab.com/rki_bioinformatics .

Comment on 'Large-Scale Cognitive GWAS Meta-Analysis Reveals Tissue-Specific Neural Expression and Potential Nootropic Drug Targets' by Lam et al.

Science.gov (United States)

Hill, W David

2018-04-01

Intelligence and educational attainment are strongly genetically correlated. This relationship can be exploited by Multi-Trait Analysis of GWAS (MTAG) to add power to Genome-wide Association Studies (GWAS) of intelligence. MTAG allows the user to meta-analyze GWASs of different phenotypes, based on their genetic correlations, to identify association's specific to the trait of choice. An MTAG analysis using GWAS data sets on intelligence and education was conducted by Lam et al. (2017). Lam et al. (2017) reported 70 loci that they described as 'trait specific' to intelligence. This article examines whether the analysis conducted by Lam et al. (2017) has resulted in genetic information about a phenotype that is more similar to education than intelligence.

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

Science.gov (United States)

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

2014-10-01

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

Association between Hypertension and Epistaxis: Systematic Review and Meta-analysis.

Science.gov (United States)

Min, Hyun Jin; Kang, Hyun; Choi, Geun Joo; Kim, Kyung Soo

2017-12-01

Objective Whether there is an association or a cause-and-effect relationship between epistaxis and hypertension is a subject of longstanding controversy. The objective of this systematic review and meta-analysis was to determine the association between epistaxis and hypertension and to verify whether hypertension is an independent risk factor of epistaxis. Data Sources A comprehensive search was performed using the MEDLINE, EMBASE, and Cochrane Library databases. Review Methods The review was performed according to the Meta-analysis of Observational Studies in Epidemiology guidelines and reported using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. Results We screened 2768 unique studies and selected 10 for this meta-analysis. Overall, the risk of epistaxis was significantly increased for patients with hypertension (odds ratio, 1.532 [95% confidence interval (CI), 1.181-1.986]; number needed to treat, 14.9 [95% CI, 12.3-19.0]). Results of the Q test and I 2 statistics suggested considerable heterogeneity ([Formula: see text] = 0.038, I 2 = 49.3%). The sensitivity analysis was performed by excluding 1 study at a time, and it revealed no change in statistical significance. Conclusion Although this meta-analysis had some limitations, our study demonstrated that hypertension was significantly associated with the risk of epistaxis. However, since this association does not support a causal relationship between hypertension and epistaxis, further clinical trials with large patient populations will be required to determine the impact of hypertension on epistaxis.

Meta-analysis reveals host-dependent nitrogen recycling as a mechanism of symbiont control in Aiptasia

KAUST Repository

Cui, Guoxin; Liew, Yi Jin; Li, Yong; Kharbatia, Najeh M.; Zahran, Noura Ibrahim Omar; Emwas, Abdul-Hamid M.; Eguí luz, Ví ctor M; Aranda, Manuel

2018-01-01

in the emerging model organism Aiptasia. However, previous studies identified thousands of putatively symbiosis-related genes, making it difficult to disentangle symbiosis-induced responses from undesired experimental parameters. Using a meta-analysis approach, we

OHBM 2017: Practical intensity based meta-analysis

OpenAIRE

Maumet, Camille

2017-01-01

"Practical intensity-based meta-analysis" slides from my talk in the OHBM 2017 educational talk on Neuroimaging meta-analysis.http://www.humanbrainmapping.org/files/2017/ED Courses/Neuroimaging Meta-Analysis.pdf

Meta-analysis reveals host-dependent nitrogen recycling as a mechanism of symbiont control in Aiptasia

KAUST Repository

Cui, Guoxin

2018-02-22

The metabolic symbiosis with photosynthetic algae of the genus Symbiodinium allows corals to thrive in the oligotrophic environments of tropical seas. Many aspects of this relationship have been investigated using transcriptomic analyses in the emerging model organism Aiptasia. However, previous studies identified thousands of putatively symbiosis-related genes, making it difficult to disentangle symbiosis-induced responses from undesired experimental parameters. Using a meta-analysis approach, we identified a core set of 731 high-confidence symbiosis-associated genes that reveal host-dependent recycling of waste ammonium and amino acid synthesis as central processes in this relationship. Combining transcriptomic and metabolomic analyses, we show that symbiont-derived carbon enables host recycling of ammonium into nonessential amino acids. We propose that this provides a regulatory mechanism to control symbiont growth through a carbon-dependent negative feedback of nitrogen availability to the symbiont. The dependence of this mechanism on symbiont-derived carbon highlights the susceptibility of this symbiosis to changes in carbon translocation, as imposed by environmental stress.

MetaEasy: A Meta-Analysis Add-In for Microsoft Excel

Directory of Open Access Journals (Sweden)

Evangelos Kontopantelis

2009-04-01

Full Text Available Meta-analysis is a statistical methodology that combines or integrates the results ofseveral independent clinical trials considered by the analyst to be `combinable' (Huque1988. However, completeness and user-friendliness are uncommon both in specialisedmeta-analysis software packages and in mainstream statistical packages that have to relyon user-written commands. We implemented the meta-analysis methodology in an Mi-crosoft Excel add-in which is freely available and incorporates more meta-analysis models(including the iterative maximum likelihood and prole likelihood than are usually avail-able, while paying particular attention to the user-friendliness of the package.

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

Science.gov (United States)

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

2017-12-01

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

Trial Sequential Analysis in systematic reviews with meta-analysis

DEFF Research Database (Denmark)

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

2017-01-01

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

Clinimetrics of ultrasound pathologies in osteoarthritis: systematic literature review and meta-analysis.

Science.gov (United States)

Oo, W M; Linklater, J M; Daniel, M; Saarakkala, S; Samuels, J; Conaghan, P G; Keen, H I; Deveza, L A; Hunter, D J

2018-05-01

The aims of this study were to systematically review clinimetrics of commonly assessed ultrasound pathologies in knee, hip and hand osteoarthritis (OA), and to conduct a meta-analysis for each clinimetric. Medline, Embase, and Cochrane Library databases were searched from their inceptions to September 2016. According to the Outcome Measures in Rheumatology (OMERACT) Instrument Selection Algorithm, data extraction focused on ultrasound technical features and performance metrics. Methodological quality was assessed with modified 19-item Downs and Black score and 11-item Quality Appraisal of Diagnostic Reliability (QAREL) score. Separate meta-analyses were performed for clinimetrics: (1) inter-rater/intra-rater reliability; (2) construct validity; (3) criteria validity; and (4) internal/external responsiveness. Statistical Package for the Social Sciences (SPSS), Excel and Comprehensive Meta-analysis were used. Our search identified 1126 records; of these, 100 were eligible, including a total of 8542 patients and 32,373 joints. The average Downs and Black score was 13.01, and average QAREL was 5.93. The stratified meta-analysis was performed only for knee OA, which demonstrated moderate to substantial reliability [minimum kappa > 0.44(0.15,0.74), minimum intraclass correlation coefficient (ICC) > 0.82(0.73-0.89)], weak construct validity against pain (r = 0.12 to 0.27), function (r = 0.15 to 0.23), and blood biomarkers (r = 0.01 to 0.21), but weak to strong correlation with plain radiography (r = 0.13 to 0.60), strong association with Magnetic Resonance Imaging (MRI) [minimum r = 0.60(0.52,0.67)] and strong discrimination against symptomatic patients (OR = 3.08 to 7.46). There was strong criterion validity against cartilage histology [r = 0.66(-0.05,0.93)], and small to moderate internal [standardized mean difference(SMD) = 0.20 to 0.58] and external (r = 0.35 to 0.43) responsiveness to interventions. Ultrasound demonstrated strong criterion

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

Science.gov (United States)

Stetter, Friedhelm; Kupper, Sirko

2002-03-01

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

Does chocolate reduce blood pressure? A meta-analysis

Directory of Open Access Journals (Sweden)

Ried Karin

2010-06-01

Full Text Available Abstract Background Dark chocolate and flavanol-rich cocoa products have attracted interest as an alternative treatment option for hypertension, a known risk factor for cardiovascular disease. Previous meta-analyses concluded that cocoa-rich foods may reduce blood pressure. Recently, several additional trials have been conducted with conflicting results. Our study summarises current evidence on the effect of flavanol-rich cocoa products on blood pressure in hypertensive and normotensive individuals. Methods We searched Medline, Cochrane and international trial registries between 1955 and 2009 for randomised controlled trials investigating the effect of cocoa as food or drink compared with placebo on systolic and diastolic blood pressure (SBP/DBP for a minimum duration of 2 weeks. We conducted random effects meta-analysis of all studies fitting the inclusion criteria, as well as subgroup analysis by baseline blood pressure (hypertensive/normotensive. Meta-regression analysis explored the association between type of treatment, dosage, duration or baseline blood pressure and blood pressure outcome. Statistical significance was set at P Results Fifteen trial arms of 13 assessed studies met the inclusion criteria. Pooled meta-analysis of all trials revealed a significant blood pressure-reducing effect of cocoa-chocolate compared with control (mean BP change ± SE: SBP: -3.2 ± 1.9 mmHg, P = 0.001; DBP: -2.0 ± 1.3 mmHg, P = 0.003. However, subgroup meta-analysis was significant only for the hypertensive or prehypertensive subgroups (SBP: -5.0 ± 3.0 mmHg; P = 0.0009; DBP: -2.7 ± 2.2 mm Hg, P = 0.01, while BP was not significantly reduced in the normotensive subgroups (SBP: -1.6 ± 2.3 mmHg, P = 0.17; DBP: -1.3 ± 1.6 mmHg, P = 0.12. Nine trials used chocolate containing 50% to 70% cocoa compared with white chocolate or other cocoa-free controls, while six trials compared high- with low-flavanol cocoa products. Daily flavanol dosages ranged from 30

Online open neuroimaging mass meta-analysis

DEFF Research Database (Denmark)

Nielsen, Finn Årup; Kempton, Matthew J.; Williams, Steven C. R.

We describe a system for meta-analysis where a wiki stores numerical data in a simple format and a web service performs the numerical computation. We initially apply the system on multiple meta-analyses of structural neuroimaging data results. The described system allows for mass meta-analysis, e...

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

Science.gov (United States)

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

2006-07-12

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

A Meta-Analysis of the Predictors of Delinquency among Girls.

Science.gov (United States)

Hubbard, Dana Jones; Pratt, Travis C.

2002-01-01

Presents the results of a meta-analysis of the predictors of female delinquency. Finds that most of the strong predictors of female delinquency are the same as those for males, including history of antisocial behavior, antisocial attitudes, antisocial peers, and antisocial personality. School and family relationships and a history of…

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

Science.gov (United States)

Imburgio, Michael J; Orr, Joseph M

2018-05-01

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

An overview of meta-analysis for clinicians

Science.gov (United States)

Lee, Young Ho

2018-01-01

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

An overview of meta-analysis for clinicians.

Science.gov (United States)

Lee, Young Ho

2018-03-01

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

Meta-analysis of Neuroblastomas Reveals a Skewed ALK Mutation Spectrum in Tumors with MYCN Amplification

NARCIS (Netherlands)

de Brouwer, Sara; de Preter, Katleen; Kumps, Candy; Zabrocki, Piotr; Porcu, Michaël; Westerhout, Ellen M.; Lakeman, Arjan; Vandesompele, Jo; Hoebeeck, Jasmien; van Maerken, Tom; de Paepe, Anne; Laureys, Geneviève; Schulte, Johannes H.; Schramm, Alexander; van den Broecke, Caroline; Vermeulen, Joëlle; van Roy, Nadine; Beiske, Klaus; Renard, Marleen; Noguera, Rosa; Delattre, Olivier; Janoueix-Lerosey, Isabelle; Kogner, Per; Martinsson, Tommy; Nakagawara, Akira; Ohira, Miki; Caron, Huib N.; Eggert, Angelika; Cools, Jan; Versteeg, Rogier; Speleman, Frank

2010-01-01

Purpose: Activating mutations of the anaplastic lymphoma kinase (ALK) were recently described in neuroblastoma. We carried out a meta-analysis of 709 neuroblastoma tumors to determine their frequency and mutation spectrum in relation to genomic and clinical parameters, and studied the prognostic

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

Directory of Open Access Journals (Sweden)

s Safari

2014-12-01

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

A meta-analysis on gender differences in negotiation outcomes and their moderators.

Science.gov (United States)

Mazei, Jens; Hüffmeier, Joachim; Freund, Philipp Alexander; Stuhlmacher, Alice F; Bilke, Lena; Hertel, Guido

2015-01-01

This meta-analysis investigates gender differences in economic negotiation outcomes. As suggested by role congruity theory, we assume that the behaviors that increase economic negotiation outcomes are more congruent with the male as compared with the female gender role, thereby presenting challenges for women's negotiation performance and reducing their outcomes. Importantly, this main effect is predicted to be moderated by person-based, situation-based, and task-based influences that make effective negotiation behavior more congruent with the female gender role, which should in turn reduce or even reverse gender differences in negotiation outcomes. Using a multilevel modeling approach, this meta-analysis includes 123 effect sizes (overall N = 10,888, including undergraduate and graduate students as well as businesspeople). Studies were included when they enabled the calculation of an effect size reflecting gender differences in achieved economic negotiation outcomes. As predicted, men achieved better economic outcomes than women on average, but gender differences strongly depended on the context: Moderator analysis revealed that gender differences favoring men were reduced when negotiators had negotiation experience, when they received information about the bargaining range, and when they negotiated on behalf of another individual. Moreover, gender differences were reversed under conditions of the lowest predicted role incongruity for women. In conclusion, gender differences in negotiations are contextually bound and can be subject to change. Future research is needed that investigates the underlying mechanisms of new moderators revealed in the current research (e.g., experience). Implications for theoretical explanations of gender differences in negotiation outcomes, for gender inequalities in the workplace, and for future research are discussed. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Network meta-analysis: an introduction for pharmacists.

Science.gov (United States)

Xu, Yina; Amiche, Mohamed Amine; Tadrous, Mina

2018-05-21

Network meta-analysis is a new tool used to summarize and compare studies for multiple interventions, irrespective of whether these interventions have been directly evaluated against each other. Network meta-analysis is quickly becoming the standard in conducting therapeutic reviews and clinical guideline development. However, little guidance is available to help pharmacists review network meta-analysis studies in their practice. Major institutions such as the Cochrane Collaboration, Agency for Healthcare Research and Quality, Canadian Agency for Drugs and Technologies in Health, and National Institute for Health and Care Excellence Decision Support Unit have endorsed utilizing network meta-analysis to establish therapeutic evidence and inform decision making. Our objective is to introduce this novel technique to pharmacy practitioners, and highlight key assumptions behind network meta-analysis studies.

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

Science.gov (United States)

Liao, Xi-Ming; Chen, Ping-Yan

2011-04-01

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

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

Science.gov (United States)

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

2013-01-01

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

International Entrepreneurship: A Meta-Analysis on the Internationalization and Performance Relationship

NARCIS (Netherlands)

Schwens, Christian; Zapkau, F.B.; Bierwerth, Michael; Isidor, Rodrigo; Knight, Gary; Kabst, Rüdiger

2018-01-01

The article conducts a meta-analysis on the relationship between internationalization and firm performance in international entrepreneurship. Empirical evidence from 15,648 internationalizing entrepreneurial firms nested in 43 independent samples reveals a positive relationship between degree and

Meta-Analysis at Middle Age: A Personal History

Science.gov (United States)

Glass, Gene V.

2015-01-01

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

Task versus relationship conflict, team performance and team member satisfaction: a meta-analysis

NARCIS (Netherlands)

de Dreu, C.K.W.; Weingart, L.R.

2003-01-01

This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, resultsrevealed strong and negative correlations between relationship conflict, team performance, and

Statistical Power in Meta-Analysis

Science.gov (United States)

Liu, Jin

2015-01-01

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

Using beta coefficients to impute missing correlations in meta-analysis research: Reasons for caution.

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Roth, Philip L; Le, Huy; Oh, In-Sue; Van Iddekinge, Chad H; Bobko, Philip

2018-06-01

Meta-analysis has become a well-accepted method for synthesizing empirical research about a given phenomenon. Many meta-analyses focus on synthesizing correlations across primary studies, but some primary studies do not report correlations. Peterson and Brown (2005) suggested that researchers could use standardized regression weights (i.e., beta coefficients) to impute missing correlations. Indeed, their beta estimation procedures (BEPs) have been used in meta-analyses in a wide variety of fields. In this study, the authors evaluated the accuracy of BEPs in meta-analysis. We first examined how use of BEPs might affect results from a published meta-analysis. We then developed a series of Monte Carlo simulations that systematically compared the use of existing correlations (that were not missing) to data sets that incorporated BEPs (that impute missing correlations from corresponding beta coefficients). These simulations estimated ρ̄ (mean population correlation) and SDρ (true standard deviation) across a variety of meta-analytic conditions. Results from both the existing meta-analysis and the Monte Carlo simulations revealed that BEPs were associated with potentially large biases when estimating ρ̄ and even larger biases when estimating SDρ. Using only existing correlations often substantially outperformed use of BEPs and virtually never performed worse than BEPs. Overall, the authors urge a return to the standard practice of using only existing correlations in meta-analysis. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Is in-group bias culture-dependent? A meta-analysis across 18 societies.

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Fischer, Ronald; Derham, Crysta

2016-01-01

We report a meta-analysis on the relationship between in-group bias and culture. Our focus is on whether broad macro-contextual variables influence the extent to which individuals favour their in-group. Data from 21,266 participants from 18 societies included in experimental and survey studies were available. Using Hofstede's (1980) and Schwartz (2006) culture-level predictors in a 3-level mixed-effects meta-analysis, we found strong support for the uncertainty-reduction hypothesis. An interaction between Autonomy and real vs artificial groups suggested that in low autonomy contexts, individuals show greater in-group bias for real groups. Implications for social identity theory and intergroup conflict are outlined.

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

Science.gov (United States)

Haimerl, P; Heuwieser, W; Arlt, S

2013-05-01

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

Genetic Polymorphism of Angiotensin-Converting Enzyme and Chronic Obstructive Pulmonary Disease Risk: An Updated Meta-Analysis

Directory of Open Access Journals (Sweden)

Sang Wook Kang

2016-01-01

Full Text Available The relationship between polymorphism of the angiotensin I converting enzyme (ACE gene and chronic obstructive pulmonary disease (COPD has been examined in many previous studies. However, their results were controversial. Therefore, we performed a meta-analysis to evaluate the relationship between the ACE gene and the risk of COPD. Fourteen case-control studies were included in this meta-analysis. The pooled p value, odds ratio (OR, and 95% confidence interval (95% CI were used to investigate the strength of the association. The meta-analysis was performed using comprehensive meta-analysis software. Our meta-analysis results revealed that ACE polymorphisms were not related to the risk of COPD (p>0.05 in each model. In further analyses based on ethnicity, we observed an association between insertion/deletion polymorphism of the ACE gene and risk of COPD in the Asian population (codominant 2, OR = 3.126, 95% CI = 1.919–5.093, p0.05 in each model. In conclusion, the present meta-analysis indicated that the insertion/deletion polymorphism of the ACE gene may be associated with susceptibility to COPD in the Asian population but not in the Caucasian population. However, the results of the present meta-analysis need to be confirmed in a larger sample.

Evolutionary Meta-Analysis of Association Studies Reveals Ancient Constraints Affecting Disease Marker Discovery

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Dudley, Joel T.; Chen, Rong; Sanderford, Maxwell; Butte, Atul J.; Kumar, Sudhir

2012-01-01

Genome-wide disease association studies contrast genetic variation between disease cohorts and healthy populations to discover single nucleotide polymorphisms (SNPs) and other genetic markers revealing underlying genetic architectures of human diseases. Despite scores of efforts over the past decade, many reproducible genetic variants that explain substantial proportions of the heritable risk of common human diseases remain undiscovered. We have conducted a multispecies genomic analysis of 5,831 putative human risk variants for more than 230 disease phenotypes reported in 2,021 studies. We find that the current approaches show a propensity for discovering disease-associated SNPs (dSNPs) at conserved genomic positions because the effect size (odds ratio) and allelic P value of genetic association of an SNP relates strongly to the evolutionary conservation of their genomic position. We propose a new measure for ranking SNPs that integrates evolutionary conservation scores and the P value (E-rank). Using published data from a large case-control study, we demonstrate that E-rank method prioritizes SNPs with a greater likelihood of bona fide and reproducible genetic disease associations, many of which may explain greater proportions of genetic variance. Therefore, long-term evolutionary histories of genomic positions offer key practical utility in reassessing data from existing disease association studies, and in the design and analysis of future studies aimed at revealing the genetic basis of common human diseases. PMID:22389448

Global meta-analysis reveals low consistency of biodiversity congruence relationships.

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Westgate, Martin J; Barton, Philip S; Lane, Peter W; Lindenmayer, David B

2014-05-21

Knowledge of the number and distribution of species is fundamental to biodiversity conservation efforts, but this information is lacking for the majority of species on earth. Consequently, subsets of taxa are often used as proxies for biodiversity; but this assumes that different taxa display congruent distribution patterns. Here we use a global meta-analysis to show that studies of cross-taxon congruence rarely give consistent results. Instead, species richness congruence is highest at extreme spatial scales and close to the equator, while congruence in species composition is highest at large extents and grain sizes. Studies display highest variance in cross-taxon congruence when conducted in areas with dissimilar areal extents (for species richness) or latitudes (for species composition). These results undermine the assumption that a subset of taxa can be representative of biodiversity. Therefore, researchers whose goal is to prioritize locations or actions for conservation should use data from a range of taxa.

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

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

2014-08-01

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

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

Science.gov (United States)

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

2016-09-20

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

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

Science.gov (United States)

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

2016-01-19

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

MTLRP genetic polymorphism (214C>A) was associated with Type 2 diabetes in Caucasian population: a meta-analysis

OpenAIRE

Chen, Li-Li; Han, Song-Mei; Tang, Fei-Fei; Li, Qiang

2014-01-01

Background Previous studies reported the relation between MTLRP genetic polymorphism and type 2 diabetes, however, the conclusion were conflicting. In the present study, we performed a meta-analysis to reveal this association. Methods Literature retrieval, selection and assessment, data extraction, and meta-analyses were performed according to the RevMan 5.0 guidelines. In the meta-analysis, we utilized random-effect model or fixed-effect model to pool the Odds ratio (OR) according to the tes...

Associations between interleukin-10 polymorphisms and susceptibility to juvenile idiopathic arthritis: a systematic review and meta-analysis.

Science.gov (United States)

Harsini, Sara; Saghazadeh, Amene; Nedjat, Saharnaz; Rezaei, Nima

2018-03-01

Cytokine genes, including interleukin-10 (IL-10), are known to play important roles in the pathogenesis of juvenile idiopathic arthritis (JIA). This study aims to determine whether the IL-10 polymorphisms confer susceptibility to JIA. A meta-analysis was performed on the associations between the IL-10 -1082 G/A, -592 C/A, and -819 C/T polymorphisms and JIA. A total number of 7 studies involving 1,785 patients and 6,142 controls were considered in the meta-analysis. Meta-analysis of the IL-10 -592 C/A and -819 C/T polymorphisms showed no association with JIA in the study participants, or in Caucasian or Middle Eastern participants. Meta-analysis of the IL-10 -1082 A allele in all study participants, Caucasian and Middle Eastern, showed significant associations with RA (overall ORs were 1.17, 1.15, and 1.41, respectively). Meta-analysis of the AA versus GG genotype of the IL-10 -1082 G/A polymorphism revealed significant associations with JIA (OR = 3.66, 95% CI = 1.44-9.29, P = 0.006) in participants from Middle Eastern countries. Additionally, meta-analysis of the GG versus AA+GA genotypes of the IL-10 -1082 G/A polymorphism revealed the GG genotype as the protective factor against JIA in the Middle Eastern subgroup (OR = 0.44, 95% CI = 0.20-0.94, P = 0,04). Moreover, meta-analysis of the IL-10 -1082 A allele in 4 studies on Hardy-Weinberg equilibrium showed a significant association with JIA (OR = 1.17, 95% CI = 1.07-1.28, P = 0.0009). No association was found between the IL-10 (-1082, -819, -592) ACC, ATA, and GCC haplotypes and JIA. These results suggest that the IL-10 -1082 G/A polymorphism confers susceptibility to JIA.

Human papillomavirus and gastrointestinal cancer in Iranian population: A systematic review and meta-analysis.

Science.gov (United States)

Omrani-Navai, Versa; Alizadeh-Navaei, Reza; Yahyapour, Yousef; Hedayatizadeh-Omran, Akbar; Abediankenari, Saeid; Janbabaei, Ghasem; Toghani, Fatima

2017-01-01

Gastrointestinal (GI) malignancies are the most common cancers and account for nearly half of all cancer-related deaths in Iran. There was a strong association between human papillomavirus (HPV) infection and urogenital cancers, in particular the cervix. However, there is no clear causal relationship in all types of cancers, including gastrointestinal cancers. Therefore, the present study as a systematic review and meta-analysis was designed to evaluate the prevalence and relation of HPV in GI cancers. This systematic review and meta-analysis study assess the prevalence of human papillomavirus in GI cancers in Iran. Data were collected by searching electronic databases, including PubMed, Google Scholar, Scopus, SID and Iranmedex by English and Persian key words up to August 2016. Key words included: Human Papillomavirus, HPV, Cancer, Neoplasm, Carcinoma, Esophageal, colorectal, Gastrointestinal and Iran articles were entered in the EndNote software and duplicate papers were excluded. Data were extracted and analyzed by comprehensive meta-analysis software, Version 2 (CMA.V2) and random effects model. Finally, we included 17 studies in this meta-analysis. The prevalence of HPV in Iranian patients with GI cancers was 16.4% (CI95%: 10.4-24.9). Considering all HPV types, the odds ratio of GI cancers in positive patients was 3.03 (CI95%: 1.42-6.45) while in patients with HPV-16 was 3.62 (CI: 1.43-4.82). The results show a strong relationship between HPV infection especially high-risk HPV type 16 and GI cancers in Iranian population.

Integromics network meta-analysis on cardiac aging offers robust multi-layer modular signatures and reveals micronome synergism.

Science.gov (United States)

Dimitrakopoulou, Konstantina; Vrahatis, Aristidis G; Bezerianos, Anastasios

2015-03-04

The avalanche of integromics and panomics approaches shifted the deciphering of aging mechanisms from single molecular entities to communities of them. In this orientation, we explore the cardiac aging mechanisms - risk factor for multiple cardiovascular diseases - by capturing the micronome synergism and detecting longevity signatures in the form of communities (modules). For this, we developed a meta-analysis scheme that integrates transcriptome expression data from multiple cardiac-specific independent studies in mouse and human along with proteome and micronome interaction data in the form of multiple independent weighted networks. Modularization of each weighted network produced modules, which in turn were further analyzed so as to define consensus modules across datasets that change substantially during lifespan. Also, we established a metric that determines - from the modular perspective - the synergism of microRNA-microRNA interactions as defined by significantly functionally associated targets. The meta-analysis provided 40 consensus integromics modules across mouse datasets and revealed microRNA relations with substantial collective action during aging. Three modules were reproducible, based on homology, when mapped against human-derived modules. The respective homologs mainly represent NADH dehydrogenases, ATP synthases, cytochrome oxidases, Ras GTPases and ribosomal proteins. Among various observations, we corroborate to the involvement of miR-34a (included in consensus modules) as proposed recently; yet we report that has no synergistic effect. Moving forward, we determined its age-related neighborhood in which HCN3, a known heart pacemaker channel, was included. Also, miR-125a-5p/-351, miR-200c/-429, miR-106b/-17, miR-363/-92b, miR-181b/-181d, miR-19a/-19b, let-7d/-7f, miR-18a/-18b, miR-128/-27b and miR-106a/-291a-3p pairs exhibited significant synergy and their association to aging and/or cardiovascular diseases is supported in many cases by a

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

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

2016-01-01

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

Rethinking Meta-Analysis: Applications for Air Pollution Data and Beyond

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Goodman, Julie E; Petito Boyce, Catherine; Sax, Sonja N; Beyer, Leslie A; Prueitt, Robyn L

2015-01-01

Meta-analyses offer a rigorous and transparent systematic framework for synthesizing data that can be used for a wide range of research areas, study designs, and data types. Both the outcome of meta-analyses and the meta-analysis process itself can yield useful insights for answering scientific questions and making policy decisions. Development of the National Ambient Air Quality Standards illustrates many potential applications of meta-analysis. These applications demonstrate the strengths and limitations of meta-analysis, issues that arise in various data realms, how meta-analysis design choices can influence interpretation of results, and how meta-analysis can be used to address bias and heterogeneity. Reviewing available data from a meta-analysis perspective can provide a useful framework and impetus for identifying and refining strategies for future research. Moreover, increased pervasiveness of a meta-analysis mindset—focusing on how the pieces of the research puzzle fit together—would benefit scientific research and data syntheses regardless of whether or not a quantitative meta-analysis is undertaken. While an individual meta-analysis can only synthesize studies addressing the same research question, the results of separate meta-analyses can be combined to address a question encompassing multiple data types. This observation applies to any scientific or policy area where information from a variety of disciplines must be considered to address a broader research question. PMID:25969128

Monocyte chemoattractant protein-1 promoter -2518 polymorphism and susceptibility to vasculitis, rheumatoid arthritis, and multiple sclerosis: A meta-analysis.

Science.gov (United States)

Lee, Y H; Bae, S-C

2016-03-20

The purpose of this study was to examine whether the monocyte chemoattractant protein-1 (MCP-1) promoter -2518 A/G polymorphism (rs1024611) is associated with susceptibility to vasculitis, rheumatoid arthritis (RA), or multiple sclerosis (MS). A meta-analysis was conducted on the association between the MCP-1 -2518 A/G polymorphism and vasculitis, RA, and MS. Fourteen studies from 13 articles, including six on vasculitis, five on RA, and three on MS, consisting of 3,038 patients and 3,545 controls were available for the meta-analysis. The meta-analysis revealed no association between the MCP-1 -2518 G allele and vasculitis (odds ratio [OR] = 0.990, 95% confidence interval [CI] = 0.749-1.309, p = 0.943). Stratification by ethnicity indicated no association between the G allele of the MCP-1 -2518 A/G polymorphism and vasculitis in Asians and Caucasians. Meta-analysis by vasculitis type revealed an association between the GG+GA genotype of the MCP-1 -2518 A/G polymorphism and Behçet's disease (BD; OR = 1.349, 95% CI = 1.013-1.796, p = 0.040). However, sensitivity analysis showed that the association was not statistically significant after removing a study that was conducted in China (OR = 1.030, 95% CI = 0.667-1.590, p = 0.895), which indicated that the association was not statistically robust. The meta-analysis revealed no association between the MCP-1 -2518 G allele and RA (OR = 0.986, 95% CI = 0.890-1.093, p = 0.793) or MS (OR = 1.281, 95% CI = 0.802-2.046, p = 0.301). Our meta-analysis demonstrates that the MCP-1 -2518 A/G polymorphism is not associated with susceptibility to vasculitis, RA, or MS.

Bayesian Meta-Analysis of Coefficient Alpha

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Brannick, Michael T.; Zhang, Nanhua

2013-01-01

The current paper describes and illustrates a Bayesian approach to the meta-analysis of coefficient alpha. Alpha is the most commonly used estimate of the reliability or consistency (freedom from measurement error) for educational and psychological measures. The conventional approach to meta-analysis uses inverse variance weights to combine…

Genome-wide meta-analysis in alopecia areata resolves HLA associations and reveals two new susceptibility loci

NARCIS (Netherlands)

Betz, Regina C; Petukhova, Lynn; Ripke, Stephan; Huang, Hailiang; Menelaou, Androniki; Redler, Silke; Becker, Tim; Heilmann, Stefanie; Yamany, Tarek; Duvic, Madeliene; Hordinsky, Maria; Norris, David; Price, Vera H; Mackay-Wiggan, Julian; de Jong, Annemieke; DeStefano, Gina M; Moebus, Susanne; Böhm, Markus; Blume-Peytavi, Ulrike; Wolff, Hans; Lutz, Gerhard; Kruse, Roland; Bian, Li; Amos, Christopher I; Lee, Annette; Gregersen, Peter K; Blaumeiser, Bettina; Altshuler, David; Clynes, Raphael; de Bakker, Paul I W; Nöthen, Markus M; Daly, Mark J; Christiano, Angela M

2015-01-01

Alopecia areata (AA) is a prevalent autoimmune disease with 10 known susceptibility loci. Here we perform the first meta-analysis of research on AA by combining data from two genome-wide association studies (GWAS), and replication with supplemented ImmunoChip data for a total of 3,253 cases and

GWAMA: software for genome-wide association meta-analysis

Directory of Open Access Journals (Sweden)

Mägi Reedik

2010-05-01

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

Gender Differences in Self-Reported Posttraumatic Growth: A Meta-Analysis

Science.gov (United States)

Vishnevsky, Tanya; Cann, Arnie; Calhoun, Lawrence G.; Tedeschi, Richard G.; Demakis, George J.

2010-01-01

A meta-analysis was conducted to examine the direction and magnitude of gender differences in self-reported posttraumatic growth. Results from 70 studies (N = 16,076) revealed a small to moderate gender difference (g = 0.27, 95% CI = 0.21 -0.32), with women reporting more posttraumatic growth than men. Moderator analyses were then conducted to…

Trial Sequential Methods for Meta-Analysis

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Kulinskaya, Elena; Wood, John

2014-01-01

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

Association between TYK2 polymorphisms and susceptibility to autoimmune rheumatic diseases: a meta-analysis.

Science.gov (United States)

Lee, Y H; Bae, S-C

2016-10-01

This study aimed to explore whether TYK2 polymorphisms are associated with susceptibility to autoimmune rheumatic diseases. We conducted a meta-analysis on the association between TYK2 polymorphisms and autoimmune rheumatic diseases. Twelve studies with a total of 16,335 patients and 30,065 controls were included in the meta-analysis. Meta-analysis revealed an association between rheumatic diseases and the 2 allele of the TYK2 rs2304256 (OR = 0.885, 95% CI = 0.802-0.978, p = 0.016). Furthermore, stratification by ethnicity identified a significant association between this polymorphism and rheumatic diseases in Caucasians (OR = 0.822, 95% CI = 0.706-0.889, p = 9.5 × 10(-7)), but not in Asians (OR = 1.127, 95% CI = 0.835-1.522, p = 0.434). Meta-analysis by rheumatic disease type revealed a significant association between the 2 allele of the TYK2 rs2304256 and SLE in Caucasians (OR = 0.737, 95% CI = 0.673-0.808, p rheumatic diseases in Caucasians (OR = 0.812, 95% CI = 0.661-0.997, p = 0.046) but not in Asians. Interestingly, the rs280519 polymorphism was significantly associated with susceptibility to SLE both in Caucasians and Asians. However, no associations were found between the rs12720270, rs280500, rs280523 and rs8108236 polymorphisms and susceptibility to rheumatic diseases. This meta-analysis demonstrates that the TYK2 rs2304256 and rs12720356 polymorphisms are associated with susceptibility to rheumatic diseases, rs2304256 polymorphism is associated with SLE in Caucasians, and rs280519 polymorphism is associated with SLE in Caucasians and Asians. © The Author(s) 2016.

META-ANALYSIS: THE WAY FORWARD IN MEDICAL DISCOVERY

African Journals Online (AJOL)

data, and (6) report the results. Define the Research Question. A meta-analysis begins with a question. Common questions addressed in meta-analyses are whether one. META-ANALYSIS: THE WAY FORWARD IN MEDICAL DISCOVERY. Akinyemi J.O. MSc (Medical Statistics), B Tech (Comp. Sc.) Correspondence:.

The impact of pneumatic tube system on routine laboratory parameters: a systematic review and meta-analysis.

Science.gov (United States)

Kapoula, Georgia V; Kontou, Panagiota I; Bagos, Pantelis G

2017-10-26

Pneumatic tube system (PTS) is a widely used method of transporting blood samples in hospitals. The aim of this study was to evaluate the effects of the PTS transport in certain routine laboratory parameters as it has been implicated with hemolysis. A systematic review and a meta-analysis were conducted. PubMed and Scopus databases were searched (up until November 2016) to identify prospective studies evaluating the impact of PTS transport in hematological, biochemical and coagulation measurements. The random-effects model was used in the meta-analysis utilizing the mean difference (MD). Heterogeneity was quantitatively assessed using the Cohran's Q and the I2 index. Subgroup analysis, meta-regression analysis, sensitivity analysis, cumulative meta-analysis and assessment of publication bias were performed for all outcomes. From a total of 282 studies identified by the searching procedure, 24 were finally included in the meta-analysis. The meta-analysis yielded statistically significant results for potassium (K) [MD=0.04 mmol/L; 95% confidence interval (CI)=0.015-0.065; p=0.002], lactate dehydrogenase (LDH) (MD=10.343 U/L; 95% CI=6.132-14.554; panalysis and random-effects meta-regression analysis according to the speed and distance of the samples traveled via the PTS revealed that there is relation between the rate and the distance of PTS with the measurements of K, LDH, white blood cells and red blood cells. This meta-analysis suggests that PTS may be associated with alterations in K, LDH and AST measurements. Although these findings may not have any significant clinical effect on laboratory results, it is wise that each hospital validates their PTS.

Meta-Analysis in Stata Using Gllamm

Science.gov (United States)

Bagos, Pantelis G.

2015-01-01

There are several user-written programs for performing meta-analysis in Stata (Stata Statistical Software: College Station, TX: Stata Corp LP). These include metan, metareg, mvmeta, and glst. However, there are several cases for which these programs do not suffice. For instance, there is no software for performing univariate meta-analysis with…

Elevated alanine aminotransferase is strongly associated with incident metabolic syndrome: a meta-analysis of prospective studies.

Directory of Open Access Journals (Sweden)

Zhengtao Liu

Full Text Available BACKGROUND: The incidence of metabolic syndrome (MetS is rapidly increasing worldwide and associated with alanine aminotransferase (ALT activity. However, the impact of ALT activity on MetS incidence is inconsistent in published literature. We therefore estimated the association between elevated ALT activity and incident MetS through a meta-analysis of prospective cohort studies. METHODS/PRINCIPAL FINDINGS: All published prospective cohort studies on the association between elevated ALT activity and incident MetS were retrieved from Pubmed, Embase, and the Institute for Scientific Information (ISI. In all, seven prospective cohort studies, with 31545 participants and 2873 cases of incident MetS were recruited. If there was insignificant heterogeneity (P-value>0.05 and I(2<50%, the fixed-effect model was used to calculate the pooled relative risks (RRs of incident MetS induced by raised ALT. Otherwise, the random-effect model was used. The calculated RR was 1.81 (95% confidence interval [CI]: 1.49-2.14 when the incidence of MetS was compared between the highest versus the lowest classification of ALT activities. The pooled RR was 1.13 (95% CI: 1.11-1.16 in dose-response analysis with 5 units per liter (U/l of ALT increment. Subgroup analysis suggested that gender disparity might be the main origin of heterogeneity in overall analysis (P = 0.007 between RRs of gender-specific subgroups evaluated with 5 U/l increments of ALT. Women had a higher dose-response risk of MetS incidence (1.38, 95% CI: 1.20-1.55 than men. Furthermore, sensitivity analysis confirmed the stability of results. No publication bias was found in our meta-analysis. CONCLUSIONS/SIGNIFICANCE: Current evidence from prospective studies supports the association between ALT elevation and increasing MetS incidence. This association is closer and more consistent in female population. Further studies are needed to confirm this association and to investigate the potential mechanism of

Effectiveness of Various Innovative Learning Methods in Health Science Classrooms: A Meta-Analysis

Science.gov (United States)

Kalaian, Sema A.; Kasim, Rafa M.

2017-01-01

This study reports the results of a meta-analysis of the available literature on the effectiveness of various forms of innovative small-group learning methods on student achievement in undergraduate college health science classrooms. The results of the analysis revealed that most of the primary studies supported the effectiveness of the…

The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses.

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Xie, Heping; Wang, Fuxing; Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

2017-01-01

Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = -0.11, 95% CI = [-0.19, -0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = -0.70, 95% CI = [-1.02, -0.38], p < 0.001), as well as dtransfer for cueing (β = -0.60, 95% CI = [-0.92, -0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning.

Using structural equation modeling for network meta-analysis.

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Tu, Yu-Kang; Wu, Yun-Chun

2017-07-14

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

Meta-Analysis of Coefficient Alpha

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Rodriguez, Michael C.; Maeda, Yukiko

2006-01-01

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

A Meta-Analysis for the Efficacy of Hypnotherapy in Alleviating PTSD Symptoms.

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Rotaru, Tudor-Ștefan; Rusu, Andrei

2016-01-01

A systematic review and meta-analysis of the efficacy of hypnotherapy in the treatment of PTSD used literature searches to obtain 47 articles. However, only 6 were experiments testing the efficacy of hypnosis-based treatments. A fixed-effects meta-analysis was applied to postintervention assessment results and 4-week follow-ups. A large effect in favor of hypnosis-based (especially manualized abreactive hypnosis) treatment was found for the studies that reported the posttest results (d = 1.17). The temporal stability of the effect remains strong, as reflected by the 4-week follow-up assessments (d = 1.58) and also by long-term evaluations (e.g., 12 months). Hypnosis appears to be effective in alleviating PTSD symptoms.

Data analysis with the DIANA meta-scheduling approach

International Nuclear Information System (INIS)

Anjum, A; McClatchey, R; Willers, I

2008-01-01

The concepts, design and evaluation of the Data Intensive and Network Aware (DIANA) meta-scheduling approach for solving the challenges of data analysis being faced by CERN experiments are discussed in this paper. Our results suggest that data analysis can be made robust by employing fault tolerant and decentralized meta-scheduling algorithms supported in our DIANA meta-scheduler. The DIANA meta-scheduler supports data intensive bulk scheduling, is network aware and follows a policy centric meta-scheduling. In this paper, we demonstrate that a decentralized and dynamic meta-scheduling approach is an effective strategy to cope with increasing numbers of users, jobs and datasets. We present 'quality of service' related statistics for physics analysis through the application of a policy centric fair-share scheduling model. The DIANA meta-schedulers create a peer-to-peer hierarchy of schedulers to accomplish resource management that changes with evolving loads and is dynamic and adapts to the volatile nature of the resources

Integrative multi-platform meta-analysis of gene expression profiles in pancreatic ductal adenocarcinoma patients for identifying novel diagnostic biomarkers.

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Irigoyen, Antonio; Jimenez-Luna, Cristina; Benavides, Manuel; Caba, Octavio; Gallego, Javier; Ortuño, Francisco Manuel; Guillen-Ponce, Carmen; Rojas, Ignacio; Aranda, Enrique; Torres, Carolina; Prados, Jose

2018-01-01

Applying differentially expressed genes (DEGs) to identify feasible biomarkers in diseases can be a hard task when working with heterogeneous datasets. Expression data are strongly influenced by technology, sample preparation processes, and/or labeling methods. The proliferation of different microarray platforms for measuring gene expression increases the need to develop models able to compare their results, especially when different technologies can lead to signal values that vary greatly. Integrative meta-analysis can significantly improve the reliability and robustness of DEG detection. The objective of this work was to develop an integrative approach for identifying potential cancer biomarkers by integrating gene expression data from two different platforms. Pancreatic ductal adenocarcinoma (PDAC), where there is an urgent need to find new biomarkers due its late diagnosis, is an ideal candidate for testing this technology. Expression data from two different datasets, namely Affymetrix and Illumina (18 and 36 PDAC patients, respectively), as well as from 18 healthy controls, was used for this study. A meta-analysis based on an empirical Bayesian methodology (ComBat) was then proposed to integrate these datasets. DEGs were finally identified from the integrated data by using the statistical programming language R. After our integrative meta-analysis, 5 genes were commonly identified within the individual analyses of the independent datasets. Also, 28 novel genes that were not reported by the individual analyses ('gained' genes) were also discovered. Several of these gained genes have been already related to other gastroenterological tumors. The proposed integrative meta-analysis has revealed novel DEGs that may play an important role in PDAC and could be potential biomarkers for diagnosing the disease.

Processes that Inform Multicultural Supervision: A Qualitative Meta-Analysis.

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Tohidian, Nilou B; Quek, Karen Mui-Teng

2017-10-01

As the fields of counseling and psychotherapy have become more cognizant that individuals, couples, and families bring with them a myriad of diversity factors into therapy, multicultural competency has also become a crucial component in the development of clinicians during clinical supervision and training. We employed a qualitative meta-analysis to provide a detailed and comprehensive description of similar themes identified in primary qualitative studies that have investigated supervisory practices with an emphasis on diversity. Findings revealed six meta-categories, namely: (a) Supervisor's Multicultural Stances; (b) Supervisee's Multicultural Encounters; (c) Competency-Based Content in Supervision; (d) Processes Surrounding Multicultural Supervision; (e) Culturally Attuned Interventions; and (f) Multicultural Supervisory Alliance. Implications for practice are discussed. © 2017 American Association for Marriage and Family Therapy.

Discrimination against Latina/os: A Meta-Analysis of Individual-Level Resources and Outcomes

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Lee, Debbiesiu L.; Ahn, Soyeon

2012-01-01

This meta-analysis synthesizes the findings of 60 independent samples from 51 studies examining racial/ethnic discrimination against Latina/os in the United States. The purpose was to identify individual-level resources and outcomes that most strongly relate to discrimination. Discrimination against Latina/os significantly results in outcomes…

Multivariate Methods for Meta-Analysis of Genetic Association Studies.

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

2018-01-01

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

Meta-analysis of genome-wide association studies discovers multiple loci for chronic lymphocytic leukemia

NARCIS (Netherlands)

Berndt, Sonja I; Camp, Nicola J; Skibola, Christine F; Vijai, Joseph; Wang, Zhaoming; Gu, Jian; Nieters, Alexandra; Kelly, Rachel S; Smedby, Karin E; Monnereau, Alain; Cozen, Wendy; Cox, Angela; Wang, Sophia S; Lan, Qing; Teras, Lauren R; Machado, Moara; Yeager, Meredith; Brooks-Wilson, Angela R; Hartge, Patricia; Purdue, Mark P; Birmann, Brenda M; Vajdic, Claire M; Cocco, Pierluigi; Zhang, Yawei; Giles, Graham G; Zeleniuch-Jacquotte, Anne; Lawrence, Charles; Montalvan, Rebecca; Burdett, Laurie; Hutchinson, Amy; Ye, Yuanqing; Call, Timothy G; Shanafelt, Tait D; Novak, Anne J; Kay, Neil E; Liebow, Mark; Cunningham, Julie M; Allmer, Cristine; Hjalgrim, Henrik; Adami, Hans-Olov; Melbye, Mads; Glimelius, Bengt; Chang, Ellen T; Glenn, Martha; Curtin, Karen; Cannon-Albright, Lisa A; Diver, W Ryan; Link, Brian K; Weiner, George J; Conde, Lucia; Bracci, Paige M; Riby, Jacques; Arnett, Donna K; Zhi, Degui; Leach, Justin M; Holly, Elizabeth A; Jackson, Rebecca D; Tinker, Lesley F; Benavente, Yolanda; Sala, Núria; Casabonne, Delphine; Becker, Nikolaus; Boffetta, Paolo; Brennan, Paul; Foretova, Lenka; Maynadie, Marc; McKay, James; Staines, Anthony; Chaffee, Kari G; Achenbach, Sara J; Vachon, Celine M; Goldin, Lynn R; Strom, Sara S; Leis, Jose F; Weinberg, J Brice; Caporaso, Neil E; Norman, Aaron D; De Roos, Anneclaire J; Morton, Lindsay M; Severson, Richard K; Riboli, Elio; Vineis, Paolo; Kaaks, Rudolph; Masala, Giovanna; Weiderpass, Elisabete; Chirlaque, María-Dolores; Vermeulen, Roel C H|info:eu-repo/dai/nl/216532620; Travis, Ruth C; Southey, Melissa C; Milne, Roger L; Albanes, Demetrius; Virtamo, Jarmo; Weinstein, Stephanie; Clavel, Jacqueline; Zheng, Tongzhang; Holford, Theodore R; Villano, Danylo J; Maria, Ann; Spinelli, John J; Gascoyne, Randy D; Connors, Joseph M; Bertrand, Kimberly A; Giovannucci, Edward; Kraft, Peter; Kricker, Anne; Turner, Jenny; Ennas, Maria Grazia; Ferri, Giovanni M; Miligi, Lucia; Liang, Liming; Ma, Baoshan; Huang, Jinyan; Crouch, Simon; Park, Ju-Hyun; Chatterjee, Nilanjan; North, Kari E; Snowden, John A; Wright, Josh; Fraumeni, Joseph F; Offit, Kenneth; Wu, Xifeng; de Sanjose, Silvia; Cerhan, James R; Chanock, Stephen J; Rothman, Nathaniel; Slager, Susan L

2016-01-01

Chronic lymphocytic leukemia (CLL) is a common lymphoid malignancy with strong heritability. To further understand the genetic susceptibility for CLL and identify common loci associated with risk, we conducted a meta-analysis of four genome-wide association studies (GWAS) composed of 3,100 cases and

a meta-analysis

Indian Academy of Sciences (India)

Chrissa G. Tsiara

2018-03-13

Mar 13, 2018 ... a meta-analysis of case–control studies was conducted. Univariate and ...... recent hepatitis C virus: potential benefit for ribavirin use in. HCV/HIV ... C/G polymorphism in breast pathologies and in HIV-infected patients.

Indirect health costs in ulcerative colitis and Crohn's disease: a systematic review and meta-analysis.

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Kawalec, Paweł; Malinowski, Krzysztof Piotr

2015-04-01

The aim of this systematic review was to collect all current data on indirect costs related to inflammatory bowel disease as well as assessing homogeneity and comparability, and conducting a meta-analysis. Costs were collected using databases from Medline, Embase and Centre for Reviews and Dissemination databases, then average annual cost per patient was calculated and expressed in 2013-rate USD using the consumer price index and purchasing power parity (scenario 1) and then adjusted to specific gross domestic product (scenario 2) to make them comparable. The studies were then included in quantitative synthesis using the meta-analysis and bootstrap methods. This systematic review was carried out and reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. From 18 publications, overall annual indirect costs per patient as a result of the quantitative synthesis among all studies eligible for meta-analysis ranged from US$2425.01-US$9622.15 depending on the scenario and model used for analysis. The cost of presenteeism was assessed in only two studies. Considering heterogeneity among all identified studies random-effect model presented the most accurate results of meta-analysis equal to US$7189.27 and US$9622.15 per patient per year for scenario 1 and scenario 2, respectively. This systematic review revealed the existence of a relatively small number of studies that reported on the great economic burden of the disease upon society. A great variety of methodologies and cost components resulted in a very large discrepancy in indirect costs and made meta-analysis difficult to perform, so two scenarios were considered and meta-analysis conducted in subgroups to make data more comparable.

Narcissism and Social Networking Behavior: A Meta-Analysis.

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Gnambs, Timo; Appel, Markus

2018-04-01

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

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

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Köpcke, Wolfgang; Krutmann, Jean

2008-01-01

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

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

Science.gov (United States)

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

2018-01-01

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

Diagnostic imaging for chronic plantar heel pain: a systematic review and meta-analysis

Directory of Open Access Journals (Sweden)

Barrett Joanna T

2009-11-01

Full Text Available Abstract Background Chronic plantar heel pain (CPHP is a generalised term used to describe a range of undifferentiated conditions affecting the plantar heel. Plantar fasciitis is reported as the most common cause and the terms are frequently used interchangeably in the literature. Diagnostic imaging has been used by many researchers and practitioners to investigate the involvement of specific anatomical structures in CPHP. These observations help to explain the underlying pathology of the disorder, and are of benefit in forming an accurate diagnosis and targeted treatment plan. The purpose of this systematic review was to investigate the diagnostic imaging features associated with CPHP, and evaluate study findings by meta-analysis where appropriate. Methods Bibliographic databases including Medline, Embase, CINAHL, SportDiscus and The Cochrane Library were searched electronically on March 25, 2009. Eligible articles were required to report imaging findings in participants with CPHP unrelated to inflammatory arthritis, and to compare these findings with a control group. Methodological quality was evaluated by use of the Quality Index as described by Downs and Black. Meta-analysis of study data was conducted where appropriate. Results Plantar fascia thickness as measured by ultrasonography was the most widely reported imaging feature. Meta-analysis revealed that the plantar fascia of CPHP participants was 2.16 mm thicker than control participants (95% CI = 1.60 to 2.71 mm, P P = 0.01. CPHP participants were also more likely to show radiographic evidence of subcalcaneal spur than control participants (OR = 8.52, 95% CI = 4.08 to 17.77, P Conclusion This systematic review has identified 23 studies investigating the diagnostic imaging appearance of the plantar fascia and inferior calcaneum in people with CPHP. Analysis of these studies found that people with CPHP are likely to have a thickened plantar fascia with associated fluid collection, and that

Diagnostic imaging for chronic plantar heel pain: a systematic review and meta-analysis

Science.gov (United States)

2009-01-01

Background Chronic plantar heel pain (CPHP) is a generalised term used to describe a range of undifferentiated conditions affecting the plantar heel. Plantar fasciitis is reported as the most common cause and the terms are frequently used interchangeably in the literature. Diagnostic imaging has been used by many researchers and practitioners to investigate the involvement of specific anatomical structures in CPHP. These observations help to explain the underlying pathology of the disorder, and are of benefit in forming an accurate diagnosis and targeted treatment plan. The purpose of this systematic review was to investigate the diagnostic imaging features associated with CPHP, and evaluate study findings by meta-analysis where appropriate. Methods Bibliographic databases including Medline, Embase, CINAHL, SportDiscus and The Cochrane Library were searched electronically on March 25, 2009. Eligible articles were required to report imaging findings in participants with CPHP unrelated to inflammatory arthritis, and to compare these findings with a control group. Methodological quality was evaluated by use of the Quality Index as described by Downs and Black. Meta-analysis of study data was conducted where appropriate. Results Plantar fascia thickness as measured by ultrasonography was the most widely reported imaging feature. Meta-analysis revealed that the plantar fascia of CPHP participants was 2.16 mm thicker than control participants (95% CI = 1.60 to 2.71 mm, P plantar fascia thickness values greater than 4.0 mm (OR = 105.11, 95% CI = 3.09 to 3577.28, P = 0.01). CPHP participants were also more likely to show radiographic evidence of subcalcaneal spur than control participants (OR = 8.52, 95% CI = 4.08 to 17.77, P plantar fascia and inferior calcaneum in people with CPHP. Analysis of these studies found that people with CPHP are likely to have a thickened plantar fascia with associated fluid collection, and that thickness values >4.0 mm are diagnostic of

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

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

2017-07-19

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

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

Directory of Open Access Journals (Sweden)

Yusuke Yamaguchi

2017-07-01

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

Online Open Neuroimaging Mass Meta-Analysis with a Wiki

DEFF Research Database (Denmark)

Nielsen, Finn Arup; Kempton, Matthew J.; Williams, Steven C. R.

2015-01-01

We describe a system for meta-analysis where a wiki stores numerical data in a simple comma-separated values format and a web service performs the numerical statistical computation. We initially apply the system on multiple meta-analyses of structural neuroimaging data results. The described system...... allows for mass meta-analysis, e.g., meta-analysis across multiple brain regions and multiple mental disorders providing an overview of important relationships and their uncertainties in a collaborative environment....

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

Energy Technology Data Exchange (ETDEWEB)

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

2006-05-01

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

Meta-analysis in clinical trials revisited.

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DerSimonian, Rebecca; Laird, Nan

2015-11-01

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

Meta-analysis reveals an association of STAT4 polymorphisms with systemic autoimmune disorders and anti-dsDNA antibody.

Science.gov (United States)

Zheng, Junfeng; Yin, Junping; Huang, Renliang; Petersen, Frank; Yu, Xinhua

2013-08-01

Signal transducer and activator of transcription 4 (STAT4) has been recently identified as a susceptibility gene for multiple autoimmune diseases. Here we performed a comprehensive analysis of the association between STAT4 and several different autoimmune disorders to identify potential common inflammatory principles behind this association. Our meta-analysis revealed that the STAT4 rs7574865 polymorphism is associated with four autoimmune diseases with systemic pathology, including systemic lupus erythematosus (OR = 1.52; 95% CI = 1.48 - 1.56, Prs7574865 polymorphism is associated with the presence of autoantibodies with systemic reactivity (anti-ds-DNA antibodies) in SLE patients (OR = 1.37; 95% CI = 1.21 - 1.56, P = 1.12 × 10(-6)). However, no such specific association was seen in RA with regard to the presence of non-systemically reacting antibodies, including rheumatoid factor and anti-cyclic citrullinated peptide antibodies. Taken together, these results suggest that STAT4 polymorphisms are associated with autoimmune diseases which are characterized by a systemic pathology and anti-dsDNA antibody. Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Evaluating the Quality of Evidence from a Network Meta-Analysis

Science.gov (United States)

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

2014-01-01

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

Personality and Parkinson's disease: A meta-analysis.

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Santangelo, Gabriella; Garramone, Federica; Baiano, Chiara; D'Iorio, Alfonsina; Piscopo, Fausta; Raimo, Simona; Vitale, Carmine

2018-04-01

Personality changes are considered pre-motor features of Parkinson's disease (PD). Cross-sectional studies revealed that PD patients were more introvert, apprehensive, and cautious than healthy subjects (HS), whereas other studies failed to disclose these behavioural traits. Some studies found mixed results concerning Novelty Seeking (NS) and Harm Avoidance (HA) profiles in PD patients. To better clarify the personality profile in PD we performed a meta-analysis on studies exploring such topic according to both Cloninger's Psychobiological Model (PM) and Big Five Model (BFM) METHODS: The meta-analysis included 17 studies evaluating the personality in PD patients compared with HS. The outcomes were the dimensions of the temperament and character of the PM and personality traits of BFM. Effect sizes from data reported in the primary studies were computed using Hedges'g unbiased approach. Heterogeneity among the studies and publication bias were assessed. Meta-regressions were conducted with age at evaluation, gender, schooling, and type of personality trait tools as moderators. As for PM, PD patients scored higher on HA and lower on NS than HS. No difference was found on Reward Dependence, Perseverance/Persistence and on character level. As for BFM, higher levels of Neuroticism, but lower levels of Openness and Extraversion were associated with PD. The personality profile in PD is characterized by high Neuroticism and HA, and by low Openness, Extraversion and NS. The personality profile delineated in the present study on PD patients seems to reflect the premorbid one and might contribute to development and persistence of affective disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

Physical activity and risk of pancreatic cancer: a systematic review and meta-analysis.

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Behrens, Gundula; Jochem, Carmen; Schmid, Daniela; Keimling, Marlen; Ricci, Cristian; Leitzmann, Michael F

2015-04-01

Physical activity may prevent pancreatic cancer by regulating body weight and decreasing insulin resistance, DNA damage, and chronic inflammation. Previous meta-analyses found inconsistent evidence for a protective effect of physical activity on pancreatic cancer but those studies did not investigate whether the association between physical activity and pancreatic cancer varies by smoking status, body mass index (BMI), or level of consistency of physical activity over time. To address these issues, we conducted an updated meta-analysis following the PRISMA guidelines among 30 distinct studies with a total of 10,501 pancreatic cancer cases. Random effects meta-analysis of cohort studies revealed a weak, statistically significant reduction in pancreatic cancer risk for high versus low levels of physical activity (relative risk (RR) 0.93, 95 % confidence interval (CI) 0.88-0.98). By comparison, case-control studies yielded a stronger, statistically significant risk reduction (RR 0.78, 95 % CI 0.66-0.94; p-difference by study design = 0.07). When focusing on cohort studies, physical activity summary risk estimates appeared to be more pronounced for consistent physical activity over time (RR 0.86, 95 % CI 0.76-0.97) than for recent past physical activity (RR 0.95, 95 % CI 0.90-1.01) or distant past physical activity (RR 0.95, 95 % CI 0.79-1.15, p-difference by timing in life of physical activity = 0.36). Physical activity summary risk estimates did not differ by smoking status or BMI. In conclusion, physical activity is not strongly associated with pancreatic cancer risk, and the relation is not modified by smoking status or BMI level. While overall findings were weak, we did find some suggestion of potential pancreatic cancer risk reduction with consistent physical activity over time.

Advances in meta-analysis: examples from internal medicine to neurology.

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Copetti, Massimiliano; Fontana, Andrea; Graziano, Giusi; Veneziani, Federica; Siena, Federica; Scardapane, Marco; Lucisano, Giuseppe; Pellegrini, Fabio

2014-01-01

We review the state of the art in meta-analysis and data pooling following the evolution of the statistical models employed. Starting from a classic definition of meta-analysis of published data, a set of apparent antinomies which characterized the development of the meta-analytic tools are reconciled in dichotomies where the second term represents a possible generalization of the first one. Particular attention is given to the generalized linear mixed models as an overall framework for meta-analysis. Bayesian meta-analysis is discussed as a further possibility of generalization for sensitivity analysis and the use of priors as a data augmentation approach. We provide relevant examples to underline how the need for adequate methods to solve practical issues in specific areas of research have guided the development of advanced methods in meta-analysis. We show how all the advances in meta-analysis naturally merge into the unified framework of generalized linear mixed models and reconcile apparently conflicting approaches. All these complex models can be easily implemented with the standard commercial software available. © 2013 S. Karger AG, Basel.

The effects of aromatherapy on sleep improvement: a systematic literature review and meta-analysis.

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Hwang, Eunhee; Shin, Sujin

2015-02-01

To evaluate the existing data on aromatherapy interventions for improvement of sleep quality. Systematic literature review and meta-analysis on the effects of aromatherapy. Study Sources: Electronic databases, including the Korea Education and Research Information Service (KERIS), Korean studies Information Service System (KISS), National Assembly Library, and eight academies within the Korean Society of Nursing Science, were searched to identify studies published between 2000 and August 2013. Randomized controlled and quasi-experimental trials that included aromatherapy for the improvement of sleep quality. Of the 245 publications identified, 13 studies met the inclusion and exclusion criteria, and 12 studies were used in the meta-analysis. Meta-analysis of the 12 studies using a random-effects model revealed that the use of aromatherapy was effective in improving sleep quality (95% confidence interval [CI], 0.540-1.745; Z=3.716). Subgroup analysis revealed that inhalation aromatherapy (95% CI, 0.792-1.541; Z=6.107) was more effective than massage therapy (95% CI, 0.128-2.166; Z=2.205) in unhealthy (95% CI, 0.248-1.100; Z=3.100) and healthy (95% CI, 0.393-5.104; Z=2.287) participants, respectively. Readily available aromatherapy treatments appear to be effective and promote sleep. Thus, it is essential to develop specific guidelines for the efficient use of aromatherapy.

Drivers of wetland conversion: a global meta-analysis.

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van Asselen, Sanneke; Verburg, Peter H; Vermaat, Jan E; Janse, Jan H

2013-01-01

Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis of the proximate causes and underlying forces of wetland conversion at a global scale using two complementary approaches of systematic review. Firstly, a meta-analysis of 105 case-study papers describing wetland conversion was performed, showing that different combinations of multiple-factor proximate causes, and underlying forces, drive wetland conversion. Agricultural development has been the main proximate cause of wetland conversion, and economic growth and population density are the most frequently identified underlying forces. Secondly, to add a more quantitative component to the study, a logistic meta-regression analysis was performed to estimate the likelihood of wetland conversion worldwide, using globally-consistent biophysical and socioeconomic location factor maps. Significant factors explaining wetland conversion, in order of importance, are market influence, total wetland area (lower conversion probability), mean annual temperature and cropland or built-up area. The regression analyses results support the outcomes of the meta-analysis of the processes of conversion mentioned in the individual case studies. In other meta-analyses of land change, similar factors (e.g., agricultural development, population growth, market/economic factors) are also identified as important causes of various types of land change (e.g., deforestation, desertification). Meta-analysis helps to identify commonalities across the various local case studies and identify which variables may lead to individual cases to behave differently. The meta-regression provides maps indicating the likelihood of wetland conversion worldwide based on the location factors that have determined historic

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

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Hande Küçükönder

2014-09-01

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

The potential for meta-analysis to support decision analysis in ecology.

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Mengersen, Kerrie; MacNeil, M Aaron; Caley, M Julian

2015-06-01

Meta-analysis and decision analysis are underpinned by well-developed methods that are commonly applied to a variety of problems and disciplines. While these two fields have been closely linked in some disciplines such as medicine, comparatively little attention has been paid to the potential benefits of linking them in ecology, despite reasonable expectations that benefits would be derived from doing so. Meta-analysis combines information from multiple studies to provide more accurate parameter estimates and to reduce the uncertainty surrounding them. Decision analysis involves selecting among alternative choices using statistical information that helps to shed light on the uncertainties involved. By linking meta-analysis to decision analysis, improved decisions can be made, with quantification of the costs and benefits of alternate decisions supported by a greater density of information. Here, we briefly review concepts of both meta-analysis and decision analysis, illustrating the natural linkage between them and the benefits from explicitly linking one to the other. We discuss some examples in which this linkage has been exploited in the medical arena and how improvements in precision and reduction of structural uncertainty inherent in a meta-analysis can provide substantive improvements to decision analysis outcomes by reducing uncertainty in expected loss and maximising information from across studies. We then argue that these significant benefits could be translated to ecology, in particular to the problem of making optimal ecological decisions in the face of uncertainty. Copyright © 2013 John Wiley & Sons, Ltd.

Longitudinal analysis of meta-analysis literatures in the database of ISI Web of Science.

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Zhu, Changtai; Jiang, Ting; Cao, Hao; Sun, Wenguang; Chen, Zhong; Liu, Jinming

2015-01-01

The meta-analysis is regarded as an important evidence for making scientific decision. The database of ISI Web of Science collected a great number of high quality literatures including meta-analysis literatures. However, it is significant to understand the general characteristics of meta-analysis literatures to outline the perspective of meta-analysis. In this present study, we summarized and clarified some features on these literatures in the database of ISI Web of Science. We retrieved the meta-analysis literatures in the database of ISI Web of Science including SCI-E, SSCI, A&HCI, CPCI-S, CPCI-SSH, CCR-E, and IC. The annual growth rate, literature category, language, funding, index citation, agencies and countries/territories of the meta-analysis literatures were analyzed, respectively. A total of 95,719 records, which account for 0.38% (99% CI: 0.38%-0.39%) of all literatures, were found in the database. From 1997 to 2012, the annual growth rate of meta-analysis literatures was 18.18%. The literatures involved in many categories, languages, fundings, citations, publication agencies, and countries/territories. Interestingly, the index citation frequencies of the meta-analysis were significantly higher than that of other type literatures such as multi-centre study, randomize controlled trial, cohort study, case control study, and cases report (Panalysis has been becoming more and more prominent in recent years. In future, in order to promote the validity of meta-analysis, the CONSORT and PRISMA standard should be continuously popularized in the field of evidence-based medicine.

A Karnaugh map based approach towards systemic reviews and meta-analysis.

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Hassan, Abdul Wahab; Hassan, Ahmad Kamal

2016-01-01

Studying meta-analysis and systemic reviews since long had helped us conclude numerous parallel or conflicting studies. Existing studies are presented in tabulated forms which contain appropriate information for specific cases yet it is difficult to visualize. On meta-analysis of data, this can lead to absorption and subsumption errors henceforth having undesirable potential of consecutive misunderstandings in social and operational methodologies. The purpose of this study is to investigate an alternate forum for meta-data presentation that relies on humans' strong pictorial perception capability. Analysis of big-data is assumed to be a complex and daunting task often reserved on the computational powers of machines yet there exist mapping tools which can analyze such data in a hand-handled manner. Data analysis on such scale can benefit from the use of statistical tools like Karnaugh maps where all studies can be put together on a graph based mapping. Such a formulation can lead to more control in observing patterns of research community and analyzing further for uncertainty and reliability metrics. We present a methodological process of converting a well-established study in Health care to its equaling binary representation followed by furnishing values on to a Karnaugh Map. The data used for the studies presented herein is from Burns et al (J Publ Health 34(1):138-148, 2011) consisting of retrospectively collected data sets from various studies on clinical coding data accuracy. Using a customized filtration process, a total of 25 studies were selected for review with no, partial, or complete knowledge of six independent variables thus forming 64 independent cells on a Karnaugh map. The study concluded that this pictorial graphing as expected had helped in simplifying the overview of meta-analysis and systemic reviews.

The Influence of Judgment Calls on Meta-Analytic Findings.

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Tarrahi, Farid; Eisend, Martin

2016-01-01

Previous research has suggested that judgment calls (i.e., methodological choices made in the process of conducting a meta-analysis) have a strong influence on meta-analytic findings and question their robustness. However, prior research applies case study comparison or reanalysis of a few meta-analyses with a focus on a few selected judgment calls. These studies neglect the fact that different judgment calls are related to each other and simultaneously influence the outcomes of a meta-analysis, and that meta-analytic findings can vary due to non-judgment call differences between meta-analyses (e.g., variations of effects over time). The current study analyzes the influence of 13 judgment calls in 176 meta-analyses in marketing research by applying a multivariate, multilevel meta-meta-analysis. The analysis considers simultaneous influences from different judgment calls on meta-analytic effect sizes and controls for alternative explanations based on non-judgment call differences between meta-analyses. The findings suggest that judgment calls have only a minor influence on meta-analytic findings, whereas non-judgment call differences between meta-analyses are more likely to explain differences in meta-analytic findings. The findings support the robustness of meta-analytic results and conclusions.

Learning with STEM Simulations in the Classroom: Findings and Trends from a Meta-Analysis

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D'Angelo, Cynthia M.; Rutstein, Daisy; Harris, Christopher J.

2016-01-01

This article presents a summary of the findings of a systematic review and meta-analysis of the literature on computer-based interactive simulations for K-12 science, technology, engineering, and mathematics (STEM) learning topics. For achievement outcomes, simulations had a moderate to strong effect on student learning. Overall, simulations have…

Multivariate meta-analysis: Potential and promise

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

2011-01-01

The multivariate random effects model is a generalization of the standard univariate model. Multivariate meta-analysis is becoming more commonly used and the techniques and related computer software, although continually under development, are now in place. In order to raise awareness of the multivariate methods, and discuss their advantages and disadvantages, we organized a one day ‘Multivariate meta-analysis’ event at the Royal Statistical Society. In addition to disseminating the most recent developments, we also received an abundance of comments, concerns, insights, critiques and encouragement. This article provides a balanced account of the day's discourse. By giving others the opportunity to respond to our assessment, we hope to ensure that the various view points and opinions are aired before multivariate meta-analysis simply becomes another widely used de facto method without any proper consideration of it by the medical statistics community. We describe the areas of application that multivariate meta-analysis has found, the methods available, the difficulties typically encountered and the arguments for and against the multivariate methods, using four representative but contrasting examples. We conclude that the multivariate methods can be useful, and in particular can provide estimates with better statistical properties, but also that these benefits come at the price of making more assumptions which do not result in better inference in every case. Although there is evidence that multivariate meta-analysis has considerable potential, it must be even more carefully applied than its univariate counterpart in practice. Copyright © 2011 John Wiley & Sons, Ltd. PMID:21268052

Prevalence of premenstrual syndrome in Iran: A systematic review and meta-analysis

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Mehdi Ranjbaran

2017-11-01

Full Text Available Background: Premenstrual syndrome (PMS is a common disorder characterized by physical, mental and behavioral changes in the luteal phase of the menstrual cycle in the reproductive age women. Objective: The present study aimed to determine the overall prevalence of PMS in Iran by a systematic review and meta-analysis study. Materials and Methods: In this systematic review and meta-analysis, we searched international databases included ISI Web of Knowledge, PubMed/Medline, Scopus, Google Scholar, and also local databases including Iranmedex, Scientific Information Database, and Magiran for articles in English and Persian language published up to September 2016. We carried out data analysis with Stata version 11. We examined heterogeneity in the results of studies through I2 statistics and Chi-square based Q test. Also, we investigated the effects of potential heterogeneity factors in the prevalence of PMS by meta-regression. Results: We studied a total of 9147 reproductive-age women from 24 articles which entered to meta-analysis. Based on the result of random effect model, we estimated the overall prevalence of PMS 70.8% [95% CI: 63.8-77.7]. The results of subgroup analysis revealed that prevalence of PMS was 80.4% (95% CI; 66.9-93.9 among high school students, 68.9% (95% CI; 59.2-78.6 among university students, and 54.9% (95% CI; 51.6-58.2 in general population. Univariate meta-regression model showed that prevalence of PMS was decreased by increasing the age of subjects but this was not statistically significant (p=0.155. Conclusion: Our finding showed that PMS was prevalent in Iranian reproductive age women especially among high school students. More epidemiological research for determining factors that affect PMS prevalence seems essential.

The relationship between serum lipids and sudden sensorineural hearing loss: a systematic review and meta-analysis.

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I Jen Chang

Full Text Available Sudden sensorineural hearing loss (SSNHL is a relatively common condition that is usually of unknown etiology. A number of individual studies have investigated the association between various serum lipids and SSNHL; however, the findings have been inconsistent. In an attempt to obtain more definitive information on the relationship between serum lipids and SSNHL, we carried out a systematic review and meta-analysis.Medline, the Cochrane Library, and EMBASE were searched using the following key words: lipid, cholesterol, triglyceride, fat, serum, blood, sudden hearing loss, hearing loss, hearing disorders. Randomized controlled trials, prospective cohort studies, and retrospective case-control studies involving patients with SSNHL and healthy controls that examined the relationship (reported as odds ratios [OR] between lipid profiles and SSNHL were included. Primary outcomes were total cholesterol and low-density lipoprotein cholesterol (LDL-C concentrations. Secondary outcomes were triglyceride, high-density lipoprotein cholesterol, and lipoprotein(a concentrations.A total of 6 case-control studies were included in this systematic review/meta-analysis. The total number of participants ranged from 30 to 250 in the case group and from 43 to 271 in the control group. Meta-analysis revealed no significant difference in total cholesterol levels between the case and control groups (pooled OR = 1.79, 95% confidence interval [CI] = 0.98 to 3.26, P = 0.057. Likewise, meta-analysis revealed no significant difference in LDL-C concentrations between the case and control groups (pooled OR = 1.15, 95% CI = 0.64 to 2.07, P = 0.639. Since there were an insufficient number of studies reporting data for the secondary outcomes, meta-analysis was not possible.Our results do not provide evidence for serum lipids being associated with SSNHL, nor do they definitively rule out such an association. Additional studies are needed to ascertain the relationship, or lack

A meta-analysis of the impacts of genetically modified crops.

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Wilhelm Klümper

Full Text Available Despite the rapid adoption of genetically modified (GM crops by farmers in many countries, controversies about this technology continue. Uncertainty about GM crop impacts is one reason for widespread public suspicion.We carry out a meta-analysis of the agronomic and economic impacts of GM crops to consolidate the evidence.Original studies for inclusion were identified through keyword searches in ISI Web of Knowledge, Google Scholar, EconLit, and AgEcon Search.Studies were included when they build on primary data from farm surveys or field trials anywhere in the world, and when they report impacts of GM soybean, maize, or cotton on crop yields, pesticide use, and/or farmer profits. In total, 147 original studies were included.Analysis of mean impacts and meta-regressions to examine factors that influence outcomes.On average, GM technology adoption has reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%. Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops. Yield and profit gains are higher in developing countries than in developed countries.Several of the original studies did not report sample sizes and measures of variance.The meta-analysis reveals robust evidence of GM crop benefits for farmers in developed and developing countries. Such evidence may help to gradually increase public trust in this technology.

Diagnostic significance of microRNAs as novel biomarkers for bladder cancer: a meta-analysis of ten articles.

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Shi, Hong-Bin; Yu, Jia-Xing; Yu, Jian-Xiu; Feng, Zheng; Zhang, Chao; Li, Guang-Yong; Zhao, Rui-Ning; Yang, Xiao-Bo

2017-08-03

Previous studies have revealed the importance of microRNAs' (miRNAs) function as biomarkers in diagnosing human bladder cancer (BC). However, the results are discordant. Consequently, the possibility of miRNAs to be BC biomarkers was summarized in this meta-analysis. In this study, the relevant articles were systematically searched from CBM, PubMed, EMBASE, and Chinese National Knowledge Infrastructure (CNKI). The bivariate model was used to calculate the pooled diagnostic parameters and summary receiver operator characteristic (SROC) curve in this meta-analysis, thereby estimating the whole predictive performance. STATA software was used during the whole analysis. Thirty-one studies from 10 articles, including 1556 cases and 1347 controls, were explored in this meta-analysis. In short, the pooled sensitivity, area under the SROC curve, specificity, positive likelihood ratio, diagnostic odds ratio, and negative likelihood ratio were 0.72 (95%CI 0.66-0.76), 0.80 (0.77-0.84), 0.76 (0.71-0.81), 3.0 (2.4-3.8), 8 (5.0-12.0), and 0.37 (0.30-0.46) respectively. Additionally, sub-group and meta-regression analyses revealed that there were significant differences between ethnicity, miRNA profiling, and specimen sub-groups. These results suggested that Asian population-based studies, multiple-miRNA profiling, and blood-based assays might yield a higher diagnostic accuracy than their counterparts. This meta-analysis demonstrated that miRNAs, particularly multiple miRNAs in the blood, might be novel, useful biomarkers with relatively high sensitivity and specificity and can be used for the diagnosis of BC. However, further prospective studies with more samples should be performed for further validation.

Automatic imitation: A meta-analysis.

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Cracco, Emiel; Bardi, Lara; Desmet, Charlotte; Genschow, Oliver; Rigoni, Davide; De Coster, Lize; Radkova, Ina; Deschrijver, Eliane; Brass, Marcel

2018-05-01

Automatic imitation is the finding that movement execution is facilitated by compatible and impeded by incompatible observed movements. In the past 15 years, automatic imitation has been studied to understand the relation between perception and action in social interaction. Although research on this topic started in cognitive science, interest quickly spread to related disciplines such as social psychology, clinical psychology, and neuroscience. However, important theoretical questions have remained unanswered. Therefore, in the present meta-analysis, we evaluated seven key questions on automatic imitation. The results, based on 161 studies containing 226 experiments, revealed an overall effect size of g z = 0.95, 95% CI [0.88, 1.02]. Moderator analyses identified automatic imitation as a flexible, largely automatic process that is driven by movement and effector compatibility, but is also influenced by spatial compatibility. Automatic imitation was found to be stronger for forced choice tasks than for simple response tasks, for human agents than for nonhuman agents, and for goalless actions than for goal-directed actions. However, it was not modulated by more subtle factors such as animacy beliefs, motion profiles, or visual perspective. Finally, there was no evidence for a relation between automatic imitation and either empathy or autism. Among other things, these findings point toward actor-imitator similarity as a crucial modulator of automatic imitation and challenge the view that imitative tendencies are an indicator of social functioning. The current meta-analysis has important theoretical implications and sheds light on longstanding controversies in the literature on automatic imitation and related domains. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

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

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

2018-03-01

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

Meta-analysis in microbiology

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N Pabalan

2014-01-01

Full Text Available The use of meta-analysis in microbiology may facilitate decision-making that impacts public health policy. Directed at clinicians and researchers in microbiology, this review outlines the steps in performing this statistical technique, addresses its biases and describes its value in this discipline. The survey to estimate extent of the use of meta-analyses in microbiology shows the remarkable growth in the use of this research methodology, from a minimal Asian output to a level comparable with those of Europe and North America in the last 7 years.

The effectiveness of oral appliances for obstructive sleep apnea syndrome: A meta-analysis.

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Zhu, Yafen; Long, Hu; Jian, Fan; Lin, Jianchang; Zhu, Jingyi; Gao, Meiya; Lai, Wenli

2015-12-01

To evaluate the effectiveness of oral appliances (OAs) for managing patients with obstructive sleep apnea (OSA). PubMed, Embase, Web of Science, CENTRAL and SIGLE were electronically searched from January 1980 to September 2015 for randomized or nonrandomized controlled trials that assessed the effectiveness of OAs on OSAS. The processes of study search, selection, data extraction, assessment of risk of bias and evaluation of evidence quality were conducted independently by two reviewer authors. Meta-analyses were performed in Review Manager 5, Stata11.0 and StatsDirect 2.7.9. Finally, we included 17 eligible studies which compared OAs and placebo or blank control. Six outcomes were assessed in this meta-analysis, i.e., apnea hypopnea index (AHI), respiratory arousal index (RAI), minimum oxygen saturation(MinSaO2), rapid eye movement (REM) sleep, sleep efficiency and Epworth Sleepiness Scale (ESS). Meta-analysis revealed that the pooled mean differences were -10.26 [95% CI: (-12.59, -7.93)], -9.03 [95% CI: (-11.89, -6.17)], 3.08 [95% CI: (1.97, 4.19)], 0.36 [95% CI: (-0.30, 1.02)], 1.34 [95% CI: (-0.05, 2.73)] and -1.76 [95% CI: (-2.57, -0.94)], respectively. The sensitivity analysis and subgroup analysis displayed generally robust results except for MinSaO2, REM sleep and sleep efficiency. Furthermore, publication bias was detected in RAI and MinSaO2. The available evidence indicates benefits in respiration and sleep quality with oral appliances as compared to placebo devices or blank control, while we cannot determine its effectiveness in sleep efficiency and sleep architecture alterations. However, due to low evidence quality as revealed by GRADE, this finding should be interpreted with caution. Through critical meta-analyses, we found that oral appliances are effective in respiration improving and sleep quality. The existing evidence supports the employment of OAs as a recommendable treatment option for OSA. This meta-analysis helps to direct clinical practice

Circulating Resistin Levels and Risk of Colorectal Cancer: A Meta-Analysis

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Gui Yang

2016-01-01

Full Text Available Objectives. Published data on resistin levels in patients with colorectal cancer (CRC were conflicting and heterogeneous. We conducted a meta-analysis of observational studies to examine the association of circulating resistin levels with carcinogenesis of the CRC. Methods. Potentially eligible studies published up to November 2015 were searched through MEDLINE, EMBASE, Science Citation Index Expanded database, CNKI, and WanFang database. The pooled weighted mean differences (WMDs with 95% confidence intervals (CIs calculated by fixed- or random-effect model were used to estimate the effects. Results. A total of 11 studies involving 965 patients were admitted in our meta-analysis. The pooled effects indicated that resistin levels were higher in CRC patients compared to healthy controls (WMD: 1.47 ng/mL; 95% CI: 0.78 to 2.16, with significant heterogeneity across the studies (I2=72%, p<0.0001. Subgroup analyses and sensitivity analyses revealed that study quality, design, sample type, and resistin assays may account for this heterogeneity. No publication bias was observed. Conclusions. Our meta-analysis suggests that increased circulating resistin levels are associated with greater risk of colorectal cancer. Given the limited number of available studies and significant heterogeneity, larger well-designed randomized studies are warranted.

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

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

2017-01-01

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

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

International Nuclear Information System (INIS)

Koetse, M.J.

2006-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Koetse, M.J.

2006-03-14

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

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

Directory of Open Access Journals (Sweden)

Josephine LL Chong

2017-03-01

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

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

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

2018-03-28

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

Moral development and recidivism: a meta-analysis.

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

2011-12-01

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

Depression as a risk factor for the onset of type 2 diabetes mellitus. A meta-analysis

DEFF Research Database (Denmark)

Knol, M J; Twisk, Jos W R; Beekman, Aartjan T F

2006-01-01

the latter association by reviewing the literature and conducting a meta-analysis of longitudinal studies on this topic. METHODS: Medline and PsycInfo were searched for articles published up to January 2005. All studies that examined the relationship between depression and the onset of type 2 diabetes were...... included. Pooled relative risks were calculated using fixed and random effects models. To explore sources of heterogeneity between studies, subgroup analyses and meta-regression analyses were performed. RESULTS: Nine studies met our inclusion criteria for this meta-analysis. The pooled relative risk was 1......AIMS/HYPOTHESIS: Evidence strongly suggests that depression and type 2 diabetes are associated, but the direction of the association is still unclear. Depression may occur as a consequence of having diabetes, but may also be a risk factor for the onset of type 2 diabetes. This study examined...

Drivers of Wetland Conversion: a Global Meta-Analysis

NARCIS (Netherlands)

van Asselen, S.; Verburg, P.H.; Vermaat, J.E.; Janse, J.

2013-01-01

Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis

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

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Chun, JongSerl; Shim, HaiSun; Kim, Soyoun

2017-04-01

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

Consequences of bullying victimization in childhood and adolescence: A systematic review and meta-analysis

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Moore, Sophie E; Norman, Rosana E; Suetani, Shuichi; Thomas, Hannah J; Sly, Peter D; Scott, James G

2017-01-01

AIM To identify health and psychosocial problems associated with bullying victimization and conduct a meta-analysis summarizing the causal evidence. METHODS A systematic review was conducted using PubMed, EMBASE, ERIC and PsycINFO electronic databases up to 28 February 2015. The study included published longitudinal and cross-sectional articles that examined health and psychosocial consequences of bullying victimization. All meta-analyses were based on quality-effects models. Evidence for causality was assessed using Bradford Hill criteria and the grading system developed by the World Cancer Research Fund. RESULTS Out of 317 articles assessed for eligibility, 165 satisfied the predetermined inclusion criteria for meta-analysis. Statistically significant associations were observed between bullying victimization and a wide range of adverse health and psychosocial problems. The evidence was strongest for causal associations between bullying victimization and mental health problems such as depression, anxiety, poor general health and suicidal ideation and behaviours. Probable causal associations existed between bullying victimization and tobacco and illicit drug use. CONCLUSION Strong evidence exists for a causal relationship between bullying victimization, mental health problems and substance use. Evidence also exists for associations between bullying victimization and other adverse health and psychosocial problems, however, there is insufficient evidence to conclude causality. The strong evidence that bullying victimization is causative of mental illness highlights the need for schools to implement effective interventions to address bullying behaviours. PMID:28401049

Meta-Analysis for Primary and Secondary Data Analysis: The Super-Experiment Metaphor.

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Jackson, Sally

1991-01-01

Considers the relation between meta-analysis statistics and analysis of variance statistics. Discusses advantages and disadvantages as a primary data analysis tool. Argues that the two approaches are partial paraphrases of one another. Advocates an integrative approach that introduces the best of meta-analytic thinking into primary analysis…

Meta-analysis reveals a lack of sexual dimorphism in human amygdala volume.

Science.gov (United States)

Marwha, Dhruv; Halari, Meha; Eliot, Lise

2017-02-15

The amygdala plays a key role in many affective behaviors and psychiatric disorders that differ between men and women. To test whether human amygdala volume (AV) differs reliably between the sexes, we performed a systematic review and meta-analysis of AVs reported in MRI studies of age-matched healthy male and female groups. Using four search strategies, we identified 46 total studies (58 matched samples) from which we extracted effect sizes for the sex difference in AV. All data were converted to Hedges g values and pooled effect sizes were calculated using a random-effects model. Each dataset was further meta-regressed against study year and average participant age. We found that uncorrected amygdala volume is about 10% larger in males, with pooled sex difference effect sizes of g=0.581 for right amygdala (κ=28, n=2022), 0.666 for left amygdala (κ=28, n=2006), and 0.876 for bilateral amygdala (κ=16, n=1585) volumes (all p values brain volume (TBV; g=1.278, pbrain size in males. Among studies reporting AVs normalized for ICV or TBV, sex difference effect sizes were small and not statistically significant: g=0.171 for the right amygdala (p=0.206, κ=13, n=1560); 0.233 for the left amygdala (p=0.092, κ=12, n=1512); and 0.257 for bilateral volume (p=0.131, κ=5, n=1629). These values correspond to less than 0.1% larger corrected right AV and 2.5% larger corrected left AV in males compared to females. In summary, AV is not selectively enhanced in human males, as often claimed. Although we cannot rule out subtle male-female group differences, it is not accurate to refer to the human amygdala as "sexually dimorphic." Copyright © 2016 Elsevier Inc. All rights reserved.

Associations between maternal and paternal parenting behaviors, anxiety and its precursors in early childhood: A meta-analysis.

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Möller, Eline L; Nikolić, Milica; Majdandžić, Mirjana; Bögels, Susan M

2016-04-01

In this meta-analysis we investigated differential associations between maternal and paternal parenting behaviors (overcontrol, overprotection, overinvolvement, autonomy granting, challenging parenting) and anxiety and its precursors (fearful temperament, behavioral inhibition, shyness) in children (0-5years). Two meta-analyses were conducted, one for mothers (k=28, N=5,728), and one for fathers (k=12, N=1,019). In general, associations between parenting and child anxiety were small. Associations between child anxiety and overcontrol, overprotection, and overinvolvement did not differ for mothers and fathers. Maternal autonomy granting was not significantly related to child anxiety, and no studies examined fathers' autonomy granting. A significant difference was found for challenging parenting; mothers' challenging parenting was not significantly related to child anxiety, whereas fathers' challenging parenting was related to less child anxiety. Post-hoc meta-analyses revealed that mothers' and fathers' parenting was more strongly related to children's anxiety symptoms than to child anxiety precursors. Moreover, the association between parenting and child anxiety symptoms was stronger for fathers than for mothers. In conclusion, although parenting plays only a small role in early childhood anxiety, fathers' parenting is at least as important as mothers'. Paternal challenging behavior even seems more important than maternal challenging behavior. Research is needed to determine whether challenging fathering can prevent child anxiety development. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Economic Value of Mangroves: A Meta-Analysis

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Marwa Salem; D. Evan Mercer

2012-01-01

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

Oral versus intravenous methylprednisolone for the treatment of multiple sclerosis relapses: A meta-analysis of randomized controlled trials.

Directory of Open Access Journals (Sweden)

Shuo Liu

Full Text Available Intravenous glucocorticoids are recommended for multiple sclerosis (MS. However, they can be inconvenient and expensive. Due to their convenience and low cost, oral glucocorticoids may be an alternative treatment. Recently, several studies have shown that there is no difference in efficacy and safety between oral methylprednisolone (oMP and intravenous methylprednisolone (ivMP.We sought to assess the clinical efficacy, safety and tolerability of oral methylprednisolone versus intravenous methylprednisolone for MS relapses in this meta-analysis.Randomized controlled trials (RCTs evaluating the clinical efficacy, safety and tolerability of oral methylprednisolone versus intravenous methylprednisolone for MS relapses were searched in PubMed, Cochrane Library, Medline, EMBASE and China Biology Medicine until October 25, 2016, without language restrictions. The proportion of patients who had improved by day 28 was chosen as the efficacy outcome. We chose the risk ratio (RR to analyze each trial with the 95% confidence interval (95% CI. We also used the fixed-effects model (Mantel-Haenszel approach to calculate the pooled relative effect estimates.A total of 5 trials were identified, which included 369 patients. The results of our meta-analysis revealed that no significant difference existed in relapse improvement at day 28 between oMP and ivMP (RR 0.96, 95% CI 0.84 to 1.10. No evidence of heterogeneity existed among the trials (P = 0.45, I2 = 0%. Both treatments were equally safe and well tolerated except that insomnia was more likely to occur in the oMP group compared to the ivMP group.Our meta-analysis reveals strong evidence that oMP is not inferior to ivMP in increasing the proportion of patients experiencing clinical improvement at day 28. In addition, both routes of administration are equally well tolerated and safe. These findings suggest that we may be able to replace ivMP with oMP to treat MS relapses.

Voxelwise meta-analysis of gray matter abnormalities in dementia with Lewy bodies

International Nuclear Information System (INIS)

Zhong, JianGuo; Pan, PingLei; Dai, ZhenYu; Shi, HaiCun

2014-01-01

Highlights: • We first report the meta-analyses of GM anomalies by VBM studies in DLB. • Lateral temporal/insular and lenticular nucleus/insular cortex atrophy were detected. • A characteristic pattern of GM changes underpinned DLB. - Abstract: Background: Increasing neuroimaging studies have revealed brain gray matter (GM) atrophy by voxel-based morphometry (VBM) studies in patients with dementia with Lewy bodies (DLB) relative to healthy controls. However, the spatial localization of GM abnormalities reported in the existing studies is heterogeneous. Here, we aimed to investigate concurrence across VBM studies to help clarify the structural abnormalities underpinning this condition. Methods: A systematic search for VBM studies of DLB patients and healthy controls published in PubMed database from January 2000 to March 2014 was conducted. A quantitative meta-analysis of whole-brain VBM studies in DLB patients and healthy controls was performed by means of Anisotropic Effect Size version of Signed Differential Mapping (AES-SDM) software package. Results: Seven studies comprising 218 DLB patients and 219 healthy controls were included in the present study. Compared to healthy subjects, the patients group showed consistent decreased GM in right lateral temporal/insular cortex and left lenticular nucleus/insular cortex. The results remained largely unchanged in the following jackknife sensitivity analyses. Meta-regression analysis indicated an increased probability of finding brain atrophy in left superior temporal gyrus in patients with lower MMSE scores. Conclusions: The present meta-analysis quantitatively demonstrates a characteristic pattern of GM alternations that contributed to the understanding of pathophysiology underlying DLB. Future studies will benefit from employing meta-analytical comparisons to other dementia subtypes with solid evidence to extend these findings.

Voxelwise meta-analysis of gray matter abnormalities in dementia with Lewy bodies

Energy Technology Data Exchange (ETDEWEB)

Zhong, JianGuo; Pan, PingLei [Department of Neurology, Affiliated Yancheng Hospital of Southeast University, Yancheng (China); Dai, ZhenYu [Department of Radiology, Affiliated Yancheng Hospital of Southeast University, Yancheng (China); Shi, HaiCun, E-mail: yc3yhcshi@gmail.com [Department of Neurology, Affiliated Yancheng Hospital of Southeast University, Yancheng (China)

2014-10-15

Highlights: • We first report the meta-analyses of GM anomalies by VBM studies in DLB. • Lateral temporal/insular and lenticular nucleus/insular cortex atrophy were detected. • A characteristic pattern of GM changes underpinned DLB. - Abstract: Background: Increasing neuroimaging studies have revealed brain gray matter (GM) atrophy by voxel-based morphometry (VBM) studies in patients with dementia with Lewy bodies (DLB) relative to healthy controls. However, the spatial localization of GM abnormalities reported in the existing studies is heterogeneous. Here, we aimed to investigate concurrence across VBM studies to help clarify the structural abnormalities underpinning this condition. Methods: A systematic search for VBM studies of DLB patients and healthy controls published in PubMed database from January 2000 to March 2014 was conducted. A quantitative meta-analysis of whole-brain VBM studies in DLB patients and healthy controls was performed by means of Anisotropic Effect Size version of Signed Differential Mapping (AES-SDM) software package. Results: Seven studies comprising 218 DLB patients and 219 healthy controls were included in the present study. Compared to healthy subjects, the patients group showed consistent decreased GM in right lateral temporal/insular cortex and left lenticular nucleus/insular cortex. The results remained largely unchanged in the following jackknife sensitivity analyses. Meta-regression analysis indicated an increased probability of finding brain atrophy in left superior temporal gyrus in patients with lower MMSE scores. Conclusions: The present meta-analysis quantitatively demonstrates a characteristic pattern of GM alternations that contributed to the understanding of pathophysiology underlying DLB. Future studies will benefit from employing meta-analytical comparisons to other dementia subtypes with solid evidence to extend these findings.

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

Science.gov (United States)

Chen, Qixuan; Li, Jingguang

2014-05-01

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

A meta-analytic review of psychological treatments for tinnitus.

Science.gov (United States)

Andersson, G; Lyttkens, L

1999-08-01

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

Adjunctive Nutraceuticals for Depression: A Systematic Review and Meta-Analyses.

Science.gov (United States)

Sarris, Jerome; Murphy, Jenifer; Mischoulon, David; Papakostas, George I; Fava, Maurizio; Berk, Michael; Ng, Chee H

2016-06-01

There is burgeoning interest in augmentation strategies for improving inadequate response to antidepressants. The adjunctive use of standardized pharmaceutical-grade nutrients, known as nutraceuticals, has the potential to modulate several neurochemical pathways implicated in depression. While many studies have been conducted in this area, to date no specialized systematic review (or meta-analysis) has been conducted. A systematic search of PubMed, CINAHL, Cochrane Library, and Web of Science was conducted up to December 2015 for clinical trials using adjunctive nutrients for depression. Where sufficient data were available, a random-effects model analyzed the standard mean difference between treatment and placebo in the change from baseline to endpoint, combining the effect size data. Funnel plot and heterogeneity analyses were also performed. Primarily positive results were found for replicated studies testing S-adenosylmethionine (SAMe), methylfolate, omega-3 (primarily EPA or ethyl-EPA), and vitamin D, with positive isolated studies for creatine, folinic acid, and an amino acid combination. Mixed results were found for zinc, folic acid, vitamin C, and tryptophan, with nonsignificant results for inositol. No major adverse effects were noted in the studies (aside from minor digestive disturbance). A meta-analysis of adjunctive omega-3 versus placebo revealed a significant and moderate to strong effect in favor of omega-3. Conversely, a meta-analysis of folic acid revealed a nonsignificant difference from placebo. Marked study heterogeneity was found in a Higgins test for both omega-3 and folic acid studies; funnel plots also revealed asymmetry (reflecting potential study bias). Current evidence supports adjunctive use of SAMe, methylfolate, omega-3, and vitamin D with antidepressants to reduce depressive symptoms.

Network meta-analysis-highly attractive but more methodological research is needed

Directory of Open Access Journals (Sweden)

Singh Sonal

2011-06-01

Full Text Available Abstract Network meta-analysis, in the context of a systematic review, is a meta-analysis in which multiple treatments (that is, three or more are being compared using both direct comparisons of interventions within randomized controlled trials and indirect comparisons across trials based on a common comparator. To ensure validity of findings from network meta-analyses, the systematic review must be designed rigorously and conducted carefully. Aspects of designing and conducting a systematic review for network meta-analysis include defining the review question, specifying eligibility criteria, searching for and selecting studies, assessing risk of bias and quality of evidence, conducting a network meta-analysis, interpreting and reporting findings. This commentary summarizes the methodologic challenges and research opportunities for network meta-analysis relevant to each aspect of the systematic review process based on discussions at a network meta-analysis methodology meeting we hosted in May 2010 at the Johns Hopkins Bloomberg School of Public Health. Since this commentary reflects the discussion at that meeting, it is not intended to provide an overview of the field.

Associations between interleukin-1 polymorphisms and susceptibility to vasculitis: a meta-analysis.

Science.gov (United States)

Song, G G; Kim, J-H; Lee, Y H

2016-05-01

The objective of this study was to determine whether interleukin-1 (IL-1) polymorphisms are associated with susceptibility to vasculitis. A meta-analysis was conducted to investigate possible associations between IL-1A, IL-1B, and IL-1 receptor antagonist (IL1RN) polymorphisms and vasculitis. A total of 17 studies involving 1384 vasculitis cases [Behçet's disease (BD), IgA vasculitis, anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), Kawasaki disease (KD), giant cell arteritis, and Takayasu's arteritis] and 2710 controls were included in the meta-analysis. This analysis showed an association between BD and the TT + TC genotypes of the IL-1A-889 C/T polymorphism in the entire study population [odds ratio (OR) = 0.623, 95 % CI = 0.395-0.981, p = 0.045), and a trend toward an association in a Turkish population (OR = 0.578, 95 % CI = 0.331-1.010, p = 0.054). A meta-analysis of the IL1RN polymorphism revealed no association with vasculitis in all study subjects (OR for IL1RN*2 = 0.904, 95 % CI = 0.626-1.304, p = 0.588). However, stratification by ethnicity revealed a significant association between the IL1RN*2 allele and vasculitis including AAV, BD, KD in Asians (OR = 2.393, 95 % CI = 1.429-4.006, p = 0.001), but not in Caucasian and Turkish populations (OR = 0.776, 95 % CI = 0.487-1.238, p = 0.288; OR = 0.914, 95 % CI = 0.667-1.252, p = 0.576, respectively). No association was found between vasculitis and the IL-1B-511 C/T polymorphism, or the IL-1B+3953 C/T polymorphism. This meta-analysis suggests that the IL-1A-889 C/T polymorphism is associated with susceptibility to BD, and that the IL1RN*2 allele is associated with susceptibility to vasculitis including AAV, BD, and KD in Asians.

Occupational and environmental scleroderma. Systematic review and meta-analysis.

Science.gov (United States)

Rubio-Rivas, Manuel; Moreno, Rafael; Corbella, Xavier

2017-03-01

The etiology of systemic sclerosis (SSc) remains unknown; however, several occupational and environmental factors have been implicated. Our objective was to perform a meta-analysis of all studies published on SSc associated with occupational and environmental exposure. The review was undertaken by means of MEDLINE and SCOPUS from 1960 to 2014 and using the terms: "systemic," "scleroderma," or "systemic sclerosis/chemically induced" [MesH]. The Newcastle-Ottawa Scale was used for the qualifying assessment. The inverse variance-weighted method was performed. The meta-analysis of silica exposure included 15 case-control studies [overall OR 2.81 (95%CI 1.86-4.23; p < 0.001)] and 4 cohort studies [overall RR 17.52 (95%CI 5.98-51.37; p < 0.001)]; the meta-analysis of solvents exposure included 13 case-control studies (overall OR 2.00 [95%CI 1.32-3.02; p = 0.001); the meta-analysis of breast implants exposure included 4 case-control studies (overall OR 1.68 (95%CI 1.65-1.71; p < 0.001)) and 6 cohort studies (overall RR 2.13 (95%CI 0.86-5.27; p = 0.10)); the meta-analysis of epoxy resins exposure included 4 case-control studies (overall OR 2.97 (95%CI 2.31-3.83; p < 0.001)), the meta-analysis of pesticides exposure included 3 case-control studies (overall OR 1.02 (95%CI 0.78-1.32; p = 0.90)) and, finally, the meta-analysis of welding fumes exposure included 4 studies (overall OR 1.29 (95%CI 0.44-3.74; p = 0.64)). Not enough studies citing risks related to hair dyes have been published to perform an accurate meta-analysis. Silica and solvents were the two most likely substances related to the pathogenesis of SSc. While silica is involved in particular jobs, solvents are widespread and more people are at risk of having incidental contact with them.

Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

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Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

2016-09-01

Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship.

A novel bi-level meta-analysis approach: applied to biological pathway analysis.

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Nguyen, Tin; Tagett, Rebecca; Donato, Michele; Mitrea, Cristina; Draghici, Sorin

2016-02-01

The accumulation of high-throughput data in public repositories creates a pressing need for integrative analysis of multiple datasets from independent experiments. However, study heterogeneity, study bias, outliers and the lack of power of available methods present real challenge in integrating genomic data. One practical drawback of many P-value-based meta-analysis methods, including Fisher's, Stouffer's, minP and maxP, is that they are sensitive to outliers. Another drawback is that, because they perform just one statistical test for each individual experiment, they may not fully exploit the potentially large number of samples within each study. We propose a novel bi-level meta-analysis approach that employs the additive method and the Central Limit Theorem within each individual experiment and also across multiple experiments. We prove that the bi-level framework is robust against bias, less sensitive to outliers than other methods, and more sensitive to small changes in signal. For comparative analysis, we demonstrate that the intra-experiment analysis has more power than the equivalent statistical test performed on a single large experiment. For pathway analysis, we compare the proposed framework versus classical meta-analysis approaches (Fisher's, Stouffer's and the additive method) as well as against a dedicated pathway meta-analysis package (MetaPath), using 1252 samples from 21 datasets related to three human diseases, acute myeloid leukemia (9 datasets), type II diabetes (5 datasets) and Alzheimer's disease (7 datasets). Our framework outperforms its competitors to correctly identify pathways relevant to the phenotypes. The framework is sufficiently general to be applied to any type of statistical meta-analysis. The R scripts are available on demand from the authors. sorin@wayne.edu Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e

The relationship between nature connectedness and happiness: a meta-analysis

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Colin A. Capaldi

2014-09-01

Full Text Available Research suggests that contact with nature can be beneficial, for example leading to improvements in mood, cognition, and health. A distinct but related idea is the personality construct of subjective nature connectedness, a stable individual difference in cognitive, affective, and experiential connection with the natural environment. Subjective nature connectedness is a strong predictor of pro-environmental attitudes and behaviours that may also be positively associated with subjective well-being. This meta-analysis was conducted to examine the relationship between nature connectedness and happiness. Based on 30 samples (n = 8,523, a fixed-effect meta-analysis found a small but significant effect size (r = .19. Those who are more connected to nature tended to experience more positive affect, vitality, and life satisfaction compared to those less connected to nature. Publication status, year, average age, and percentage of females in the sample were not significant moderators. Vitality had the strongest relationship with nature connectedness (r = .24, followed by positive affect (r = .22 and life satisfaction (r = .17. In terms of specific nature connectedness measures, associations were the strongest between happiness and inclusion of nature in self (r = .27, compared to nature relatedness (r = .18 and connectedness to nature (r = .18. This research highlights the importance of considering personality when examining the psychological benefits of nature. The results suggest that closer human-nature relationships do not have to come at the expense of happiness. Rather, this meta-analysis shows that being connected to nature and feeling happy are, in fact, connected.

Relationship between hypothyroidism and the incidence of gestational diabetes: A meta-analysis.

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Gong, Li-Li; Liu, He; Liu, Li-Hong

2016-04-01

Hypothyroidism disorders and gestational diabetes are among the most common endocrinopathies during pregnancy. We conducted a meta-analysis to investigate whether hypothyroidism in pregnancy is associated with gestational diabetes risk. Published literature from PubMed and EMBASE were searched for eligible publications. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using a fixed- or random-effects model. Seven articles described the relationship between hypothyroidism and risk of gestational diabetes. This meta-analysis revealed that overt hypothyroidism was associated with an increased risk of gestational diabetes (OR 1.892, 95% CI 1.679-2.132, p hypothyroidism, with the OR of 1.558 (95% CI 1.292-1.877, p hypothyroidism was 1.749 (95% CI 1.586-1.928, p hypothyroidism may be a risk factor for gestational diabetes. Copyright © 2016. Published by Elsevier B.V.

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

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Wen, Yun; van Heuven, Walter J B

2017-06-01

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

Mass meta-analysis in Talairach space

DEFF Research Database (Denmark)

Nielsen, Finn Årup

2004-01-01

We provide a method for mass meta-analysis in a neuroinformatics database containing stereotaxic Talairach coordinates from neuroimaging experiments. Database labels are used to group the individual experiments, e.g., according to cognitive function, and the consistent pattern of the experiments...... of experiments, and the distances to the null hypotheses are used to sort the voxels across groups of experiments. This allows for mass meta-analysis, with the construction of a list with the most prominent associations between brain areas and group labels. Furthermore, the method can be used for functional...

Curcuminoids Lower Plasma Leptin Concentrations: A Meta-analysis.

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Atkin, Stephen L; Katsiki, Niki; Derosa, Giuseppe; Maffioli, Pamela; Sahebkar, Amirhossein

2017-12-01

Curcumin is a naturally occurring polyphenol that has been suggested to improve several metabolic diseases. Leptin is an adipokine involved in metabolic status and appetite, with marked crosstalk with other systems. Available data suggest that curcumin may affect leptin levels; therefore, this meta-analysis was performed to evaluate this. A systematic review and meta-analysis were undertaken on all randomized controlled trials of curcumin studies that included the measurement of leptin. The search included PubMed-Medline, Scopus, ISI Web of Knowledge, and Google Scholar databases. Quantitative data synthesis was performed by using a random-effects model, with standardized mean difference and 95% confidence interval as summary statistics. A funnel plot, Begg's rank correlation, and Egger's weighted regression tests assessed the presence of publication bias. Four eligible articles comprising five treatment arms were selected for the meta-analysis. Meta-analysis showed a significant decrease in plasma leptin concentrations following curcumin treatment (standardized mean difference: -0.69, 95% confidence interval: -1.16, -0.23, p = 0.003; I 2  = 76.53%). There was no evidence of publication bias. This meta-analysis showed that curcumin supplementation is associated with a decrease in leptin levels that may be regarded as a potential mechanism for the metabolic effects of curcumin. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Systematic review and meta-analysis of Saccharomyces boulardii in adult patients.

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McFarland, Lynne V

2010-05-14

This article reviews the evidence for efficacy and safety of Saccharomyces boulardii (S. boulardii) for various disease indications in adults based on the peer-reviewed, randomized clinical trials and pre-clinical studies from the published medical literature (Medline, Clinical Trial websites and meeting abstracts) between 1976 and 2009. For meta-analysis, only randomized, blinded controlled trials unrestricted by language were included. Pre-clinical studies, volunteer studies and uncontrolled studies were excluded from the review of efficacy and meta-analysis, but included in the systematic review. Of 31 randomized, placebo-controlled treatment arms in 27 trials (encompassing 5029 study patients), S. boulardii was found to be significantly efficacious and safe in 84% of those treatment arms. A meta-analysis found a significant therapeutic efficacy for S. boulardii in the prevention of antibiotic-associated diarrhea (AAD) (RR = 0.47, 95% CI: 0.35-0.63, P boulardii can be strongly recommended for the prevention of AAD and the traveler's diarrhea. Randomized trials also support the use of this yeast probiotic for prevention of enteral nutrition-related diarrhea and reduction of Helicobacter pylori treatment-related symptoms. S. boulardii shows promise for the prevention of C. difficile disease recurrences; treatment of irritable bowel syndrome, acute adult diarrhea, Crohn's disease, giardiasis, human immunodeficiency virus-related diarrhea; but more supporting evidence is recommended for these indications. The use of S. boulardii as a therapeutic probiotic is evidence-based for both efficacy and safety for several types of diarrhea.

Bivariate genome-wide association meta-analysis of pediatric musculoskeletal traits reveals pleiotropic effects at the SREBF1/TOM1L2 locus

DEFF Research Database (Denmark)

Medina-Gomez, Carolina; Kemp, John P; Dimou, Niki L

2017-01-01

Bone mineral density is known to be a heritable, polygenic trait whereas genetic variants contributing to lean mass variation remain largely unknown. We estimated the shared SNP heritability and performed a bivariate GWAS meta-analysis of total-body lean mass (TB-LM) and total-body less head bone...... as in human muscle tissue. This is the first bivariate GWAS meta-analysis to demonstrate genetic factors with pleiotropic effects on bone mineral density and lean mass.Bone mineral density and lean skeletal mass are heritable traits. Here, Medina-Gomez and colleagues perform bivariate GWAS analyses of total...

Meta-analysis of grain yield QTL identified during agricultural drought in grasses showed consensus.

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Swamy, B P Mallikarjuna; Vikram, Prashant; Dixit, Shalabh; Ahmed, H U; Kumar, Arvind

2011-06-16

In the last few years, efforts have been made to identify large effect QTL for grain yield under drought in rice. However, identification of most precise and consistent QTL across the environments and genetics backgrounds is essential for their successful use in Marker-assisted Selection. In this study, an attempt was made to locate consistent QTL regions associated with yield increase under drought by applying a genome-wide QTL meta-analysis approach. The integration of 15 maps resulted in a consensus map with 531 markers and a total map length of 1821 cM. Fifty-three yield QTL reported in 15 studies were projected on a consensus map and meta-analysis was performed. Fourteen meta-QTL were obtained on seven chromosomes. MQTL1.2, MQTL1.3, MQTL1.4, and MQTL12.1 were around 700 kb and corresponded to a reasonably small genetic distance of 1.8 to 5 cM and they are suitable for use in marker-assisted selection (MAS). The meta-QTL for grain yield under drought coincided with at least one of the meta-QTL identified for root and leaf morphology traits under drought in earlier reports. Validation of major-effect QTL on a panel of random drought-tolerant lines revealed the presence of at least one major QTL in each line. DTY12.1 was present in 85% of the lines, followed by DTY4.1 in 79% and DTY1.1 in 64% of the lines. Comparative genomics of meta-QTL with other cereals revealed that the homologous regions of MQTL1.4 and MQTL3.2 had QTL for grain yield under drought in maize, wheat, and barley respectively. The genes in the meta-QTL regions were analyzed by a comparative genomics approach and candidate genes were deduced for grain yield under drought. Three groups of genes such as stress-inducible genes, growth and development-related genes, and sugar transport-related genes were found in clusters in most of the meta-QTL. Meta-QTL with small genetic and physical intervals could be useful in Marker-assisted selection individually and in combinations. Validation and comparative

Natural funnel asymmetries. A simulation analysis of the three basic tools of meta analysis

DEFF Research Database (Denmark)

Callot, Laurent Abdelkader Francois; Paldam, Martin

Meta-analysis studies a set of estimates of one parameter with three basic tools: The funnel diagram is the distribution of the estimates as a function of their precision; the funnel asymmetry test, FAT; and the meta average, where PET is an estimate. The FAT-PET MRA is a meta regression analysis...

Comparing Active Pediatric Obesity Treatments Using Meta-Analysis

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

2008-01-01

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

Comparative linkage meta-analysis reveals regionally-distinct, disparate genetic architectures: application to bipolar disorder and schizophrenia.

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Brady Tang

2011-04-01

Full Text Available New high-throughput, population-based methods and next-generation sequencing capabilities hold great promise in the quest for common and rare variant discovery and in the search for "missing heritability." However, the optimal analytic strategies for approaching such data are still actively debated, representing the latest rate-limiting step in genetic progress. Since it is likely a majority of common variants of modest effect have been identified through the application of tagSNP-based microarray platforms (i.e., GWAS, alternative approaches robust to detection of low-frequency (1-5% MAF and rare (<1% variants are of great importance. Of direct relevance, we have available an accumulated wealth of linkage data collected through traditional genetic methods over several decades, the full value of which has not been exhausted. To that end, we compare results from two different linkage meta-analysis methods--GSMA and MSP--applied to the same set of 13 bipolar disorder and 16 schizophrenia GWLS datasets. Interestingly, we find that the two methods implicate distinct, largely non-overlapping, genomic regions. Furthermore, based on the statistical methods themselves and our contextualization of these results within the larger genetic literatures, our findings suggest, for each disorder, distinct genetic architectures may reside within disparate genomic regions. Thus, comparative linkage meta-analysis (CLMA may be used to optimize low-frequency and rare variant discovery in the modern genomic era.

Periodontal disease and risk of chronic obstructive pulmonary disease: a meta-analysis of observational studies.

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Xian-Tao Zeng

Full Text Available BACKGROUND: Many epidemiological studies have found a positive association between periodontal disease (PD and risk of chronic obstructive pulmonary disease (COPD, but this association is varied and even contradictory among studies. We performed a meta-analysis to ascertain the relationship between PD and COPD. METHODS: PubMed and Embase database were searched up to January 10, 2012, for relevant observational studies on the association between PD and risk of COPD. Data from the studies selected were extracted and analyzed independently by two authors. The meta-analysis was performed using the Comprehensive Meta-Analysis software. RESULTS: Fourteen observational studies (one nested case-control, eight case-control, and five cross-sectional involving 3,988 COPD patients were yielded. Based on random-effects meta-analysis, a significant association between PD and COPD was identified (odds ratio = 2.08, 95% confidence interval = 1.48-2.91; P<0.001, with sensitivity analysis showing that the result was robust. Subgroups analyses according to study design, ethnicity, assessment of PD/COPD, and adjusted/unadjusted odds ratios also revealed a significant association. Publication bias was detected. CONCLUSIONS: Based on current evidence, PD is a significant and independent risk factor of COPD. However, whether a causal relationships exists remains unclear. Morever, we suggest performing randomized controlled trails to explore whether periodontal interventions are beneficial in regulating COPD pathogenesis and progression.

Meta-analysis for evidence synthesis in plant pathology: an overview.

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Madden, L V; Paul, P A

2011-01-01

Meta-analysis is the analysis of the results of multiple studies, which is typically performed in order to synthesize evidence from many possible sources in a formal probabilistic manner. In a simple sense, the outcome of each study becomes a single observation in the meta-analysis of all available studies. The methodology was developed originally in the social sciences by Smith, Glass, Rosenthal, Hunter, and Schmidt, based on earlier pioneering contributions in statistics by Fisher, Pearson, Yates, and Cochran, but this approach to research synthesis has now been embraced within many scientific disciplines. However, only a handful of articles have been published in plant pathology and related fields utilizing meta-analysis. After reviewing basic concepts and approaches, methods for estimating parameters and interpreting results are shown. The advantages of meta-analysis are presented in terms of prediction and risk analysis, and the high statistical power that can be achieved for detecting significant effects of treatments or significant relationships between variables. Based on power considerations, the fallacy of naïve counting of P values in a narrative review is demonstrated. Although there are many advantages to meta-analysis, results can be biased if the analysis is based on a nonrepresentative sample of study outcomes. Therefore, novel approaches for characterizing the upper bound on the bias are discussed, in order to show the robustness of meta-analysis to possible violation of assumptions.

Sex differences in emotional perception: Meta analysis of divergent activation.

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Filkowski, Megan M; Olsen, Rachel M; Duda, Bryant; Wanger, Timothy J; Sabatinelli, Dean

2017-02-15

Behavioral and physiological sex differences in emotional reactivity are well documented, yet comparatively few neural differences have been identified. Here we apply quantitative activation likelihood estimation (ALE) meta-analysis across functional brain imaging studies that each reported clusters of activity differentiating men and women as they participated in emotion-evoking tasks in the visual modality. This approach requires the experimental paradigm to be balanced across the sexes, and thus may provide greater clarity than previous efforts. Results across 56 emotion-eliciting studies (n=1907) reveal distinct activation in the medial prefrontal cortex, anterior cingulate cortex, frontal pole, and mediodorsal nucleus of the thalamus in men relative to women. Women show distinct activation in bilateral amygdala, hippocampus, and regions of the dorsal midbrain including the periaqueductal gray/superior colliculus and locus coeruleus. While some clusters are consistent with prevailing perspectives on the foundations of sex differences in emotional reactivity, thalamic and brainstem regions have not previously been highlighted as sexually divergent. These data strongly support the need to include sex as a factor in functional brain imaging studies of emotion, and to extend our investigative focus beyond the cortex. Copyright © 2016 Elsevier Inc. All rights reserved.

Meta-analysis of melanin-concentrating hormone signaling-deficient mice on behavioral and metabolic phenotypes.

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Kenkichi Takase

Full Text Available The demand for meta-analyses in basic biomedical research has been increasing because the phenotyping of genetically modified mice does not always produce consistent results. Melanin-concentrating hormone (MCH has been reported to be involved in a variety of behaviors that include feeding, body-weight regulation, anxiety, sleep, and reward behavior. However, the reported behavioral and metabolic characteristics of MCH signaling-deficient mice, such as MCH-deficient mice and MCH receptor 1 (MCHR1-deficient mice, are not consistent with each other. In the present study, we performed a meta-analysis of the published data related to MCH-deficient and MCHR1-deficient mice to obtain robust conclusions about the role of MCH signaling. Overall, the meta-analysis revealed that the deletion of MCH signaling enhanced wakefulness, locomotor activity, aggression, and male sexual behavior and that MCH signaling deficiency suppressed non-REM sleep, anxiety, responses to novelty, startle responses, and conditioned place preferences. In contrast to the acute orexigenic effect of MCH, MCH signaling deficiency significantly increased food intake. Overall, the meta-analysis also revealed that the deletion of MCH signaling suppressed the body weight, fat mass, and plasma leptin, while MCH signaling deficiency increased the body temperature, oxygen consumption, heart rate, and mean arterial pressure. The lean phenotype of the MCH signaling-deficient mice was also confirmed in separate meta-analyses that were specific to sex and background strain (i.e., C57BL/6 and 129Sv. MCH signaling deficiency caused a weak anxiolytic effect as assessed with the elevated plus maze and the open field test but also caused a weak anxiogenic effect as assessed with the emergence test. MCH signaling-deficient mice also exhibited increased plasma corticosterone under non-stressed conditions, which suggests enhanced activity of the hypothalamic-pituitary-adrenal axis. To the best of our

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

Science.gov (United States)

Verdú, Miguel; Traveset, Anna

2004-02-01

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

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

NARCIS (Netherlands)

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

2008-01-01

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

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

NARCIS (Netherlands)

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

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

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

NARCIS (Netherlands)

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

2008-01-01

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

Systematic review with meta-analysis

DEFF Research Database (Denmark)

Kimer, N; Krag, A; Møller, Søren

2014-01-01

BACKGROUND: Rifaximin is recommended for prevention of hepatic encephalopathy (HE). The effects of rifaximin on overt and minimal HE are debated. AIM: To perform a systematic review and meta-analysis of randomised controlled trials (RCTs) on rifaximin for HE. METHODS: We performed electronic...... and manual searches, gathered information from the U.S. Food and Drug Administration Home Page, and obtained unpublished information on trial design and outcome measures from authors and pharmaceutical companies. Meta-analyses were performed and results presented as risk ratios (RR) with 95% confidence...

Systematic review with meta-analysis

DEFF Research Database (Denmark)

Roda, G; Narula, N; Pinotti, R

2017-01-01

and meta-analysis of epidemiological studies reporting on extension of ulcerative colitis to determine frequency of disease extension in patients with limited ulcerative colitis at diagnosis. METHODS: We performed a systematic literature search to identify studies on disease extension of ulcerative colitis...... (UC) and predictors of disease progression. RESULTS: Overall, 41 studies were eligible for systematic review but only 30 for meta-analysis. The overall pooled frequency of UC extension was 22.8% with colonic extension being 17.8% at 5 years and 31% at 10 years. Extension was 17.8% (95% CI 11...... in patients from North America (37.8%) than from Europe (19.6%) (Pmeta-analysis, approximately one quarter of patients with limited UC extend over time with most extension occurring during the first 10 years. Rate of extension depends on age at diagnosis and geographic origin...

Large-Scale Cognitive GWAS Meta-Analysis Reveals Tissue-Specific Neural Expression and Potential Nootropic Drug Targets

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Max Lam

2017-11-01

Full Text Available Here, we present a large (n = 107,207 genome-wide association study (GWAS of general cognitive ability (“g”, further enhanced by combining results with a large-scale GWAS of educational attainment. We identified 70 independent genomic loci associated with general cognitive ability. Results showed significant enrichment for genes causing Mendelian disorders with an intellectual disability phenotype. Competitive pathway analysis implicated the biological processes of neurogenesis and synaptic regulation, as well as the gene targets of two pharmacologic agents: cinnarizine, a T-type calcium channel blocker, and LY97241, a potassium channel inhibitor. Transcriptome-wide and epigenome-wide analysis revealed that the implicated loci were enriched for genes expressed across all brain regions (most strongly in the cerebellum. Enrichment was exclusive to genes expressed in neurons but not oligodendrocytes or astrocytes. Finally, we report genetic correlations between cognitive ability and disparate phenotypes including psychiatric disorders, several autoimmune disorders, longevity, and maternal age at first birth.

Educational intervention on physical restraint use in long-term care facilities – Systematic review and meta-analysis

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Shao-Huan Lan

2017-08-01

Full Text Available “Physical restraint” formerly used as a measure of protection for psychiatric patients is now widely used. However, existing studies showed that physical restraint not only has inadequate effect of protection but also has negative effects on residents. To analyzes the impact of educational program on the physical restraint use in long-term care facilities. Design: A systematic review with meta-analysis and meta-regression. Eight databases, including Cochrane Library, ProQuest, PubMed, EMBASE, EBSCO, Web of Science, Ovid Medline and Physiotherapy Evidence Database (PEDro, were searched up to January 2017. Eligible studies were classified by intervention and accessed for quality using the Quality Assessment Tool for quantitative studies. Sixteen research articles were eligible in the final review; 10 randomize control trail studies were included in the analysis. The meta-analysis revealed that the use of physical restraint was significantly less often in the experimental (education group (OR = 0.55, 95% CI: 0.39 to 0.78, p < 0.001 compared to the control group. Meta-regression revealed the period of post education would have decreased the effect of the restraint educational program (β: 0.08, p = 0.002; instead, the longer education period and more times of education would have a stronger effect of reducing the use of physical restraint (β: −0.07, p < 0.001; β: −0.04, p = 0.056. The educational program had an effect on the reduced use of physical restraint. The results of meta-regression suggest that long-term care facilities should provide a continuous education program of physical restraint for caregivers.

A meta-analysis of math performance in Turner syndrome.

Science.gov (United States)

Baker, Joseph M; Reiss, Allan L

2016-02-01

Studies investigating the relationship between Turner syndrome and math learning disability have used a wide variation of tasks designed to test various aspects of mathematical competencies. Although these studies have revealed much about the math deficits common to Turner syndrome, their diversity makes comparisons between individual studies difficult. As a result, the consistency of outcomes among these diverse measures remains unknown. The overarching aim of this review is to provide a systematic meta-analysis of the differences in math and number performance between females with Turner syndrome and age-matched neurotypical peers. We provide a meta-analysis of behavioral performance in Turner syndrome relative to age-matched neurotypical populations on assessments of math and number aptitude. In total, 112 comparisons collected across 17 studies were included. Although 54% of all statistical comparisons in our analyses failed to reject the null hypothesis, our results indicate that meaningful group differences exist on all comparisons except those that do not require explicit calculation. Taken together, these results help elucidate our current understanding of math and number weaknesses in Turner syndrome, while highlighting specific topics that require further investigation. © 2015 Mac Keith Press.

Association between fat mass- and obesity-associated (FTO gene polymorphism and polycystic ovary syndrome: a meta-analysis.

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Xianli Cai

Full Text Available Many studies have investigated the relationship between FTO gene polymorphism and polycystic ovary syndrome (PCOS susceptibility but revealed mixed results. In this study, we aimed to perform a meta-analysis to clarify this association.Published literature from PubMed, Embase and CNKI was retrieved. Meta-analysis was performed to calculate pooled odds ratio (OR with 95% confidence interval (CI using the random- or fix- effects model.A total of 5 studies (4778 cases and 4272 controls were included in our meta-analysis. The results suggested that FTO rs9939609 polymorphism (or its proxy was marginally associated with PCOS risk after adjustment for body mass index (BMI (OR = 1.26; 95%CI: 1.02-1.55. However, the marginal association was not stable after sensitivity analysis. In the subgroup analysis by ethnicity, the association was significant in East Asians (OR = 1.43, 95%CI = 1.30-1.59 but not in Caucasians (OR = 1.04, 95%CI = 0.85-1.29.Our present meta-analysis indicated that FTO rs9939609 polymorphism (or its proxy might not be associated with risk of PCOS in overall population. However, in East Asians, there might be a direct association between FTO variant and PCOS risk, which is independent of BMI (adiposity.

Systematic review, meta-analysis, and meta-regression: Successful second-line treatment for Helicobacter pylori.

Science.gov (United States)

Muñoz, Neus; Sánchez-Delgado, Jordi; Baylina, Mireia; Puig, Ignasi; López-Góngora, Sheila; Suarez, David; Calvet, Xavier

2018-06-01

Multiple Helicobacter pylori second-line schedules have been described as potentially useful. It remains unclear, however, which are the best combinations, and which features of second-line treatments are related to better cure rates. The aim of this study was to determine that second-line treatments achieved excellent (>90%) cure rates by performing a systematic review and when possible a meta-analysis. A meta-regression was planned to determine the characteristics of treatments achieving excellent cure rates. A systematic review for studies evaluating second-line Helicobacter pylori treatment was carried out in multiple databases. A formal meta-analysis was performed when an adequate number of comparative studies was found, using RevMan5.3. A meta-regression for evaluating factors predicting cure rates >90% was performed using Stata Statistical Software. The systematic review identified 115 eligible studies, including 203 evaluable treatment arms. The results were extremely heterogeneous, with 61 treatment arms (30%) achieving optimal (>90%) cure rates. The meta-analysis favored quadruple therapies over triple (83.2% vs 76.1%, OR: 0.59:0.38-0.93; P = .02) and 14-day quadruple treatments over 7-day treatments (91.2% vs 81.5%, OR; 95% CI: 0.42:0.24-0.73; P = .002), although the differences were significant only in the per-protocol analysis. The meta-regression did not find any particular characteristics of the studies to be associated with excellent cure rates. Second-line Helicobacter pylori treatments achieving>90% cure rates are extremely heterogeneous. Quadruple therapy and 14-day treatments seem better than triple therapies and 7-day ones. No single characteristic of the treatments was related to excellent cure rates. Future approaches suitable for infectious diseases-thus considering antibiotic resistances-are needed to design rescue treatments that consistently achieve excellent cure rates. © 2018 John Wiley & Sons Ltd.

Quick, “Imputation-free” meta-analysis with proxy-SNPs

Directory of Open Access Journals (Sweden)

Meesters Christian

2012-09-01

Full Text Available Abstract Background Meta-analysis (MA is widely used to pool genome-wide association studies (GWASes in order to a increase the power to detect strong or weak genotype effects or b as a result verification method. As a consequence of differing SNP panels among genotyping chips, imputation is the method of choice within GWAS consortia to avoid losing too many SNPs in a MA. YAMAS (Yet Another Meta Analysis Software, however, enables cross-GWAS conclusions prior to finished and polished imputation runs, which eventually are time-consuming. Results Here we present a fast method to avoid forfeiting SNPs present in only a subset of studies, without relying on imputation. This is accomplished by using reference linkage disequilibrium data from 1,000 Genomes/HapMap projects to find proxy-SNPs together with in-phase alleles for SNPs missing in at least one study. MA is conducted by combining association effect estimates of a SNP and those of its proxy-SNPs. Our algorithm is implemented in the MA software YAMAS. Association results from GWAS analysis applications can be used as input files for MA, tremendously speeding up MA compared to the conventional imputation approach. We show that our proxy algorithm is well-powered and yields valuable ad hoc results, possibly providing an incentive for follow-up studies. We propose our method as a quick screening step prior to imputation-based MA, as well as an additional main approach for studies without available reference data matching the ethnicities of study participants. As a proof of principle, we analyzed six dbGaP Type II Diabetes GWAS and found that the proxy algorithm clearly outperforms naïve MA on the p-value level: for 17 out of 23 we observe an improvement on the p-value level by a factor of more than two, and a maximum improvement by a factor of 2127. Conclusions YAMAS is an efficient and fast meta-analysis program which offers various methods, including conventional MA as well as inserting proxy

Developmental defects of enamel and dental caries in the primary dentition: A systematic review and meta-analysis.

Science.gov (United States)

Costa, Francine S; Silveira, Ethieli R; Pinto, Gabriela S; Nascimento, Gustavo G; Thomson, William Murray; Demarco, Flávio F

2017-05-01

This systematic review and meta-analysis evaluated the association between developmental defects of enamel and dental caries in the primary dentition. Electronic searches were performed in PubMed, Web of Knowledge, Scopus and Scielo for the identification of relevant studies. Observational studies that examined the association between developmental defects of enamel and dental caries in the deciduous dentition were included. Additionally, meta-analysis, funnel plots and sensitivity analysis were employed to synthesize the available evidence. Multivariable meta-regression analysis was performed to explore heterogeneity among studies. A total of 318 articles were identified in the electronic searches. Of those, 16 studies were included in the meta-analysis. Pooled estimates revealed that children with developmental defects of enamel had higher odds of having dental caries (OR 3.32; 95%CI 2.41-4.57), with high heterogeneity between studies (I 2 80%). Methodological characteristic of the studies, such as where it was conducted, the examined teeth and the quality of the study explained about 30% of the variability. Concerning type of defect, children with hypoplasia and diffuse opacities had higher odds of having dental caries (OR 4.28; 95%CI 2.24-8.15; OR1.42; 95%CI 1.15-1.76, respectively). This systematic review and meta-analysis demonstrates a clear association between developmental defects of enamel and dental caries in the primary dentition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Personality traits and personal values: a meta-analysis.

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Parks-Leduc, Laura; Feldman, Gilad; Bardi, Anat

2015-02-01

Personality traits and personal values are important psychological characteristics, serving as important predictors of many outcomes. Yet, they are frequently studied separately, leaving the field with a limited understanding of their relationships. We review existing perspectives regarding the nature of the relationships between traits and values and provide a conceptual underpinning for understanding the strength of these relationships. Using 60 studies, we present a meta-analysis of the relationships between the Five-Factor Model (FFM) of personality traits and the Schwartz values, and demonstrate consistent and theoretically meaningful relationships. However, these relationships were not generally large, demonstrating that traits and values are distinct constructs. We find support for our premise that more cognitively based traits are more strongly related to values and more emotionally based traits are less strongly related to values. Findings also suggest that controlling for personal scale-use tendencies in values is advisable. © 2014 by the Society for Personality and Social Psychology, Inc.

C-reactive protein gene polymorphisms and myocardial infarction risk: a meta-analysis and meta-regression.

Science.gov (United States)

Zhu, Yanbin; Liu, Tongku; He, Haitao; Sun, Yuqing; Zhuo, Fengling

2013-12-01

C-reactive protein (CRP), the classic acute-phase protein, plays an important role in the etiology of myocardial infarction (MI). Emerging evidence has shown that the common polymorphisms in the CRP gene may influence an individual's susceptibility to MI; but individually published studies showed inconclusive results. This meta-analysis aimed to derive a more precise estimation of the associations between CRP gene polymorphisms and MI risk. A literature search of PubMed, Embase, Web of Science, and China BioMedicine (CBM) databases was conducted on articles published before June 1st, 2013. Crude odds ratio (OR) with 95% confidence interval (CI) were calculated. Nine case-control studies were included with a total of 2992 MI patients and 4711 healthy controls. The meta-analysis results indicated that CRP rs3093059 (T>C) polymorphism was associated with decreased risk of MI, especially among Asian populations. However, similar associations were not observed in CRP rs1800947 (G>C) and rs2794521 (G>A) polymorphisms (all p>0.05) among both Asian and Caucasian populations. Univariate and multivariate meta-regression analyses showed that ethnicity may be a major source of heterogeneity. No publication bias was detected in this meta-analysis. In conclusion, the current meta-analysis indicates that CRP rs3093059 (T>C) polymorphism may be associated with decreased risk of MI, especially among Asian populations.

Association between the COMT Val158Met polymorphism and fibromyalgia susceptibility and fibromyalgia impact questionnaire score: a meta-analysis.

Science.gov (United States)

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

2015-01-01

The aim of this study was to explore whether the catechol-O-methyltransferase (COMT) Val158Met polymorphism is associated with susceptibility to fibromyalgia and fibromyalgia impact questionnaire (FIQ) score in fibromyalgia patients. We conducted a meta-analysis of the associations of the COMT Val158Met polymorphism with fibromyalgia risk as well as FIQ score in fibromyalgia patients. A total of 993 fibromyalgia patients and 778 controls from 10 studies on the COMT Val158Met polymorphism and 538 fibromyalgia patients from 5 studies on the COMT Val158Met polymorphism and FIQ score were included in this meta-analysis. The meta-analysis revealed an association between fibromyalgia and the COMT Met/Met + Val/Met genotype in all study subjects (odds ratio (OR) 1.635, 95 % confidence interval (CI) 1.029-2.597, p = 0.037). However, stratification by ethnicity indicated no association between the Met/Met + Val/Met genotype and fibromyalgia in the European and Turkish populations (OR 1.202, 95 % CI 0.876-1.649, p = 0.255; OR 2.132, 95 % CI 0.764-5.949, p = 0.148, respectively). Analysis using other genetic models showed no association between the COMT Val158Met polymorphism and fibromyalgia. The meta-analysis also revealed that the FIQ score was significantly higher in individuals with the COMT Met/Met genotype than in those with the Val/Val genotype [weighted mean difference (WMD) = 14.39, 95 % CI 3.316-25.48, p = 0.011] and the Val/Met genotype (WMD = 5.108, 95 % CI 2.212-4.891, p = 0.021). This meta-analysis identified an association between fibromyalgia risk and the COMT Val158Met polymorphism as well as the FIQ score in fibromyalgia patients.

Genome-wide meta-analysis identifies 56 bone mineral density loci and reveals 14 loci associated with risk of fracture

NARCIS (Netherlands)

K. Estrada Gil (Karol); U. Styrkarsdottir (Unnur); E. Evangelou (Evangelos); Y.-H. Hsu (Yi-Hsiang); E.L. Duncan (Emma); E.E. Ntzani (Evangelia); L. Oei (Ling); O.M.E. Albagha (Omar M.); N. Amin (Najaf); J.P. Kemp (John); D.L. Koller (Daniel); G. Li (Guo); C.-T. Liu (Ching-Ti); R.L. Minster (Ryan); A. Moayyeri (Alireza); L. Vandenput (Liesbeth); D. Willner (Dana); S.-M. Xiao (Su-Mei); L.M. Yerges-Armstrong (Laura); H.-F. Zheng (Hou-Feng); N. Alonso (Nerea); J. Eriksson (Joel); C.M. Kammerer (Candace); S. Kaptoge (Stephen); P.J. Leo (Paul); G. Thorleifsson (Gudmar); S.G. Wilson (Scott); J.F. Wilson (James); V. Aalto (Ville); T.A. van Alen (Theo); A.K. Aragaki (Aaron); T. Aspelund (Thor); J.R. Center (Jacqueline); Z. Dailiana (Zoe); C. Duggan; M. Garcia (Melissa); N. Garcia-Giralt (Natàlia); S. Giroux (Sylvie); G. Hallmans (Göran); L.J. Hocking (Lynne); L.B. Husted (Lise Bjerre); K. Jameson (Karen); R. Khusainova (Rita); G.S. Kim (Ghi Su); C. Kooperberg (Charles); T. Koromila (Theodora); M. Kruk (Marcin); M. Laaksonen (Marika); A.Z. LaCroix (Andrea); S.U. Lee (Seung); P.C. Leung (Ping); J.R. Lewis (Joshua); L. Masi (Laura); S. Mencej-Bedrac (Simona); T.V. Nguyen (Tuan); X. Nogues (Xavier); M.S. Patel (Millan); J. Prezelj (Janez); L.M. Rose (Lynda); S. Scollen (Serena); K. Siggeirsdottir (Kristin); G.D. Smith; O. Svensson (Olle); S. Trompet (Stella); O. Trummer (Olivia); N.M. van Schoor (Natasja); M.M. Woo (Margaret M.); K. Zhu (Kun); S. Balcells (Susana); M.L. Brandi; B.M. Buckley (Brendan M.); S. Cheng (Sulin); C. Christiansen; C. Cooper (Charles); G.V. Dedoussis (George); I. Ford (Ian); M. Frost (Morten); D. Goltzman (David); J. González-Macías (Jesús); M. Kähönen (Mika); M. Karlsson (Magnus); E.K. Khusnutdinova (Elza); J.-M. Koh (Jung-Min); P. Kollia (Panagoula); B.L. Langdahl (Bente); W.D. Leslie (William); P. Lips (Paul); O. Ljunggren (Östen); R. Lorenc (Roman); J. Marc (Janja); D. Mellström (Dan); B. Obermayer-Pietsch (Barbara); D. Olmos (David); U. Pettersson-Kymmer (Ulrika); D.M. Reid (David); J.A. Riancho (José); P.M. Ridker (Paul); M.F. Rousseau (Francois); P.E.S. Lagboom (P Eline); N.L.S. Tang (Nelson L.); R. Urreizti (Roser); W. Van Hul (Wim); J. Viikari (Jorma); M.T. Zarrabeitia (María); Y.S. Aulchenko (Yurii); M.C. Castaño Betancourt (Martha); E. Grundberg (Elin); L. Herrera (Lizbeth); T. Ingvarsson (Torvaldur); H. Johannsdottir (Hrefna); T. Kwan (Tony); R. Li (Rui); R.N. Luben (Robert); M.C. Medina-Gomez (Carolina); S. Th Palsson (Stefan); S. Reppe (Sjur); J.I. Rotter (Jerome); G. Sigurdsson (Gunnar); J.B.J. van Meurs (Joyce); D.J. Verlaan (Dominique); F.M. Williams (Frances); A.R. Wood (Andrew); Y. Zhou (Yanhua); K.M. Gautvik (Kaare); T. Pastinen (Tomi); S. Raychaudhuri (Soumya); J.A. Cauley (Jane); D.I. Chasman (Daniel); G.R. Clark (Graeme); S. Cummings; P. Danoy (Patrick); E.M. Dennison (Elaine); R. Eastell (Richard); J.A. Eisman (John); V. Gudnason (Vilmundur); A. Hofman (Albert); R.D. Jackson (Rebecca); G. Jones (Graeme); J.W. Jukema (Jan Wouter); K-T. Khaw (Kay-Tee); T. Lehtimäki (Terho); Y. Liu (YongMei); M. Lorentzon (Mattias); E.V. McCloskey (Eugene); B.D. Mitchell (Braxton); K. Nandakumar (Kannabiran); G.C. Nicholson (Geoffrey); B.A. Oostra (Ben); M. Peacock (Munro); H.A.P. Pols (Huib); R.L. Prince (Richard); O. Raitakari (Olli); I.R. Reid (Ian); J. Robbins (John); P.N. Sambrook (Philip); P.C. Sham (Pak); A.R. Shuldiner (Alan); F.A. Tylavsky (Frances); C.M. van Duijn (Cornelia); N.J. Wareham (Nick); L.A. Cupples (Adrienne); M.J. Econs (Michael); D.M. Evans (David); T.B. Harris (Tamara); A.W.C. Kung (Annie); B.M. Psaty (Bruce); J. Reeve (Jonathan); T.D. Spector (Timothy); E.A. Streeten (Elizabeth); M.C. Zillikens (Carola); U. Thorsteinsdottir (Unnur); C. Ohlsson (Claes); D. Karasik (David); J.B. Richards (Brent); M.A. Brown (Matthew); J-A. Zwart (John-Anker); A.G. Uitterlinden (André); S.H. Ralston (Stuart); J.P.A. Ioannidis (John); D.P. Kiel (Douglas); F. Rivadeneira Ramirez (Fernando)

2012-01-01

textabstractBone mineral density (BMD) is the most widely used predictor of fracture risk. We performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and east Asian ancestry. We tested the top

Alcohol and the risk of sleep apnoea: a systematic review and meta-analysis.

Science.gov (United States)

Simou, Evangelia; Britton, John; Leonardi-Bee, Jo

2018-02-01

A systematic review and meta-analysis of the association between alcohol consumption and risk of sleep apnoea in adults. We searched Medline, EMBASE and Web of Science databases from 1985 to 2015 for comparative epidemiological studies assessing the relation between alcohol consumption and sleep apnoea. Two authors independently screened and extracted data. Random effects meta-analysis was used to estimate pooled effect sizes with 95% confidence intervals (CI). Heterogeneity was quantified using I 2 and explored using subgroup analyses based on study exposure and outcome measures, quality, design, adjustment for confounders and geographical location. Publication bias was assessed using a funnel plot and Egger's test. We identified 21 studies from which estimates of relative risk could be obtained. Meta-analysis of these estimates demonstrated that higher levels of alcohol consumption increased the risk of sleep apnoea by 25% (RR 1.25, 95%CI 1.13-1.38, I 2  = 82%, p Country locations. We detected evidence of publication bias (p = 0.001). A further eight included studies reported average alcohol consumption in people with and without sleep apnoea. Meta-analysis revealed that mean alcohol intake was two units/week higher in those with sleep apnoea, but this difference was not statistically significant (p = 0.41). These findings suggest that alcohol consumption is associated with a higher risk of sleep apnoea, further supporting evidence that reducing alcohol intake is of potential therapeutic and preventive value in this condition. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

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

Science.gov (United States)

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

2016-08-01

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

A meta-analysis of the effects of β-adrenergic blockers in chronic heart failure.

Science.gov (United States)

Zhang, Xiaojian; Shen, Chengwu; Zhai, Shujun; Liu, Yukun; Yue, Wen-Wei; Han, Li

2016-10-01

Adrenergic β-blockers are drugs that bind to, but do not activate β-adrenergic receptors. Instead they block the actions of β-adrenergic agonists and are used for the treatment of various diseases such as cardiac arrhythmias, angina pectoris, myocardial infarction, hypertension, headache, migraines, stress, anxiety, prostate cancer, and heart failure. Several meta-analysis studies have shown that β-blockers improve the heart function and reduce the risks of cardiovascular events, rate of mortality, and sudden death through chronic heart failure (CHF) of patients. The present study identified results from recent meta-analyses of β-adrenergic blockers and their usefulness in CHF. Databases including Medline/Embase/Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed were searched for the periods May, 1985 to March, 2011 and June, 2013 to August, 2015, and a number of studies identified. Results of those studies showed that use of β-blockers was associated with decreased sudden cardiac death in patients with heart failure. However, contradictory results have also been reported. The present meta-analysis aimed to determine the efficacy of β-blockers on mortality and morbidity in patients with heart failure. The results showed that mortality was significantly reduced by β-blocker treatment prior to the surgery of heart failure patients. The results from the meta-analysis studies showed that β-blocker treatment in heart failure patients correlated with a significant decrease in long-term mortality, even in patients that meet one or more exclusion criteria of the MERIT-HF study. In summary, the findings of the current meta-analysis revealed beneficial effects different β-blockers have on patients with heart failure or related heart disease.

Evaluation of Open and Minimally Invasive Adrenalectomy: A Systematic Review and Network Meta-analysis.

Science.gov (United States)

Heger, Patrick; Probst, Pascal; Hüttner, Felix J; Gooßen, Käthe; Proctor, Tanja; Müller-Stich, Beat P; Strobel, Oliver; Büchler, Markus W; Diener, Markus K

2017-11-01

Adrenalectomy can be performed via open and various minimally invasive approaches. The aim of this systematic review was to summarize the current evidence on surgical techniques of adrenalectomy. Systematic literature searches (MEDLINE, EMBASE, Web of Science, Cochrane Library) were conducted to identify randomized controlled trials (RCTs) and controlled clinical trials (CCTs) comparing at least two surgical procedures for adrenalectomy. Statistical analyses were performed, and meta-analyses were conducted. Furthermore, an indirect comparison of RCTs and a network meta-analysis of CCTs were carried out for each outcome. Twenty-six trials (1710 patients) were included. Postoperative complication rates did not show differences for open and minimally invasive techniques. Operation time was significantly shorter for open adrenalectomy than for the robotic approach (p meta-analysis showed open adrenalectomy to be the fastest technique. Blood loss was significantly reduced in the robotic arm compared with open and laparoscopic adrenalectomy (p = 0.01). Length of hospital stay (LOS) was significantly lower after conventional laparoscopy than open adrenalectomy in CCTs (p meta-analysis revealed the lowest LOS after retroperitoneoscopic adrenalectomy. Minimally invasive adrenalectomy is safe and should be preferred over open adrenalectomy due to shorter LOS, lower blood loss, and equivalent complication rates. The retroperitoneoscopic access features the shortest LOS and operating time. Further high-quality RCTs are warranted, especially to compare the posterior retroperitoneoscopic and the transperitoneal robotic approach.

Evaluating the Effect of Virtual Reality Temporal Bone Simulation on Mastoidectomy Performance: A Meta-analysis.

Science.gov (United States)

Lui, Justin T; Hoy, Monica Y

2017-06-01

Background The increasing prevalence of virtual reality simulation in temporal bone surgery warrants an investigation to assess training effectiveness. Objectives To determine if temporal bone simulator use improves mastoidectomy performance. Data Sources Ovid Medline, Embase, and PubMed databases were systematically searched per the PRISMA guidelines. Review Methods Inclusion criteria were peer-reviewed publications that utilized quantitative data of mastoidectomy performance following the use of a temporal bone simulator. The search was restricted to human studies published in English. Studies were excluded if they were in non-peer-reviewed format, were descriptive in nature, or failed to provide surgical performance outcomes. Meta-analysis calculations were then performed. Results A meta-analysis based on the random-effects model revealed an improvement in overall mastoidectomy performance following training on the temporal bone simulator. A standardized mean difference of 0.87 (95% CI, 0.38-1.35) was generated in the setting of a heterogeneous study population ( I 2 = 64.3%, P virtual reality simulation temporal bone surgery studies, meta-analysis calculations demonstrate an improvement in trainee mastoidectomy performance with virtual simulation training.

Metallothionein - immunohistochemical cancer biomarker: a meta-analysis.

Directory of Open Access Journals (Sweden)

Jaromir Gumulec

Full Text Available Metallothionein (MT has been extensively investigated as a molecular marker of various types of cancer. In spite of the fact that numerous reviews have been published in this field, no meta-analytical approach has been performed. Therefore, results of to-date immunohistochemistry-based studies were summarized using meta-analysis in this review. Web of science, PubMed, Embase and CENTRAL databases were searched (up to April 30, 2013 and the eligibility of individual studies and heterogeneity among the studies was assessed. Random and fixed effects model meta-analysis was employed depending on the heterogeneity, and publication bias was evaluated using funnel plots and Egger's tests. A total of 77 studies were included with 8,015 tissue samples (4,631 cases and 3,384 controls. A significantly positive association between MT staining and tumors (vs. healthy tissues was observed in head and neck (odds ratio, OR 9.95; 95% CI 5.82-17.03 and ovarian tumors (OR 7.83; 1.09-56.29, and a negative association was ascertained in liver tumors (OR 0.10; 0.03-0.30. No significant associations were identified in breast, colorectal, prostate, thyroid, stomach, bladder, kidney, gallbladder, and uterine cancers and in melanoma. While no associations were identified between MT and tumor staging, a positive association was identified with the tumor grade (OR 1.58; 1.08-2.30. In particular, strong associations were observed in breast, ovarian, uterine and prostate cancers. Borderline significant association of metastatic status and MT staining were determined (OR 1.59; 1.03-2.46, particularly in esophageal cancer. Additionally, a significant association between the patient prognosis and MT staining was also demonstrated (hazard ratio 2.04; 1.47-2.81. However, a high degree of inconsistence was observed in several tumor types, including colorectal, kidney and prostate cancer. Despite the ambiguity in some tumor types, conclusive results are provided in the tumors of

Genome-wide meta-analysis identifies 56 bone mineral density loci and reveals 14 loci associated with risk of fracture

DEFF Research Database (Denmark)

Estrada, Karol; Styrkarsdottir, Unnur; Evangelou, Evangelos

2012-01-01

Bone mineral density (BMD) is the most widely used predictor of fracture risk. We performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and east Asian ancestry. We tested the top BMD-associ...

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

Science.gov (United States)

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

2017-01-01

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

Road safety effects of roundabouts: A meta-analysis.

Science.gov (United States)

Elvik, Rune

2017-02-01

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

Systematic reviews with meta-analysis: Why, when, and how?

NARCIS (Netherlands)

Crocetti, E.

2016-01-01

Systematic reviews with meta-analysis represent the gold standard for conducting reliable and transparent reviews of the literature. The purpose of this article is threefold: (a) to address why and when it is worthwhile to conduct a systematic review with meta-analysis, covering advantages of this

FOXO3 variants are beneficial for longevity in Southern Chinese living in the Red River Basin: A case-control study and meta-analysis.

Science.gov (United States)

Sun, Liang; Hu, Caiyou; Zheng, Chenguang; Qian, Yu; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, KeYan; Gong, Huan; Zhang, Zheng; Huang, Jin; Zhou, Qin; Yang, Ze

2015-04-27

Forkhead box class O (FOXO) transcription factors play a crucial role in longevity across species. Several polymorphisms in FOXO3 were previously reported to be associated with human longevity. However, only one Chinese replication study has been performed so far. To verify the role of FOXO3 in southern Chinese in the Red River Basin, a community-based case-control study was conducted, and seven polymorphisms were genotyped in 1336 participants, followed by a meta-analysis of eight case-control studies that included 5327 longevity cases and 4608 controls. In our case-control study, we found rs2802288*A and rs2802292*G were beneficial to longevity after Bonferroni correction (pallele = 0.005, OR = 1.266; pallele = 0.026, OR = 1.207). In addition, in the longevity group, carriers with rs2802288*A and rs2802292*G presented reduced HbA1c (p = 0.001), and homozygotes of rs2802292*GG presented improved HOMA-IR (p = 0.014). The meta-analysis further revealed the overall contribution of rs2802288*A and rs2802292*G to longevity. However, our stratified analysis revealed that rs2802292*G might act more strongly in Asians than Europeans, for enhancement of longevity. In conclusion, our study provides convincing evidence for a significant association between the rs2802288*A and rs2802292*G gene variants in FOXO3 and human longevity, and adds the Southern Chinese in the Red River Basin to the growing number of human replication populations.

Hypothyroidism and carpal tunnel syndrome: a meta-analysis.

Science.gov (United States)

Shiri, Rahman

2014-12-01

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

Telomerase reverse transcriptase locus polymorphisms and cancer risk: a field synopsis and meta-analysis.

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Mocellin, Simone; Verdi, Daunia; Pooley, Karen A; Landi, Maria T; Egan, Kathleen M; Baird, Duncan M; Prescott, Jennifer; De Vivo, Immaculata; Nitti, Donato

2012-06-06

Several recent studies have provided evidence that polymorphisms in the telomerase reverse transcriptase (TERT) gene sequence are associated with cancer development, but a comprehensive synopsis is not available. We conducted a systematic review and meta-analysis of the available molecular epidemiology data regarding the association between TERT locus polymorphisms and predisposition to cancer. A systematic review of the English literature was conducted by searching PubMed, Embase, Cancerlit, Google Scholar, and ISI Web of Knowledge databases for studies on associations between TERT locus polymorphisms and cancer risk. Random-effects meta-analysis was performed to pool per-allele odds ratios for TERT locus polymorphisms and risk of cancer, and between-study heterogeneity and potential bias sources (eg, publication and chasing bias) were assessed. Because the TERT locus includes the cleft lip and palate transmembrane 1-like (CLPTM1L) gene, which is in linkage disequilibrium with TERT, CLPTM1L polymorphisms were also analyzed. Cumulative evidence for polymorphisms with statistically significant associations was graded as "strong," "moderate," and "weak" according to the Venice criteria. The joint population attributable risk was calculated for polymorphisms with strong evidence of association. Eighty-five studies enrolling 490 901 subjects and reporting on 494 allelic contrasts were retrieved. Data were available on 67 TERT locus polymorphisms and 24 tumor types, for a total of 221 unique combinations of polymorphisms and cancer types. Upon meta-analysis, a statistically significant association with the risk of any cancer type was found for 22 polymorphisms. Strong, moderate, and weak cumulative evidence for association with at least one tumor type was demonstrated for 11, 9, and 14 polymorphisms, respectively. For lung cancer, which was the most studied tumor type, the estimated joint population attributable risk for three polymorphisms (TERT rs2736100, intergenic

Lateral Epicondylitis and Physical Exposure at Work? A Review of Prospective Studies and Meta-Analysis.

Science.gov (United States)

Descatha, Alexis; Albo, Francesco; Leclerc, Annette; Carton, Matthieu; Godeau, Diane; Roquelaure, Yves; Petit, Audrey; Aublet-Cuvelier, Agnès

2016-11-01

In view of recent published studies, a meta-analysis was undertaken on prospective studies in order to assess any association between lateral epicondylitis and physical exposure at work. Using the key words "lateral epicondylitis" AND "occupational" AND ("cohort" OR "longitudinal," OR "incidence") without limitations on the language or year of publication, original prospective studies were selected from 4 databases (PubMed, Scopus, Web of Science, and Base de Données de Santé Publique) after 2 rounds (valid design, valid association reported, and valid work exposure). Relevant associations between physical exposure at work and incident lateral epicondylitis were extracted from the articles, and a meta-risk was calculated using the generic variance approach (meta-odds ratios [meta-ORs]). From 2001 to 2014, 5 prospective studies were included. Among 6,922 included subjects (and 3,449 who were followed), 256 cases of incident lateral epicondylitis were diagnosed 2.5-6 years after baseline. All the published studies found a significant estimation of relative risk for a positive association between combined biomechanic exposure involving the wrist and/or elbow and incidence of lateral epicondylitis. The overall meta-OR was 2.6 (95% confidence interval 1.9-3.5), with a low heterogeneity (Q = 1.4, P > 0.05). Funnel plots and Egger's test did not suggest major publication bias. The results of this meta-analysis strongly support the hypothesis of an association between biomechanic exposure involving the wrist and/or elbow at work and incidence of lateral epicondylitis. © 2016, American College of Rheumatology.

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

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

2017-10-25

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

Sleep duration and obesity in children: A systematic review and meta-analysis of prospective cohort studies.

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Li, Lian; Zhang, Shuang; Huang, Yubei; Chen, Kexin

2017-04-01

Childhood obesity is a major public problem worldwide, and sleep duration may be associated with childhood obesity. We conducted a systematic review and meta-analysis of prospective cohort studies to estimate the associations between sleep duration and obesity/body mass index (BMI) in children. PubMed, Embase and the Cochrane Library were searched. For the meta-analysis, the pooled relative risk (RR) and 95% confidence intervals (CI) were estimated to reveal the association between short sleep duration and obesity. For the review, the outcomes focused on BMI change or subsequent BMI status. A total of 12 studies (15 populations) met the criteria for inclusion in the meta-analysis. Short sleep duration was significantly associated with obesity (RR: 1.45; 95% CI: 1.14-1.85). After excluding two cohorts that substantially affected the heterogeneity, the pooled results remained significant (RR: 1.30; 95% CI: 1.20-1.42), and the association was not substantially altered in the subgroup analysis. In addition, we summarised 24 studies that met the criteria for our review of the relationship between sleeping and BMI. The present meta-analysis indicated that short sleep duration increased the risk of childhood obesity. Public health efforts that encourage children to have sufficient sleep time may be important in combating obesity. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

Prognostic value of lncRNAs in lung carcinoma: a meta-analysis.

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Fan, Fan; Zhu, Zhengqiu; Gao, Chao; Liu, Yun; Wang, Baoqing; Wang, Ziquan; Feng, Jifeng

2017-10-10

Many different long non-coding RNAs (lncRNAs) have been reported to be abnormally expressed in lung carcinoma and may thus serve as prognostic biomarkers for this disease. We conducted this meta-analysis, which included a total of 30 studies identified via searches of PubMed, Embase, Medline, and Web of Science and included 2912 patients from China (28), Germany (1), and Japan (1), to investigate the prognostic value of different lncRNAs in lung carcinoma. The results revealed that lncRNA transcription levels were significantly associated with overall survival in lung cancer patients (HR:1.46, 95% CI: 1.16-1.83, P = 0.000). However, lncRNA transcription levels were not associated with progression-free survival (PFS) (HR: 1.55, 95% CI: 0.50-4.80, P = 0.449). Further analysis showed that high lncRNA transcription levels were significantly associated with tumour-node-metastasis (TNM) stage (III/IV vs I/II: RR = 1.339, 95% CI: 1.046-1.716, P = 0.012), lymph node metastasis (positive vs negative: RR = 1.442, 95% CI: 1.103-1.885, P = 0.007), and distant metastasis (yes vs no: RR = 3.187,95% CI: 1.393-7.294, P = 0.006). Taken together, the results of our present meta-analysis revealed that lncRNAs may be useful prognostic markers for lung carcinoma and may also have value as biomarkers for TNM stage, lymph node metastasis and distant metastasis.

Moyer's method of mixed dentition analysis: a meta-analysis ...

African Journals Online (AJOL)

The applicability of tables derived from the data Moyer used to other ethnic groups has ... This implies that Moyer's method of prediction may have population variations. ... Key Words: meta-analysis, mixed dentition analysis, Moyer's method

Exposure to organochlorine pollutants and type 2 diabetes: a systematic review and meta-analysis.

Directory of Open Access Journals (Sweden)

Mengling Tang

Full Text Available OBJECTIVE: Though exposure to organochlorine pollutants (OCPs is considered a risk factor for type 2 diabetes (T2DM, epidemiological evidence for the association remains controversial. A systematic review and meta-analysis was applied to quantitatively evaluate the association between exposure to OCPs and incidence of T2DM and pool the inconsistent evidence. DESIGN AND METHODS: Publications in English were searched in MEDLINE and WEB OF SCIENCE databases and related reference lists up to August 2013. Quantitative estimates and information regarding study characteristics were extracted from 23 original studies. Quality assessments of external validity, bias, exposure measurement and confounding were performed, and subgroup analyses were conducted to examine the heterogeneity sources. RESULTS: We retrieved 23 eligible articles to conduct this meta-analysis. OR (odds ratio or RR (risk ratio estimates in each subgroup were discussed, and the strong associations were observed in PCB-153 (OR, 1.52; 95% CI, 1.19-1.94, PCBs (OR, 2.14; 95% CI, 1.53-2.99, and p,p'-DDE (OR, 1.33; 95% CI, 1.15-1.54 based on a random-effects model. CONCLUSIONS: This meta-analysis provides quantitative evidence supporting the conclusion that exposure to organochlorine pollutants is associated with an increased risk of incidence of T2DM.

CrossFit Overview: Systematic Review and Meta-analysis.

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

2018-02-26

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

Prevalence of retinopathy of prematurity in Iran: asystematic review and Meta-analysis

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Saman Maroufizadeh

2017-08-01

Full Text Available AIM: To estimate overall prevalence of retinopathy of prematurity (ROP in Iran using a systematic review and Meta-analysis. METHODS: A systematic review and Meta-analysis was performed of all published studies pertaining to prevalence of ROP using international and national electronic databases (ISI Web of Sciences, PubMed, Scopus, Google Scholar, SID, MagIran, and IranMedex from their inception until May 2016 with standard keywords. Begg and Egger tests were used to examine the publication bias and Cochran test and I2 statistics were used to evaluate the statistical heterogeneity. Pooled estimate of the prevalence of ROP were calculated using random effects Meta-analysis. RESULTS: The publication bias assumption was rejected by Egger tests with P-value equal to 0.024. The results of Cochran test and I2 statistics revealed substantial heterogeneity (Q=1099.02, df=25, I2=97.7%, P=0.001. The overall prevalence of ROP using the random effect model in Iran was 26.1% (95% CI: 20.3%-31.8%. CONCLUSION: The prevalence of ROP is relatively high in Iran. Low birth weight and gestational age are significant risk factors for the disease. Improved care, including oxygen delivery and monitoring, for preterm babies in all facility settings would reduce the number of babies affected with ROP.

Meta-analysis in a nutshell: Techniques and general findings

DEFF Research Database (Denmark)

Paldam, Martin

2015-01-01

The purpose of this article is to introduce the technique and main findings of meta-analysis to the reader, who is unfamiliar with the field and has the usual objections. A meta-analysis is a quantitative survey of a literature reporting estimates of the same parameter. The funnel showing...

Common and distinct neural correlates of personal and vicarious reward: A quantitative meta-analysis

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Morelli, Sylvia A.; Sacchet, Matthew D.; Zaki, Jamil

2015-01-01

Individuals experience reward not only when directly receiving positive outcomes (e.g., food or money), but also when observing others receive such outcomes. This latter phenomenon, known as vicarious reward, is a perennial topic of interest among psychologists and economists. More recently, neuroscientists have begun exploring the neuroanatomy underlying vicarious reward. Here we present a quantitative whole-brain meta-analysis of this emerging literature. We identified 25 functional neuroimaging studies that included contrasts between vicarious reward and a neutral control, and subjected these contrasts to an activation likelihood estimate (ALE) meta-analysis. This analysis revealed a consistent pattern of activation across studies, spanning structures typically associated with the computation of value (especially ventromedial prefrontal cortex) and mentalizing (including dorsomedial prefrontal cortex and superior temporal sulcus). We further quantitatively compared this activation pattern to activation foci from a previous meta-analysis of personal reward. Conjunction analyses yielded overlapping VMPFC activity in response to personal and vicarious reward. Contrast analyses identified preferential engagement of the nucleus accumbens in response to personal as compared to vicarious reward, and in mentalizing-related structures in response to vicarious as compared to personal reward. These data shed light on the common and unique components of the reward that individuals experience directly and through their social connections. PMID:25554428

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

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

2015-01-01

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

Statin use and the risk of Clostridium difficile infection: a systematic review with meta-analysis.

Science.gov (United States)

Tariq, Raseen; Mukhija, Dhruvika; Gupta, Arjun; Singh, Siddharth; Pardi, Darrell S; Khanna, Sahil

2018-01-01

Statins have pleiotropic effects beyond cholesterol lowering by immune modulation. The association of statins with primary Clostridium difficile infection (CDI) is unclear as studies have reported conflicting findings. We performed a systematic review and meta-analysis to evaluate the association between statin use and CDI. We searched MEDLINE, Embase, and Web of Science from January 1978 to December 2016 for studies assessing the association between statin use and CDI. The Newcastle-Ottawa Scale was used to assess the methodologic quality of included studies. Weighted summary estimates were calculated using generalized inverse variance with random-effects model. Eight studies (6 case-control and 2 cohort) were included in the meta-analysis, which comprised 156,722 patients exposed to statins and 356,185 controls, with 34,849 total cases of CDI available in 7 studies. The rate of CDI in patients with statin use was 4.3%, compared with 7.8% in patients without statin use. An overall meta-analysis of 8 studies using the random-effects model demonstrated that statins may be associated with a decreased risk of CDI (maximally adjusted odds ratio [OR], 0.80; 95% CI, 0.66-0.97; P =0.02). There was significant heterogeneity among the studies, with an I 2 of 79%. No publication bias was seen. Meta-analysis of studies that adjusted for confounders revealed no protective effect of statins (adjusted OR, 0.84; 95% CI, 0.70-1.01; P =0.06, I 2 =75%). However, a meta-analysis of only full-text studies using the random-effects model demonstrated a decreased risk of CDI with the use of statins (OR 0.77; 95% CI, 0.61-0.99; P =0.04, I 2 =85%). Meta-analyses of existing studies suggest that patients prescribed a statin may be at decreased risk for CDI. The results must be interpreted with caution given the significant heterogeneity and lack of benefit on analysis of studies that adjusted for confounders.

Traumatic stress and accelerated DNA methylation age: A meta-analysis.

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Wolf, Erika J; Maniates, Hannah; Nugent, Nicole; Maihofer, Adam X; Armstrong, Don; Ratanatharathorn, Andrew; Ashley-Koch, Allison E; Garrett, Melanie; Kimbrel, Nathan A; Lori, Adriana; Va Mid-Atlantic Mirecc Workgroup; Aiello, Allison E; Baker, Dewleen G; Beckham, Jean C; Boks, Marco P; Galea, Sandro; Geuze, Elbert; Hauser, Michael A; Kessler, Ronald C; Koenen, Karestan C; Miller, Mark W; Ressler, Kerry J; Risbrough, Victoria; Rutten, Bart P F; Stein, Murray B; Ursano, Robert J; Vermetten, Eric; Vinkers, Christiaan H; Uddin, Monica; Smith, Alicia K; Nievergelt, Caroline M; Logue, Mark W

2018-06-01

Recent studies examining the association between posttraumatic stress disorder (PTSD) and accelerated aging, as defined by DNA methylation-based estimates of cellular age that exceed chronological age, have yielded mixed results. We conducted a meta-analysis of trauma exposure and PTSD diagnosis and symptom severity in association with accelerated DNA methylation age using data from 9 cohorts contributing to the Psychiatric Genomics Consortium PTSD Epigenetics Workgroup (combined N = 2186). Associations between demographic and cellular variables and accelerated DNA methylation age were also examined, as was the moderating influence of demographic variables. Meta-analysis of regression coefficients from contributing cohorts revealed that childhood trauma exposure (when measured with the Childhood Trauma Questionnaire) and lifetime PTSD severity evidenced significant, albeit small, meta-analytic associations with accelerated DNA methylation age (ps = 0.028 and 0.016, respectively). Sex, CD4T cell proportions, and natural killer cell proportions were also significantly associated with accelerated DNA methylation age (all ps age. There was no evidence of moderation of the trauma or PTSD variables by demographic factors. Results suggest that traumatic stress is associated with advanced epigenetic age and raise the possibility that cells integral to immune system maintenance and responsivity play a role in this. This study highlights the need for additional research into the biological mechanisms linking traumatic stress to accelerated DNA methylation age and the importance of furthering our understanding of the neurobiological and health consequences of PTSD. Published by Elsevier Ltd.

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

Science.gov (United States)

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

2018-05-07

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

Meta-analysis in epidemiology | Yach | South African Medical Journal

African Journals Online (AJOL)

Meta-analysis is the structured and systematic qualitative and quantitative integration of the results of several independent studies (Le. the epidemiology of results). As in any epidemiological study, a meta-analysis needs to start with clearly stated aims and objectives. Attention needs to be paid to selection bias in selecting ...

Plasma ET-1 Concentrations are Elevated in Patients with Hypertension - Meta-Analysis of Clinical Studies.

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Xu, Mei; Lu, Yong-Ping; Hasan, Ahmed Abdallah; Hocher, Berthold

2017-01-01

A recent study revealed that global overexpression of ET-1 causes a slight reduction in systemic blood pressure. Moreover, heterozygous ET-1 knockout mice are hypertensive. The role of ET-1 in human hypertension was so far not addressed by a strict meta-analysis of published human clinical studies. We included studies published between January 1, 1990 and February 28, 2017. We included case control studies analyzing untreated essential hypertension or hypertensive patients where antihypertensive medication was discontinued for at least two weeks. Based on the principle of Cochrane systematic reviews, case control studies (CCSs) in PubMed (Medline) and Google Scholar designed to identify the role of endothelin-1 (ET-1) in the pathophysiological of hypertension were screened. Review Manager Version 5.0 (Rev-Man 5.0) was applied for statistical analysis. Mean difference and 95% confidence interval (CI) were shown in inverse variance (IV) fixed-effects model or IV random-effects models. Eleven studies fulfilling our in- and exclusion criteria were eligible for this meta-analysis. These studies included 450 hypertensive patients and 328 controls. Our meta-analysis revealed that ET-1 plasma concentrations were higher in hypertensive patients as compared to the control patients [mean difference between groups 1.57 pg/mL, 95%CI [0.47∼2.68, P = 0.005]. These finding were driven by patients having systolic blood pressure higher than 160 mmHg and diastolic blood pressure higher than 100 mmHg. This meta-analysis showed that hypertensive patients do have elevated plasma ET-1 concentrations. This finding is driven by those patients with high systolic/diastolic blood pressure. Given that the ET-1 gene did not appear in any of the whole genome association studies searching for hypertension associated gene loci, it is very likely that the elevated plasma ET-1 concentrations in hypertensive patients are secondary to hypertension and may reflect endothelial cell damage. © 2017 The

Fatal flaws in a recent meta-analysis on abortion and mental health

OpenAIRE

Steinberg, Julia R.; Trussell, James; Hall, Kelli; Guthrie, Kate

2012-01-01

Similar to other reviews within the last 4 years, a thorough review by the Royal College of Psychiatrists, published in December 2011, found that compared to delivery of an unintended pregnancy, abortion does not increase women’s risk of mental health problems. In contrast, a meta-analysis published in September 2011 concluded that abortion increases women’s risk of mental health problems by 81% and that 10% of mental health problems are attributable to abortions. Like others, we strongly que...

Disclosure of sensitive behaviors across self-administered survey modes: a meta-analysis.

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Gnambs, Timo; Kaspar, Kai

2015-12-01

In surveys, individuals tend to misreport behaviors that are in contrast to prevalent social norms or regulations. Several design features of the survey procedure have been suggested to counteract this problem; particularly, computerized surveys are supposed to elicit more truthful responding. This assumption was tested in a meta-analysis of survey experiments reporting 460 effect sizes (total N =125,672). Self-reported prevalence rates of several sensitive behaviors for which motivated misreporting has been frequently observed were compared across self-administered paper-and-pencil versus computerized surveys. The results revealed that computerized surveys led to significantly more reporting of socially undesirable behaviors than comparable surveys administered on paper. This effect was strongest for highly sensitive behaviors and surveys administered individually to respondents. Moderator analyses did not identify interviewer effects or benefits of audio-enhanced computer surveys. The meta-analysis highlighted the advantages of computerized survey modes for the assessment of sensitive topics.

BMI levels with MS Bone mineral density levels in adults with multiple sclerosis: a meta-analysis.

Science.gov (United States)

Huang, Zhongming; Qi, Yiying; Du, Shaohua; Chen, Guangnan; Yan, Weiqi

2015-01-01

Multiple sclerosis (MS) and osteoporosis (OP) affect a substantial proportion of the population. Accumulating evidence suggests that MS patients are at high risk for OP. We performed a meta-analysis to identify risk factors for lowered bone mineral density (BMD) in MS patients. We searched for articles within the Medline, Embase and Cochrane Library databases, published up to March 2014, pertaining to associations between MS and BMD. A total of 11 studies was included in the meta-analysis. The analysis indicated that MS patients have reduced lumbar spine, femur neck, and hip BMD compared with healthy controls (lumbar spine, standardized mean difference (SMD) = -0.76, 95% CI: -1.07, -0.45; femur neck, SMD = -0.56, 95% CI: -0.84, -0.29; and hip, SMD = -0.62, 95% CI: -0.96, -0.29). Further subgroup analysis revealed that a disease duration of >7 years, total steroid dose during the disease of >15 g, and an Expanded Disability Status Scale (EDSS) score of > 3, increased the risk of reduced BMD in the lumbar spine and femoral neck, but not in the hip. Meta-regression analysis did not explain the heterogeneity in the clinical characteristics or outcome definitions. Our meta-analysis suggests that MS patients have reduced overall BMD compared with healthy controls. Furthermore, disease duration (>7 years), total steroid dose (>15 g), and EDSS score (>3) are risk factors for reduced BMD in MS patients.

Parkinson's disease and intensive exercise therapy--a systematic review and meta-analysis of randomized controlled trials

DEFF Research Database (Denmark)

Uhrbrand, Anders; Stenager, Egon; Pedersen, Martin Sloth

2015-01-01

. Results In PD intensive exercise therapy (RT, ET and OITM) is feasible and safe. There is strong evidence that RT can improve muscle strength in PD, which is underlined by the meta-analysis (g′ = 0.54 [95%CI 0.22;0.86]). There is moderate evidence that ET can improve cardio-respiratory fitness in PD. RT...

Clinical Significance of Resistin Expression in Osteoarthritis: A Meta-Analysis

Directory of Open Access Journals (Sweden)

Xiao-Chuan Li

2014-01-01

Full Text Available Background. The objective of this study was to conduct a systematic review of literature evaluating human resistin expression as a diagnostic factor in osteoarthritis development and to quantify the overall diagnostic effect. Method. Relevant studies were identified and evaluated for quality through multiple search strategies. Studies analyzing resistin expression in the development of OA were eligible for inclusion. Data from eligible studies were extracted and included into the meta-analysis using a random-effects model. Results. Four case-control studies consisting of a total of 375 OA patients and 214 controls as well as three sex-stratified analyses composed of 53 males and 104 females were incorporated into our meta-analysis. Our results revealed that resistin levels were significantly higher in male OA subjects and OA patients overall. Country-stratified analysis yielded significantly different estimates in resistin levels between male OA subjects and female OA subjects in the Canadian subgroup but not among the French and USA subgroups. Based on the resistin levels in OA cases and controls, resistin levels were heightened in OA patients in the Dutch population. Conclusion. These results support the hypothesis that high expression of resistin represents a significant and reproducible marker of poor progression in OA patients, especially in males.

Chronic subdural hematoma: a systematic review and meta-analysis of surgical procedures.

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Liu, Weiming; Bakker, Nicolaas A; Groen, Rob J M

2014-09-01

In this paper the authors systematically evaluate the results of different surgical procedures for chronic subdural hematoma (CSDH). The MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and other databases were scrutinized according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) statement, after which only randomized controlled trials (RCTs) and quasi-RCTs were included. At least 2 different neurosurgical procedures in the management of chronic subdural hematoma (CSDH) had to be evaluated. Included studies were assessed for the risk of bias. Recurrence rates, complications, and outcome including mortality were taken as outcome measures. Statistical heterogeneity in each meta-analysis was assessed using the T(2) (tau-squared), I(2), and chi-square tests. The DerSimonian-Laird method was used to calculate the summary estimates using the fixed-effect model in meta-analysis. Of the 297 studies identified, 19 RCTs were included. Of them, 7 studies evaluated the use of postoperative drainage, of which the meta-analysis showed a pooled OR of 0.36 (95% CI 0.21-0.60; p < 0.001) in favor of drainage. Four studies compared twist drill and bur hole procedures. No significant differences between the 2 methods were present, but heterogeneity was considered to be significant. Three studies directly compared the use of irrigation before drainage. A fixed-effects meta-analysis showed a pooled OR of 0.49 (95% CI 0.21-1.14; p = 0.10) in favor of irrigation. Two studies evaluated postoperative posture. The available data did not reveal a significant advantage in favor of the postoperative supine posture. Regarding positioning of the catheter used for drainage, it was shown that a frontal catheter led to a better outcome. One study compared duration of drainage, showing that 48 hours of drainage was as effective as 96 hours of drainage. Postoperative drainage has the advantage of reducing recurrence without increasing complications

Meta-analysis on the efficacy of foot-and-mouth disease emergency vaccination

DEFF Research Database (Denmark)

Hisham Beshara Halasa, Tariq; Boklund, Anette; Cox, S.

2012-01-01

The objectives of this study were to provide a summary quantification of the efficacy of FMD emergency vaccination based on a systematic review and a meta-analysis of available literature, and to further discuss the suitability of this review and meta-analysis to summarize and further interpret...... of clinical signs including FMD lesions and fever, while the virological protection parameter was estimated based on the outcome of laboratory tests that were used to diagnose FMD infection. A meta-analysis relative risk was calculated per protection parameter. Results of the meta-analyses were examined using...... vaccine. Fortunately, no significant bias that would alter the conclusions was encountered in the analysis. Meta-analysis showed to be a useful tool to summarize literature results from a systematic review of the efficacy of foot and mouth disease emergency vaccination....

An Updated Meta-Analysis of Risk of Multiple Sclerosis following Infectious Mononucleosis

Science.gov (United States)

Handel, Adam E.; Williamson, Alexander J.; Disanto, Giulio; Handunnetthi, Lahiru; Giovannoni, Gavin; Ramagopalan, Sreeram V.

2010-01-01

Background Multiple sclerosis (MS) appears to develop in genetically susceptible individuals as a result of environmental exposures. Epstein-Barr virus (EBV) infection is an almost universal finding among individuals with MS. Symptomatic EBV infection as manifested by infectious mononucleosis (IM) has been shown in a previous meta-analysis to be associated with the risk of MS, however a number of much larger studies have since been published. Methods/Principal Findings We performed a Medline search to identify articles published since the original meta-analysis investigating MS risk following IM. A total of 18 articles were included in this study, including 19390 MS patients and 16007 controls. We calculated the relative risk of MS following IM using a generic inverse variance with random effects model. This showed that the risk of MS was strongly associated with IM (relative risk (RR) 2.17; 95% confidence interval 1.97–2.39; pmononucleosis significantly increases the risk of multiple sclerosis. Future work should focus on the mechanism of this association and interaction with other risk factors. PMID:20824132

An updated meta-analysis of risk of multiple sclerosis following infectious mononucleosis.

Directory of Open Access Journals (Sweden)

Adam E Handel

2010-09-01

Full Text Available Multiple sclerosis (MS appears to develop in genetically susceptible individuals as a result of environmental exposures. Epstein-Barr virus (EBV infection is an almost universal finding among individuals with MS. Symptomatic EBV infection as manifested by infectious mononucleosis (IM has been shown in a previous meta-analysis to be associated with the risk of MS, however a number of much larger studies have since been published.We performed a Medline search to identify articles published since the original meta-analysis investigating MS risk following IM. A total of 18 articles were included in this study, including 19390 MS patients and 16007 controls. We calculated the relative risk of MS following IM using a generic inverse variance with random effects model. This showed that the risk of MS was strongly associated with IM (relative risk (RR 2.17; 95% confidence interval 1.97-2.39; p<10(-54.Our results establish firmly that a history of infectious mononucleosis significantly increases the risk of multiple sclerosis. Future work should focus on the mechanism of this association and interaction with other risk factors.

[Ganciclovir therapy for congenital cytomegalovirus infection in newborn infants: a meta analysis].

Science.gov (United States)

Hu, Jin-Tao; Chen, Ping-Yang; Xie, Zong-De; Dang, Xi-Qiang; Wang, Tao; He, Xiao-Ri; Li, Wen; Bo, Tao

2010-01-01

To evaluate the efficacy and safety of ganciclovir therapy for congenital cytomegalovirus (CMV) infection in newborn infants. The randomized controlled trials (RCTs) and quasi-RCTs on ganciclovir therapy for congenital CMV were reviewed in the following electronic databases: PubMed (January 1988 to January 2009), EMbase (January 1988 to January 2009), the Cochrane library (Issue 3, 2003 and Issue 1, 2009), the Chinese Journals Full-text Database (January 1994 to January 2009), the Chinese Biological Medical Disc (January 1994 to January 2009) and the Chinese Medical Current Contents (January 1994 to January 2009). Quality assessment, data extraction, and meta analysis were performed. Ten papers were included. Meta analysis showed that the ganciclovir therapy increased the improvement rate (91.4% vs 34.0%; pCMV infection indexes to become negative in more patients (87.6% vs 15.3%; pCMV infection indexes becoming negative, and decrease incidence of hearing disturbance, with few side effects, in newborn infants with CMV infection. However the supporting evidence is not strong due to few trials and more high-quality research is needed.

Effect of Whey Supplementation on Circulating C-Reactive Protein: A Meta-Analysis of Randomized Controlled Trials

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Zhou, Ling-Mei; Xu, Jia-Ying; Rao, Chun-Ping; Han, Shufen; Wan, Zhongxiao; Qin, Li-Qiang

2015-01-01

Whey supplementation is beneficial for human health, possibly by reducing the circulating C-reactive protein (CRP) level, a sensitive marker of inflammation. Thus, a meta-analysis of randomized controlled trials was conducted to evaluate their relationship. A systematic literature search was conducted in July, 2014, to identify eligible studies. Either a fixed-effects model or a random-effects model was used to calculate pooled effects. The meta-analysis results of nine trials showed a slight, but no significant, reduction of 0.42 mg/L (95% CI −0.96, 0.13) in CRP level with the supplementation of whey protein and its derivates. Relatively high heterogeneity across studies was observed. Subgroup analyses showed that whey significantly lowered CRP by 0.72 mg/L (95% CI −0.97, −0.47) among trials with a daily whey dose ≥20 g/day and by 0.67 mg/L (95% CI −1.21, −0.14) among trials with baseline CRP ≥3 mg/L. Meta-regression analysis revealed that the baseline CRP level was a potential effect modifier of whey supplementation in reducing CRP. In conclusion, our meta-analysis did not find sufficient evidence that whey and its derivates elicited a beneficial effect in reducing circulating CRP. However, they may significantly reduce CRP among participants with highly supplemental doses or increased baseline CRP levels. PMID:25671415

Sleep and mental disorders: A meta-analysis of polysomnographic research.

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Baglioni, Chiara; Nanovska, Svetoslava; Regen, Wolfram; Spiegelhalder, Kai; Feige, Bernd; Nissen, Christoph; Reynolds, Charles F; Riemann, Dieter

2016-09-01

Investigating sleep in mental disorders has the potential to reveal both disorder-specific and transdiagnostic psychophysiological mechanisms. This meta-analysis aimed at determining the polysomnographic (PSG) characteristics of several mental disorders. Relevant studies were searched through standard strategies. Controlled PSG studies evaluating sleep in affective, anxiety, eating, pervasive developmental, borderline and antisocial personality disorders, attention-deficit-hyperactivity disorder (ADHD), and schizophrenia were included. PSG variables of sleep continuity, depth, and architecture, as well as rapid-eye movement (REM) sleep were considered. Calculations were performed with the "Comprehensive Meta-Analysis" and "R" software. Using random effects modeling, for each disorder and each variable, a separate meta-analysis was conducted if at least 3 studies were available for calculation of effect sizes as standardized means (Hedges' g). Sources of variability, that is, sex, age, and mental disorders comorbidity, were evaluated in subgroup analyses. Sleep alterations were evidenced in all disorders, with the exception of ADHD and seasonal affective disorders. Sleep continuity problems were observed in most mental disorders. Sleep depth and REM pressure alterations were associated with affective, anxiety, autism and schizophrenia disorders. Comorbidity was associated with enhanced REM sleep pressure and more inhibition of sleep depth. No sleep parameter was exclusively altered in 1 condition; however, no 2 conditions shared the same PSG profile. Sleep continuity disturbances imply a transdiagnostic imbalance in the arousal system likely representing a basic dimension of mental health. Sleep depth and REM variables might play a key role in psychiatric comorbidity processes. Constellations of sleep alterations may define distinct disorders better than alterations in 1 single variable. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Joint attention in Down syndrome: A meta-analysis.

Science.gov (United States)

Hahn, Laura J; Loveall, Susan J; Savoy, Madison T; Neumann, Allie M; Ikuta, Toshikazu

2018-07-01

Some studies have indicated that joint attention may be a relative strength in Down syndrome (DS), but other studies have not. To conduct a meta-analysis of joint attention in DS to more conclusively determine if this is a relative strength or weakness when compared to children with typical development (TD), developmental disabilities (DD), and autism spectrum disorder (ASD). Journal articles published before September 13, 2016, were identified by using the search terms "Down syndrome" and "joint attention" or "coordinating attention". Identified studies were reviewed and coded for inclusion criteria, descriptive information, and outcome variables. Eleven studies (553 participants) met inclusion criteria. Children with DS showed similar joint attention as TD children and higher joint attention than children with DD and ASD. Meta-regression revealed a significant association between age and joint attention effect sizes in the DS vs. TD contrast. Joint attention appears to not be a weakness for children with DS, but may be commensurate with developmental level. Joint attention may be a relative strength in comparison to other skills associated with the DS behavioral phenotype. Early interventions for children with DS may benefit from leveraging joint attention skills. Copyright © 2018 Elsevier Ltd. All rights reserved.

Systematic meta-analysis on association of human papilloma virus and oral cancer.

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Chaitanya, Nallan C S K; Allam, Neeharika Satya Jyothi; Gandhi Babu, D B; Waghray, Shefali; Badam, R K; Lavanya, Reddy

2016-01-01

Oral cancer is a disease with complex etiology. There is a strong evidence for the role of smoking, alcohol, genetic susceptibility, and indications that DNA viruses could also be involved in oral cancer. Recognized initially as sexually transmitted agent, human papilloma virus (HPV) is now considered a human carcinogen. Papilloma viruses are epitheliotropic viruses. A strong association of cervical cancer has been implicated with high-risk HPV16 and HPV18 infections, establishing the viral pathogenesis of the carcinoma. The etiopathogenesis is still unclear referring mainly to conflicting evidences in the detection of such viruses in oral carcinoma in spite of few studies suggesting their positive correlation. This systematic meta-analysis aimed to provide evidence-based analysis of literature relating oral cancer and HPV, along with identification of reliable diagnostic methodology for identifying HPV in oral and oropharyngeal cancer. A systematic review was performed using PubMed (from the year 1995 to 2015), Medline, Cochrane, ScienceDirect, and the Internet search. Reviewed literature included randomized control trials, cross sectional and cohort studies. Pooled data were analyzed by calculating relative risk and odds ratios (ORs), using a binary random-effects model. Out of 1497 cases, 588 patients were positive for HPV DNA, detected by various methods. About 39.27% of case samples were positive for HPV DNA. The calculated OR was 2.82 and 95% confidence interval, which showed significantly an increased risk of HPV among case group when compared to that of controls. The present meta-analysis suggests a potentially significant casual relation between HPV and oral and oropharyngeal cancers.

Meta-analysis: Problems with Russian Publications.

Science.gov (United States)

Verbitskaya, E V

2015-01-01

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

Psychotherapy for chronic major depression and dysthymia: A meta analysis.

NARCIS (Netherlands)

Cuijpers, P.; Straten, van A.; Schuurmans, J.; Oppen, van P.C.; Hollon, S.D.; Andersson, G.

2009-01-01

Abstract Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic

Meta-Analysis for Sociology – A Measure-Driven Approach

Science.gov (United States)

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

2013-01-01

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

Body mass index and age at natural menopause: a meta-analysis.

Science.gov (United States)

Tao, Xingyong; Jiang, Anran; Yin, Liping; Li, Yingchun; Tao, Fangbiao; Hu, Huaqing

2015-04-01

There is no universal consensus on the relationship between body mass index (BMI) and age at natural menopause (ANM). The primary bias was confounding by cigarette smoking because smoking was a strong confounding factor related to lower BMI and earlier menopause. This meta-analysis was conducted to estimate the effect of BMI on ANM. Medline and EMBASE databases were searched for relevant studies up to December 2013. Studies were selected for analysis based on certain inclusion and exclusion criteria. Hazard ratios (HRs) with 95% CI were extracted to assess the association between BMI and early ANM. Nine studies were selected for this meta-analysis. The HR of early ANM was 1.08 (95% CI, 1.03-1.14; P < 0.01) in underweight women compared with women of normal BMI. Compared with women of normal BMI, overweight women (HR, 0.93; 95% CI, 0.91-0.96; P < 0.001) and obese women (HR, 0.95; 95% CI, 0.79-1.15; P = 0.59) were associated with late ANM. In addition, the HRs of early ANM in overweight and obese women were 0.92 (95% CI, 0.90-0.94; P < 0.001) and 0.88 (95% CI, 0.82-0.95; P < 0.001), respectively, compared with underweight women. A separate meta-analysis indicated that the results (HR, 0.85; 95% CI, 0.81-0.90; P < 0.001) changed markedly in the comparison of obese versus normal-weight women in studies that controlled for smoking. The results of our study indicate that increased BMI modestly associates with later ANM. The relationship between BMI and ANM needs further clarification in well-designed studies, especially studies well-controlled for smoking status.

How acute total sleep loss affects the attending brain: a meta-analysis of neuroimaging studies.

Science.gov (United States)

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

2015-02-01

Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. © 2015 Associated Professional Sleep Societies, LLC.

An innovative and comprehensive technique to evaluate different measures of medication adherence: The network meta-analysis.

Science.gov (United States)

Tonin, Fernanda S; Wiecek, Elyssa; Torres-Robles, Andrea; Pontarolo, Roberto; Benrimoj, Shalom Charlie I; Fernandez-Llimos, Fernando; Garcia-Cardenas, Victoria

2018-05-19

Poor medication adherence is associated with adverse health outcomes and higher costs of care. However, inconsistencies in the assessment of adherence are found in the literature. To evaluate the effect of different measures of adherence in the comparative effectiveness of complex interventions to enhance patients' adherence to prescribed medications. A systematic review with network meta-analysis was performed. Electronic searches for relevant pairwise meta-analysis including trials of interventions that aimed to improve medication adherence were performed in PubMed. Data extraction was conducted with eligible trials evaluating short-period adherence follow-up (until 3 months) using any measure of adherence: self-report, pill count, or MEMS (medication event monitoring system). To standardize the results obtained with these different measures, an overall composite measure and an objective composite measure were also calculated. Network meta-analyses for each measure of adherence were built. Rank order and surface under the cumulative ranking curve analyses (SUCRA) were performed. Ninety-one trials were included in the network meta-analyses. The five network meta-analyses demonstrated robustness and reliability. Results obtained for all measures of adherence were similar across them and to both composite measures. For both composite measures, interventions comprising economic + technical components were the best option (90% of probability in SUCRA analysis) with statistical superiority against almost all other interventions and against standard care (odds ratio with 95% credibility interval ranging from 0.09 to 0.25 [0.02, 0.98]). The use of network meta-analysis was reliable to compare different measures of adherence of complex interventions in short-periods follow-up. Analyses with longer follow-up periods are needed to confirm these results. Different measures of adherence produced similar results. The use of composite measures revealed reliable alternatives

Sex differences in nicotine intravenous self-administration: A meta-analytic review.

Science.gov (United States)

Flores, Rodolfo J; Uribe, Kevin P; Swalve, Natashia; O'Dell, Laura E

2017-11-21

This report reflects a meta-analysis that systematically reviewed the literature on intravenous self-administration (IVSA) of nicotine in female and male rats. The goal was to determine if sex differences in nicotine IVSA exist, estimate the magnitude of the effect, and identify potential moderators of the relationship between sex differences and nicotine consumption. Extensive search procedures identified 20 studies that met the inclusion criteria of employing both female and male rats in nicotine IVSA procedures. The meta-analysis was conducted on effect size values that were calculated from mean total intake or nicotine deliveries using the Hedges' unbiased g u statistic. A random effects analysis revealed that overall females self-administered more nicotine than males (weighted g u =0.18, 95% CI [0.003, 0.34]). Subsequent moderator variable analyses revealed that certain procedural conditions influenced the magnitude of sex differences in nicotine IVSA. Specifically, higher reinforcement requirements (>FR1) and extended-access sessions (23h) were associated with greater nicotine IVSA in females versus males. Females also displayed higher nicotine intake than males when the experiment included a light cue that signaled nicotine delivery. Sex differences were not influenced by the diurnal phase of testing, dose of nicotine, or prior operant training. Overall, the results revealed that female rats display higher levels of nicotine IVSA than males, suggesting that the strong reinforcing effects of nicotine promote tobacco use in women. Copyright © 2017 Elsevier Inc. All rights reserved.

Mortality and cancer morbidity among cement production workers: a meta-analysis.

Science.gov (United States)

Donato, Francesca; Garzaro, Giacomo; Pira, Enrico; Boffetta, Paolo

2016-11-01

To analyze overall and cause-specific mortality, especially from cancer, among cement production workers. Results from some epidemiological studies suggested an increased risk of overall mortality and of stomach cancer associated with employment in the cement production, but the presence of a hazard and, if present, the magnitude of a risk have not been precisely quantified. We conducted a systematic review and meta-analysis of data on mortality from all causes, cardiovascular or respiratory diseases, and cancer among cement workers. The literature search in PubMed and Scopus up to February 2016 and with appropriate keywords on mortality among cement workers revealed 188 articles which were screened. A total of 117 articles were reviewed in full text and 12 articles, referring to 11 study populations, were found to be relevant and of sufficient quality for further analysis. Meta-analyses were performed using a random-effects model. Eight cohort studies, one proportionate mortality study, and two case-control studies were identified. The summary RRs were 0.89 [95 % confidence interval (CI) 0.76-1.01] for all-cause mortality, 0.94 (95 %, CI 0.80-1.08) for cancer mortality, 1.07 (95 % CI 0.79-1.35) for lung cancer mortality, and 0.93 (95 % CI 0.70-1.17) for stomach cancer mortality, respectively. Significant heterogeneity in results was observed among studies. The present meta-analysis does not provide evidence of increased risk of overall mortality, as well as cancer, cardiovascular or respiratory mortality in relation to employment in cement production.

Prognostic value of long noncoding RNA ZFAS1 in various carcinomas: a meta-analysis.

Science.gov (United States)

Dong, Dan; Mu, Zhongyi; Wang, Wei; Xin, Na; Song, Xiaowen; Shao, Yue; Zhao, Chenghai

2017-10-13

A number of studies have revealed that zinc finger antisense 1 (ZFAS1), a long noncoding RNA (lncRNA), is aberrantly regulated in various cancers, and high ZFAS1 expression is associated with poor prognosis and increased risk of lymph node metastasis (LNM). This meta-analysis was conducted to identify the potential value of ZFAS1 as a biomarker for cancer prognosis. We searched electronic database PubMed, Web of Science, and China Wanfang Data (up to June 1, 2017) to collect all relevant studies and explore the association of ZFAS1 expression with overall survival (OS) and LNM. The results showed that cancer patients with high ZFAS1 expression had a worse OS than those with low ZFAS1 expression (HR: 1.94, 95% confidence interval [CI]: 1.41-2.47, P analysis revealed that high ZFAS1 expression was significantly related to high incidence of LNM in subgroups of sample size more than 88 (OR: 3.16, 95% CI: 2.06-4.86, P value and publication year did not result in the inter-study heterogeneity. In conclusion, the present meta-analysis demonstrates that high ZFAS1 expression may potentially serve as a reliable biomarker for poor clinical outcome in various cancers.

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

Directory of Open Access Journals (Sweden)

Schumacher Martin

2008-05-01

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

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

Science.gov (United States)

Berhan, Asres; Berhan, Yifru; Yizengaw, Desalegn

2013-11-01

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

Psychotherapy for chronic major depression and dysthymia: A meta analysis

NARCIS (Netherlands)

Cuijpers, P.; van Straten, A.; Schuurmans, J.; van Oppen, P.C.; Hollon, S.D.; Andersson, G.

2010-01-01

Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic depression and

Psychotherapy for chronic major depression and dysthymia: A meta analysis.

NARCIS (Netherlands)

Cuijpers, P.; van Straten, A.; Schuurmans, J.; van Oppen, P.C.; Hollon, S.D.; Andersson, G.

2009-01-01

Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic depression and

Does chocolate reduce blood pressure? A meta-analysis.

Science.gov (United States)

Ried, Karin; Sullivan, Thomas; Fakler, Peter; Frank, Oliver R; Stocks, Nigel P

2010-06-28

Dark chocolate and flavanol-rich cocoa products have attracted interest as an alternative treatment option for hypertension, a known risk factor for cardiovascular disease. Previous meta-analyses concluded that cocoa-rich foods may reduce blood pressure. Recently, several additional trials have been conducted with conflicting results. Our study summarises current evidence on the effect of flavanol-rich cocoa products on blood pressure in hypertensive and normotensive individuals. We searched Medline, Cochrane and international trial registries between 1955 and 2009 for randomised controlled trials investigating the effect of cocoa as food or drink compared with placebo on systolic and diastolic blood pressure (SBP/DBP) for a minimum duration of 2 weeks. We conducted random effects meta-analysis of all studies fitting the inclusion criteria, as well as subgroup analysis by baseline blood pressure (hypertensive/normotensive). Meta-regression analysis explored the association between type of treatment, dosage, duration or baseline blood pressure and blood pressure outcome. Statistical significance was set at P chocolate compared with control (mean BP change +/- SE: SBP: -3.2 +/- 1.9 mmHg, P = 0.001; DBP: -2.0 +/- 1.3 mmHg, P = 0.003). However, subgroup meta-analysis was significant only for the hypertensive or prehypertensive subgroups (SBP: -5.0 +/- 3.0 mmHg; P = 0.0009; DBP: -2.7 +/- 2.2 mm Hg, P = 0.01), while BP was not significantly reduced in the normotensive subgroups (SBP: -1.6 +/- 2.3 mmHg, P = 0.17; DBP: -1.3 +/- 1.6 mmHg, P = 0.12). Nine trials used chocolate containing 50% to 70% cocoa compared with white chocolate or other cocoa-free controls, while six trials compared high- with low-flavanol cocoa products. Daily flavanol dosages ranged from 30 mg to 1000 mg in the active treatment groups, and interventions ran for 2 to 18 weeks. Meta-regression analysis found study design and type of control to be borderline significant but possibly indirect predictors

The Effects of Choice on Intrinsic Motivation and Related Outcomes: A Meta-Analysis of Research Findings

Science.gov (United States)

Patall, Erika A.; Cooper, Harris; Robinson, Jorgianne Civey

2008-01-01

A meta-analysis of 41 studies examined the effect of choice on intrinsic motivation and related outcomes in a variety of settings with both child and adult samples. Results indicated that providing choice enhanced intrinsic motivation, effort, task performance, and perceived competence, among other outcomes. Moderator tests revealed the effect…

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

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P.A. Lovatto

2007-07-01

Full Text Available Este texto descreve os princípios básicos de sistematização com enfoque em meta-análise. É apresentado o estado da arte da meta-análise, recuperando informações de sua evolução e metodologias básicas para sua realização. São descritos seus antecedentes históricos, os limites das abordagens clássicas de revisão de literatura, as bases conceituais, os objetivos e justificativas. É indicada uma metodologia geral para realização da meta-análise. São apresentados os critérios para a definição dos objetivos. São descritos os procedimentos de sistematização das informações e gestão de base bibliográfica de dados destinada aos estudos meta-analíticos (seleção, codificação, filtragem de dados. São apresentadas as análises mais comuns (gráfica, ponderações, a escolha do modelo estatístico (um fator explicativo qualitativo, um efeito qualitativo ou quantitativo, os fatores de interferência, os procedimentos pós-analíticos (variações residuais, heterogeneidade entre resultados. Em síntese, este texto mostra que a meta-análise é superior às formas tradicionais de revisão de literatura por estimar com maior precisão os efeitos dos tratamentos, ajustando-os para a heterogeneidade experimental. No entanto, a meta-análise exige os efeitos na sistematização e análise dos resultados da pesquisa.This text describes a basic approach of systematization with focus on meta-analysis. It is presented the art state of the meta-analysis, recovering information of its evolution and basic methodologies for its accomplishment. In this text are described the historical antecedents of meta-analysis, the limits of the classic approaches of literature review, the conceptual bases and the objectives. It is indicated a general methodology for meta-analysis procedures. The criteria for the definition of the objectives are presented. The procedures of the systematization and management of bibliographical data base selected to

Effect of melatonin on nocturnal blood pressure: meta-analysis of randomized controlled trials

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Laudon M

2011-09-01

Full Text Available Ehud Grossman1,4, Moshe Laudon2, Nava Zisapel2,31Department of Internal Medicine D and Hypertension Unit, The Chaim Sheba Medical Center, Tel-Hashomer, Israel; 2Neurim Pharmaceuticals Ltd, Tel Aviv, Israel and 3Department of Neurobiology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel; 4Sackler School of Medicine, Tel Aviv University, Tel Aviv, IsraelBackground: Patients with nocturnal hypertension are at higher risk for cardiovascular complications such as myocardial infarction and cerebrovascular insult. Published studies inconsistently reported decreases in nocturnal blood pressure with melatonin.Methods: A meta-analysis of the efficacy and safety of exogenous melatonin in ameliorating nocturnal blood pressure was performed using a random effects model of all studies fitting the inclusion criteria, with subgroup analysis of fast-release versus controlled-release preparations.Results: Seven trials (three of controlled-release and four of fast-release melatonin with 221 participants were included. Meta-analysis of all seven studies did not reveal significant effects of melatonin versus placebo on nocturnal blood pressure. However, subgroup analysis revealed that controlled-release melatonin significantly reduced nocturnal blood pressure whereas fast-release melatonin had no effect. Systolic blood pressure decreased significantly with controlled-release melatonin (-6.1 mmHg; 95% confidence interval [CI] -10.7 to -1.5; P = 0.009 but not fast-release melatonin (-0.3 mmHg; 95% CI -5.9 to 5.30; P = 0.92. Diastolic blood pressure also decreased significantly with controlled-release melatonin (-3.5 mmHg; 95% CI -6.1 to -0.9; P = 0.009 but not fast-release melatonin (-0.2 mmHg; 95% CI -3.8 to 3.3; P = 0.89. No safety concerns were raised.Conclusion: Add-on controlled-release melatonin to antihypertensive therapy is effective and safe in ameliorating nocturnal hypertension, whereas fast-release melatonin is ineffective. It is necessary

Antioxidant therapy for patients with chronic pancreatitis: A systematic review and meta-analysis.

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Zhou, Dongkai; Wang, Weilin; Cheng, Xiaofei; Wei, Jianfeng; Zheng, Shusen

2015-08-01

Chronic pancreatitis is a progressive, inflammatory disease of pancreas characterized by significant abdominal pain, malabsorption, and diabetes mellitus. Antioxidant therapy has been proposed as an effective treatment for painful chronic pancreatitis. We performed a meta-analysis of trials in which antioxidant therapy was compared with placebo in chronic pancreatitis. We searched six databases to identify relevant trials. Results are expressed as risk ratio (RR) or standardized mean difference (SMD) with accompanying 95% confidence intervals (CI). The meta-analysis was performed with the fixed-effects model or random-effects model according to heterogeneity. Eight studies including 573 patients met the inclusion criteria. A meta-analysis of these studies revealed that the intervention of antioxidants was associated with a significant increase in patients with pain relief (RR, 2.15; 95% CI, 1.72-2.69; P chronic pancreatitis patients (SMD: -0.41; 95% CI: -0.83 to -0.10; P = 0.0005). Additionally, antioxidants may cause some adverse reactions (RR, 4.22; 95% CI: 2.17-8.20; P pathophysiology of chronic pancreatitis, and administration of antioxidants to patients with painful chronic pancreatitis is effective in relieving pain. Antioxidant supplements may be advocated as one medical therapy for chronic pancreatitis patients with low antioxidant capacity in their blood. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Prognostic role of platelet to lymphocyte ratio in non-small cell lung cancers: A meta-analysis including 3,720 patients.

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Zhao, Qing-Tao; Yuan, Zheng; Zhang, Hua; Zhang, Xiao-Peng; Wang, Hui-En; Wang, Zhi-Kang; Duan, Guo-Chen

2016-07-01

Platelet to lymphocyte ratio (PLR) was recently reported as a useful index in predicting the prognosis of lung cancer. However, the prognostic role of PLR in lung cancer remains controversial. The aim of this study was to evaluate the association between PLR and clinical outcome of lung cancer patients through a meta-analysis. Relevant literatures were retrieved from PubMed, Ovid, the Cochrane Library and Web of Science databases. Meta-analysis was performed using hazard ratio (HR) and 95% confidence intervals (CIs) as effect measures. A total of 5,314 patients from 13 studies were finally enrolled in the meta-analysis. The summary results showed that elevated PLR predicted poorer overall survival (OS) (HR: 1.526, 95%CI: 1.268-1.836, p analysis revealed that increased PLR was also associated with poor OS in NSCLC treated by surgical resection (HR: 1.884, 95%CI: 1.308-2.714, P 160 (HR: 1.842, 95%CI: 1.523-2.228, P  0.05) in patients with small cell lung cancer (SCLC).This meta-analysis result suggested that elevated PLR might be a predicative factor of poor prognosis for NSCLC patients. © 2016 UICC.

The Relation of Racial Identity, Ethnic Identity, and Racial Socialization to Discrimination-Distress: A Meta-Analysis of Black Americans

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Lee, Debbiesiu L.; Ahn, Soyeon

2013-01-01

This meta-analysis synthesized the results of 27 studies examining the relations of racial identity, ethnic identity, and racial socialization to discrimination-distress for Black Americans. The purpose was to uncover which constructs connected to racial identity, ethnic identity, and racial socialization most strongly correlate with racial…

Neuroimaging after mild traumatic brain injury: Review and meta-analysis

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Cyrus Eierud

2014-01-01

Full Text Available This paper broadly reviews the study of mild traumatic brain injury (mTBI, across the spectrum of neuroimaging modalities. Among the range of imaging methods, however, magnetic resonance imaging (MRI is unique in its applicability to studying both structure and function. Thus we additionally performed meta-analyses of MRI results to examine 1 the issue of anatomical variability and consistency for functional MRI (fMRI findings, 2 the analogous issue of anatomical consistency for white-matter findings, and 3 the importance of accounting for the time post injury in diffusion weighted imaging reports. As we discuss, the human neuroimaging literature consists of both small and large studies spanning acute to chronic time points that have examined both structural and functional changes with mTBI, using virtually every available medical imaging modality. Two key commonalities have been used across the majority of imaging studies. The first is the comparison between mTBI and control populations. The second is the attempt to link imaging results with neuropsychological assessments. Our fMRI meta-analysis demonstrates a frontal vulnerability to mTBI, demonstrated by decreased signal in prefrontal cortex compared to controls. This vulnerability is further highlighted by examining the frequency of reported mTBI white matter anisotropy, in which we show a strong anterior-to-posterior gradient (with anterior regions being more frequently reported in mTBI. Our final DTI meta-analysis examines a debated topic arising from inconsistent anisotropy findings across studies. Our results support the hypothesis that acute mTBI is associated with elevated anisotropy values and chronic mTBI complaints are correlated with depressed anisotropy. Thus, this review and set of meta-analyses demonstrate several important points about the ongoing use of neuroimaging to understand the functional and structural changes that occur throughout the time course of mTBI recovery

SLEEP AND MENTAL DISORDERS: A META-ANALYSIS OF POLYSOMNOGRAPHIC RESEARCH

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Baglioni, Chiara; Nanovska, Svetoslava; Regen, Wolfram; Spiegelhalder, Kai; Feige, Bernd; Nissen, Christoph; Reynolds, Charles F.; Riemann, Dieter

2016-01-01

Investigating sleep in mental disorders has the potential to reveal both disorder-specific and transdiagnostic psychophysiological mechanisms. This meta-analysis aimed at determining the polysomnographic (PSG) characteristics of several mental disorders. Relevant studies were searched through standard strategies. Controlled PSG studies evaluating sleep in affective, anxiety, eating, pervasive developmental, borderline and antisocial personality disorders, ADHD, and schizophrenia were included. PSG variables of sleep continuity, depth, and architecture, as well as rapid-eye movement (REM) sleep were considered. Calculations were performed with the “Comprehensive Meta-Analysis” and “R” softwares. Using random effects modeling, for each disorder and each variable, a separate meta-analysis was conducted if at least 3 studies were available for calculation of effect sizes as standardized means (Hedges’g). Sources of variability, i.e., sex, age, and mental disorders comorbidity, were evaluated in subgroup analyses. Sleep alterations were evidenced in all disorders, with the exception of ADHD and seasonal affective disorders. Sleep continuity problems were observed in most mental disorders. Sleep depth and REM pressure alterations were associated with affective, anxiety, autism and schizophrenia disorders. Comorbidity was associated with enhanced REM sleep pressure and more inhibition of sleep depth. No sleep parameter was exclusively altered in one condition; however, no two conditions shared the same PSG profile. Sleep continuity disturbances imply a transdiagnostic imbalance in the arousal system likely representing a basic dimension of mental health. Sleep depth and REM variables might play a key role in psychiatric comorbidity processes. Constellations of sleep alterations may define distinct disorders better than alterations in one single variable. PMID:27416139

Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression

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Cai, Xianlei; Wang, Chen; Yu, Wanqi; Fan, Wenjie; Wang, Shan; Shen, Ning; Wu, Pengcheng; Li, Xiuyang; Wang, Fudi

2016-01-01

The objective of this study was to investigate the associations between selenium exposure and cancer risk. We identified 69 studies and applied meta-analysis, meta-regression and dose-response analysis to obtain available evidence. The results indicated that high selenium exposure had a protective effect on cancer risk (pooled OR = 0.78; 95%CI: 0.73–0.83). The results of linear and nonlinear dose-response analysis indicated that high serum/plasma selenium and toenail selenium had the efficacy on cancer prevention. However, we did not find a protective efficacy of selenium supplement. High selenium exposure may have different effects on specific types of cancer. It decreased the risk of breast cancer, lung cancer, esophageal cancer, gastric cancer, and prostate cancer, but it was not associated with colorectal cancer, bladder cancer, and skin cancer. PMID:26786590

The correlation between apparent diffusion coefficient and tumor cellularity in patients: a meta-analysis.

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Chen, Lihua; Liu, Min; Bao, Jing; Xia, Yunbao; Zhang, Jiuquan; Zhang, Lin; Huang, Xuequan; Wang, Jian

2013-01-01

To perform a meta-analysis exploring the correlation between the apparent diffusion coefficient (ADC) and tumor cellularity in patients. We searched medical and scientific literature databases for studies discussing the correlation between the ADC and tumor cellularity in patients. Only studies that were published in English or Chinese prior to November 2012 were considered for inclusion. Summary correlation coefficient (r) values were extracted from each study, and 95% confidence intervals (CIs) were calculated. Sensitivity and subgroup analyses were performed to investigate potential heterogeneity. Of 189 studies, 28 were included in the meta-analysis, comprising 729 patients. The pooled r for all studies was -0.57 (95% CI: -0.62, -0.52), indicating notable heterogeneity (Pcorrelation between the ADC and cellularity for brain tumors. There was no notable evidence of publication bias. There is a strong negative correlation between the ADC and tumor cellularity in patients, particularly in the brain. However, larger, prospective studies are warranted to validate these findings in other cancer types.

A Meta-Analysis of the Relationship between Testicular Microlithiasis and Incidence of Testicular Cancer.

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Wang, Tao; Liu, LuHao; Luo, JinTai; Liu, TaiSheng; Wei, AnYang

2015-04-29

There are many recent observational studies on testicular microlithiasis (TM) and risk of testicular cancer. Whether TM increases the risk of testicular cancer is still inconclusive. The objective of this updated meta-analysis was to synthesize evidence from clinical observational studies that evaluated the association between TM and testicular cancer. We identified eligible studies by searching the PubMed, Embase and Cochrane Library before March 2014. Adjusted relative risks (RR) with 95% confidence interval (CI) were calculated using random-or fixed-model. A total of 14 studies involving 35,578 participants were included in the meta-analysis. On the basis of the Newcastle Ottawa Scale systematic review, eleven studies were identified as relatively high-quality. TM was strong association with an increased incidence of testicular cancer (RR = 12.70, 95% CI: 8.18-19.71, P testicular cancer. More researches are warranted to clarify an understanding of the association between TM and risk of testicular cancer.

Memory and Obstructive Sleep Apnea: A Meta-Analysis

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Wallace, Anna; Bucks, Romola S.

2013-01-01

Study Objectives: To examine episodic memory performance in individuals with obstructive sleep apnea (OSA). Design Meta-analysis was used to synthesize results from individual studies examining the impact of OSA on episodic memory performance. The performance of individuals with OSA was compared to healthy controls or normative data. Participants Forty-two studies were included, comprising 2,294 adults with untreated OSA and 1,364 healthy controls. Studies that recorded information about participants at baseline prior to treatment interventions were included in the analysis. Measurements Participants were assessed with tasks that included a measure of episodic memory: immediate recall, delayed recall, learning, and/or recognition memory. Results: The results of the meta-analyses provide evidence that individuals with OSA are significantly impaired when compared to healthy controls on verbal episodic memory (immediate recall, delayed recall, learning, and recognition) and visuo-spatial episodic memory (immediate and delayed recall), but not visual immediate recall or visuo-spatial learning. When patients were compared to norms, negative effects of OSA were found only in verbal immediate and delayed recall. Conclusions: This meta-analysis contributes to understanding of the nature of episodic memory deficits in individuals with OSA. Impairments to episodic memory are likely to affect the daily functioning of individuals with OSA. Citation Wallace A; Bucks RS. Memory and obstructive sleep apnea: a meta-analysis. SLEEP 2013;36(2):203-220. PMID:23372268

Caffeine ingestion enhances Wingate performance: a meta-analysis.

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Grgic, Jozo

2018-03-01

The positive effects of caffeine ingestion on aerobic performance are well-established; however, recent findings are suggesting that caffeine ingestion might also enhance components of anaerobic performance. A commonly used test of anaerobic performance and power output is the 30-second Wingate test. Several studies explored the effects of caffeine ingestion on Wingate performance, with equivocal findings. To elucidate this topic, this paper aims to determine the effects of caffeine ingestion on Wingate performance using meta-analytic statistical techniques. Following a search through PubMed/MEDLINE, Scopus, and SportDiscus ® , 16 studies were found meeting the inclusion criteria (pooled number of participants = 246). Random-effects meta-analysis of standardized mean differences (SMD) for peak power output and mean power output was performed. Study quality was assessed using the modified version of the PEDro checklist. Results of the meta-analysis indicated a significant difference (p = .005) between the placebo and caffeine trials on mean power output with SMD values of small magnitude (0.18; 95% confidence interval: 0.05, 0.31; +3%). The meta-analysis performed for peak power output indicated a significant difference (p = .006) between the placebo and caffeine trials (SMD = 0.27; 95% confidence interval: 0.08, 0.47 [moderate magnitude]; +4%). The results from the PEDro checklist indicated that, in general, studies are of good and excellent methodological quality. This meta-analysis adds on to the current body of evidence showing that caffeine ingestion can also enhance components of anaerobic performance. The results presented herein may be helpful for developing more efficient evidence-based recommendations regarding caffeine supplementation.

Systematic review and meta-analysis in cardiac surgery: a primer.

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Yanagawa, Bobby; Tam, Derrick Y; Mazine, Amine; Tricco, Andrea C

2018-03-01

The purpose of this article is to review the strengths and weaknesses of systematic reviews and meta-analyses to inform our current understanding of cardiac surgery. A systematic review and meta-analysis of a focused topic can provide a quantitative estimate for the effect of a treatment intervention or exposure. In cardiac surgery, observational studies and small, single-center prospective trials provide most of the clinical outcomes that form the evidence base for patient management and guideline recommendations. As such, meta-analyses can be particularly valuable in synthesizing the literature for a particular focused surgical question. Since the year 2000, there are over 800 meta-analysis-related publications in our field. There are some limitations to this technique, including clinical, methodological and statistical heterogeneity, among other challenges. Despite these caveats, results of meta-analyses have been useful in forming treatment recommendations or in providing guidance in the design of future clinical trials. There is a growing number of meta-analyses in the field of cardiac surgery. Knowledge translation via meta-analyses will continue to guide and inform cardiac surgical practice and our practice guidelines.

Recurrence rates following I-131 therapy of differentiated thyroid carcinoma: results of meta-analysis

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Obaldo, J.M.

1990-01-01

To examine the efficacy of I-131 therapy in decreasing recurrence rates after surgery for differentiated thyroid carcinoma, a research tool called meta-analysis was used. Data were pooled from five published studies which evaluated recurrences following at least sub-total thyroidectomy with or without I-131 ablation of remnants. Of 1332 patients managed surgically only 202 (15%) developed recurrences compared to 36 of 339 (11%) treated with radioiodine. This difference was statistically significant at p<.05. When a separate analysis of only those studies which directly compared the two modes of management was conducted, recurrence rates for patients treated by surgery alone was higher at 18% (185 of 1034) compared with those who had subsequent I-131 therapy with a rate of 9% (27 of 297). This difference was again significant at p <.001. This meta-analysis strongly suggests that the use of I-131 for ablation of post-surgical thyroid remnants significantly reduces recurrence rates in patients with differentiated thyroid carcinoma. (Auth.). 34 refs., 1 tab.; 1 fig

Empirical Comparison of Publication Bias Tests in Meta-Analysis.

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Lin, Lifeng; Chu, Haitao; Murad, Mohammad Hassan; Hong, Chuan; Qu, Zhiyong; Cole, Stephen R; Chen, Yong

2018-04-16

Decision makers rely on meta-analytic estimates to trade off benefits and harms. Publication bias impairs the validity and generalizability of such estimates. The performance of various statistical tests for publication bias has been largely compared using simulation studies and has not been systematically evaluated in empirical data. This study compares seven commonly used publication bias tests (i.e., Begg's rank test, trim-and-fill, Egger's, Tang's, Macaskill's, Deeks', and Peters' regression tests) based on 28,655 meta-analyses available in the Cochrane Library. Egger's regression test detected publication bias more frequently than other tests (15.7% in meta-analyses of binary outcomes and 13.5% in meta-analyses of non-binary outcomes). The proportion of statistically significant publication bias tests was greater for larger meta-analyses, especially for Begg's rank test and the trim-and-fill method. The agreement among Tang's, Macaskill's, Deeks', and Peters' regression tests for binary outcomes was moderately strong (most κ's were around 0.6). Tang's and Deeks' tests had fairly similar performance (κ > 0.9). The agreement among Begg's rank test, the trim-and-fill method, and Egger's regression test was weak or moderate (κ < 0.5). Given the relatively low agreement between many publication bias tests, meta-analysts should not rely on a single test and may apply multiple tests with various assumptions. Non-statistical approaches to evaluating publication bias (e.g., searching clinical trials registries, records of drug approving agencies, and scientific conference proceedings) remain essential.

When Is Hub Gene Selection Better than Standard Meta-Analysis?

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Langfelder, Peter; Mischel, Paul S.; Horvath, Steve

2013-01-01

Since hub nodes have been found to play important roles in many networks, highly connected hub genes are expected to play an important role in biology as well. However, the empirical evidence remains ambiguous. An open question is whether (or when) hub gene selection leads to more meaningful gene lists than a standard statistical analysis based on significance testing when analyzing genomic data sets (e.g., gene expression or DNA methylation data). Here we address this question for the special case when multiple genomic data sets are available. This is of great practical importance since for many research questions multiple data sets are publicly available. In this case, the data analyst can decide between a standard statistical approach (e.g., based on meta-analysis) and a co-expression network analysis approach that selects intramodular hubs in consensus modules. We assess the performance of these two types of approaches according to two criteria. The first criterion evaluates the biological insights gained and is relevant in basic research. The second criterion evaluates the validation success (reproducibility) in independent data sets and often applies in clinical diagnostic or prognostic applications. We compare meta-analysis with consensus network analysis based on weighted correlation network analysis (WGCNA) in three comprehensive and unbiased empirical studies: (1) Finding genes predictive of lung cancer survival, (2) finding methylation markers related to age, and (3) finding mouse genes related to total cholesterol. The results demonstrate that intramodular hub gene status with respect to consensus modules is more useful than a meta-analysis p-value when identifying biologically meaningful gene lists (reflecting criterion 1). However, standard meta-analysis methods perform as good as (if not better than) a consensus network approach in terms of validation success (criterion 2). The article also reports a comparison of meta-analysis techniques applied to

When is hub gene selection better than standard meta-analysis?

Directory of Open Access Journals (Sweden)

Peter Langfelder

Full Text Available Since hub nodes have been found to play important roles in many networks, highly connected hub genes are expected to play an important role in biology as well. However, the empirical evidence remains ambiguous. An open question is whether (or when hub gene selection leads to more meaningful gene lists than a standard statistical analysis based on significance testing when analyzing genomic data sets (e.g., gene expression or DNA methylation data. Here we address this question for the special case when multiple genomic data sets are available. This is of great practical importance since for many research questions multiple data sets are publicly available. In this case, the data analyst can decide between a standard statistical approach (e.g., based on meta-analysis and a co-expression network analysis approach that selects intramodular hubs in consensus modules. We assess the performance of these two types of approaches according to two criteria. The first criterion evaluates the biological insights gained and is relevant in basic research. The second criterion evaluates the validation success (reproducibility in independent data sets and often applies in clinical diagnostic or prognostic applications. We compare meta-analysis with consensus network analysis based on weighted correlation network analysis (WGCNA in three comprehensive and unbiased empirical studies: (1 Finding genes predictive of lung cancer survival, (2 finding methylation markers related to age, and (3 finding mouse genes related to total cholesterol. The results demonstrate that intramodular hub gene status with respect to consensus modules is more useful than a meta-analysis p-value when identifying biologically meaningful gene lists (reflecting criterion 1. However, standard meta-analysis methods perform as good as (if not better than a consensus network approach in terms of validation success (criterion 2. The article also reports a comparison of meta-analysis techniques

When is hub gene selection better than standard meta-analysis?

Science.gov (United States)

Langfelder, Peter; Mischel, Paul S; Horvath, Steve

2013-01-01

Since hub nodes have been found to play important roles in many networks, highly connected hub genes are expected to play an important role in biology as well. However, the empirical evidence remains ambiguous. An open question is whether (or when) hub gene selection leads to more meaningful gene lists than a standard statistical analysis based on significance testing when analyzing genomic data sets (e.g., gene expression or DNA methylation data). Here we address this question for the special case when multiple genomic data sets are available. This is of great practical importance since for many research questions multiple data sets are publicly available. In this case, the data analyst can decide between a standard statistical approach (e.g., based on meta-analysis) and a co-expression network analysis approach that selects intramodular hubs in consensus modules. We assess the performance of these two types of approaches according to two criteria. The first criterion evaluates the biological insights gained and is relevant in basic research. The second criterion evaluates the validation success (reproducibility) in independent data sets and often applies in clinical diagnostic or prognostic applications. We compare meta-analysis with consensus network analysis based on weighted correlation network analysis (WGCNA) in three comprehensive and unbiased empirical studies: (1) Finding genes predictive of lung cancer survival, (2) finding methylation markers related to age, and (3) finding mouse genes related to total cholesterol. The results demonstrate that intramodular hub gene status with respect to consensus modules is more useful than a meta-analysis p-value when identifying biologically meaningful gene lists (reflecting criterion 1). However, standard meta-analysis methods perform as good as (if not better than) a consensus network approach in terms of validation success (criterion 2). The article also reports a comparison of meta-analysis techniques applied to

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

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

2018-04-01

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

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

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Shaked, Michal; Yirmiya, Nurit

2004-01-01

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

Sensitivity analysis for publication bias in meta-analysis of diagnostic studies for a continuous biomarker.

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Hattori, Satoshi; Zhou, Xiao-Hua

2018-02-10

Publication bias is one of the most important issues in meta-analysis. For standard meta-analyses to examine intervention effects, the funnel plot and the trim-and-fill method are simple and widely used techniques for assessing and adjusting for the influence of publication bias, respectively. However, their use may be subjective and can then produce misleading insights. To make a more objective inference for publication bias, various sensitivity analysis methods have been proposed, including the Copas selection model. For meta-analysis of diagnostic studies evaluating a continuous biomarker, the summary receiver operating characteristic (sROC) curve is a very useful method in the presence of heterogeneous cutoff values. To our best knowledge, no methods are available for evaluation of influence of publication bias on estimation of the sROC curve. In this paper, we introduce a Copas-type selection model for meta-analysis of diagnostic studies and propose a sensitivity analysis method for publication bias. Our method enables us to assess the influence of publication bias on the estimation of the sROC curve and then judge whether the result of the meta-analysis is sufficiently confident or should be interpreted with much caution. We illustrate our proposed method with real data. Copyright © 2017 John Wiley & Sons, Ltd.

Cholelithiasis, cholecystectomy and risk of hepatocellular carcinoma: A meta-analysis

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Lingyun Guo

2014-01-01

Full Text Available Available evidence of the relationship between cholelithiasis, cholecystectomy, and risk of liver cancer and hence we conducted a meta-analysis to investigate the relationships. PubMed, EMBASE, and ISI Web of Knowledge were searched to identify all published cohort studies and case-control studies that evaluated the relationships of cholelithiasis, cholecystectomy and risk of liver cancer and single-cohort studies which evaluated the incidence of liver cancer among patients who understood cholecystectomy (up to February 2013. Comprehensive meta-analysis software was used for meta-analysis. A total of 11 observational studies (six cohort studies and five case-control studies were included in this meta-analysis. The result from meta-analysis showed that cholecystectomy (risk ratio [RR]: 1.59, 95% confidence interval [CI]: 1.01-2.51, I2 = 72% and cholecystolithiasis (RR: 5.40, 95% CI: 3.69-7.89, I2 = 93% was associated with more liver cancer, especially for intrahepatic cholangiocarcinoma (ICC (cholecystectomy: RR: 3.51, 95% CI: 1.84-6.71, I2 = 26%; cholecystolithiasis: RR: 11.06, 95% CI: 6.99-17.52, I2 = 0%. The pooled standardized incidence rates (SIR of liver cancer in patients who understood cholecystectomy showed cholecystectomy might increase the incidence of liver cancer (SIR: 1.57, 95% CI: 1.13-2.20, I2 = 15%. Based on the results of the meta-analysis, cholecystectomy and cholecystolithiasis seemed to be involved in the development of liver cancer, especially for ICC. However, most available studies were case-control studies and short-term cohort studies, so the future studies should more long-term cohort studies should be well-conducted to evaluate the long-term relationship.

Cell-Free DNA in Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis.

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Spindler, Karen-Lise G; Boysen, Anders K; Pallisgård, Niels; Johansen, Julia S; Tabernero, Josep; Sørensen, Morten M; Jensen, Benny V; Hansen, Torben F; Sefrioui, David; Andersen, Rikke F; Brandslund, Ivan; Jakobsen, Anders

2017-09-01

Circulating DNA can be detected and quantified in the blood of cancer patients and used for detection of tumor-specific genetic alterations. The clinical utility has been intensively investigated for the past 10 years. The majority of reports focus on analyzing the clinical potential of tumor-specific mutations, whereas the use of total cell-free DNA (cfDNA) quantification is somehow controversial and sparsely described in the literature, but holds important clinical information in itself. The purpose of the present report was to present a systematic review and meta-analysis of the prognostic value of total cfDNA in patients with metastatic colorectal cancer (mCRC) treated with chemotherapy. In addition, we report on the overall performance of cfDNA as source for KRAS mutation detection. A systematic literature search of PubMed and Embase was performed by two independent investigators. Eligibility criteria were (a) total cfDNA analysis, (b) mCRC, and (c) prognostic value during palliative treatment. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed, and meta-analysis applied on both aggregate data extraction and individual patients' data. Ten eligible cohorts were identified, including a total of 1,076 patients. Seven studies used quantitative polymerase chain reaction methods, two BEAMing [beads, emulsification, amplification, and magnetics] technology, and one study digital droplet polymerase chain reaction. The baseline levels of cfDNA was similar in the presented studies, and all studies reported a clear prognostic value in favor of patients with lowest levels of baseline cfDNA. A meta-analysis revealed a combined estimate of favorable overall survival hazard ratio (HR) in patients with levels below the median cfDNA (HR = 2.39, 95% confidence interval 2.03-2.82, p  meta-analysis. Reliable prognostic markers could help to guide patients and treating physicians regarding the relevance and choice of

Biomechanical Differences of Foot-Strike Patterns During Running: A Systematic Review With Meta-analysis.

Science.gov (United States)

Almeida, Matheus O; Davis, Irene S; Lopes, Alexandre D

2015-10-01

Systematic review with meta-analysis. To determine the biomechanical differences between foot-strike patterns used when running. Strike patterns during running have received attention in the recent literature due to their potential mechanical differences and associated injury risks. Electronic databases (MEDLINE, Embase, LILACS, SciELO, and SPORTDiscus) were searched through July 2014. Studies (cross-sectional, case-control, prospective, and retrospective) comparing the biomechanical characteristics of foot-strike patterns during running in distance runners at least 18 years of age were included in this review. Two independent reviewers evaluated the risk of bias. A meta-analysis with a random-effects model was used to combine the data from the included studies. Sixteen studies were included in the final analysis. In the meta-analyses of kinematic variables, significant differences between forefoot and rearfoot strikers were found for foot and knee angle at initial contact and knee flexion range of motion. A forefoot-strike pattern resulted in a plantar-flexed ankle position and a more flexed knee position, compared to a dorsiflexed ankle position and a more extended knee position for the rearfoot strikers, at initial contact with the ground. In the comparison of rearfoot and midfoot strikers, midfoot strikers demonstrated greater ankle dorsiflexion range of motion and decreased knee flexion range of motion compared to rearfoot strikers. For kinetic variables, the meta-analysis revealed that rearfoot strikers had higher vertical loading rates compared to forefoot strikers. There are differences in kinematic and kinetic characteristics between foot-strike patterns when running. Clinicians should be aware of these characteristics to help in the management of running injuries and advice on training.

Exercise and Bone Density: Meta-Analysis

National Research Council Canada - National Science Library

Kelley, George A; Sharpe-Kelley, Kristi

2007-01-01

.... Since no meta-analysis had existed using individual patient data (IPD) to examine the effects of exercise on BMD, our second two-year period of funding was devoted to examining the feasibility...

Meta-analysis in plant pathology: synthesizing research results.

Science.gov (United States)

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

2004-09-01

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

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

Science.gov (United States)

Mahdi, Hassan Saleh

2018-01-01

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

Geographical and Ethnic Distributions of the MTHFR C677T, A1298C and MTRR A66G Gene Polymorphisms in Chinese Populations: A Meta-Analysis.

Directory of Open Access Journals (Sweden)

Xingmin Wang

Full Text Available The geographical and ethnic distributions of the polymorphic methylenetetrahydrofolate reductase (MTHFR mutations (C677T and A1298C and methionine synthase reductase (MTRR mutation (A66G remain heterogeneous in China. The goal of this study was to estimate the pooled frequencies of the alleles and associated genotypes of these gene polymorphisms among healthy populations in Mainland China.We systematically reviewed published epidemiological studies on the distributions of 3 genetic variants in Chinese healthy populations living in Mainland China through a meta-analysis. The relevant electronic databases were searched. All of the raw data of the eligible citations were extracted. The frequency estimates were stratified by geography, ethnicity and sex.Sixty-six studies were identified with a total of 92277 study participants. The meta-analysis revealed that the frequencies of the MTHFR C677T, A1298C, and MTRR A66G gene polymorphisms varied significantly between different ethnic groups and along geographical gradients. The frequencies of the 677T allele and 677TT genotype increased along the southern-central-northern direction across Mainland China (all Pvalues≤0.001. The frequencies of the 1298C, 1298CC, 66G and 66GG genotypes decreased along the south-central-north direction across the country (all Pvalues≤0.001.Our meta-analysis strongly indicates significant geographical and ethnic variations in the frequencies of the C677T, A1298C, and A66G gene polymorphisms in the folate metabolism pathway among Chinese populations.

Hydropower externalities: a meta analysis

NARCIS (Netherlands)

Mattmann, M.; Logar, I.; Brouwer, R.

2016-01-01

This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to

Anagrelide compared with hydroxyurea in essential thrombocythemia: a meta-analysis.

Science.gov (United States)

Samuelson, Bethany; Chai-Adisaksopha, Chatree; Garcia, David

2015-11-01

Cytoreductive therapy, with or without low-dose aspirin, is the mainstay of thrombotic risk reduction in patients with essential thrombocythemia (ET), but the optimal choice of agent remains unclear. The aim of this study was to meta-analyze currently available data comparing anagrelide to hydroxyurea for reduction of rates of thrombosis, bleeding and death among patients with ET. A literature search for randomized, controlled trials comparing anagrelide to hydroxyurea among patients with ET revealed two published studies. Statistical analysis was performed using fixed effects meta-analysis. Rates of thrombosis were similar between patients treated with hydroxyurea vs anagrelide (RR 0.86, 95 % CI 0.64-1.16). Rates of major bleeding were lower in patients treated with hydroxyurea (RR 0.37, 95 % CI 0.18-0.75). Rates of progression to acute myeloid leukemia were not statistically different (RR 1.50, 95 % CI 0.43-5.29). The composite of thrombosis, major bleeding and death favored hydroxyurea (RR 0.78, 95 % CI 0.63-0.97). In conclusion, our analysis supports use of hydroxyurea as a first-line cytoreductive agent for patients with ET, based largely on decreased rates of major bleeding. Anagrelide appears to be equally effective for protection against thrombotic events and may be an appropriate alternative for patients who are intolerant of hydroxyurea.

MADAM - An open source meta-analysis toolbox for R and Bioconductor

Directory of Open Access Journals (Sweden)

Graber Armin

2010-03-01

Full Text Available Abstract Background Meta-analysis is a major theme in biomedical research. In the present paper we introduce a package for R and Bioconductor that provides useful tools for performing this type of work. One idea behind the development of MADAM was that many meta-analysis methods, which are available in R, are not able to use the capacities of parallel computing yet. In this first version, we implemented one meta-analysis method in such a parallel manner. Additionally, we provide tools for combining the results from a set of methods in an ensemble approach. Functionality for visualization of results is also provided. Results The presented package enables the carrying out of meta-analysis either by providing functions directly or by wrapping them to existing implementations. Overall, five different meta-analysis methods are now usable through MADAM, along with another three methods for combining the corresponding results. Visualizing the results is eased by three included functions. For developing and testing meta-analysis methods, a mock up data generator is integrated. Conclusions The use of MADAM enables a user to focus on one package, in turn enabling them to work with the same data types across a set of methods. By making use of the snow package, MADAM can be made compatible with an existing parallel computing infrastructure. MADAM is open source and freely available within CRAN http://cran.r-project.org.

A Meta-analysis on Resting State High-frequency Heart Rate Variability in Bulimia Nervosa.

Science.gov (United States)

Peschel, Stephanie K V; Feeling, Nicole R; Vögele, Claus; Kaess, Michael; Thayer, Julian F; Koenig, Julian

2016-09-01

Autonomic nervous system function is altered in eating disorders. We aimed to quantify differences in resting state vagal activity, indexed by high-frequency heart rate variability comparing patients with bulimia nervosa (BN) and healthy controls. A systematic search of the literature to identify studies eligible for inclusion and meta-analytical methods were applied. Meta-regression was used to identify potential covariates. Eight studies reporting measures of resting high-frequency heart rate variability in individuals with BN (n = 137) and controls (n = 190) were included. Random-effects meta-analysis revealed a sizeable main effect (Z = 2.22, p = .03; Hedge's g = 0.52, 95% CI [0.06;0.98]) indicating higher resting state vagal activity in individuals with BN. Meta-regression showed that body mass index and medication intake are significant covariates. Findings suggest higher vagal activity in BN at rest, particularly in unmedicated samples with lower body mass index. Potential mechanisms underlying these findings and implications for routine clinical care are discussed. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.

Infant search and object permanence: a meta-analysis of the A-not-B error.

Science.gov (United States)

Wellman, H M; Cross, D; Bartsch, K

1987-01-01

Research on Piaget's stage 4 object concept has failed to reveal a clear or consistent pattern of results. Piaget found that 8-12-month-old infants would make perserverative errors; his explanation for this phenomenon was that the infant's concept of the object was contextually dependent on his or her actions. Some studies designed to test Piaget's explanation have replicated Piaget's basic finding, yet many have found no preference for the A location or the B location or an actual preference for the B location. More recently, researchers have attempted to uncover the causes for these results concerning the A-not-B error. Again, however, different studies have yielded different results, and qualitative reviews have failed to yield a consistent explanation for the results of the individual studies. This state of affairs suggests that the phenomenon may simply be too complex to be captured by individual studies varying 1 factor at a time and by reviews based on similar qualitative considerations. Therefore, the current investigation undertook a meta-analysis, a synthesis capturing the quantitative information across the now sizable number of studies. We entered several important factors into the meta-analysis, including the effects of age, the number of A trials, the length of delay between hiding and search, the number of locations, the distances between locations, and the distinctive visual properties of the hiding arrays. Of these, the analysis consistently indicated that age, delay, and number of hiding locations strongly influence infants' search. The pattern of specific findings also yielded new information about infant search. A general characterization of the results is that, at every age, both above-chance and below-chance performance was observed. That is, at each age at least 1 combination of delay and number of locations yielded above-chance A-not-B errors or significant perseverative search. At the same time, at each age at least 1 alternative

Assessing the Determinants of Renewable Electricity Acceptance Integrating Meta-Analysis Regression and a Local Comprehensive Survey

Directory of Open Access Journals (Sweden)

Simona Bigerna

2015-08-01

Full Text Available In dealing with renewable electricity (RE, individuals are involved both as end-consumers on the demand side and as stakeholders (citizens in the local production process on the supply side. Empirical evidence shows that in many countries, consumers are willing to pay a significant amount to facilitate adoption of RE. By contrast, environmental externalities are often the cause of strong opposition to RE adoption if local communities are involved as stakeholders in wind, solar or biomass investment projects. Looking at the literature on willingness to pay and on willingness to accept, we have investigated RE acceptance mechanisms. First, we have used the meta-analysis to assess the major determinants of RE acceptance on both demand and supply sides. Meta-analysis has provided some insights useful for managing field research on an onshore wind farm enlargement project located in the Umbria region. Meta-analysis and survey results confirm that the local community plays a central role in local RE acceptance. Furthermore, people who have previous experience with windmills require less compensation, or are willing to pay more, for RE development. Results suggest that these attributes should be included in future research to improve understanding of determinants of RE acceptance.

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

Science.gov (United States)

Ordano, Mariano; Ornelas, Juan Francisco

2004-08-01

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

Death and Disability in Patients with Sleep Apnea - A Meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Fonseca, Maria Inês Pires, E-mail: pinespines@gmail.com; Pereira, Telmo; Caseiro, Paulo [Instituto Politécnico de Coimbra - ESTESC - Departamento de Fisiologia Clínica, Coimbra (Portugal)

2015-01-15

Several studies have been attempting to ascertain the risks of Sleep Apnea Syndrome (SAS) and its morbidity and mortality. The main objective was to verify whether SAS increases the risk of death; the secondary objective was to evaluate its morbidity in relation to cardiovascular disease and the number of days hospitalized. A systematic review and a meta-analysis were performed of the published literature. The research focused on studies comparing the number of deaths in patients with untreated SAS and in patients with non-SAS. The meta-analysis was based on 13 articles, corresponding to a total of 13394 participants divided into two groups (non-SAS = 6631; SAS = 6763). The meta-analysis revealed a clear association of SAS with the occurrence of fatal events, where the presence of SAS corresponded to a 61% higher risk of total mortality (OR=1.61; CI: 1.43 - 1.81; p < 0.00001), while the risk of death from cardiac causes was 2.52 times higher in these patients (OR = 2.52; IC: 1.80 - 3.52; p < 0.00001). Similar results were obtained for mortality from other causes (OR = 1.68; CI: 1.08 - 2.61; p = 0.02). Resembling results were obtained in the remaining outcomes: non-fatal cardiovascular events were higher in the SAS group (OR = 2.46; IC: 1.80 - 3.36; p < 0.00001), the average number of days hospitalized was also higher in the SAS group (IV = 18.09; IC: 13.34 - 22.84; p < 0.00001). The results show that untreated SAS significantly increases the risk of death, cardiovascular events and the average number of days hospitalized.

Death and Disability in Patients with Sleep Apnea - A Meta-analysis

International Nuclear Information System (INIS)

Fonseca, Maria Inês Pires; Pereira, Telmo; Caseiro, Paulo

2015-01-01

Several studies have been attempting to ascertain the risks of Sleep Apnea Syndrome (SAS) and its morbidity and mortality. The main objective was to verify whether SAS increases the risk of death; the secondary objective was to evaluate its morbidity in relation to cardiovascular disease and the number of days hospitalized. A systematic review and a meta-analysis were performed of the published literature. The research focused on studies comparing the number of deaths in patients with untreated SAS and in patients with non-SAS. The meta-analysis was based on 13 articles, corresponding to a total of 13394 participants divided into two groups (non-SAS = 6631; SAS = 6763). The meta-analysis revealed a clear association of SAS with the occurrence of fatal events, where the presence of SAS corresponded to a 61% higher risk of total mortality (OR=1.61; CI: 1.43 - 1.81; p < 0.00001), while the risk of death from cardiac causes was 2.52 times higher in these patients (OR = 2.52; IC: 1.80 - 3.52; p < 0.00001). Similar results were obtained for mortality from other causes (OR = 1.68; CI: 1.08 - 2.61; p = 0.02). Resembling results were obtained in the remaining outcomes: non-fatal cardiovascular events were higher in the SAS group (OR = 2.46; IC: 1.80 - 3.36; p < 0.00001), the average number of days hospitalized was also higher in the SAS group (IV = 18.09; IC: 13.34 - 22.84; p < 0.00001). The results show that untreated SAS significantly increases the risk of death, cardiovascular events and the average number of days hospitalized

Likelihood ratio meta-analysis: New motivation and approach for an old method.

Science.gov (United States)

Dormuth, Colin R; Filion, Kristian B; Platt, Robert W

2016-03-01

A 95% confidence interval (CI) in an updated meta-analysis may not have the expected 95% coverage. If a meta-analysis is simply updated with additional data, then the resulting 95% CI will be wrong because it will not have accounted for the fact that the earlier meta-analysis failed or succeeded to exclude the null. This situation can be avoided by using the likelihood ratio (LR) as a measure of evidence that does not depend on type-1 error. We show how an LR-based approach, first advanced by Goodman, can be used in a meta-analysis to pool data from separate studies to quantitatively assess where the total evidence points. The method works by estimating the log-likelihood ratio (LogLR) function from each study. Those functions are then summed to obtain a combined function, which is then used to retrieve the total effect estimate, and a corresponding 'intrinsic' confidence interval. Using as illustrations the CAPRIE trial of clopidogrel versus aspirin in the prevention of ischemic events, and our own meta-analysis of higher potency statins and the risk of acute kidney injury, we show that the LR-based method yields the same point estimate as the traditional analysis, but with an intrinsic confidence interval that is appropriately wider than the traditional 95% CI. The LR-based method can be used to conduct both fixed effect and random effects meta-analyses, it can be applied to old and new meta-analyses alike, and results can be presented in a format that is familiar to a meta-analytic audience. Copyright © 2016 Elsevier Inc. All rights reserved.

Age, the psychological contract, and job attitudes : a meta-analysis

NARCIS (Netherlands)

Bal, P. Matthijs; de Lange, Annet H.; Jansen, Paul G. W.; van der Velde, Mandy E. G.

Age, the psychological contract, and job attitudes: a meta-analysis P.M. Bal, A H. De Lange, P.G.W Jansen Er M.E G Van der Velde, Gedrag en Organisatie, volume 23, March 2010, nr 1, pp 44-72. The meta-analysis investigated the relations between age and psychological contracts It was expected that

Association between the rs7574865 polymorphism of STAT4 and rheumatoid arthritis: a meta-analysis.

Science.gov (United States)

Lee, Young Ho; Woo, Jin-Hyun; Choi, Seong Jae; Ji, Jong Dae; Song, Gwan Gyu

2010-03-01

The aim of this study was to determine whether the rs7574865 polymorphism of STAT4 (signal transducers and activators of transcription 4) confers susceptibility to rheumatoid arthritis (RA) in populations with different ethnicities. A meta-analysis was conducted on the T allele of the STAT4 rs7574865 polymorphism in 15 studies containing 16,088 RA patients and 16,509 normal control subjects. Meta-analysis revealed an association between RA and the STAT4 rs7574865 T allele in all subjects (OR = 1.271, 95% CI = 1.197-1.350, P rs7574865 T allele was found to be significantly associated with RA in Europeans and Asians (OR = 1.300, 95% CI = 1.195-1.414, P rs7574865 polymorphism is associated with RA susceptibility in different ethnic groups, and that its prevalence is ethnicity dependent.

Sequential Stereotype Priming: A Meta-Analysis.

Science.gov (United States)

Kidder, Ciara K; White, Katherine R; Hinojos, Michelle R; Sandoval, Mayra; Crites, Stephen L

2017-08-01

Psychological interest in stereotype measurement has spanned nearly a century, with researchers adopting implicit measures in the 1980s to complement explicit measures. One of the most frequently used implicit measures of stereotypes is the sequential priming paradigm. The current meta-analysis examines stereotype priming, focusing specifically on this paradigm. To contribute to ongoing discussions regarding methodological rigor in social psychology, one primary goal was to identify methodological moderators of the stereotype priming effect-whether priming is due to a relation between the prime and target stimuli, the prime and target response, participant task, stereotype dimension, stimulus onset asynchrony (SOA), and stimuli type. Data from 39 studies yielded 87 individual effect sizes from 5,497 participants. Analyses revealed that stereotype priming is significantly moderated by the presence of prime-response relations, participant task, stereotype dimension, target stimulus type, SOA, and prime repetition. These results carry both practical and theoretical implications for future research on stereotype priming.

Rate of familial amyotrophic lateral sclerosis: a systematic review and meta-analysis.

LENUS (Irish Health Repository)

Byrne, Susan

2010-11-03

Background The population rate of familial amyotrophic lateral sclerosis (FALS) is frequently reported as 10%. However, a systematic review and meta-analysis of the true population based frequency of FALS has never been performed. Method A Medline literature review identified all original articles reporting a rate of FALS. Studies were grouped according to the type of data presented and examined for sources of case ascertainment. A systematic review and meta-analysis of reported rates of FALS was then conducted to facilitate comparison between studies and calculate a pooled rate of FALS. Results 38 papers reported a rate of FALS. Thirty-three papers were included in analysis and the rate of FALS for all studies was 4.6% (95% CI 3.9% to 5.5%). Restricting the analysis to prospective population based registry data revealed a rate of 5.1% (95% CI 4.1% to 6.1%). The incidence of FALS was lower in southern Europe. There was no correlation between rate of FALS and reported SOD1 mutation rates. Conclusion The rate of FALS among prospective population based registries is 5.1% (CI 4.1 to 6.1%), and not 10% as is often stated. Further detailed prospective population based studies of familial ALS are required to confirm this rate.

Rate of familial amyotrophic lateral sclerosis: a systematic review and meta-analysis.

LENUS (Irish Health Repository)

Byrne, Susan

2012-02-01

BACKGROUND: The population rate of familial amyotrophic lateral sclerosis (FALS) is frequently reported as 10%. However, a systematic review and meta-analysis of the true population based frequency of FALS has never been performed. METHOD: A Medline literature review identified all original articles reporting a rate of FALS. Studies were grouped according to the type of data presented and examined for sources of case ascertainment. A systematic review and meta-analysis of reported rates of FALS was then conducted to facilitate comparison between studies and calculate a pooled rate of FALS. RESULTS: 38 papers reported a rate of FALS. Thirty-three papers were included in analysis and the rate of FALS for all studies was 4.6% (95% CI 3.9% to 5.5%). Restricting the analysis to prospective population based registry data revealed a rate of 5.1% (95% CI 4.1% to 6.1%). The incidence of FALS was lower in southern Europe. There was no correlation between rate of FALS and reported SOD1 mutation rates. CONCLUSION: The rate of FALS among prospective population based registries is 5.1% (CI 4.1 to 6.1%), and not 10% as is often stated. Further detailed prospective population based studies of familial ALS are required to confirm this rate.

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

Science.gov (United States)

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

2014-07-01

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

A meta-analysis of perceptions of defeat and entrapment in depression, anxiety problems, posttraumatic stress disorder, and suicidality.

Science.gov (United States)

Siddaway, Andy P; Taylor, Peter J; Wood, Alex M; Schulz, Joerg

2015-09-15

There is a burgeoning literature examining perceptions of being defeated or trapped in different psychiatric disorders. The disorders most frequently examined to date are depression, anxiety problems, posttraumatic stress disorder (PTSD), and suicidality. To quantify the size and consistency of perceptions of defeat and entrapment in depression, anxiety problems, PTSD and suicidality, test for differences across psychiatric disorders, and examine potential moderators and publication bias. Random-effects meta-analyses based on Pearson's correlation coefficient r. Forty studies were included in the meta-analysis (n = 10,072). Perceptions of defeat and entrapment were strong (around r = 0.60) and similar in size across all four psychiatric disorders. Perceptions of defeat were particularly strong in depression (r = 0.73). There was no between-study heterogeneity; therefore moderator analyses were conducted in an exploratory fashion. There was no evidence of publication bias. Analyses were cross-sectional, which precludes establishing temporal precedence or causality. Some of the meta-analyses were based on relatively small numbers of effect sizes, which may limit their generalisability. Perceptions of defeat and entrapment are clinically important in depression, anxiety problems, PTSD, and suicidality. Similar-sized, strong relationships across four different psychiatric disorders could suggest that perceptions of defeat and entrapment are transdiagnostic constructs. The results suggest that clinicians and researchers need to become more aware of perceptions of defeat and entrapment. Copyright © 2015 Elsevier B.V. All rights reserved.

The Impact of Uncertainty on Investment. A Meta-Analysis

Energy Technology Data Exchange (ETDEWEB)

Koetse, M.J. [Department of Spatial Economics, Vrije Universiteit Amsterdam (Netherlands); De Groot, Henri L.F. [Tinbergen Institute, Amsterdam (Netherlands); Florax, R.J.G.M. [Department of Agricultural Economics, Purdue University, West Lafayette (United States)

2006-07-01

In this paper we perform a meta-analysis on empirical estimates of the impact between investment and uncertainty. Since the outcomes of primary studies are largely incomparable with respect to the magnitude of the effect, our analysis focuses on the direction and statistical significance of the relationship. The standard approach in this situation is to estimate an ordered probit model on a categorical estimate, defined in terms of the direction of the effect. The estimates are transformed into marginal effects, in order to represent the changes in the probability of finding a negative significant, insignificant, and positive significant estimate. Although a meta-analysis generally does not allow for inferences on the correctness of model specifications in primary studies, our results give clear directions for model building in empirical investment research. For example, not including factor prices in investment models may seriously affect the model outcomes. Furthermore, we find that Q models produce more negative significant estimates than other models do, ceteris paribus. The outcome of a study is also affected by the type of data used in a primary study. Although it is clear that meta-analysis cannot always give decisive insights into the explanations for the variation in empirical outcomes, our meta-analysis shows that we can explain to a large extent why empirical estimates of the investment uncertainty relationship differ.

A meta-analysis of cerebrovascular disease and hyperhomocysteinaemia

DEFF Research Database (Denmark)

Nielsen, G M; Tvedegaard, K C; Andersen, Niels Trolle

2000-01-01

Hyperhomocysteinaemia has been identified as a risk factor for stroke and cerebrovascular disease in several studies. To evaluate the evidence we performed a meta-analysis. We found 21 studies searching Medline from 1966-July 1999 using the key words homocysteine, homocystine and cerebrovascular...... was used. The reports on 8 cross-sectional and 4 longitudinal studies gave data on the mean and standard deviations of plasma or serum homocysteine for both cases and controls, and these studies were included in the meta-analysis. The results of the 5 excluded studies all pointed to a positive relationship...

The prevalence of food allergy: A meta-analysis

DEFF Research Database (Denmark)

Rona, Roberto J.; Keil, Thomas; Summers, Colin

2007-01-01

Background: There is uncertainty about the prevalence of food allergy in communities. Objective: To assess the prevalence of food allergy by performing a meta-analysis according to the method of assessment used. Methods: The foods assessed were cow's milk, hen's egg, peanut, fish, shellfish....... The meta-analysis included only original studies. They were stratified by age groups: infant/preschool, school children, and adults. Results: A total of 934 articles were identified, but only 51 were considered appropriate for inclusion. The prevalence of self-reported food allergy was very high compared...

Physical Readiness Training: A Meta-Analysis

National Research Council Canada - National Science Library

Vickers, Jr, Ross R

2007-01-01

.... This meta-analysis of available PRT studies (k = 3) indicated that (a) Fitness gains in the PRT program were equal to the gains in traditional fitness programs, and (b) the injury rate (i.e., hazard ratio...

Hydropower externalities: A meta-analysis

International Nuclear Information System (INIS)

Mattmann, Matteo; Logar, Ivana; Brouwer, Roy

2016-01-01

This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to quantify and explain the economic values for positive and negative hydropower externalities. Different meta-regression model specifications are used to test the robustness of significant determinants of non-market values, including different types of hydropower impacts. The explanatory and predictive power of the estimated models is relatively high. Whilst controlling for sample and study characteristics, we find significant evidence for public aversion towards deteriorations of landscape, vegetation and wildlife caused by hydropower projects. There is however only weak evidence of willingness to pay for mitigating these effects. The main positive externality of hydropower generation, the avoidance of greenhouse gas emission, positively influences welfare estimates when combined with the share of hydropower in national energy production. Sensitivity to scope is detected, but not linked to specific externalities or non-market valuation methods. - Highlights: • A global meta-analysis of valuation studies of hydropower externalities is presented. • Positive and negative externalities are distinguished. • Welfare losses due to environmental deteriorations outweigh gains of GHG reductions. • There is only weak evidence of public WTP for mitigating negative externalities. • The non-market values of hydropower externalities are sensitive to scope.

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

Science.gov (United States)

Furnham, A; Hayward, R

1997-09-01

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

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

Science.gov (United States)

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

2017-11-01

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

Correlates of perceived stigma for people living with epilepsy: A meta-analysis.

Science.gov (United States)

Shi, Ying; Wang, Shouqi; Ying, Jie; Zhang, Meiling; Liu, Pengcheng; Zhang, Huanhuan; Sun, Jiao

2017-05-01

Epilepsy, one of the most common, serious chronic neurological diseases, is accompanied by different levels of perceived stigma that affects people in almost all age groups. This stigma can negatively impact the physical and mental health of people living with epilepsy (PLWE). Good knowledge of perceived stigma for PLWE is important. In this study, we conducted a meta-analysis to identify the correlates of perceived stigma for PLWE. Studies on factors associated with perceived stigma for PLWE, including sociodemographic, psychosocial, and disease-related variables, were searched in PubMed, PsychINFO, EMBASE, and Web of Science. Nineteen variables (k>1) were included in the meta-analysis. For sociodemographic characteristics, findings revealed that the significant weighted mean correlation (R) for "residence" and "poor financial status" were 0.177 and 0.286, respectively. For disease-related characteristics, all variables of significance, including "seizure severity," "seizure frequency," "number of medicines," and "adverse event" (R ranging from 0.190 to 0.362), were positively correlated with perceived stigma. For psychosocial characteristics, "depression" and "anxiety" with R values of 0.414 and 0.369 were significantly associated with perceived stigma. In addition, "social support," "quality of life (QOLIE-31,89)," "knowledge," and "attitude," with R values ranging from -0.444 to -0.200 indicating negative correlation with perceived stigma. The current meta-analysis evaluated the correlates of perceived stigma for PLWE. Results can serve as a basis for policymakers and healthcare professionals for formulating health promotion and prevention strategies. Copyright © 2017 Elsevier Inc. All rights reserved.

Interventions to reduce stress in university students: a review and meta-analysis.

Science.gov (United States)

Regehr, Cheryl; Glancy, Dylan; Pitts, Annabel

2013-05-15

Recent research has revealed concerning rates of anxiety and depression among university students. Nevertheless, only a small percentage of these students receive treatment from university health services. Universities are thus challenged with instituting preventative programs that address student stress and reduce resultant anxiety and depression. A systematic review of the literature and meta-analysis was conducted to examine the effectiveness of interventions aimed at reducing stress in university students. Studies were eligible for inclusion if the assignment of study participants to experimental or control groups was by random allocation or parallel cohort design. Retrieved studies represented a variety of intervention approaches with students in a broad range of programs and disciplines. Twenty-four studies, involving 1431 students were included in the meta-analysis. Cognitive, behavioral and mindfulness interventions were associated with decreased symptoms of anxiety. Secondary outcomes included lower levels of depression and cortisol. Included studies were limited to those published in peer reviewed journals. These studies over-represent interventions with female students in Western countries. Studies on some types of interventions such as psycho-educational and arts based interventions did not have sufficient data for inclusion in the meta-analysis. This review provides evidence that cognitive, behavioral, and mindfulness interventions are effective in reducing stress in university students. Universities are encouraged to make such programs widely available to students. In addition however, future work should focus on developing stress reduction programs that attract male students and address their needs. Copyright © 2012 Elsevier B.V. All rights reserved.

Energy efficiency in Germany - a meta-analysis. Analysis and recommendations

International Nuclear Information System (INIS)

Bauernhansl, Thomas

2014-01-01

The Stuttgart Institute of energy efficiency in production compiled the first meta-analysis ''Energy Efficiency in Germany''.It provides facts and figures on the development atatus and knowledge level of energy efficiency in Germany. The study shows the contribution have been made by individual measures and the potentials which are known, but have not yet been lifted. For this meta-analysis more than 250 items available from research institutions, government departments, professional and industry associations have been identified with the main topic of energy efficiency and evaluated. It provides an overview of the status of development and is an important reference work for industry, associations and politics. [de

Prevalence of rapid eye movement sleep behavior disorder (RBD) in Parkinson's disease: a meta and meta-regression analysis.

Science.gov (United States)

Zhang, Xiaona; Sun, Xiaoxuan; Wang, Junhong; Tang, Liou; Xie, Anmu

2017-01-01

Rapid eye movement sleep behavior disorder (RBD) is thought to be one of the most frequent preceding symptoms of Parkinson's disease (PD). However, the prevalence of RBD in PD stated in the published studies is still inconsistent. We conducted a meta and meta-regression analysis in this paper to estimate the pooled prevalence. We searched the electronic databases of PubMed, ScienceDirect, EMBASE and EBSCO up to June 2016 for related articles. STATA 12.0 statistics software was used to calculate the available data from each research. The prevalence of RBD in PD patients in each study was combined to a pooled prevalence with a 95 % confidence interval (CI). Subgroup analysis and meta-regression analysis were performed to search for the causes of the heterogeneity. A total of 28 studies with 6869 PD cases were deemed eligible and included in our meta-analysis based on the inclusion and exclusion criteria. The pooled prevalence of RBD in PD was 42.3 % (95 % CI 37.4-47.1 %). In subgroup analysis and meta-regression analysis, we found that the important causes of heterogeneity were the diagnosis criteria of RBD and age of PD patients (P = 0.016, P = 0.019, respectively). The results indicate that nearly half of the PD patients are suffering from RBD. Older age and longer duration are risk factors for RBD in PD. We can use the minimal diagnosis criteria for RBD according to the International Classification of Sleep Disorders to diagnose RBD patients in our daily work if polysomnography is not necessary.

Diet influenced tooth erosion prevalence in children and adolescents: Results of a meta-analysis and meta-regression

NARCIS (Netherlands)

Salas, M.M.; Nascimento, G.G.; Vargas-Ferreira, F.; Tarquinio, S.B.; Huysmans, M.C.D.N.J.M.; Demarco, F.F.

2015-01-01

OBJECTIVE: The aim of the present study was to assess the influence of diet in tooth erosion presence in children and adolescents by meta-analysis and meta-regression. DATA: Two reviewers independently performed the selection process and the quality of studies was assessed. SOURCES: Studies

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

Science.gov (United States)

Kalaian, Sema A; Kasim, Rafa M

2017-12-01

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

Neurological Soft Signs in Schizophrenia: A Meta-analysis

Science.gov (United States)

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

2010-01-01

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

Meta-analysis of randomized clinical trials in the era of individual patient data sharing.

Science.gov (United States)

Kawahara, Takuya; Fukuda, Musashi; Oba, Koji; Sakamoto, Junichi; Buyse, Marc

2018-06-01

Individual patient data (IPD) meta-analysis is considered to be a gold standard when the results of several randomized trials are combined. Recent initiatives on sharing IPD from clinical trials offer unprecedented opportunities for using such data in IPD meta-analyses. First, we discuss the evidence generated and the benefits obtained by a long-established prospective IPD meta-analysis in early breast cancer. Next, we discuss a data-sharing system that has been adopted by several pharmaceutical sponsors. We review a number of retrospective IPD meta-analyses that have already been proposed using this data-sharing system. Finally, we discuss the role of data sharing in IPD meta-analysis in the future. Treatment effects can be more reliably estimated in both types of IPD meta-analyses than with summary statistics extracted from published papers. Specifically, with rich covariate information available on each patient, prognostic and predictive factors can be identified or confirmed. Also, when several endpoints are available, surrogate endpoints can be assessed statistically. Although there are difficulties in conducting, analyzing, and interpreting retrospective IPD meta-analysis utilizing the currently available data-sharing systems, data sharing will play an important role in IPD meta-analysis in the future.

GetReal in network meta-analysis : a review of the methodology

NARCIS (Netherlands)

Efthimiou, Orestis; Debray, Thomas P A; van Valkenhoef, Gert; Trelle, Sven; Panayidou, Klea; Moons, Karel G M; Reitsma, Johannes B.; Shang, Aijing; Salanti, Georgia

2016-01-01

Pairwise meta-analysis is an established statistical tool for synthesizing evidence from multiple trials, but it is informative only about the relative efficacy of two specific interventions. The usefulness of pairwise meta-analysis is thus limited in real-life medical practice, where many competing

Network meta-analysis-highly attractive but more methodological research is needed

NARCIS (Netherlands)

Li, Tianjing; Puhan, Milo A.; Vedula, Swaroop S.; Singh, Sonal; Dickersin, Kay; Cameron, Chris; Goodman, Steven N.; Mills, Edward; Musch, David; ter Riet, Gerben; Robinson, Karen; Schmid, Christopher; Song, Fujian; Thorlund, Kristian; Trikalinos, Thomas

2011-01-01

Network meta-analysis, in the context of a systematic review, is a meta-analysis in which multiple treatments (that is, three or more) are being compared using both direct comparisons of interventions within randomized controlled trials and indirect comparisons across trials based on a common

Updated Meta-Analysis of Learner Control within Educational Technology

Science.gov (United States)

Karich, Abbey C.; Burns, Matthew K.; Maki, Kathrin E.

2014-01-01

Giving a student control over their learning has theoretical and intuitive appeal, but its effects are neither powerful nor consistent in the empirical literature base. This meta-analysis updated previous meta-analytic research by Niemiec, Sikorski, and Walberg by studying the overall effectiveness of providing learner control within educational…

Racism as a determinant of health: a protocol for conducting a systematic review and meta-analysis

Science.gov (United States)

2013-01-01

Background Racism is increasingly recognized as a key determinant of health. A growing body of epidemiological evidence shows strong associations between self-reported racism and poor health outcomes across diverse minority groups in developed countries. While the relationship between racism and health has received increasing attention over the last two decades, a comprehensive meta-analysis focused on the health effects of racism has yet to be conducted. The aim of this review protocol is to provide a structure from which to conduct a systematic review and meta-analysis of studies that assess the relationship between racism and health. Methods This research will consist of a systematic review and meta-analysis. Studies will be considered for review if they are empirical studies reporting quantitative data on the association between racism and health for adults and/or children of all ages from any racial/ethnic/cultural groups. Outcome measures will include general health and well-being, physical health, mental health, healthcare use and health behaviors. Scientific databases (for example, Medline) will be searched using a comprehensive search strategy and reference lists will be manually searched for relevant studies. In addition, use of online search engines (for example, Google Scholar), key websites, and personal contact with experts will also be undertaken. Screening of search results and extraction of data from included studies will be independently conducted by at least two authors, including assessment of inter-rater reliability. Studies included in the review will be appraised for quality using tools tailored to each study design. Summary statistics of study characteristics and findings will be compiled and findings synthesized in a narrative summary as well as a meta-analysis. Discussion This review aims to examine associations between reported racism and health outcomes. This comprehensive and systematic review and meta-analysis of empirical research

Racism as a determinant of health: a protocol for conducting a systematic review and meta-analysis.

Science.gov (United States)

Paradies, Yin; Priest, Naomi; Ben, Jehonathan; Truong, Mandy; Gupta, Arpana; Pieterse, Alex; Kelaher, Margaret; Gee, Gilbert

2013-09-23

Racism is increasingly recognized as a key determinant of health. A growing body of epidemiological evidence shows strong associations between self-reported racism and poor health outcomes across diverse minority groups in developed countries. While the relationship between racism and health has received increasing attention over the last two decades, a comprehensive meta-analysis focused on the health effects of racism has yet to be conducted. The aim of this review protocol is to provide a structure from which to conduct a systematic review and meta-analysis of studies that assess the relationship between racism and health. This research will consist of a systematic review and meta-analysis. Studies will be considered for review if they are empirical studies reporting quantitative data on the association between racism and health for adults and/or children of all ages from any racial/ethnic/cultural groups. Outcome measures will include general health and well-being, physical health, mental health, healthcare use and health behaviors. Scientific databases (for example, Medline) will be searched using a comprehensive search strategy and reference lists will be manually searched for relevant studies. In addition, use of online search engines (for example, Google Scholar), key websites, and personal contact with experts will also be undertaken. Screening of search results and extraction of data from included studies will be independently conducted by at least two authors, including assessment of inter-rater reliability. Studies included in the review will be appraised for quality using tools tailored to each study design. Summary statistics of study characteristics and findings will be compiled and findings synthesized in a narrative summary as well as a meta-analysis. This review aims to examine associations between reported racism and health outcomes. This comprehensive and systematic review and meta-analysis of empirical research will provide a rigorous and

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

Science.gov (United States)

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

2018-03-01

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

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

Science.gov (United States)

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

2017-01-01

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

The Relationship between physical activity and risk of atrial fibrillation-A systematic review and meta-Analysis

DEFF Research Database (Denmark)

Nielsen, Jens Erik Rokkedal; Wachtell, K; Abdulla, J

2013-01-01

The aim of this systematic literature review and meta-Analyses was to explore the relationship between physical activity and risk of new-onset atrial fibrillation (AF) or flutter (AFlu).Results: The search revealed 10 published studies that were eligible for three different meta-Analyses. A meta...

Stuttering as a trait or state - an ALE meta-analysis of neuroimaging studies.

Science.gov (United States)

Belyk, Michel; Kraft, Shelly Jo; Brown, Steven

2015-01-01

Stuttering is a speech disorder characterised by repetitions, prolongations and blocks that disrupt the forward movement of speech. An earlier meta-analysis of brain imaging studies of stuttering (Brown et al., 2005) revealed a general trend towards rightward lateralization of brain activations and hyperactivity in the larynx motor cortex bilaterally. The present study sought not only to update that meta-analysis with recent work but to introduce an important distinction not present in the first study, namely the difference between 'trait' and 'state' stuttering. The analysis of trait stuttering compares people who stutter (PWS) with people who do not stutter when behaviour is controlled for, i.e., when speech is fluent in both groups. In contrast, the analysis of state stuttering examines PWS during episodes of stuttered speech compared with episodes of fluent speech. Seventeen studies were analysed using activation likelihood estimation. Trait stuttering was characterised by the well-known rightward shift in lateralization for language and speech areas. State stuttering revealed a more diverse pattern. Abnormal activation of larynx and lip motor cortex was common to the two analyses. State stuttering was associated with overactivation in the right hemisphere larynx and lip motor cortex. Trait stuttering was associated with overactivation of lip motor cortex in the right hemisphere but underactivation of larynx motor cortex in the left hemisphere. These results support a large literature highlighting laryngeal and lip involvement in the symptomatology of stuttering, and disambiguate two possible sources of activation in neuroimaging studies of persistent developmental stuttering. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

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

Science.gov (United States)

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

2017-07-01

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

A meta-frontier approach for causal inference in productivity analysis

DEFF Research Database (Denmark)

Henningsen, Arne; Mpeta, Daniel F.; Adem, Anwar S.

(2012) and create a meta-frontier in order to estimate the effects of participation on the farms’ meta-technology ratio, their group technical efficiency, and their meta-technology technical efficiency. The empirical analysis uses a cross-sectional data set from sunflower farmers in Tanzania, where some...... by the contractor’s provision of (additional) extension service and seeds of high-yielding varieties to the contract farmers....

A Bayesian Network Meta-Analysis to Synthesize the Influence of Contexts of Scaffolding Use on Cognitive Outcomes in STEM Education

Science.gov (United States)

Belland, Brian R.; Walker, Andrew E.; Kim, Nam Ju

2017-01-01

Computer-based scaffolding provides temporary support that enables students to participate in and become more proficient at complex skills like problem solving, argumentation, and evaluation. While meta-analyses have addressed between-subject differences on cognitive outcomes resulting from scaffolding, none has addressed within-subject gains. This leaves much quantitative scaffolding literature not covered by existing meta-analyses. To address this gap, this study used Bayesian network meta-analysis to synthesize within-subjects (pre–post) differences resulting from scaffolding in 56 studies. We generated the posterior distribution using 20,000 Markov Chain Monte Carlo samples. Scaffolding has a consistently strong effect across student populations, STEM (science, technology, engineering, and mathematics) disciplines, and assessment levels, and a strong effect when used with most problem-centered instructional models (exception: inquiry-based learning and modeling visualization) and educational levels (exception: secondary education). Results also indicate some promising areas for future scaffolding research, including scaffolding among students with learning disabilities, for whom the effect size was particularly large (ḡ = 3.13). PMID:29200508

Systematic review and meta-analysis of educational interventions designed to improve medication administration skills and safety of registered nurses.

Science.gov (United States)

Härkänen, Marja; Voutilainen, Ari; Turunen, Elina; Vehviläinen-Julkunen, Katri

2016-06-01

The aim of this study is to evaluate the nature, quality and effectiveness of educational interventions designed to increase the medication administration skills and safety of registered nurses working in hospitals. A systematic review with meta-analysis. Intervention studies designed to increase the medication administration skills and safety of nurses, indexed in one or more databases (CINAHL, PubMed, Scopus, Cochrane, PsycInfo, or Medic), and published in peer-reviewed journals between January 2000 and April 2015. The nature of the interventions was evaluated by narrative analysis, the quality of studies was assessed using the Effective Public Health Practise Project Quality Assessment Tool and the effectiveness of the interventions was ascertained by calculating effect sizes and conducting a meta-analysis. A total of 755 studies were identified and 14 intervention studies were reviewed. Interventions differed by their nature, including traditional classroom training, simulation, e-learning, slide show presentations, interactive CD-ROM programme, and the use of posters and pamphlets. All interventions appeared to improve medication administration safety and skills based on original p-values. Only five studies reached strong (n=1) or moderate (n=4) quality ratings and one of them had to be omitted from the meta-analysis due unclear measures of dispersion. The meta-analysis favoured the interventions, the pooled effect size (Hedges' g) was large, 1.06. The most effective interventions were a blended learning programme including e-learning and a 60-min PowerPoint presentation. The least effective educational intervention, an interactive internet-based e-learning course, was reported in the study that achieved the only strong quality rating. It is challenging to recommend any specific intervention, because all educational interventions seem to have a positive effect, although the size of the effect greatly varies. In the future, studies sharing similar contents and

Religion and Completed Suicide: a Meta-Analysis.

Science.gov (United States)

Wu, Andrew; Wang, Jing-Yu; Jia, Cun-Xian

2015-01-01

Suicide is a major public health concern and a leading cause of death around the world. How religion influences the risk of completed suicide in different settings across the world requires clarification in order to best inform suicide prevention strategies. A meta-analysis using search results from Pubmed and Web of Science databases was conducted following PRISMA protocol and using the keywords "religion" or "religious" or "religiosity" or "spiritual" or "spirituality" plus "suicide" or "suicidality" or "suicide attempt". Random and fixed effects models were used to generate pooled ORs and I2 values. Sub-analyses were conducted among the following categories: young age (Religion plays a protective role against suicide in a majority of settings where suicide research is conducted. However, this effect varies based on the cultural and religious context. Therefore, public health professionals need to strongly consider the current social and religious atmosphere of a given population when designing suicide prevention strategies.

Radiosurgery of Glomus Jugulare Tumors: A Meta-Analysis

International Nuclear Information System (INIS)

Guss, Zachary D.; Batra, Sachin; Limb, Charles J.; Li, Gordon; Sughrue, Michael E.; Redmond, Kristin; Rigamonti, Daniele; Parsa, Andrew T.; Chang, Steven; Kleinberg, Lawrence; Lim, Michael

2011-01-01

Purpose: During the past two decades, radiosurgery has arisen as a promising approach to the management of glomus jugulare. In the present study, we report on a systematic review and meta-analysis of the available published data on the radiosurgical management of glomus jugulare tumors. Methods and Materials: To identify eligible studies, systematic searches of all glomus jugulare tumors treated with radiosurgery were conducted in major scientific publication databases. The data search yielded 19 studies, which were included in the meta-analysis. The data from 335 glomus jugulare patients were extracted. The fixed effects pooled proportions were calculated from the data when Cochrane's statistic was statistically insignificant and the inconsistency among studies was 36 months. In these studies, 95% of patients achieved clinical control and 96% achieved tumor control. The gamma knife, linear accelerator, and CyberKnife technologies all exhibited high rates of tumor and clinical control. Conclusions: The present study reports the results of a meta-analysis for the radiosurgical management of glomus jugulare. Because of its high effectiveness, we suggest considering radiosurgery for the primary management of glomus jugulare tumors.

Meta-analysis of genome wide association studies for the stature of cattle reveals numerous common genes that regulate size in mammals

Science.gov (United States)

Stature is affected by many polymorphisms of small effect in humans but in contrast variation in dogs, even within breeds is largely due to variants in six genes. Here we use data from cattle to compare genetic architecture of stature to that in humans and dogs. We conducted a meta-analysis for stat...

A meta-analysis of serious digital games for healthy lifestyle promotion

Science.gov (United States)

Several systematic reviews have described health-promoting effects of serious games, but so far no meta-analysis has been reported. This paper presents a meta-analysis of 54 serious digital game studies for healthy lifestyle promotion, in which we investigated the overall effectiveness of serious di...

Interleukin-8 for diagnosis of neonatal sepsis: a meta-analysis.

Directory of Open Access Journals (Sweden)

Min Zhou

Full Text Available Neonatal sepsis (NS is a life-threatening disorder and an important cause of morbidity and mortality in neonates. Previous studies showed that interleukin 8 (IL-8 may effectively and rapidly diagnose NS.We conducted the systematic review and meta-analysis to investigate the diagnostic value of the IL-8 in NS.The literature was searched in PUBMED, EMBASE, Cochrane Library, CNKI, VIP and other Chinese Medical Databases during October 1998 to January 2014 using set search criteria. Each included study was evaluated by quality assessment of diagnostic accuracy studies tool. Two investigators independently extracted the data and study characteristics, and disagreements, if any, were resolved by consensus. Meta-disc software was used to calculate the pooled sensitivity, specificity and summary diagnostic odds ratio (SDOR, I² or Cochrane Q to test heterogeneity, and meta-regression to investigate the source of heterogeneity. Funnel plots were used to test the potential presence of publication bias. False-positive report probability (FPRP was calculated to confirm the significance of the results.Eight studies (548 neonates were included in this meta-analysis. The pooled sensitivity and specificity of IL-8 were 0.78 and 0.84, respectively, which had moderate accuracy in the diagnosis of NS. The pooled diagnostic odds ratio (DOR and area under curve (AUC was 21.64 and 0.8908 (Q*=0.8215, respectively. The diagnostic threshold analysis showed that there was no threshold effect. The meta-regression analysis showed the cut-off, QUADAS and onset time have no effect on the heterogeneity. The funnel plots showed the existence of publication bias.Meta-analysis showed IL-8 had a moderate accuracy (AUC=0.8908 for the diagnosis of NS. IL-8 is a helpful biomarker for early diagnosis of NS. However, we should combine the results with clinical symptoms and signs, laboratory and microbial results.

Wood dust exposure and lung cancer risk: a meta-analysis.

Science.gov (United States)

Hancock, David G; Langley, Mary E; Chia, Kwan Leung; Woodman, Richard J; Shanahan, E Michael

2015-12-01

Occupational lung cancers represent a major health burden due to their increasing prevalence and poor long-term outcomes. While wood dust is a confirmed human carcinogen, its association with lung cancer remains unclear due to inconsistent findings in the literature. We aimed to clarify this association using meta-analysis. We performed a search of 10 databases to identify studies published until June 2014. We assessed the lung cancer risk associated with wood dust exposure as the primary outcome and with wood dust-related occupations as a secondary outcome. Random-effects models were used to pool summary risk estimates. 85 publications were included in the meta-analysis. A significantly increased risk for developing lung cancer was observed among studies that directly assessed wood dust exposure (RR 1.21, 95% CI 1.05 to 1.39, n=33) and that assessed wood dust-related occupations (RR 1.15, 95% CI 1.07 to 1.23, n=59). In contrast, a reduced risk for lung cancer was observed among wood dust (RR 0.63, 95% CI 0.39 to 0.99, n=5) and occupation (RR 0.96, 95% CI 0.95 to 0.98, n=1) studies originating in Nordic countries, where softwood dust is the primary exposure. These results were independent of the presence of adjustment for smoking and exposure classification methods. Only minor differences in risk between the histological subtypes were identified. This meta-analysis provides strong evidence for an association between wood dust and lung cancer, which is critically influenced by the geographic region of the study. The reasons for this region-specific effect estimates remain to be clarified, but may suggest a differential effect for hardwood and softwood dusts. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Long-term Hearing Preservation After Resection of Vestibular Schwannoma: A Systematic Review and Meta-analysis.

Science.gov (United States)

Ahsan, Syed F; Huq, Farhan; Seidman, Michael; Taylor, Andrew

2017-12-01

The objective is to perform a systematic review and meta-analysis of the literature on the long-term results of hearing preservation after vestibular schwannoma resection. Ovid/Medline, PubMed, Embase, and the Cochrane library from January 1980 to January 2015. Inclusion criteria: age ≥18 years, minimum 10 patients in the treatment group, hearing preserving microsurgery, no previous radiation treatment, serviceable hearing at immediate postop follow-up, hearing outcomes reported using Gardner Robinson or the American Academy of Otolaryngology-Head and Neck Surgeons hearing grading scales, and average follow-up of 5 years. Preoperative, immediate postoperative, and last follow-up audiograms were required. Exclusion criteria included neurofibromatosis type 2 patients and surgery for salvage therapy or decompression. Quality evaluated using Methodological Index for Non-Randomized Studies. Meta-analysis was performed using R v3.2.2, Metafor package v 1.9-7. Cohen's D was used to determine effect size. Ten reports had at least 5-year follow-up and used standardized hearing grading scales. The systematic review found that if hearing was preserved at Class A or B at early postop visit, the chance of preserving hearing at 5 years was excellent. Those who maintained speech discrimination score ≥ 89% at the early postoperative follow-up had better long-term hearing preservation. The meta-analysis reveals that only preoperative and postoperative pure-tone average was associated with long-term hearing preservation. Long-term (>5 yr) hearing durability rates are generally very good. Most studies do not report patient and tumor characteristics, therefore precluding combining studies for meta-analysis. Only preoperative and postoperative postoperative pure-tone average was associated with long-term hearing durability.

Effect of Herbal Medicine on Vaginal Epithelial Cells: A Systematic Review and Meta-analysis.

Science.gov (United States)

Rahmani, Yousef; Chaleh, Khadijeh Chaleh; Shahmohammadi, Afshar; Safari, Shahla

2018-04-01

The present meta-analysis aimed to assess the effect of the herbal medicine on the vaginal epithelial cells (VECs) among the menopausal subjects. The literature related to VECs exposed to various herbal medicines in menopausal women were searched on three databases, MEDLINE (1966-August 2017), Scopus (1990-August 2017) and Cochrane Library (Cochrane Central Register of Controlled Trials; 2014). Totally, the meta-analysis was conducted on 11 randomised controlled trials. Based on the findings, the standardized mean difference (SMD) of maturation value (MV) was observed to be elevated by 0.48% (95% interval confidence [CI], 0.108-0.871; P = 0.012), as well as the heterogeneity was high (I 2 = 84%; P < 0.001). The MV revealed a significant increase in soy group (SMD, 0.358; 95% CI, 0.073-0.871; P = 0.014) compared to the control group. The herbal medicines exhibited a statistically significant effect on the VECs. A significant effect on the VECs was also found in the subgroup analysis of the patients, who received soy. However, further and extensive studies are required to achieve reliable outcomes.

Dose-Dependent Effects of Statins for Patients with Aneurysmal Subarachnoid Hemorrhage: Meta-Regression Analysis.

Science.gov (United States)

To, Minh-Son; Prakash, Shivesh; Poonnoose, Santosh I; Bihari, Shailesh

2018-05-01

The study uses meta-regression analysis to quantify the dose-dependent effects of statin pharmacotherapy on vasospasm, delayed ischemic neurologic deficits (DIND), and mortality in aneurysmal subarachnoid hemorrhage. Prospective, retrospective observational studies, and randomized controlled trials (RCTs) were retrieved by a systematic database search. Summary estimates were expressed as absolute risk (AR) for a given statin dose or control (placebo). Meta-regression using inverse variance weighting and robust variance estimation was performed to assess the effect of statin dose on transformed AR in a random effects model. Dose-dependence of predicted AR with 95% confidence interval (CI) was recovered by using Miller's Freeman-Tukey inverse. The database search and study selection criteria yielded 18 studies (2594 patients) for analysis. These included 12 RCTs, 4 retrospective observational studies, and 2 prospective observational studies. Twelve studies investigated simvastatin, whereas the remaining studies investigated atorvastatin, pravastatin, or pitavastatin, with simvastatin-equivalent doses ranging from 20 to 80 mg. Meta-regression revealed dose-dependent reductions in Freeman-Tukey-transformed AR of vasospasm (slope coefficient -0.00404, 95% CI -0.00720 to -0.00087; P = 0.0321), DIND (slope coefficient -0.00316, 95% CI -0.00586 to -0.00047; P = 0.0392), and mortality (slope coefficient -0.00345, 95% CI -0.00623 to -0.00067; P = 0.0352). The present meta-regression provides weak evidence for dose-dependent reductions in vasospasm, DIND and mortality associated with acute statin use after aneurysmal subarachnoid hemorrhage. However, the analysis was limited by substantial heterogeneity among individual studies. Greater dosing strategies are a potential consideration for future RCTs. Copyright © 2018 Elsevier Inc. All rights reserved.

The Neural Correlates of Moral Thinking: A Meta-Analysis

OpenAIRE

Douglas J. Bryant; Wang F; Kelley Deardeuff; Emily Zoccoli; Chang S. Nam

2016-01-01

We conducted a meta-analysis to evaluate current research that aims to map the neural correlates of two typical conditions of moral judgment: right-wrong moral judgments and decision-making in moral dilemmas. Utilizing the activation likelihood estimation (ALE) method, we conducted a meta-analysis using neuroimaging data obtained from twenty-one previous studies that measured responses in one or the other of these conditions. We found that across the studies (n = 400), distinct neural circuit...

Meta-analysis: Nitroglycerin for prevention of post-ERCP pancreatitis

DEFF Research Database (Denmark)

Nøjgaard, C; Matzen, P; Andersen, Per Kragh

2009-01-01

BACKGROUND: Acute pancreatitis after ERCP is a severe side effect. AIM: To evaluate the preventive effect of nitroglycerin on post-ERCP pancreatitis by a meta-analysis of randomized clinical studies. METHODS: We searched on Pubmed, Embase, Cochrane Library and all abstracts presented at Digestive......-ERCP pancreatitis after administration of nitroglycerin were identified. Meta-analysis including all five studies showed a relative risk (RR) of 0.61 (95% CI; 0.44, 0.86) with the number needed to treat (NNT) of 26 (95% CI: 16, 82). Three studies evaluated nitroglycerin administered by a dermal patch reaching...... together an RR of 0.66 (95% CI; 0.43, 1.01). The use of nitroglycerin is associated with a significantly increased risk of hypotension (RR 2.25) and headache (RR 3.64). No difference in mortality was observed. CONCLUSIONS: Overall, our meta-analysis supports the use of nitroglycerin in the prevention...

Meta-analysis identifies 13 new loci associated with waist-hip ratio and reveals sexual dimorphism in the genetic basis of fat distribution

NARCIS (Netherlands)

I.M. Heid (Iris); A.U. Jackson (Anne); J.C. Randall (Joshua); T.W. Winkler (Thomas); L. Qi (Lu); V. Ssteinthorsdottir (Valgerdur); G. Tthorleifsson (Ggudmar); M.C. Zillikens (Carola); E.K. Sspeliotes (Eelizabeth); R. Mägi (Reedik); T. Workalemahu (Tsegaselassie); C.C. White (Charles); N. Bouatia-Naji (Nabila); T.B. Harris (Tamara); S.I. Berndt (Sonja); E. Ingelsson (Erik); C.J. Willer (Cristen); J. Luan; S. Vedantam (Sailaja); T. Eesko (Tõnu); T.O. Kilpeläinen (Tuomas); Z. Kutalik (Zoltán); S. Li (Shengxu); K.L. Monda (Keri); A.L. Dixon (Anna); C. Holmes (Christopher); R.C. Kaplan (Robert); L. Liang (Liming); J. Min (Josine); M.F. Moffatt (Miriam); C. Molony (Cliona); G. Nicholson (Ggeorge); E.E. Sschadt (Eeric); K.T. Zondervan (Krina); M.F. Feitosa (Mary Furlan); T. Ferreira (Teresa); H.L. Allen; R.J. Weyant (Robert); E. Wheeler (Eleanor); A.R. Wood (Andrew); K. Eestrada (Karol); M.E. Goddard (Michael); G. Lettre (Guillaume); M. Mangino (Massimo); D.R. Nyholt (Dale); S. Purcell (Shaun); A.V. Ssmith; P.M. Visscher (Peter); J. Yang (Joanna); S.A. McCcarroll (Ssteven); J. Nemesh (James); B.F. Voight (Benjamin); D. Absher (Devin); N. Amin (Najaf); T. Aspelund (Thor); L. Coin (Lachlan); N.L. Glazer (Nicole); C. Hayward (Caroline); N. Heard-Ccosta (Nancy); J.J. Hottenga (Jouke Jan); A. Johansson (Åsa); T. Johnson (Toby); M. Kaakinen (Marika); K. Kapur (Karen); S. Ketkar (Shamika); J.W. Knowles (Joshua); P. Kraft (Peter); A. Kraja (Aldi); C. Lamina (Claudia); M.F. Leitzmann (Michael); B. McKknight (Barbara); A.D. Morris (Andrew); K. Oong (Ken); J.R.B. Perry (John); M.J. Peters (Marjolein); O. Polasek (Ozren); I. Prokopenko (Inga); N.W. Rayner (Nigel William); S. Ripatti (Samuli); F. Rivadeneira Ramirez (Fernando); N.R. Robertson (Neil); S. Sanna (Serena); U. Sovio (Ulla); I. Surakka (Ida); A. Teumer (Alexander); S. van Wingerden (Sophie); V. Vitart (Veronique); J.H. Zhao (Jing Hua); C. Cavalcanti-Proença (Christine); P.S. Chines (Peter); E. Fisher (Eeva); J.R. Kulzer (Jennifer); C. Lecoeur (Cécile); N. Narisu (Narisu); C. Sandholt (Camilla); L.J. Scott (Laura); K. Silander (Kaisa); K. Stark (Klaus); M.L. Tammesoo; T.M. Teslovich (Tanya); N.J. Timpson (Nicholas); R.P. Welch (Ryan); D.I. Chasman (Daniel); M.N. Cooper (Matthew); J.O. Jansson; J. Kettunen (Johannes); R. Wlawrence (Robert); N. Pellikka (Niina); M. Perola (Markus); L. Vandenput (Liesbeth); H. Alavere (Helene); P. Almgren (Peter); L.D. Atwood (Larry); A.J. Bennett (Amanda); R. Biffar (Reiner); L.L. Bonnycastle (Lori); S.R. Bornstein (Stefan); T.A. Buchanan (Thomas); H. Campbell (Harry); I.N.M. Day (Ian); M. Dei (Mariano); M. Dörr (Marcus); P. Eelliott (Paul); M.R. Eerdos (Micheal); J.G. Eeriksson (Johan); N.B. Freimer (Nelson); M. Fu (Mao); S. Gaget (Stefan); E.J.C. de Geus (Eco); A.P. Gjesing (Anette); H. Grallert (Harald); J. Gräßler (Jürgen); C.J. Groves (Christopher); C. Guiducci (Candace); A.L. Hartikainen; N. Hassanali (Neelam); A.S. Havulinna (Aki); K.H. Herzig; A.A. Hicks (Andrew); J. Hui (Jennie); W. Igl (Wilmar); P. Jousilahti (Pekka); A. Jula (Antti); E. Kajantie (Eero); L. Kinnunen (Leena); I. Kolcic (Ivana); S. Koskinen (Seppo); P. Kovacs (Peter); H.K. Kroemer (Heyo); V. Krzelj (Vjekoslav); J. Kuusisto (Johanna); K. Kvaløy (Kirsti); J. Laitinen (Jaana); O. Lantieri (Olivier); G.M. Lathrop (Mark); M.L. Lokki; R.N. Luben (Robert); B. Ludwig (Barbara); W.L. McArdle (Wendy); A. McCcarthy (Anne); M.A. Morken (Mario); M. Nelis (Mari); M.J. Neville (Matthew); G. Paré (Guillaume); A.N. Parker (Alex); J. Peden (John); I. Pichler (Irene); K.H. Pietilainen (Kirsi Hannele); C.P. Platou (Carl); A. Pouta (Anneli); M. Ridderstråle (Martin); N.J. Samani (Nilesh); J. Saramies (Jouko); J. Sinisalo (Juha); J.H. Smit (Jan); R.J. Strawbridge (Rona); H.M. Stringham (Heather); A.J. Swift (Amy); M. Teder-Llaving (Maris); B. Thomson (Brian); G. Usala; J.B.J. van Meurs (Joyce); G.J. van Ommen (Gert); V. Vatin (Vincent); C.B. Volpato; H. Wallaschofski (Henri); G.B. Walters (Bragi); E. Widen (Elisabeth); S.H. Wild (Sarah); G.A.H.M. Willemsen (Gonneke); D.R. Witte (Deniel); L. Zgaga (Lina); P. Zitting (Paavo); J.P. Beilby (John); A. James (Alan); M. Kähönen (Mika); T. Lehtimäki (Terho); M.S. Nieminen (Markku); C. Ohlsson (Claes); C. Palmer (Cameron); O. Raitakari (Olli); P.M. Ridker (Paul); M. Stumvoll (Michael); A. Tönjes (Anke); J. Viikari (Jorma); B. Balkau (Beverley); Y. Ben-Shlomo; R.N. Bergman (Richard); H. Boeing (Heiner); A.V. Smith (Albert Vernon); S. Eebrahim (Shah); P. Froguel (Philippe); T. Hansen (Torben); C. Hengstenberg (Christian); K. Hveem (Kristian); B. Isomaa (Bo); T. Jørgensen (Torben); F. Karpe (Fredrik); K-T. Khaw (Kay-Tee); M. Laakso (Markku); D.A. Lawlor (Debbie); M. Marre (Michel); T. Meitinger (Thomas); A. Metspalu (Andres); K. Midthjell (Kristian); O. Pedersen (Oluf); V. Salomaa (Veikko); P.E.H. Schwarz (Peter); T. Tuomi (Tiinamaija); J. Tuomilehto (Jaakko); T.T. Valle (Timo); N.J. Wareham (Nick); A.M. Arnold (Alice); J.S. Beckmann (Jacques); S.M. Bergmann (Sven); E.A. Boerwinkle (Eric); D.I. Boomsma (Dorret); M. Caulfield (Mark); F.S. Collins (Francis); G. Eeiriksdottir (Gudny); V. Gudnason (Vilmundur); U. Gyllensten (Ulf); A. Hamsten (Anders); A.T. Hattersley (Andrew); A. Hofman (Albert); F.B. Hu (Frank); T. Illig (Thomas); C. Iribarren (Carlos); M.R. Järvelin; W.H.L. Kao (Wen); J. Kaprio (Jaakko); L.J. Launer (Lenore); P. Munroe (Patricia); B.A. Oostra (Ben); B.W.J.H. Penninx (Brenda); P.P. Pramstaller (Peter Paul); B.M. Psaty (Bruce); T. Quertermous (Thomas); A. Rissanen (Aila); I. Rudan (Igor); A.R. Shuldiner (Alan); N. Soranzo (Nicole); T.D. Spector (Timothy); A.C. Syvanen; M. Uda (Manuela); A.G. Uitterlinden (André); H. Völzke (Henry); P. Vollenweider (Peter); J.F. Wilson (James); J.C.M. Witteman (Jacqueline); A.F. Wright (Alan); G.R. Abecasis (Gonçalo); M. Boehnke (Michael); I.B. Borecki (Ingrid); P. Deloukas (Panagiotis); T.M. Frayling (Timothy); L. Groop (Leif); T. Haritunians (Talin); D.J. Hunter (David); K.E. North (Kari); J.R. O'Cconnell (Jeffrey); L. Peltonen (Leena Johanna); D. Schlessinger; D.P. Strachan (David); J.N. Hirschhorn (Joel); T.L. Assimes (Themistocles); H.E. Wichmann (Heinz Erich); U. Thorsteinsdottir (Unnur); C.M. van Duijn (Cornelia); K. Stefansson (Kari); L.A. Cupples (Adrienne); R.J.F. Loos (Ruth); I.E. Barroso (Inês); C.S. Fox (Caroline); K.L. Mohlke (Karen); C.M. Lindgren (Cecilia); R.M. Watanabe (Richard); M.N. Weedon (Michael)

2010-01-01

textabstractWaist-hip ratio (WHR) is a measure of body fat distribution and a predictor of metabolic consequences independent of overall adiposity. WHR is heritable, but few genetic variants influencing this trait have been identified. We conducted a meta-analysis of 32 genome-wide association

Abnormal brain activation during threatening face processing in schizophrenia: A meta-analysis of functional neuroimaging studies.

Science.gov (United States)

Dong, Debo; Wang, Yulin; Jia, Xiaoyan; Li, Yingjia; Chang, Xuebin; Vandekerckhove, Marie; Luo, Cheng; Yao, Dezhong

2017-11-15

Impairment of face perception in schizophrenia is a core aspect of social cognitive dysfunction. This impairment is particularly marked in threatening face processing. Identifying reliable neural correlates of the impairment of threatening face processing is crucial for targeting more effective treatments. However, neuroimaging studies have not yet obtained robust conclusions. Through comprehensive literature search, twenty-one whole brain datasets were included in this meta-analysis. Using seed-based d-Mapping, in this voxel-based meta-analysis, we aimed to: 1) establish the most consistent brain dysfunctions related to threating face processing in schizophrenia; 2) address task-type heterogeneity in this impairment; 3) explore the effect of potential demographic or clinical moderator variables on this impairment. Main meta-analysis indicated that patients with chronic schizophrenia demonstrated attenuated activations in limbic emotional system along with compensatory over-activation in medial prefrontal cortex (MPFC) during threatening faces processing. Sub-task analyses revealed under-activations in right amygdala and left fusiform gyrus in both implicit and explicit tasks. The remaining clusters were found to be differently involved in different types of tasks. Moreover, meta-regression analyses showed brain abnormalities in schizophrenia were partly modulated by age, gender, medication and severity of symptoms. Our results highlighted breakdowns in limbic-MPFC circuit in schizophrenia, suggesting general inability to coordinate and contextualize salient threat stimuli. These findings provide potential targets for neurotherapeutic and pharmacological interventions for schizophrenia. Copyright © 2017 Elsevier B.V. All rights reserved.

Educational intervention on physical restraint use in long-term care facilities - Systematic review and meta-analysis.

Science.gov (United States)

Lan, Shao-Huan; Lu, Li-Chin; Lan, Shou-Jen; Chen, Jong-Chen; Wu, Wen-Jun; Chang, Shen-Peng; Lin, Long-Yau

2017-08-01

"Physical restraint" formerly used as a measure of protection for psychiatric patients is now widely used. However, existing studies showed that physical restraint not only has inadequate effect of protection but also has negative effects on residents. To analyzes the impact of educational program on the physical restraint use in long-term care facilities. A systematic review with meta-analysis and meta-regression. Eight databases, including Cochrane Library, ProQuest, PubMed, EMBASE, EBSCO, Web of Science, Ovid Medline and Physiotherapy Evidence Database (PEDro), were searched up to January 2017. Eligible studies were classified by intervention and accessed for quality using the Quality Assessment Tool for quantitative studies. Sixteen research articles were eligible in the final review; 10 randomize control trail studies were included in the analysis. The meta-analysis revealed that the use of physical restraint was significantly less often in the experimental (education) group (OR = 0.55, 95% CI: 0.39 to 0.78, p education would have decreased the effect of the restraint educational program (β: 0.08, p = 0.002); instead, the longer education period and more times of education would have a stronger effect of reducing the use of physical restraint (β: -0.07, p educational program had an effect on the reduced use of physical restraint. The results of meta-regression suggest that long-term care facilities should provide a continuous education program of physical restraint for caregivers. Copyright © 2017. Published by Elsevier Taiwan.

A systematic review and meta-analysis of sleep architecture and chronic traumatic brain injury.

Science.gov (United States)

Mantua, Janna; Grillakis, Antigone; Mahfouz, Sanaa H; Taylor, Maura R; Brager, Allison J; Yarnell, Angela M; Balkin, Thomas J; Capaldi, Vincent F; Simonelli, Guido

2018-02-02

Sleep quality appears to be altered by traumatic brain injury (TBI). However, whether persistent post-injury changes in sleep architecture are present is unknown and relatively unexplored. We conducted a systematic review and meta-analysis to assess the extent to which chronic TBI (>6 months since injury) is characterized by changes to sleep architecture. We also explored the relationship between sleep architecture and TBI severity. In the fourteen included studies, sleep was assessed with at least one night of polysomnography in both chronic TBI participants and controls. Statistical analyses, performed using Comprehensive Meta-Analysis software, revealed that chronic TBI is characterized by relatively increased slow wave sleep (SWS). A meta-regression showed moderate-severe TBI is associated with elevated SWS, reduced stage 2, and reduced sleep efficiency. In contrast, mild TBI was not associated with any significant alteration of sleep architecture. The present findings are consistent with the hypothesis that increased SWS after moderate-severe TBI reflects post-injury cortical reorganization and restructuring. Suggestions for future research are discussed, including adoption of common data elements in future studies to facilitate cross-study comparability, reliability, and replicability, thereby increasing the likelihood that meaningful sleep (and other) biomarkers of TBI will be identified. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bayesian meta-analysis models for microarray data: a comparative study

Directory of Open Access Journals (Sweden)

Song Joon J

2007-03-01

Full Text Available Abstract Background With the growing abundance of microarray data, statistical methods are increasingly needed to integrate results across studies. Two common approaches for meta-analysis of microarrays include either combining gene expression measures across studies or combining summaries such as p-values, probabilities or ranks. Here, we compare two Bayesian meta-analysis models that are analogous to these methods. Results Two Bayesian meta-analysis models for microarray data have recently been introduced. The first model combines standardized gene expression measures across studies into an overall mean, accounting for inter-study variability, while the second combines probabilities of differential expression without combining expression values. Both models produce the gene-specific posterior probability of differential expression, which is the basis for inference. Since the standardized expression integration model includes inter-study variability, it may improve accuracy of results versus the probability integration model. However, due to the small number of studies typical in microarray meta-analyses, the variability between studies is challenging to estimate. The probability integration model eliminates the need to model variability between studies, and thus its implementation is more straightforward. We found in simulations of two and five studies that combining probabilities outperformed combining standardized gene expression measures for three comparison values: the percent of true discovered genes in meta-analysis versus individual studies; the percent of true genes omitted in meta-analysis versus separate studies, and the number of true discovered genes for fixed levels of Bayesian false discovery. We identified similar results when pooling two independent studies of Bacillus subtilis. We assumed that each study was produced from the same microarray platform with only two conditions: a treatment and control, and that the data sets

Quality of life in autism across the lifespan: A meta-analysis

NARCIS (Netherlands)

van Heijst, B.F.C.; Geurts, H.M.

2015-01-01

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

A Systematic Review and Meta-analysis of Childhood Health Utilities.

Science.gov (United States)

Kwon, Joseph; Kim, Sung Wook; Ungar, Wendy J; Tsiplova, Kate; Madan, Jason; Petrou, Stavros

2018-04-01

-effects meta-regressions estimated that 53 of 76 ICD-10 delineated health conditions, valued using the HUI3, were associated with statistically significant utility decrements relative to general population health, whereas 38 of 57 valued using a visual analog scale (VAS) were associated with statistically significant VAS decrements. For both methods, parental proxy assessment was associated with overestimation of values, whereas adolescents reported lower values than children under 12 y. VAS responses were more heavily influenced by mode of administration than the HUI3. Utilities and their associated distributions, as well as the independent contributions of methodological factors, revealed by this systematic review and meta-analysis can inform future economic evaluations within the childhood context.

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

Science.gov (United States)

Kukimoto, Yukiko; Ooe, Noriko; Ideguchi, Norio

2017-12-01

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

Physical activity and physical self-concept in youth: systematic review and meta-analysis.

Science.gov (United States)

Babic, Mark J; Morgan, Philip J; Plotnikoff, Ronald C; Lonsdale, Chris; White, Rhiannon L; Lubans, David R

2014-11-01

Evidence suggests that physical self-concept is associated with physical activity in children and adolescents, but no systematic review of this literature has been conducted. The primary aim of this systematic review and meta-analysis was to determine the strength of associations between physical activity and physical self-concept (general and sub-domains) in children and adolescents. The secondary aim was to examine potential moderators of the association between physical activity and physical self-concept. A systematic search of six electronic databases (MEDLINE, CINAHL, SPORTDiscus, ERIC, Web of Science and Scopus) with no date restrictions was conducted. Random effects meta-analyses with correction for measurement were employed. The associations between physical activity and general physical self-concept and sub-domains were explored. A risk of bias assessment was conducted by two reviewers. The search identified 64 studies to be included in the meta-analysis. Thirty-three studies addressed multiple outcomes of general physical self-concept: 28 studies examined general physical self-concept, 59 examined perceived competence, 25 examined perceived fitness, and 55 examined perceived appearance. Perceived competence was most strongly associated with physical activity (r = 0.30, 95% CI 0.24-0.35, p self-concept (r = 0.25, 95% CI 0.16-0.34, p self-concept (p self-concept and its various sub-domains in children and adolescents. Age and sex are key moderators of the association between physical activity and physical self-concept.

Contemporary management of frontal sinus mucoceles: a meta-analysis.

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Courson, Andy M; Stankiewicz, James A; Lal, Devyani

2014-02-01

To analyze trends in the surgical management of frontal and fronto-ethmoid mucoceles through meta-analysis. Meta-analysis and case series. A systematic literature review on surgical management of frontal and fronto-ethmoid mucoceles was conducted. Studies were divided into historical (1975-2001) and contemporary (2002-2012) groups. A meta-analysis of these studies was performed. The historical and contemporary cohorts were compared (surgical approach, recurrence, and complications). To study evolution in surgical management, a senior surgeon's experience over 28 years was analyzed separately. Thirty-one studies were included for meta-analysis. The historical cohort included 425 mucoceles from 11 studies. The contemporary cohort included 542 mucoceles from 20 studies. More endoscopic techniques were used in the contemporary versus historical cohort (53.9% vs. 24.7%; P = contemporary). In the historical cohort, higher recurrence was noted in the external group (P = 0.03). Results from endoscopic and open approaches are comparable. Although endoscopic techniques are being increasingly adopted, comparison with our series shows that more cases could potentially be treated endoscopically. Frequent use of open approaches may reflect efficacy, or perhaps lack of expertise and equipment required for endoscopic management. Most contemporary authors favor endoscopic management, limiting open approaches for specific indications (unfavorable anatomy, lateral disease, and scarring). N/A. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

MetaFIND: A feature analysis tool for metabolomics data

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Cunningham Pádraig

2008-11-01

Full Text Available Abstract Background Metabolomics, or metabonomics, refers to the quantitative analysis of all metabolites present within a biological sample and is generally carried out using NMR spectroscopy or Mass Spectrometry. Such analysis produces a set of peaks, or features, indicative of the metabolic composition of the sample and may be used as a basis for sample classification. Feature selection may be employed to improve classification accuracy or aid model explanation by establishing a subset of class discriminating features. Factors such as experimental noise, choice of technique and threshold selection may adversely affect the set of selected features retrieved. Furthermore, the high dimensionality and multi-collinearity inherent within metabolomics data may exacerbate discrepancies between the set of features retrieved and those required to provide a complete explanation of metabolite signatures. Given these issues, the latter in particular, we present the MetaFIND application for 'post-feature selection' correlation analysis of metabolomics data. Results In our evaluation we show how MetaFIND may be used to elucidate metabolite signatures from the set of features selected by diverse techniques over two metabolomics datasets. Importantly, we also show how MetaFIND may augment standard feature selection and aid the discovery of additional significant features, including those which represent novel class discriminating metabolites. MetaFIND also supports the discovery of higher level metabolite correlations. Conclusion Standard feature selection techniques may fail to capture the full set of relevant features in the case of high dimensional, multi-collinear metabolomics data. We show that the MetaFIND 'post-feature selection' analysis tool may aid metabolite signature elucidation, feature discovery and inference of metabolic correlations.

Meta-analysis for quantitative microbiological risk assessments and benchmarking data

NARCIS (Netherlands)

Besten, den H.M.W.; Zwietering, M.H.

2012-01-01

Meta-analysis studies are increasingly being conducted in the food microbiology area to quantitatively integrate the findings of many individual studies on specific questions or kinetic parameters of interest. Meta-analyses provide global estimates of parameters and quantify their variabilities, and

Basal cortisol levels and metabolic syndrome: A systematic review and meta-analysis of observational studies.

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Garcez, Anderson; Leite, Heloísa Marquardt; Weiderpass, Elisabete; Paniz, Vera Maria Vieira; Watte, Guilherme; Canuto, Raquel; Olinto, Maria Teresa Anselmo

2018-05-17

and meta-analysis does not reveal any association between basal cortisol levels and MetS based on results of observational studies. The results of a random-effect meta-analysis showed no significant difference in basal cortisol levels between subjects with and without MetS. The present findings should be considered in order to help future studies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Prognostic value of LGR5 in colorectal cancer: a meta-analysis.

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Chen, Qing; Zhang, Xin; Li, Wei-Min; Ji, Yu-Qiang; Cao, Hao-Zhe; Zheng, Pengsheng

2014-01-01

Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) has recently been reported to be a marker of cancer stem cells (CSCs) in colorectal cancer (CRC), and the prognostic value of LGR5 in CRC has been evaluated in several studies. However, the conclusions remain controversial. In this study, we aimed to evaluate the association between the expression of LGR5 and the outcome of CRC patients by performing a meta-analysis. We systematically searched for relevant studies published up to February 2014 using the PubMed, Web of Science, EMBASE and Wangfang databases. Only articles in which LGR5 expression was detected by immunohistochemistry were included. A meta-analysis was performed using STATA 12.0, and pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were used to estimate the strength of the association between LGR5 expression and the prognosis of CRC patients. A total of 7 studies comprising 1833 CRC patients met the inclusion criteria, including 6 studies comprising 1781 patients for overall survival (OS) and 3 studies comprising 528 patients for disease-free survival (DFS). Our results showed that high LGR5 expression was significantly associated with poor prognosis in terms of OS (HR: 1.87, 95% CI: 1.23-2.84; P = 0.003) and DFS (HR: 2.44, 95% CI: 1.49-3.98; Panalysis revealed that many factors, including the study region, number of patients, follow-up duration and cutoff value, affected the significance of the association between LGR5 expression and a worse prognosis in patients with CRC. In addition, there was no evidence of publication bias, as suggested by Begg's and Egger's tests. The present meta-analysis indicated that high LGR5 expression was associated with poor prognosis in patients with CRC and that LGR5 is an efficient prognostic factor in CRC.

Association among Dietary Flavonoids, Flavonoid Subclasses and Ovarian Cancer Risk: A Meta-Analysis

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You, Ruxu; Yang, Yu; Liao, Jing; Chen, Dongsheng; Yu, Lixiu

2016-01-01

Background Previous studies have indicated that intake of dietary flavonoids or flavonoid subclasses is associated with the ovarian cancer risk, but presented controversial results. Therefore, we conducted a meta-analysis to derive a more precise estimation of these associations. Methods We performed a search in PubMed, Google Scholar and ISI Web of Science from their inception to April 25, 2015 to select studies on the association among dietary flavonoids, flavonoid subclasses and ovarian cancer risk. The information was extracted by two independent authors. We assessed the heterogeneity, sensitivity, publication bias and quality of the articles. A random-effects model was used to calculate the pooled risk estimates. Results Five cohort studies and seven case-control studies were included in the final meta-analysis. We observed that intake of dietary flavonoids can decrease ovarian cancer risk, which was demonstrated by pooled RR (RR = 0.82, 95% CI = 0.68–0.98). In a subgroup analysis by flavonoid subtypes, the ovarian cancer risk was also decreased for isoflavones (RR = 0.67, 95% CI = 0.50–0.92) and flavonols (RR = 0.68, 95% CI = 0.58–0.80). While there was no compelling evidence that consumption of flavones (RR = 0.86, 95% CI = 0.71–1.03) could decrease ovarian cancer risk, which revealed part sources of heterogeneity. The sensitivity analysis indicated stable results, and no publication bias was observed based on the results of Funnel plot analysis and Egger’s test (p = 0.26). Conclusions This meta-analysis suggested that consumption of dietary flavonoids and subtypes (isoflavones, flavonols) has a protective effect against ovarian cancer with a reduced risk of ovarian cancer except for flavones consumption. Nevertheless, further investigations on a larger population covering more flavonoid subclasses are warranted. PMID:26960146

Prognostic value of PLR in various cancers: a meta-analysis.

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Xin Zhou

Full Text Available BACKGROUND: Recently, more and more studies investigated the association of inflammation parameters such as the Platelet Lymphocyte Ratio (PLR and the prognosis of various cancers. However, the prognostic role of PLR in cancer remains controversial. METHODS: We conducted a meta-analysis of published studies to evaluate the prognostic value of PLR in various cancers. In order to investigate the association between PLR and overall survival (OS, the hazard ratio (HR and its 95% confidence interval (CI were calculated. RESULTS: A total of 13,964 patients from 26 studies were included in the analysis. The summary results showed that elevated PLR was a negative predictor for OS with HR of 1.60 (95%CI: 1.35-1.90; Pheterogeneity <0.001. Subgroup analysis revealed that increased PLR was a negative prognostic marker in patients with gastric cancer (HR = 1.35, 95%CI: 0.80-2.25, Pheterogeneity = 0.011, colorectal cancer (HR = 1.65, 95%CI: 1.33-2.05, Pheterogeneity = 0.995, hepatocellular carcinoma (HR = 3.07, 95% CI: 2.04-4.62, Pheterogeneity = 0.133, ovarian cancer (HR = 1.57, 95%CI: 1.07-2.31, Pheterogeneity = 0.641 and non-small cell lung cancer (NSCLC (HR = 1.85, 95% CI: 1.42-2.41, Pheterogeneity = 0.451 except for pancreatic cancer (HR = 1.00, 95%CI: 0.92-1.09, Pheterogeneity = 0.388. CONCLUSION: The meta-analysis demonstrated that PLR could act as a significant biomarker in the prognosis of various cancers.

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

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

2014-12-01

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

Identification of cytokinin-responsive genes using microarray meta-analysis and RNA-Seq in Arabidopsis.

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Bhargava, Apurva; Clabaugh, Ivory; To, Jenn P; Maxwell, Bridey B; Chiang, Yi-Hsuan; Schaller, G Eric; Loraine, Ann; Kieber, Joseph J

2013-05-01

Cytokinins are N(6)-substituted adenine derivatives that play diverse roles in plant growth and development. We sought to define a robust set of genes regulated by cytokinin as well as to query the response of genes not represented on microarrays. To this end, we performed a meta-analysis of microarray data from a variety of cytokinin-treated samples and used RNA-seq to examine cytokinin-regulated gene expression in Arabidopsis (Arabidopsis thaliana). Microarray meta-analysis using 13 microarray experiments combined with empirically defined filtering criteria identified a set of 226 genes differentially regulated by cytokinin, a subset of which has previously been validated by other methods. RNA-seq validated about 73% of the up-regulated genes identified by this meta-analysis. In silico promoter analysis indicated an overrepresentation of type-B Arabidopsis response regulator binding elements, consistent with the role of type-B Arabidopsis response regulators as primary mediators of cytokinin-responsive gene expression. RNA-seq analysis identified 73 cytokinin-regulated genes that were not represented on the ATH1 microarray. Representative genes were verified using quantitative reverse transcription-polymerase chain reaction and NanoString analysis. Analysis of the genes identified reveals a substantial effect of cytokinin on genes encoding proteins involved in secondary metabolism, particularly those acting in flavonoid and phenylpropanoid biosynthesis, as well as in the regulation of redox state of the cell, particularly a set of glutaredoxin genes. Novel splicing events were found in members of some gene families that are known to play a role in cytokinin signaling or metabolism. The genes identified in this analysis represent a robust set of cytokinin-responsive genes that are useful in the analysis of cytokinin function in plants.

A Systematic Review and Meta-Analysis of Baseline Ohip-Edent Scores.

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Duale, J M J; Patel, Y A; Wu, J; Hyde, T P

2018-03-01

OHIP-EDENT is widely used in the literature to assess Oral-Health-Related-Quality-of-Life (OHRQoL) for edentulous patients. However the normal variance and mean of the baseline OHIP scores has not been reported. It would facilitate critical appraisal of studies if we had knowledge of the normal variation and mean of baseline OHIP-EDENT scores. An established figure for baseline OHIP-EDENT, obtained from a meta-analysis, would simplify comparisons of studies and quantify variations in initial OHRQoL of the trial participants. The aim of this study is to quantify a normal baseline value for pre-operative OHIP-EDENT scores by a systematic review and meta-analysis of the available literature. A systematic literature review was carried. 83 papers were identified that included OHIP-EDENT values. After screening and eligibility assessment, 7 papers were selected and included in the meta-analysis. A meta-analysis for the 7 papers by a random-effect model yielded a mean baseline OHIP-EDENT score of 28.63 with a 95% Confidence intervals from 21.93 to 35.34. A pre-operative baseline OHIP-EDENT has been established by meta-analysis of published papers. This will facilitate the comparison of the initial OHRQoL of one study population to that found elsewhere in the published literature. Copyright© 2018 Dennis Barber Ltd.

Meta-analysis of the relationship between TQM and Business Performance

International Nuclear Information System (INIS)

Ahmad M F; Zakuan N; Jusoh A; Tasir Z; Takala J

2013-01-01

Meta-analysis has been conducted based on 20 previous works from 4,040 firms at 16 countries from Asia, Europe and America. Throughout this paper a meta-analysis, this paper reviews the relationships between TQM and business performance amongst the regions. Meta-analysis result concludes that the average of rc is 0.47; Asia (rc=0.54), America (rc=0.43) and Europe (rc=0.38). The analysis also shows that Asia developed countries have greatest impact of TQM (rc=0.56). However, the analysis of ANOVA and t-test show that there is no significant difference amongst type of country (developed and developing countries) and regions at p=0.05. In addition, the average result of rc 2 is 0.24; Asia (rc 2 =0.33), America (rc 2 =0.22) and Europe (rc 2 =0.15). Meanwhile, rc 2 in developing countries (rc 2 =0.28) are higher than developed countries (rc 2 =0.21).

The Effects of Music on Pain: A Meta-Analysis.

Science.gov (United States)

Lee, Jin Hyung

2016-01-01

Numerous meta-analyses have been conducted on the topic of music and pain, with the latest comprehensive study published in 2006. Since that time, more than 70 randomized controlled trials (RCTs) have been published, necessitating a new and comprehensive review. The aim of this meta-analysis was to examine published RCT studies investigating the effect of music on pain. The present study included RCTs published between 1995 and 2014. Studies were obtained by searching 12 databases and hand-searching related journals and reference lists. Main outcomes were pain intensity, emotional distress from pain, vital signs, and amount of analgesic intake. Study quality was evaluated according to the Cochrane Collaboration guidelines. Analysis of the 97 included studies revealed that music interventions had statistically significant effects in decreasing pain on 0-10 pain scales (MD = -1.13), other pain scales (SMD = -0.39), emotional distress from pain (MD = -10.83), anesthetic use (SMD = -0.56), opioid intake (SMD = -0.24), non-opioid intake (SMD = -0.54), heart rate (MD = -4.25), systolic blood pressure (MD = -3.34), diastolic blood pressure (MD = -1.18), and respiration rate (MD = -1.46). Subgroup and moderator analyses yielded additional clinically informative outcomes. Considering all the possible benefits, music interventions may provide an effective complementary approach for the relief of acute, procedural, and cancer/chronic pain in the medical setting. © the American Music Therapy Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Correlations between MRI and Information Processing Speed in MS: A Meta-Analysis

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S. M. Rao

2014-01-01

Full Text Available Objectives. To examine relationships between conventional MRI measures and the paced auditory serial addition test (PASAT and symbol digit modalities test (SDMT. Methods. A systematic literature review was conducted. Included studies had ≥30 multiple sclerosis (MS patients, administered the SDMT or PASAT, and measured T2LV or brain atrophy. Meta-analysis of MRI/information processing speed (IPS correlations, analysis of MRI/IPS significance tests to account for reporting bias, and binomial testing to detect trends when comparing correlation strengths of SDMT versus PASAT and T2LV versus atrophy were conducted. Results. The 39 studies identified frequently reported only significant correlations, suggesting reporting bias. Direct meta-analysis was only feasible for correlations between SDMT and T2LV (r=-0.45, P<0.001 and atrophy in patients with mixed-MS subtypes (r=-0.54, P<0.001. Familywise Holm-Bonferroni testing found that selective reporting was not the source of at least half of significant results reported. Binomial tests (P=0.006 favored SDMT over PASAT in strength of MRI correlations. Conclusions. A moderate-to-strong correlation exists between impaired IPS and MRI in mixed MS populations. Correlations with MRI were stronger for SDMT than for PASAT. Neither heterogeneity among populations nor reporting bias appeared to be responsible for these findings.

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

NARCIS (Netherlands)

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

2015-01-01

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

Prognostic Value of microRNA-9 in Various Cancers: a Meta-analysis.

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Zhang, Yunyuan; Zhou, Jun; Sun, Meiling; Sun, Guirong; Cao, Yongxian; Zhang, Haiping; Tian, Runhua; Zhou, Lan; Duan, Liang; Chen, Xian; Lun, Limin

2017-07-01

Recently, there are more and more evidences from studies have revealed the association between microRNA-9 (miR-9) expression and outcome in multiple cancers, but inconsistent results have also been reported. It is necessary to rationalize a meta analysis of all available data to clarify the prognostic role of miR-9. Eligible studies were selected through multiple search strategies and the quality was assessed by MOOSE. Data was extracted from studies according to the key statistics index. All analyses were performed using STATA software. Twenty studies were selected in the meta-analysis to evaluate the prognostic role of miR-9 in multiple tumors. MiR-9 expression level was an independent prognostic biomarker for OS in tumor patients using multivariate and univariate analyses. High expression levels of miR-9 was demonstrated to associated with poor overall survival (OS) (HR = 2.23, 95 % CI: 1.56-3.17, P analysis showed that residence region (China and Japan), sample size, cancer type (solid or leukemia), follow-up months and analysis method (qPCR) did not alter the predictive value of miR-9 on OS in various cancers. Furthermore, no significant associations were detected for miR-9 expression and lymph node metastasis or distant metastasis. The present results suggest that promoted miR-9 expression is associated with poor OS in patients with general cancers.

Low circulating ghrelin levels in women with polycystic ovary syndrome: a systematic review and meta-analysis

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Gao, Tian; Wu, Lang; Chang, Fuhou; Cao, Guifang

2016-01-01

Although numerous, human subject studies evaluating the relationship between circulating ghrelin levels and polycystic ovary syndrome (PCOS) risk have yielded inconsistent findings. We aimed to quantitatively assess the association by summarizing all available evidence from human subject studies. The PubMed and Web of Science databases were searched up to February 2015 for eligible studies. Studies were eligible if they reported circulating ghrelin levels in women with PCOS and healthy women controls. A fixed or random-effects model was used to pool risk estimations. Twenty studies including 894 PCOS patients and 574 controls were included in the meta-analysis. The studies had fair methodological quality. The pooling analysis of all available studies revealed that ghrelin levels were significantly lower in PCOS patients than in controls, with standardized mean difference of −0.40 (95% CI: −0.73, −0.08). The significant association persisted in many subgroup strata. However, the heterogeneity across studies was considerable and not eliminated in subgroup analyses. Meta-regression analysis further suggested that the heterogeneity might be relevant to variability in study location, PCOS relevant factors like HOMA-IR ratio, as well as other factors not assessed. In conclusion, our meta-analysis suggested that ghrelin levels were significantly lower in PCOS patients than in controls. Further studies with large sample sizes are warranted to replicate our findings. PMID:26607017

The nature and dimensionality of organizational citizenship behavior: a critical review and meta-analysis.

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Lepine, Jeffrey A; Erez, Amir; Johnson, Diane E

2002-02-01

This article reviews the literature on organizational citizenship behavior (OCB) and its dimensions as proposed by D. W. Organ (1988) and other scholars. Although it is assumed that the behavioral dimensions of OCB are distinct from one another, past research has not assessed this assumption beyond factor analysis. Using meta-analysis, the authors demonstrate that there are strong relationships among most of the dimensions and that the dimensions have equivalent relationships with the predictors (job satisfaction, organizational commitment, fairness, trait conscientiousness, and leader support) most often considered by OCB scholars. Implications of these results are discussed with respect to how the OCB construct should be conceptualized and measured in the future.

Faith-adapted psychological therapies for depression and anxiety: Systematic review and meta-analysis.

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Anderson, Naomi; Heywood-Everett, Suzanne; Siddiqi, Najma; Wright, Judy; Meredith, Jodi; McMillan, Dean

2015-05-01

Incorporating faith (religious or spiritual) perspectives into psychological treatments has attracted significant interest in recent years. However, previous suggestion that good psychiatric care should include spiritual components has provoked controversy. To try to address ongoing uncertainty in this field we present a systematic review and meta-analysis to assess the efficacy of faith-based adaptations of bona fide psychological therapies for depression or anxiety. A systematic review and meta-analysis of randomised controlled trials were performed. The literature search yielded 2274 citations of which 16 studies were eligible for inclusion. All studies used cognitive or cognitive behavioural models as the basis for their faith-adapted treatment (F-CBT). We identified statistically significant benefits of using F-CBT. However, quality assessment using the Cochrane risk of bias tool revealed methodological limitations that reduce the apparent strength of these findings. Whilst the effect sizes identified here were statistically significant, there were relatively a few relevant RCTs available, and those included were typically small and susceptible to significant biases. Biases associated with researcher or therapist allegiance were identified as a particular concern. Despite some suggestion that faith-adapted CBT may out-perform both standard CBT and control conditions (waiting list or "treatment as usual"), the effect sizes identified in this meta-analysis must be considered in the light of the substantial methodological limitations that affect the primary research data. Before firm recommendations about the value of faith-adapted treatments can be made, further large-scale, rigorously performed trials are required. Copyright © 2015 Elsevier B.V. All rights reserved.

Genome-wide meta-analysis identifies 56 bone mineral density loci and reveals 14 loci associated with risk of fracture.

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Estrada, K.; Styrkarsdottir, U.; Evangelou, E.; Hsu, Y.H.; Duncan, E.L.; Ntzani, E.E.; Oei, L.; Albagha, O.M.; Amin, N.; Kemp, J.P.; Koller, D.L.; Li, G.; Liu, C.T.; Minster, R.L.; Moayyeri, A.

2012-01-01

Bone mineral density (BMD) is the most widely used predictor of fracture risk. We performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and east Asian ancestry. We tested the top BMD-associated markers for replication in 50,933 independent subjects and for association with risk of low-trauma fracture in 31,016 individuals with a history of fracture (cases) and 102,444 controls. We ident...

Ataxia Telangiectasia–Mutated Gene Polymorphisms and Acute Normal Tissue Injuries in Cancer Patients After Radiation Therapy: A Systematic Review and Meta-analysis

International Nuclear Information System (INIS)

Dong, Lihua; Cui, Jingkun; Tang, Fengjiao; Cong, Xiaofeng; Han, Fujun

2015-01-01

Purpose: Studies of the association between ataxia telangiectasia–mutated (ATM) gene polymorphisms and acute radiation injuries are often small in sample size, and the results are inconsistent. We conducted the first meta-analysis to provide a systematic review of published findings. Methods and Materials: Publications were identified by searching PubMed up to April 25, 2014. Primary meta-analysis was performed for all acute radiation injuries, and subgroup meta-analyses were based on clinical endpoint. The influence of sample size and radiation injury incidence on genetic effects was estimated in sensitivity analyses. Power calculations were also conducted. Results: The meta-analysis was conducted on the ATM polymorphism rs1801516, including 5 studies with 1588 participants. For all studies, the cut-off for differentiating cases from controls was grade 2 acute radiation injuries. The primary meta-analysis showed a significant association with overall acute radiation injuries (allelic model: odds ratio = 1.33, 95% confidence interval: 1.04-1.71). Subgroup analyses detected an association between the rs1801516 polymorphism and a significant increase in urinary and lower gastrointestinal injuries and an increase in skin injury that was not statistically significant. There was no between-study heterogeneity in any meta-analyses. In the sensitivity analyses, small studies did not show larger effects than large studies. In addition, studies with high incidence of acute radiation injuries showed larger effects than studies with low incidence. Power calculations revealed that the statistical power of the primary meta-analysis was borderline, whereas there was adequate power for the subgroup analysis of studies with high incidence of acute radiation injuries. Conclusions: Our meta-analysis showed a consistency of the results from the overall and subgroup analyses. We also showed that the genetic effect of the rs1801516 polymorphism on acute radiation injuries was

Relationship between nurse psychological empowerment and job satisfaction: A systematic review and meta-analysis.

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Li, Huanhuan; Shi, Ying; Li, Yuan; Xing, Zhuangjie; Wang, Shouqi; Ying, Jie; Zhang, Meiling; Sun, Jiao

2018-06-01

This systematic review and meta-analysis aimed to synthesize and analyse studies that explored the relationship between the psychological empowerment and job satisfaction of nurses. Nurse turnover is an important cause of staff shortage. Job satisfaction is a major predictor of nurse turnover and is connected to the psychological empowerment of nurses. This systematic review and meta-analysis is based on the Joanna Briggs Institute guidelines. A total of 1,572 articles on psychological empowerment and job satisfaction were retrieved from PubMed, PsycINFO, EMBASE and Web of Science. The articles were written in English and published before or by April 2017. Studies on the relationship between psychological empowerment and job satisfaction were summarized. The majority of the included studies revealed that psychological empowerment and job satisfaction are significantly correlated. Only two studies showed that the two factors are not significantly correlated. The result of this meta-analysis is consistent with the results of most studies. One study reported that psychological empowerment partially mediates the structural empowerment and job satisfaction of school health nurses. Two studies, however, did not find that the mediating role of psychological empowerment between structural empowerment and job satisfaction. The results of this review provided evidence for the importance of psychological empowerment for the job satisfaction of among nurses. Exploring the correlation between psychological empowerment and job satisfaction can provide guidelines and recommendation for the development of strategies to promote nurse retention and alleviate nursing shortage. © 2018 John Wiley & Sons Ltd.

Life history of the Harlequin ladybird, Harmonia axyridis; a global meta-analysis

NARCIS (Netherlands)

Raak-van den Berg, C.L.; Hemerik, A.; Werf, van der W.; Jong, de P.W.; Lenteren, van J.C.

2017-01-01

Data collected en used for a meta analysis on life history data of H. axyridis. And the resulting 20 best models for each life history characteristic. Published in the paper: Life history of the Harlequin ladybird, Harmonia axyridis; a global meta-analysis.

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

Science.gov (United States)

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

2017-08-01

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

Improved score statistics for meta-analysis in single-variant and gene-level association studies.

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Yang, Jingjing; Chen, Sai; Abecasis, Gonçalo

2018-06-01

Meta-analysis is now an essential tool for genetic association studies, allowing them to combine large studies and greatly accelerating the pace of genetic discovery. Although the standard meta-analysis methods perform equivalently as the more cumbersome joint analysis under ideal settings, they result in substantial power loss under unbalanced settings with various case-control ratios. Here, we investigate the power loss problem by the standard meta-analysis methods for unbalanced studies, and further propose novel meta-analysis methods performing equivalently to the joint analysis under both balanced and unbalanced settings. We derive improved meta-score-statistics that can accurately approximate the joint-score-statistics with combined individual-level data, for both linear and logistic regression models, with and without covariates. In addition, we propose a novel approach to adjust for population stratification by correcting for known population structures through minor allele frequencies. In the simulated gene-level association studies under unbalanced settings, our method recovered up to 85% power loss caused by the standard methods. We further showed the power gain of our methods in gene-level tests with 26 unbalanced studies of age-related macular degeneration . In addition, we took the meta-analysis of three unbalanced studies of type 2 diabetes as an example to discuss the challenges of meta-analyzing multi-ethnic samples. In summary, our improved meta-score-statistics with corrections for population stratification can be used to construct both single-variant and gene-level association studies, providing a useful framework for ensuring well-powered, convenient, cross-study analyses. © 2018 WILEY PERIODICALS, INC.

Antioxidant therapy for pain relief in patients with chronic pancreatitis: systematic review and meta-analysis.

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Cai, Guo-Hong; Huang, Jing; Zhao, Yan; Chen, Jing; Wu, Huang-Hui; Dong, Yu-Lin; Smith, Howard S; Li, Yun-Qing; Wang, Wen; Wu, Sheng-Xi

2013-01-01

Currently, there is no specific therapy for chronic pancreatitis (CP). The treatment of micronutrient antioxidant therapy for painful CP has been sporadically used for more than 30 years, however, its efficacy are still poorly understood. The purpose of this meta-analysis is to investigate the safety and efficacy of antioxidant therapy for pain relief in patients with CP. University Hospital in China Systematic review and meta-analysis Two authors independently reviewed the search results and extracted data and disagreements were resolved by discussion. Effects were summarized using standardized mean differences (SMDs), weighted mean differences, or odds ratio (OR) according to the suitable effect model. MEDLINE, PsycINFO, Scopus, EMBASE, and the Cochrane Central Register of Controlled Trials  were searched from 1980 through December 2012. Randomized controlled trials (RCTs) that studied antioxidant supplementation for pain relief in patients with CP were analyzed. Nine randomized controlled trials (RCTs) involving 390 patients were included. Overall, there was no association of antioxidant therapy with pain reduction in CP patients (SMD, -0.55; 95% CI, -1.22 to 0.12; P = 0.67). However, antioxidant therapy significantly increased blood levels of antioxidants in CP patients versus the placebo group (SMD, 1.08; 95% CI, 0.74 to 1.43; P pain relief (SMD, -0.93; 95% CI, -1.72 to -0.14; P = 0.02), while the trials in which a single antioxidant was used revealed no significant pain relief (SMD, -0.12; 95% CI, -1.23 to 0.99; P = 0.83) in CP patients. Strong evidence was obtained that the antioxidants increased adverse effects (OR, 6.09; 95% CI, 2.29 to 16.17, P pain relief in CP patients. Measures of total antioxidant status may not help to monitor the efficacy of antioxidant therapy for patients with CP.

The relationship between job satisfaction and health: a meta-analysis.

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Faragher, E B; Cass, M; Cooper, C L

2005-02-01

A vast number of published studies have suggested a link between job satisfaction levels and health. The sizes of the relationships reported vary widely. Narrative overviews of this relationship have been published, but no systematic meta-analysis review has been conducted. A systematic review and meta-analysis of 485 studies with a combined sample size of 267 995 individuals was conducted, evaluating the research evidence linking self-report measures of job satisfaction to measures of physical and mental wellbeing. The overall correlation combined across all health measures was r = 0.312 (0.370 after Schmidt-Hunter adjustment). Job satisfaction was most strongly associated with mental/psychological problems; strongest relationships were found for burnout (corrected r = 0.478), self-esteem(r = 0.429), depression (r = 0.428), and anxiety(r = 0.420). The correlation with subjective physical illness was more modest (r = 0.287). Correlations in excess of 0.3 are rare in this context. The relationships found suggest that job satisfaction level is an important factor influencing the health of workers. Organisations should include the development of stress management policies to identify and eradicate work practices that cause most job dissatisfaction as part of any exercise aimed at improving employee health. Occupational health clinicians should consider counselling employees diagnosed as having psychological problems to critically evaluate their work-and help them to explore ways of gaining greater satisfaction from this important aspect of their life.

Humor styles and personality: A meta-analysis of the relation between humor styles and the Big Five personality traits.

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Mendiburo-Seguel, Andrés; Páez, Darío; Martínez-Sánchez, Francisco

2015-06-01

This research summarizes the knowledge generated in social psychology and positive psychology about the relationship between humor styles, personality and wellbeing. Specifically, a meta-analysis was performed with the results of 15 studies on humor styles measured by the Humor Styles Questionnaire (Martin, Puhlik-Doris, Larsen, Gray & Weir, 2003) in correlation with the personality traits measured by the Big Five Personality model (measured with different scales). Following the steps presented by Rosenthal (1991) for meta-analysis in the case of correlational research, we calculated the total mean r as an indicator of effect size. Results show that affiliative humor has a strong and homogeneous relation to neuroticism and extraversion. The homogeneity and heterogeneity found between variables and possible explanations are discussed in the conclusion. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Association between Obesity and Puberty Timing: A Systematic Review and Meta-Analysis.

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Li, Wenyan; Liu, Qin; Deng, Xu; Chen, Yiwen; Liu, Shudan; Story, Mary

2017-10-24

This systematic review and meta-analysis examined the associations between obesity and puberty timing based on scientific evidence. Eight electronic databases were searched up to February 2017 for eligible studies, and two reviewers screened the articles and extracted the data independently. A total of 11 cohort studies with 4841 subjects met the inclusion criteria. Compared with the group of normal-weight girls, the obese group had more girls with menarche (RR: 1.87, 95% CI: 1.59-2.19, 2 studies). The number of girls with early puberty was significantly higher in the obese group than the normal weight group (RR: 2.44, 95% CI: 1.32-4.52, 5 studies). However, no differences were detected between girls who were obese or normal weight at age of menarche (WMD: -0.53 years, 95% CI: -1.24-0.19, 2 studies). There is no consistent result in the relationship between obesity and timing of pubertal onset in boys. Obesity may contribute to early onset of puberty in girls, while in boys, there is insufficient data. Given the limited number of cohort studies included in this meta-analysis, high-quality studies with strong markers of puberty onset, as well as standardized criteria for defining obesity are needed.

Association between Obesity and Puberty Timing: A Systematic Review and Meta-Analysis

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Wenyan Li

2017-10-01

Full Text Available This systematic review and meta-analysis examined the associations between obesity and puberty timing based on scientific evidence. Eight electronic databases were searched up to February 2017 for eligible studies, and two reviewers screened the articles and extracted the data independently. A total of 11 cohort studies with 4841 subjects met the inclusion criteria. Compared with the group of normal-weight girls, the obese group had more girls with menarche (RR: 1.87, 95% CI: 1.59–2.19, 2 studies. The number of girls with early puberty was significantly higher in the obese group than the normal weight group (RR: 2.44, 95% CI: 1.32–4.52, 5 studies. However, no differences were detected between girls who were obese or normal weight at age of menarche (WMD: −0.53 years, 95% CI: −1.24–0.19, 2 studies. There is no consistent result in the relationship between obesity and timing of pubertal onset in boys. Obesity may contribute to early onset of puberty in girls, while in boys, there is insufficient data. Given the limited number of cohort studies included in this meta-analysis, high-quality studies with strong markers of puberty onset, as well as standardized criteria for defining obesity are needed.

The relationship between adult attachment style and post-traumatic stress symptoms: A meta-analysis

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Woodhouse, S.; Ayers, S.; Field, A. P.

2015-01-01

There is increasing evidence that adult attachment plays a role in the development and perseverance of symptoms of posttraumatic stress disorder (PTSD). This meta-analysis aims to synthesise this evidence and investigate the relationship between adult attachment styles and PTSD symptoms. A random-effects model was used to analyse 46 studies (N = 9268) across a wide range of traumas. Results revealed a medium association between secure attachment and lower PTSD symptoms (ρ =-.27), and a medium...

Aggravated phosphorus limitation on biomass production under increasing nitrogen loading: a meta-analysis.

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Li, Yong; Niu, Shuli; Yu, Guirui

2016-02-01

Nitrogen (N) and phosphorus (P), either individually or in combination, have been demonstrated to limit biomass production in terrestrial ecosystems. Field studies have been extensively synthesized to assess global patterns of N impacts on terrestrial ecosystem processes. However, to our knowledge, no synthesis has been done so far to reveal global patterns of P impacts on terrestrial ecosystems, especially under different nitrogen (N) levels. Here, we conducted a meta-analysis of impacts of P addition, either alone or with N addition, on aboveground (AGB) and belowground biomass production (BGB), plant and soil P concentrations, and N : P ratio in terrestrial ecosystems. Overall, our meta-analysis quantitatively confirmed existing notions: (i) colimitation of N and P on biomass production and (ii) more P limitation in tropical forest than other ecosystems. More importantly, our analysis revealed new findings: (i) P limitation on biomass production was aggravated by N enrichment and (ii) plant P concentration was a better indicator of P limitation than soil P availability. Specifically, P addition increased AGB and BGB by 34% and 13%, respectively. The effect size of P addition on biomass production was larger in tropical forest than grassland, wetland, and tundra and varied with P fertilizer forms, P addition rates, or experimental durations. The P-induced increase in biomass production and plant P concentration was larger under elevated than ambient N. Our findings suggest that the global limitation of P on biomass production will become severer under increasing N fertilizer and deposition in the future. © 2015 John Wiley & Sons Ltd.

Ischiofemoral impingement syndrome: a meta-analysis

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Singer, Adam D.; Subhawong, Ty K.; Jose, Jean; Tresley, Jonathan; Clifford, Paul D. [Jackson Memorial Hospital, Department of Diagnostic Radiology, Section of Musculoskeletal Imaging, Miami, FL (United States)

2015-06-01

The aims of this article are to review the imaging characteristics of ischiofemoral impingement (IFI), summarize measurement thresholds for radiologic diagnosis based on a meta-analysis of the literature and raise awareness among radiologists and clinicians of this entity. A PubMed search restricted to the English language containing the keywords ''ischiofemoral impingement'' and ''quadratus femoris MRI'' was performed, and citations in these articles were also used to identify a total of 27 studies discussing ischiofemoral impingement. After excluding case reports and non-representative studies, there were five remaining articles including 193 hip MRIs of IFI in 154 subjects (133 female, 21 male) and 135 asymptomatic control hip MRIs from 74 subjects (55 female, 19 male). Additionally, we performed a retrospective database search of pelvic and hip MRI reports from our institution including the terms ''quadratus femoris'' or ''ischiofemoral impingement'' from a 9-year period and 24 hip MRIs from 21 patients (18 female, 3 male) with IFI with 5 asymptomatic contralateral control hip MRIs identified. In all, 217 hip MRIs of IFI and 140 control cases were included. A meta-analysis of these hip MRIs was conducted to determine optimal thresholds of the ischiofemoral space (IFS) and quadratus femoris space (QFS) for identifying IFI. Cases of IFI showed significantly smaller IFS and QFS compared to controls (14.91 ± 4.8 versus 26.01 ± 7.98 and 9.57 ± 3.7 versus 15.97 ± 6.07, measured in mm, respectively, p < 0.0001 for both). Pooled analysis revealed that for IFS, using a cutoff of ≤15 mm yielded a sensitivity of 76.9 %, specificity of 81.0 % and overall accuracy of 78.3 %. For QFS, a cutoff of ≤ 10.0 mm resulted in 78.7 % sensitivity, 74.1 % specificity and 77.1 % overall accuracy. IFI is a potential cause of hip pain that can be accurately diagnosed with MRI in conjunction with

Limitations in Using Multiple Imputation to Harmonize Individual Participant Data for Meta-Analysis.

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Siddique, Juned; de Chavez, Peter J; Howe, George; Cruden, Gracelyn; Brown, C Hendricks

2018-02-01

Individual participant data (IPD) meta-analysis is a meta-analysis in which the individual-level data for each study are obtained and used for synthesis. A common challenge in IPD meta-analysis is when variables of interest are measured differently in different studies. The term harmonization has been coined to describe the procedure of placing variables on the same scale in order to permit pooling of data from a large number of studies. Using data from an IPD meta-analysis of 19 adolescent depression trials, we describe a multiple imputation approach for harmonizing 10 depression measures across the 19 trials by treating those depression measures that were not used in a study as missing data. We then apply diagnostics to address the fit of our imputation model. Even after reducing the scale of our application, we were still unable to produce accurate imputations of the missing values. We describe those features of the data that made it difficult to harmonize the depression measures and provide some guidelines for using multiple imputation for harmonization in IPD meta-analysis.

Swimming attendance during childhood and development of asthma: Meta-analysis.

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Valeriani, Federica; Protano, Carmela; Vitali, Matteo; Romano Spica, Vincenzo

2017-05-01

The association between asthma and swimming pool attendance has not been demonstrated and currently there are conflicting results. In order to clarify the association between asthma diagnosis in children and swimming pool attendance, and to assess the consistency of the available epidemiological studies, we completed a literature analysis on the relationship between the exposure to disinfection by-products in indoor swimming pools during childhood and asthma diagnosis. Following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) criteria, a systematic review and meta-analysis was performed by searching MEDLINE via PubMed, TOXNET, and Scopus databases (from inception to 20 April 2015) using the key word "Asthma" together with "swimming pool", "disinfection by-products", "indoor air pollution" and "children". Inclusion criteria were: English language, a complete analytic study design involving a cohort of children (0-16 years), a well-defined definition of exposure, and the presence of data on effect and variance. Studies on in vivo, in vitro or professional and accidental exposure were excluded. After a screening process, seven reports (n = 5851 subjects) were included out of a total of 2928 references. The reported OR of the association between swimming pool attendance and asthma prevalence ranged from 0.58 to 2.30. The present meta-analysis failed to identify a significant difference in asthma development between children attending swimming pools and controls (OR, 1.084; 95% CI: 0.89-1.31). Swimming in childhood does not increase the likelihood of doctor-diagnosed asthma. Based on this meta-analysis review, the association of the disease with indoor pool attendance is still unclear. © 2016 Japan Pediatric Society.

MR diffusion weighted imaging detecting cerebral infarction: a meta-analysis

International Nuclear Information System (INIS)

Yang Junle; Xu Min; Wang Peng; Zhang Qiujuan; Guo Youmin; Liu Min

2008-01-01

Objective: To determine the diagnostic value of diffusion-weighted imaging(DWI) in hyperacute and acute cerebral infarction by using Meta-analysis. Methods: Based on validity criteria for diagnostic research published by the Cochrane Methods Group on Screening and Diagnostic, studies in English and Chinese from 1997 to 2007 were selected from Medline, Cochrane, Springer, Ovid, Elsevier, LWW and CNKI( China National Knowledge Infrastructure). The characteristics of the included articles were appraised and extracted. Statistical analysis was performed with the software Meta-test 0.6 and Comprehensive meta-analysis 2.0. Heterogeneity of the included articles was tested, which was used to select proper effect model to calculate pooled weighted values of sensitivity and specificity and the corresponding 95% CI. Summary receiver operating characteristic (SROC) curve was performed and the area under the curve (Az) was calculated. Publication bias was analyzed by Funnel Plot in Comprehensive Meta- analysis 2.0. A sensitivity analysis was performed. Results: Twelve articles meeting inclusion criteria were analyzed for the value of DWI in hyperacute cerebral infarction. The pooled sensitivity, specificity and diagnostic odds ratio was 92%, 87%, 180.37 respectively, Az=0.9717. Novice is a main factor for total diagnostic effect (Q=4.34, P>0.05). Non-asymmetric funnel plot suggested the publication bias. Fifteen articles meeting inclusion criteria were analyzed for the value of DWI in both hyperacute and acute cerebral infarction (≤ 24 h). The pooled sensitivity, specificity diagnostic odds ratio was 92%, 91%, 623.62 respectively, Az=0.9659. Fixed effects model used in Meta-analysis for database suggested homogeneity (Q=2.70,P>0.05). Nonasymmetric funnel plot suggested the publication bias. Conclusions As a noninvasive method, diffusion-weighted imaging is valuable in detecting hyperacute and acute cerebral infarction. More support from multi-center prospective researches is

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

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

2015-01-01

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

Memory training interventions for older adults: a meta-analysis.

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Gross, Alden L; Parisi, Jeanine M; Spira, Adam P; Kueider, Alexandra M; Ko, Jean Y; Saczynski, Jane S; Samus, Quincy M; Rebok, George W

2012-01-01

A systematic review and meta-analysis of memory training research was conducted to characterize the effect of memory strategies on memory performance among cognitively intact, community-dwelling older adults, and to identify characteristics of individuals and of programs associated with improved memory. The review identified 402 publications, of which 35 studies met criteria for inclusion. The overall effect size estimate, representing the mean standardized difference in pre-post change between memory-trained and control groups, was 0.31 standard deviations (SD; 95% confidence interval (CI): 0.22, 0.39). The pre-post training effect for memory-trained interventions was 0.43 SD (95% CI: 0.29, 0.57) and the practice effect for control groups was 0.06 SD (95% CI: 0.05, 0.16). Among 10 distinct memory strategies identified in studies, meta-analytic methods revealed that training multiple strategies was associated with larger training gains (p=0.04), although this association did not reach statistical significance after adjusting for multiple comparisons. Treatment gains among memory-trained individuals were not better after training in any particular strategy, or by the average age of participants, session length, or type of control condition. These findings can inform the design of future memory training programs for older adults.

Transparent meta-analysis: does aging spare prospective memory with focal vs. non-focal cues?

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Bob Uttl

Full Text Available BACKGROUND: Prospective memory (ProM is the ability to become aware of a previously-formed plan at the right time and place. For over twenty years, researchers have been debating whether prospective memory declines with aging or whether it is spared by aging and, most recently, whether aging spares prospective memory with focal vs. non-focal cues. Two recent meta-analyses examining these claims did not include all relevant studies and ignored prevalent ceiling effects, age confounds, and did not distinguish between prospective memory subdomains (e.g., ProM proper, vigilance, habitual ProM (see Uttl, 2008, PLoS ONE. The present meta-analysis focuses on the following questions: Does prospective memory decline with aging? Does prospective memory with focal vs. non-focal cues decline with aging? Does the size of age-related declines with focal vs. non-focal cues vary across ProM subdomains? And are age-related declines in ProM smaller than age-related declines in retrospective memory? METHODS AND FINDINGS: A meta-analysis of event-cued ProM using data visualization and modeling, robust count methods, and conventional meta-analysis techniques revealed that first, the size of age-related declines in ProM with both focal and non-focal cues are large. Second, age-related declines in ProM with focal cues are larger in ProM proper and smaller in vigilance. Third, age-related declines in ProM proper with focal cues are as large as age-related declines in recall measures of retrospective memory. CONCLUSIONS: The results are consistent with Craik's (1983 proposal that age-related declines on ProM tasks are generally large, support the distinction between ProM proper vs. vigilance, and directly contradict widespread claims that ProM, with or without focal cues, is spared by aging.

Wind power externalities: A meta-analysis

NARCIS (Netherlands)

Mattmann, M.; Logar, I.; Brouwer, R.

2016-01-01

This study presents the first quantitative meta-analysis of the non-market valuation literature on the external effects associated with wind power production. A data set of 60 observations drawn from 32 studies is constructed. The relative economic values of different types of externalities as well

D-cycloserine augmentation in behavioral therapy for obsessive-compulsive disorder: a meta-analysis

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Xia J

2015-04-01

Full Text Available Jing Xia,1 Yanqiu Du,2 Jiyang Han,1 Guo Liu,1 Xumei Wang11Department of Psychiatry, Shengjing Hospital of China Medical University, Heping District Shenyang, Liaoning, People’s Republic of China; 2Department of Medicine, Shenyang Ninth People’s Hospital, Tiexi District, Shenyang, Liaoning, People’s Republic of ChinaObjective: To evaluate the overall effect of D-cycloserine (DCS augmentation on exposure and response prevention (ERP therapy for obsessive-compulsive disorder (OCD.Methods: Clinical studies on the effect of DCS augmentation on ERP therapy for OCD compared to placebo were included for meta analysis. The primary outcome was the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS. Meta-analyses were performed with a random-effect model or a fixed-effect model using the Cochrane Review Manager (RevMan, version 5.2 to calculate the odds ratio and the mean difference, with their corresponding 95% confidence intervals.Results: A total of six studies was included in the current meta-analyses, and their data were extracted. Among them, four were for analyses of DCS and Y-BOCS at midtreatment, six for analysis at posttreatment, and four at 3-month follow-up. Besides, three of the six eligible studies were included in the meta-analysis of the DCS and Clinical Global Impression – Severity Scale at posttreatment, and three in the meta-analysis of DCS and proportions of treatment responders and of subjects attaining clinical remission status criteria at posttreatment. Our meta-analyses do not reveal a significant effect of DCS augmentation in ERP therapy for OCD patients, except when measured at midtreatment. Compared to the placebo group, DCS augmentation did show a trend toward significantly lower/decreased Y-BOCS; when measured at posttreatment and in the subpopulation of DCS taken before some of the ERP sessions, DCS augmentation showed a trend toward significantly lower/decreased Y-BOCS.Conclusion: Our result suggested that with the careful

Family history of diabetes and the risk of gestational diabetes mellitus in Iran: A systematic review and meta-analysis.

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Moosazadeh, Mahmood; Asemi, Zatollah; Lankarani, Kamran B; Tabrizi, Reza; Maharlouei, Najmeh; Naghibzadeh-Tahami, Ahmad; Yousefzadeh, Gholamreza; Sadeghi, Reza; Khatibi, Seyed Reza; Afshari, Mahdi; Khodadost, Mahmoud; Akbari, Maryam

2017-11-01

Gestational diabetes is the most prevalent metabolic disorder being firstly diagnosed during pregnancy. The relationship between the family history of diabetes and the gestational diabetes mellitus (GDM) has been investigated in several primary studies with a number of contradictions in the results. Hence, the purpose of the present study is to determine the relationship between the GDM and the family history of diabetes using the meta-analysis method. All published papers in main national and international databases were systematically searched with some specific keywords to find the related studies between 2000 and 2016. We calculated the odds ratio (OR) with 95% confidence interval (CI) in analysis for each study using a random-effect and Mantel-Haenzel method. We also determined heterogeneity among these 33 articles and their publication bias. We entered 33 relevant studies of 2516 articles into the meta-analysis process including 2697 women with family history of diabetes mellitus as well as 29134 women without. Of them, 954 and 4372 subjects developed GDM respectively. Combining the results of the primary studies using the meta-analysis method, the overall odds ratio of family history for developing GDM was estimated as of 3.46 (95% CI: 2.80-4.27). This meta-analysis study revealed that the family history of diabetes is an important risk factor for the gestational diabetes mellitus. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Exploring factors that influence work analysis data: A meta-analysis of design choices, purposes, and organizational context.

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DuVernet, Amy M; Dierdorff, Erich C; Wilson, Mark A

2015-09-01

Work analysis is fundamental to designing effective human resource systems. The current investigation extends previous research by identifying the differential effects of common design decisions, purposes, and organizational contexts on the data generated by work analyses. The effects of 19 distinct factors that span choices of descriptor, collection method, rating scale, and data source, as well as project purpose and organizational features, are explored. Meta-analytic results cumulated from 205 articles indicate that many of these variables hold significant consequences for work analysis data. Factors pertaining to descriptor choice, collection method, rating scale, and the purpose for conducting the work analysis each showed strong associations with work analysis data. The source of the work analysis information and organizational context in which it was conducted displayed fewer relationships. Findings can be used to inform choices work analysts make about methodology and postcollection evaluations of work analysis information. (c) 2015 APA, all rights reserved).

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

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Pastor, Dena A; Lazowski, Rory A

2018-01-01

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

Divorce and Death: A Meta-Analysis and Research Agenda for Clinical, Social, and Health Psychology.

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Sbarra, David A; Law, Rita W; Portley, Robert M

2011-09-01

Divorce is a relatively common stressful life event that is purported to increase risk for all-cause mortality. One problem in the literature on divorce and health is that it is fragmented and spread across many disciplines; most prospective studies of mortality are based in epidemiology and sociology, whereas most mechanistic studies are based in psychology. This review integrates research on divorce and death via meta-analysis and outlines a research agenda for better understanding the potential mechanisms linking marital dissolution and risk for all-cause mortality. Random effects meta-analysis with a sample of 32 prospective studies (involving more than 6.5 million people, 160,000 deaths, and over 755,000 divorces in 11 different countries) revealed a significant increase in risk for early death among separated/divorced adults in comparison to their married counterparts. Men and younger adults evidenced significantly greater risk for early death following marital separation/divorce than did women and older adults. Quantification of the overall effect size linking marital separation/divorce to risk for early death reveals a number of important research questions, and this article discusses what remains to be learned about four plausible mechanisms of action: social selection, resource disruptions, changes in health behaviors, and chronic psychological distress. © Association for Psychological Science 2011.

Reevaluation of Meta-analysis on prophylactic drug management for recurrence of febrile seizures

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Huan LIAO

2015-08-01

Full Text Available Objective To explore the efficiency and safety of drugs to prevent the recurrence of febrile seizures (FS.  Methods Relevant literatures were searched via PubMed, EMBASE/SCOPUS, EBSCO-CINAHL, Web of Science, Cochrane Database of Systematic Reviews from December 1997 to November 2014 using the following keywords: febrile seizure OR febrile convulsion, recurrence, prevention OR prophylaxis, medicine OR medication. Publication type was limited to Meta-analysis. Extract the relevant information of Meta-analysis, such as characteristics of objects, types of study design, number of clinical trials, number of cases, search strategies, databases, information of methodology (methods of randomization, concealment, blinding, withdrawal and exit, follow-up time, heterogeneity analysis, subgroup analysis and outcome assessment, etc. Quality of Reporting of Meta-analyses (QUOROM and Oxman-Guyatt Overview Quality Assessment Questionnaire (OQAQ were used to assess the quality of included Meta-analyses. Jadad decision was used to assess inclusion and exclusion criteria, search strategies, effectiveness evaluation, data extraction and data analysis, to explore reliable evidence of evidence-based medicine.  Results Eventually, four Meta-analyses were included after screening of all the literatures that can be searched out. Among those Meta-analyses, the Meta-analysis of Offringa and Newton (2012 was relatively more reliable. The results suggesed that no clinically important benefits were found in administering intermittent oral or rectal diazepam, oral phenobarbitone, phenytoin, valproate, pyridoxine, buprofen, diclofenac and acetominophen to children with FE. Only one clinical trial reported that intermittent oral clobazam could reduce the recurrence of FE in comparing with placebo at 6-month follow-up (RR = 0.360, 95% CI: 0.200-0.640; P = 0.000, but it should be verified by more randomized controlled trials (RCTs. Among 4 Meta-analyses included in this study

Risk of Occupational Accidents in Workers with Obstructive Sleep Apnea: Systematic Review and Meta-analysis

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Garbarino, Sergio; Guglielmi, Ottavia; Sanna, Antonio; Mancardi, Gian Luigi; Magnavita, Nicola

2016-01-01

Study Objectives: Obstructive sleep apnea (OSA) is the single most important preventable medical cause of excessive daytime sleepiness (EDS) and driving accidents. OSA may also adversely affect work performance through a decrease in productivity, and an increase in the injury rate. Nevertheless, no systematic review and meta-analysis of the relationship between OSA and work accidents has been performed thus far. Methods: PubMed, PsycInfo, Scopus, Web of Science, and Cochrane Library were searched. Out of an initial list of 1,099 papers, 10 studies (12,553 participants) were eligible for our review, and 7 of them were included in the meta-analysis. The overall effects were measured by odds ratios (OR) and 95% confidence intervals (CI). An assessment was made of the methodological quality of the studies. Moderator analysis and funnel plot analysis were used to explore the sources of between-study heterogeneity. Results: Compared to controls, the odds of work accident was found to be nearly double in workers with OSA (OR = 2.18; 95% CI = 1.53–3.10). Occupational driving was associated with a higher effect size. Conclusions: OSA is an underdiagnosed nonoccupational disease that has a strong adverse effect on work accidents. The nearly twofold increased odds of work accidents in subjects with OSA calls for workplace screening in selected safety-sensitive occupations. Commentary: A commentary on this article appears in this issue on page 1171. Citation: Garbarino S, Guglielmi O, Sanna A, Mancardi GL, Magnavita N. Risk of occupational accidents in workers with obstructive sleep apnea: systematic review and meta-analysis. SLEEP 2016;39(6):1211–1218. PMID:26951401

A meta-analysis of the association between TNF-α -308G>A polymorphism and type 2 diabetes mellitus in Han Chinese population.

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Zheng-hui Liu

Full Text Available OBJECTIVE: A meta-analysis was applied to evaluate the associations between tumor necrosis factor-α (TNF-α -308G>A (rs1800629 polymorphism and type 2 diabetes mellitus (T2DM. METHODS: Hardy-Weinberg equilibrium (HWE was employed to test genetic equilibrium among the genotypes of the selected literature. Power analysis was performed with the Power and Sample Size Calculation (PS program. A fixed or random effect model was used on the basis of heterogeneity. Publication bias was quantified and examined with the Begg's funnel plot test and Egger's linear regression test. The meta-analysis was performed with Review Manager 5.1 and Stata 11.0. RESULTS: There were 10 studies including 1425 T2DM patients and 1116 healthy control subjects involved in this meta-analysis. No significant publication bias was found in the studies. The pooled ORs (95% CIs for TNF-α -308G>A of A vs. G allele and GA+AA vs. GG genotype were 1.63 (1.17-2.25 and 1.47 (1.17-1.85, respectively. CONCLUSION: This meta-analysis result suggested that TNF-α -308G>A polymorphism was strongly associated with T2DM risk, and A allele at this locus might be a susceptibility allele for the development of T2DM in Han Chinese population.

Comparison of Maladaptive Meta Cognition Beliefs among Substance Dependents and Non-Dependents

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Omid Saed

2011-05-01

Full Text Available Introduction: The aim of present research was the comparison of maladaptive meta cognition beliefs among substance abusers and non abusers. Methods: For this purpose 70 substance abusers and 70 individuals from the general population by purposive sampling participated in this research and responded to meta cognition questionnaire. For analysis data multiple analysis of variance (MANOVA and discriminant analysis were run. Results: MANOVA revealed that there was significant difference in linier combination of dependent variables (meta cognitive beliefs among two groups also, analysis of dependent variables lonely showed that two groups were significantly different in Positive meta cognitive beliefs, "Negative meta cognitive beliefs", "lack of cognitive confidence", "need to control of thoughts", and "cognitive self-consciousness". Also, the discriminant analysis indicated that three meta-cognitive factors included “negative meta cognitive beliefs", "need to control of thoughts" and "cognitive self-consciousness" were significant predictors to discriminate substance abusers. Conclusion: With consideration of the results it can be concluded that substance abusers have more maladaptive beliefs and these maladaptive beliefs can lead to susceptibility toward substance abuse and staying in this disorder. It is hoped that psychotherapists can be more useful in treating and staying in this research.

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

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

2010-01-01

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

REAL-TIME ENERGY INFORMATION AND CONSUMER BEHAVIOR: A META-ANALYSIS AND FORECAST

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The meta-analysis of literature and program results will shed light on potential causes of study-to-study variation in information feedback programs and trials. Outputs from the meta-analysis, such as price elasticity, will be used in NEMS to estimate the impact of a nation...

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

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Apugliese, Andrew; Lewis, Scott E.

2017-01-01

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

Attentional Bias for Emotional Stimuli in Borderline Personality Disorder: A Meta-Analysis.

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Kaiser, Deborah; Jacob, Gitta A; Domes, Gregor; Arntz, Arnoud

2016-01-01

In borderline personality disorder (BPD), attentional bias (AB) to emotional stimuli may be a core component in disorder pathogenesis and maintenance. 11 emotional Stroop task (EST) studies with 244 BPD patients, 255 nonpatients (NPs) and 95 clinical controls and 4 visual dot-probe task (VDPT) studies with 151 BPD patients or subjects with BPD features and 62 NPs were included. We conducted two separate meta-analyses for AB in BPD. One meta-analysis focused on the EST for generally negative and BPD-specific/personally relevant negative words. The other meta-analysis concentrated on the VDPT for negative and positive facial stimuli. There is evidence for an AB towards generally negative emotional words compared to NPs (standardized mean difference, SMD = 0.311) and to other psychiatric disorders (SMD = 0.374) in the EST studies. Regarding BPD-specific/personally relevant negative words, BPD patients reveal an even stronger AB than NPs (SMD = 0.454). The VDPT studies indicate a tendency towards an AB to positive facial stimuli but not negative stimuli in BPD patients compared to NPs. The findings rather reflect an AB in BPD to generally negative and BPD-specific/personally relevant negative words rather than an AB in BPD towards facial stimuli, and/or a biased allocation of covert attentional resources to negative emotional stimuli in BPD and not a bias in focus of visual attention. Further research regarding the role of childhood traumatization and comorbid anxiety disorders may improve the understanding of these underlying processes. © 2016 The Author(s) Published by S. Karger AG, Basel.

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

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

2017-01-01

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

Global meta-analysis of transcriptomics studies.

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José Caldas

Full Text Available Transcriptomics meta-analysis aims at re-using existing data to derive novel biological hypotheses, and is motivated by the public availability of a large number of independent studies. Current methods are based on breaking down studies into multiple comparisons between phenotypes (e.g. disease vs. healthy, based on the studies' experimental designs, followed by computing the overlap between the resulting differential expression signatures. While useful, in this methodology each study yields multiple independent phenotype comparisons, and connections are established not between studies, but rather between subsets of the studies corresponding to phenotype comparisons. We propose a rank-based statistical meta-analysis framework that establishes global connections between transcriptomics studies without breaking down studies into sets of phenotype comparisons. By using a rank product method, our framework extracts global features from each study, corresponding to genes that are consistently among the most expressed or differentially expressed genes in that study. Those features are then statistically modelled via a term-frequency inverse-document frequency (TF-IDF model, which is then used for connecting studies. Our framework is fast and parameter-free; when applied to large collections of Homo sapiens and Streptococcus pneumoniae transcriptomics studies, it performs better than similarity-based approaches in retrieving related studies, using a Medical Subject Headings gold standard. Finally, we highlight via case studies how the framework can be used to derive novel biological hypotheses regarding related studies and the genes that drive those connections. Our proposed statistical framework shows that it is possible to perform a meta-analysis of transcriptomics studies with arbitrary experimental designs by deriving global expression features rather than decomposing studies into multiple phenotype comparisons.

Dietary patterns and colorectal cancer risk: a meta-analysis.

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Feng, Yu-Liang; Shu, Long; Zheng, Pei-Fen; Zhang, Xiao-Yan; Si, Cai-Juan; Yu, Xiao-Long; Gao, Wei; Zhang, Lun

2017-05-01

The analysis of dietary patterns has recently drawn considerable attention as a method of investigating the association between the overall whole diet and the risk of colorectal cancer. However, the results have yielded conflicting findings. Here, we carried out a meta-analysis to identify the association between dietary patterns and the risk of colorectal cancer. A total of 40 studies fulfilled the inclusion criteria and were included in this meta-analysis. The highest category of 'healthy' dietary pattern compared with the lowest category was apparently associated with a decreased risk for colorectal cancer [odds ratio (OR)=0.75; confidence interval (CI): 0.68-0.83; Pcolorectal cancer was shown for the highest compared with the lowest category of a 'western-style' dietary pattern (OR=1.40; CI: 1.26-1.56; Pcolorectal cancer in the highest compared with the lowest category of 'alcohol-consumption' pattern (OR=1.44; CI: 1.13-1.82; P=0.003). The results of this meta-analysis indicate that a 'healthy' dietary pattern may decrease the risk of colorectal cancer, whereas 'western-style' and 'alcohol-consumption' patterns may increase the risk of colorectal cancer.

Development and validation of MIX: comprehensive free software for meta-analysis of causal research data

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Ikeda Noriaki

2006-10-01

Full Text Available Abstract Background Meta-analysis has become a well-known method for synthesis of quantitative data from previously conducted research in applied health sciences. So far, meta-analysis has been particularly useful in evaluating and comparing therapies and in assessing causes of disease. Consequently, the number of software packages that can perform meta-analysis has increased over the years. Unfortunately, it can take a substantial amount of time to get acquainted with some of these programs and most contain little or no interactive educational material. We set out to create and validate an easy-to-use and comprehensive meta-analysis package that would be simple enough programming-wise to remain available as a free download. We specifically aimed at students and researchers who are new to meta-analysis, with important parts of the development oriented towards creating internal interactive tutoring tools and designing features that would facilitate usage of the software as a companion to existing books on meta-analysis. Results We took an unconventional approach and created a program that uses Excel as a calculation and programming platform. The main programming language was Visual Basic, as implemented in Visual Basic 6 and Visual Basic for Applications in Excel 2000 and higher. The development took approximately two years and resulted in the 'MIX' program, which can be downloaded from the program's website free of charge. Next, we set out to validate the MIX output with two major software packages as reference standards, namely STATA (metan, metabias, and metatrim and Comprehensive Meta-Analysis Version 2. Eight meta-analyses that had been published in major journals were used as data sources. All numerical and graphical results from analyses with MIX were identical to their counterparts in STATA and CMA. The MIX program distinguishes itself from most other programs by the extensive graphical output, the click-and-go (Excel interface, and the

Lead and Conduct Problems: A Meta-Analysis

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

2010-01-01

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

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

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

2018-05-18

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

Induced abortion rate in Iran: a meta-analysis.

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Motaghi, Zahra; Poorolajal, Jalal; Keramat, Afsaneh; Shariati, Mohammad; Yunesian, Masud; Masoumi, Seyyedeh Zahra

2013-10-01

About 44 million induced abortions take place worldwide annually, of which 50% are unsafe. The results of studies investigated the induced abortion rate in Iran are inconsistent. The aim of this meta-analysis was to estimate the incidence rate of induced abortion in Iran. National and international electronic databases, as well as conference databases until July 2012 were searched. Reference lists of articles were screened and the studies' authors were contacted for additional unpublished studies. Cross-sectional studies addressing induced abortion in Iran were included in this meta-analysis. The primary outcome of interest was the induced abortion rate (the number of abortions per 1000 women aged 15-44 years in a year) or the ratio (the number of abortions per 100 live births in a year). The secondary outcome of interest was the prevalence of unintended pregnancies (the number of mistimed, unplanned, or unwanted pregnancies per total pregnancies). Data were analyzed using random effect models. Of 603 retrieved studies, using search strategy, 10 studies involving 102,394 participants were eventually included in the meta-analysis. The induced abortion rate and ratio were estimated as 8.9 per 1000 women aged 15-44 years (95% CI: 5.46, 12.33) and 5.34 per 100 live births (95% CI: 3.61, 7.07), respectively. The prevalence of unintended pregnancy was estimated as 27.94 per 100 pregnant women (95% CI: 23.46, 32.42). The results of this meta-analysis helped a better understanding of the incidence of induced abortion in Iran compared to the other developing countries in Asia. However, additional sources of data on abortion other than medical records and survey studies are needed to estimate the true rate of unsafe abortion in Iran.

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

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Mila, A L; Ngugi, H K

2011-01-01

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

Meta-analysis of factor V Leiden and ischemic stroke in young adults: the importance of case ascertainment.

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Hamedani, Ali G; Cole, John W; Mitchell, Braxton D; Kittner, Steven J

2010-08-01

The factor V Leiden mutation is associated with ischemic stroke in children but not in adults. Whether it is associated with ischemic stroke in young adults, however, is uncertain. To address this issue, we performed a meta-analysis of 18 case-control studies of ischemic stroke in adults 50 years of age and younger published before June 2009. Across all studies, factor V Leiden was detected in 154 of 2045 cases (7.5%) and 217 of 5307 controls (4.1%), yielding a fixed-effect odds ratio of 2.00 (95% CI, 1.59-2.51). However, further analyses revealed substantial heterogeneity among these studies (P=0.005 for Q-test of heterogeneity). Hypothesizing that this heterogeneity could be related to differences among studies in case selection criteria, we stratified the meta-analysis into studies for which case samples were enriched or not enriched to include cases having an increased likelihood of prothrombotic genetic involvement ("selected" ischemic stroke studies, n=9) and those that recruited cases from consecutive neurology referrals or hospitalizations ("unselected" ischemic stroke studies, n=8). Among the 9 "selected" ischemic stroke studies, factor V Leiden was more strongly associated with stroke (OR, 2.73; 95% CI, 1.98-3.75), whereas among the 8 "unselected" ischemic stroke studies, the association between factor V Leiden and stroke was substantially weaker (OR, 1.40; 95% CI, 0.998-1.95). This difference was found to be statistically significant (P=0.003 for Woolf test for heterogeneity). We conclude that factor V Leiden is associated with ischemic stroke in young adults, particularly in patient populations in which there is an increased clinical suspicion of prothrombotic state.

A Meta-Analysis of Cross Sectional Studies Investigating Language in Maltreated Children

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Lum, Jarrad A. G.; Powell, Martine; Timms, Lydia; Snow, Pamela

2015-01-01

Purpose: In this review article, meta-analysis was used to summarize research investigating language skills in maltreated children. Method: A systematic search of published studies was undertaken. Studies were included in the meta-analysis if they investigated language skills in groups comprising maltreated and nonmaltreated children. Studies were…

Meta-analysis of differentiating mouse embryonic stem cell gene expression kinetics reveals early change of a small gene set.

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Clive H Glover

2006-11-01

Full Text Available Stem cell differentiation involves critical changes in gene expression. Identification of these should provide endpoints useful for optimizing stem cell propagation as well as potential clues about mechanisms governing stem cell maintenance. Here we describe the results of a new meta-analysis methodology applied to multiple gene expression datasets from three mouse embryonic stem cell (ESC lines obtained at specific time points during the course of their differentiation into various lineages. We developed methods to identify genes with expression changes that correlated with the altered frequency of functionally defined, undifferentiated ESC in culture. In each dataset, we computed a novel statistical confidence measure for every gene which captured the certainty that a particular gene exhibited an expression pattern of interest within that dataset. This permitted a joint analysis of the datasets, despite the different experimental designs. Using a ranking scheme that favored genes exhibiting patterns of interest, we focused on the top 88 genes whose expression was consistently changed when ESC were induced to differentiate. Seven of these (103728_at, 8430410A17Rik, Klf2, Nr0b1, Sox2, Tcl1, and Zfp42 showed a rapid decrease in expression concurrent with a decrease in frequency of undifferentiated cells and remained predictive when evaluated in additional maintenance and differentiating protocols. Through a novel meta-analysis, this study identifies a small set of genes whose expression is useful for identifying changes in stem cell frequencies in cultures of mouse ESC. The methods and findings have broader applicability to understanding the regulation of self-renewal of other stem cell types.

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

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

2013-01-01

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

An improved method for bivariate meta-analysis when within-study correlations are unknown.

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Hong, Chuan; D Riley, Richard; Chen, Yong

2018-03-01

Multivariate meta-analysis, which jointly analyzes multiple and possibly correlated outcomes in a single analysis, is becoming increasingly popular in recent years. An attractive feature of the multivariate meta-analysis is its ability to account for the dependence between multiple estimates from the same study. However, standard inference procedures for multivariate meta-analysis require the knowledge of within-study correlations, which are usually unavailable. This limits standard inference approaches in practice. Riley et al proposed a working model and an overall synthesis correlation parameter to account for the marginal correlation between outcomes, where the only data needed are those required for a separate univariate random-effects meta-analysis. As within-study correlations are not required, the Riley method is applicable to a wide variety of evidence synthesis situations. However, the standard variance estimator of the Riley method is not entirely correct under many important settings. As a consequence, the coverage of a function of pooled estimates may not reach the nominal level even when the number of studies in the multivariate meta-analysis is large. In this paper, we improve the Riley method by proposing a robust variance estimator, which is asymptotically correct even when the model is misspecified (ie, when the likelihood function is incorrect). Simulation studies of a bivariate meta-analysis, in a variety of settings, show a function of pooled estimates has improved performance when using the proposed robust variance estimator. In terms of individual pooled estimates themselves, the standard variance estimator and robust variance estimator give similar results to the original method, with appropriate coverage. The proposed robust variance estimator performs well when the number of studies is relatively large. Therefore, we recommend the use of the robust method for meta-analyses with a relatively large number of studies (eg, m≥50). When the

The Relationship between Teacher Support and Students' Academic Emotions: A Meta-Analysis

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Hao Lei

2018-01-01

Full Text Available This meta-analysis examines the association between teacher support and students' academic emotions [both positive academic emotions (PAEs and negative academic emotions (NAEs] and explores how student characteristics moderate these relationships. We identified 65 primary studies with 58,368 students. The results provided strong evidence linking teacher support and students' academic emotions. Furthermore, students' culture, age, and gender moderated these links. The correlation between teacher support and PAEs was stronger for Western European and American students than for East Asian students, while the correlation between teacher support and NAEs was stronger for East Asian students than for Western European and American students. Also, the correlation between teacher support and PAEs was strong among university students and weaker among middle school students, compared to other students. The correlation between teacher support and NAEs was stronger for middle school students and for female students, compared to other students.

A Bayesian Nonparametric Meta-Analysis Model

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

2015-01-01

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

Dyadic Interracial Interactions: A Meta-Analysis

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Toosi, Negin R.; Babbitt, Laura G.; Ambady, Nalini; Sommers, Samuel R.

2012-01-01

This meta-analysis examined over 40 years of research on interracial interactions by exploring 4 types of outcomes: explicit attitudes toward interaction partners, participants' self-reports of their own emotional state, nonverbal or observed behavior, and objective measures of performance. Data were collected from 108 samples (N = 12,463)…

Periodontal disease treatment and risk of preterm birth: a systematic review and meta-analysis.

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Rosa, Maria Inês da; Pires, Patrícia Duarte Simões; Medeiros, Lidia Rosi; Edelweiss, Maria Isabel; Martínez-Mesa, Jeovany

2012-10-01

The events leading to preterm birth are still not completely understood. A quantitative systematic review was performed to estimate the effects of periodontal care during pregnancy on preventing preterm birth and low birth weight. The meta-analysis included randomized trials with pregnant women with a diagnosis of periodontal disease before 20 weeks of gestation. Relative risk (RR) with 95% confidence intervals (95%CI) was calculated. We evaluated the reduction in preterm and low birth weight. Thirteen trials were included, comparing 3,576 women in intervention groups with 3,412 women receiving usual care. The meta-analysis of the effects of periodontal disease treatment during pregnancy indicated a non-significant reduction in preterm births (RR = 0.90; 95%CI: 0.68-1.19) and low birth weights (RR = 0.92; 95%CI: 0.71-1.20). The creation and examination of a funnel plot revealed clear evidence of publication bias. In summary, primary periodontal care during pregnancy cannot be considered an efficient way of reducing the incidence of preterm birth.

Biological variability in biomechanical engineering research: Significance and meta-analysis of current modeling practices.

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Cook, Douglas; Julias, Margaret; Nauman, Eric

2014-04-11

Biological systems are characterized by high levels of variability, which can affect the results of biomechanical analyses. As a review of this topic, we first surveyed levels of variation in materials relevant to biomechanics, and compared these values to standard engineered materials. As expected, we found significantly higher levels of variation in biological materials. A meta-analysis was then performed based on thorough reviews of 60 research studies from the field of biomechanics to assess the methods and manner in which biological variation is currently handled in our field. The results of our meta-analysis revealed interesting trends in modeling practices, and suggest a need for more biomechanical studies that fully incorporate biological variation in biomechanical models and analyses. Finally, we provide some case study example of how biological variability may provide valuable insights or lead to surprising results. The purpose of this study is to promote the advancement of biomechanics research by encouraging broader treatment of biological variability in biomechanical modeling. Copyright © 2014 Elsevier Ltd. All rights reserved.

High-intensity interval training in patients with lifestyle-induced cardiometabolic disease: a systematic review and meta-analysis.

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Weston, Kassia S; Wisløff, Ulrik; Coombes, Jeff S

2014-08-01

Cardiorespiratory fitness (CRF) is a strong determinant of morbidity and mortality. In athletes and the general population, it is established that high-intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) in improving CRF. This is a systematic review and meta-analysis to quantify the efficacy and safety of HIIT compared to MICT in individuals with chronic cardiometabolic lifestyle diseases. The included studies were required to have a population sample of chronic disease, where poor lifestyle is considered as a main contributor to the disease. The procedural quality of the studies was assessed by use of a modified Physiotherapy Evidence Base Database (PEDro) scale. A meta-analysis compared the mean difference (MD) of preintervention versus postintervention CRF (VO2peak) between HIIT and MICT. 10 studies with 273 patients were included in the meta-analysis. Participants had coronary artery disease, heart failure, hypertension, metabolic syndrome and obesity. There was a significantly higher increase in the VO2peak after HIIT compared to MICT (MD 3.03 mL/kg/min, 95% CI 2.00 to 4.07), equivalent to 9.1%. HIIT significantly increases CRF by almost double that of MICT in patients with lifestyle-induced chronic diseases. 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.

A meta-analysis of the association of serum ischaemia-modified albumin levels with human hypothyroidism and hyperthyroidism.

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Reddy, Varikasuvu Seshadri; Bukke, Suman; Mahato, Khageshwar; Kumar, Vinod; Reddy, Netala Vasudeva; Munikumar, Manne; Vodelu, Bramahanapally

2017-02-28

Serum levels of ischaemia-modified albumin (IMA) have been studied as a novel and simple measure of oxidative stress (OXS) in different thyroid pathologies. However, results of available studies in the literature were not consistent. This meta-analysis was attempted to quantify the overall effect size for serum IMA levels in human hypothyroidism (HT) and hyperthyroidism (HYT) and to study its associations with the thyroid profile. Databases of PubMed/Medline, EMBASE, Google Scholar, Web of Science and Science Direct were searched for articles. Data on serum IMA levels in HT, HYT patients and euthyroid controls were extracted to compute standardized mean differences (SMD) by the random-effects model. The associations between IMA and thyroid profile were computed by the meta-analysis of correlation coefficients. IMA levels in HT patients (SMD=1.12; Z=2.76; P=0.006) and HYT patients (SMD=1.64; Z=2.57; P=0.01) were significantly higher than in euthyroid controls and the thyroid treatment showed a favourble effect on serum IMA levels. There were strong and significant correlations between IMA and hormonal status in HT and HYT groups. This meta-analysis showing increased IMA level in both HT and HYT patients and its association with thyroid profile suggests that serum IMA could be used as a simple measure of increased OXS in thyroid dysfunction. © 2017 The Author(s).

Time perspective and environmental engagement: a meta-analysis.

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Milfont, Taciano L; Wilson, Jessie; Diniz, Pollyane

2012-01-01

Environmental issues entail both a social conflict (private vs. public interests) and a temporal conflict (short- vs. long-term interests). This paper focuses on the role temporal concerns play in influencing environmental engagement by quantitatively integrating results of studies that assessed the associations between time perspective and proenvironmental attitudes and behaviors. The meta-analysis included a total of 19 independent samples and 6,301 participants from seven countries (Australia, Brazil, Germany, Mexico, New Zealand, Norway, and the United States). Results showed that the associations between time perspective and proenvironmental behaviors were higher than those for proenvironmental attitudes. Supporting predictions, the associations between future time perspective and proenvironmental behaviors were strong and nontrivial compared to those for the combined past-present time perspective. The findings indicate that future time perspective seems to play an important role in influencing individuals' attitudes and behaviors towards the environment. Implications of the findings for theory and practice are discussed.

Enhancing well-being and alleviating depressive symptoms with positive psychology interventions: A practice-friendly meta-analysis

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Sin, NL; Lyubomirsky, S

2009-01-01

Do positive psychology interventions - that is, treatment methods or intentional activities aimed at cultivating positive feelings, positive behaviors, or positive cognitions - enhance well-being and ameliorate depressive symptoms? A meta-analysis of 51 such interventions with 4,266 individuals was conducted to address this question and to provide practical guidance to clinicians. The results revealed that positive psychology interventions do indeed significantly enhance well-being (mean r=.2...

Thyroid Cytology in India: Contemporary Review and Meta-analysis.

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Agarwal, Shipra; Jain, Deepali

2017-11-01

Fine-needle aspiration cytology (FNAC) is a screening test for triaging thyroid nodules, aiding in subsequent clinical management. However, the advantages have been overshadowed by the multiplicity of reporting systems and a wide range of nomenclature used. The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was formulated in 2007, to give the world a uniform thyroid cytology reporting system, facilitating easy interpretation by the clinicians. Here, we review the status of thyroid FNAC in India in terms of various reporting systems used including a meta-analysis of the previously published data. An extensive literature search was performed using internet search engines. The reports with detailed classification system used in thyroid cytology were included. The meta-analysis of published data was compared with the implied risk of malignancy by TBSRTC. More than 50 studies were retrieved and evaluated. TBSRTC is currently the most widely used reporting system with different studies showing good efficacy and interobserver concordance. Ancillary techniques have, as of now, limited applicability and acceptability in thyroid cytology in India. Twenty-eight published articles met the criteria for inclusion in the meta-analysis. When compared with TBSRTC recommendations, the meta-analysis showed a higher risk of malignancy for categories I and III. Thyroid FNAC is practiced all over India. TBSRTC has found widespread acceptance, with most institutions using this system for routine thyroid cytology reporting. However, reasons for a high malignancy risk for categories I and III need to be looked into. Various possible contributing factors are discussed in the review.

Methicillin resistant Staphylococcus aureus in Ethiopia: a meta-analysis.

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Eshetie, Setegn; Tarekegn, Fentahun; Moges, Feleke; Amsalu, Anteneh; Birhan, Wubet; Huruy, Kahsay

2016-11-21

The burden of methicillin resistant Staphylococcus aureus is a major public health concern worldwide; however the overall epidemiology of multidrug resistant strains is neither coordinated nor harmonized, particularly in developing countries including Ethiopia. Therefore, the aim of this meta-analysis was to assess the burden of methicillin resistant Staphylococcos aureus and its antibiotic resistance pattern in Ethiopia at large. PubMed, Google Scholar, and lancet databases were searched and a total of 20 studies have been selected for meta-analysis. Six authors have independently extracts data on the prevalence of methicillin resistant Staphylococcus aureus among clinical isolates of Staphylococcus aureus. Statistical analysis was achieved by using Open meta-analyst (version 3.13) and Comprehensive meta-analysis (version 3.3) softwares. The overall prevalence of methicillin resistant Staphylococcus aureus and its antibiotic resistance pattern were pooled by using the forest plot, table and figure with 95% CI. The pooled prevalence of methicillin resistant Staphylococcus aureus was 32.5% (95% CI, 24.1 to 40.9%). Moreover, methicillin resistant Staphylococcus aureus strains were found to be highly resistant to penicillin, ampicillin, erythromycin, and amoxicillin, with a pooled resistance ratio of 99.1, 98.1, 97.2 and 97.1%, respectively. On the other hand, comparably low levels of resistance ratio were noted to vancomycin, 5.3%. The overall burden of methicillin resistant Staphylococcus aureus is considerably high, besides these strains showed extreme resistance to penicillin, ampicillin, erythromycin and amoxicillin. In principle, appropriate use of antibiotics, applying safety precautions are the key to reduce the spread of multidrug resistant strains, methicillin resistant Staphylococcus aureus in particular.

Prognostic role of microRNA-150 in various carcinomas: a meta-analysis

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Wang W

2016-03-01

Full Text Available Wei Wang, Xinshuai Wang, Yali Zhang, Dan Wang, Hui Gao, Lijuan Wang, Shegan Gao Henan Key Laboratory of Cancer Epigenetics, Cancer Institute, The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, Luoyang, Henan, People’s Republic of China Objective: MicroRNA-150 (miR-150 was revealed to be an attractive prognostic biomarker in recent studies. However, the prognostic significance of miR-150 expression in cancer remains inconclusive. The aim of this study was to summarize the global predicting role of miR-150 in survival in patients with various carcinomas.Methods: Eligible studies were identified through multiple search strategies. Data were extracted from the studies by investigating the relationship between miR-150 expression and survival in patients with cancer. A meta-analysis of the hazard ratio (HR was then performed to evaluate the prognostic role of miR-150 in different tumors. Pooled HRs of miR-150 for overall survival and progression-free survival were calculated to measure the effect of miR-150 expression on prognosis.Results: This meta-analysis included nine published studies concerning various carcinomas. Our results indicate that an elevated miR-150 expression is associated with an enhanced overall survival in the digestive tract cancer subgroup (HR =0.57, 95% confidence interval [CI]: 0.37–0.90 and a poor progression-free survival in various cancers (HR =3.08, 95% CI: 2.00–4.75.Conclusion: miR-150 may have the potential to become a new useful prognostic factor to monitor cancer prognosis and progression. However, given the current insufficient relevant data, further clinical studies are needed. Keywords: microRNA-150, carcinomas, prognosis, meta-analysis

Cruciferous vegetables and risk of colorectal neoplasms: a systematic review and meta-analysis.

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Tse, Genevieve; Eslick, Guy D

2014-01-01

Evidence shows cruciferous vegetables exhibit chemoprotective properties, commonly attributed to their rich source of isothiocyanates. However, epidemiological data examining the association between cruciferous vegetable intake and colorectal neoplasms have been inconclusive. This meta-analysis examines the epidemiological evidence to characterize the association between cruciferous vegetable intake and risk of developing colorectal neoplasms. Thirty-three articles were included in the meta-analysis after a literature search of electronic databases. Subgroup analysis for individual cruciferae types (n = 8 studies) and GST polymorphism (n = 8 studies) were performed. Pooled adjusted odds ratios (ORs) comparing highest and lowest categories of dietary pattern scores were calculated. Results show a statistically significant inverse association between cruciferous vegetable intake and colon cancer [OR = 0.84; 95% confidence interval (CI): 0.72-0.98; P value heterogeneity colorectal (CRC) neoplasms (OR = 0.80; 95% CI: 0.65-0.99; P value heterogeneity = 0.02). Stratification by GST genotype reveals that the GSTT1 null genotype confers a reduction in CRC risk (OR = 0.78; 95% CI: 0.64-0.95; P value heterogeneity = 0.32). This study provides support to the hypothesis that cruciferous vegetable intake protects against cancer of the colon. This study also demonstrates the significance of gene-diet interactions and the importance of assessing individual cruciferous vegetables.

Dietary patterns and depression risk: A meta-analysis.

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Li, Ye; Lv, Mei-Rong; Wei, Yan-Jin; Sun, Ling; Zhang, Ji-Xiang; Zhang, Huai-Guo; Li, Bin

2017-07-01

Although some studies have reported potential associations of dietary patterns with depression risk, a consistent perspective hasn't been estimated to date. Therefore, we conducted this meta-analysis to evaluate the relation between dietary patterns and the risk of depression. A literature research was conducted searching MEDLINE and EMBASE databases up to September 2016. In total, 21 studies from ten countries met the inclusion criteria and were included in the present meta-analysis. A dietary pattern characterized by a high intakes of fruit, vegetables, whole grain, fish, olive oil, low-fat dairy and antioxidants and low intakes of animal foods was apparently associated with a decreased risk of depression. A dietary pattern characterized by a high consumption of red and/or processed meat, refined grains, sweets, high-fat dairy products, butter, potatoes and high-fat gravy, and low intakes of fruits and vegetables is associated with an increased risk of depression. The results of this meta-analysis suggest that healthy pattern may decrease the risk of depression, whereas western-style may increase the risk of depression. However, more randomized controlled trails and cohort studies are urgently required to confirm this findings. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Intra- and Postoperative Complications of Lateral Maxillary Sinus Augmentation in Smokers vs Nonsmokers: A Systematic Review and Meta-Analysis.

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Ghasemi, Samaneh; Fotouhi, Akbar; Moslemi, Neda; Chinipardaz, Zahra; Kolahi, Jafar; Paknejad, Mojgan

This meta-analysis and systematic review focused on the following question: Does tobacco smoking increase the risk of intra- or postoperative complications of lateral maxillary sinus floor elevation? The following electronic databases were searched up to and including November 2015 without language restriction: CENTRAL, MEDLINE, Google Scholar, Scopus, Sirous, and Doaj. Studies were included if rates of intra-or postoperative complications of sinus floor elevation in smokers and nonsmokers were recorded separately. The following complications were assessed: sinus membrane perforation, bleeding, wound dehiscence, wound infection, sinusitis, hematoma, and oroantral fistula. The Critical Appraisal Skills Programme was used to assess the risk of bias in included studies. Random-effects meta-analyses were used to assess the number of each complication in smokers and nonsmokers. Out of 929 eligible publications, 11 articles were included. Meta-analysis of the studies revealed a significantly increased risk of developing wound dehiscence after sinus floor elevation among smokers compared with nonsmokers (Risk Ratio [RR]: 7.82; 95% confidence interval [CI]: 2.38, 25.74; P = .0007). Moreover, risk of developing wound infection was greater in smokers when prospective studies were included in the meta-analysis (RR: 5.33; 95% CI: 1.34, 21.25; P = .02). However, the meta-analysis of included studies did not show significant differences between smokers and nonsmokers concerning risk of sinus membrane perforation and bleeding during sinus floor elevation (P = .46 and P = .33, respectively). Considering the lack of randomized controlled trials and the small number of included studies, the results indicate that smoking seems to be associated with increased risk of wound dehiscence and infection after the sinus augmentation procedure.

Maternal depressive symptoms and early childhood cognitive development: a meta-analysis.

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Liu, Y; Kaaya, S; Chai, J; McCoy, D C; Surkan, P J; Black, M M; Sutter-Dallay, A-L; Verdoux, H; Smith-Fawzi, M C

2017-03-01

Previous findings have been mixed regarding the relationship between maternal depressive symptoms and child cognitive development. The objective of this study was to systematically review relevant literature and to perform a meta-analysis. Three electronic databases (PubMed, EMBASE, PsycINFO) were searched. Initial screening was conducted independently by two reviewers. Studies selected for detailed review were read in full and included based on a set of criteria. Data from selected studies were abstracted onto a standardized form. Meta-analysis using the inverse variance approach and random-effects models was conducted. The univariate analysis of 14 studies revealed that maternal depressive symptoms are related to lower cognitive scores among children aged ⩽56 months (Cohen's d = -0.25, 95% CI -0.39 to -0.12). The synthesis of studies controlling for confounding variables showed that the mean cognitive score for children 6-8 weeks post-partum whose mothers had high depressive symptoms during the first few weeks postpartum was approximately 4.2 units lower on the Mental Developmental Index (MDI) of the Bayley Scales of Infant and Toddler Development (BSID) compared with children with non-symptomatic mothers (B̂ = -4.17, 95% CI -8.01 to -0.32). The results indicated that maternal depressive symptoms are related to lower cognitive scores in early infancy, after adjusting for confounding factors. An integrated approach for supporting child cognitive development may include program efforts that promote maternal mental health in addition to family economic wellbeing, responsive caregiving, and child nutrition.

What can a meta-analysis tell us about traditional birth attendant training and pregnancy outcomes?

Science.gov (United States)

Sibley, Lynn; Ann Sipe, Theresa

2004-03-01

to summarise the available published and unpublished studies on traditional birth attendant (TBA) training effectiveness. a meta-analysis. sixty studies (n=60) spanning 1971-1999 from 24 countries and three regions. the effect size index, Cohen's h for each outcome; the variance-weighted mean effect size and 95% confidence interval for sub-group of outcomes; homogeneity tests on the distribution of the weighted mean effect sizes; and sensitivity analysis to detect the presence of publication bias. TBA training was associated with significant increases in attributes such as TBA 'knowledge' (90%), 'attitude' (74%), 'behaviour' (63%) and 'advice' (90%) over the untrained TBA baseline. Results for 'behaviour' and 'advice' in specific content areas related to peri-neonatal health outcome, however, reveal sources of variability and underscore the conflicting evidence on TBA training. TBA training was also associated with small but significant decreases in peri-neonatal mortality (8%) and birth asphyxia mortality (11%). Incomplete reporting limited the assessment of neonatal mortality due to tetanus and acute respiratory infection, maternal mortality, as well as assessment of the relationship between intervention characteristics and outcomes. The quality of studies included in the meta-analysis lack sufficient rigour to address the question of causality. Thus, while the data suggest that TBA training is effective in terms of the outcomes measured, we are unable to demonstrate that it is a cost-effective intervention. skilled attendance at birth is a distant reality in many developing countries and effective community-based strategies are needed to help reduce high levels of mortality. Given the magnitude of peri-neonatal mortality, the associations observed between TBA training peri-neonatal and birth asphyxia mortality, and TBA attributes in content relevant to peri-neonatal survival, we suggest that these strategies may usefully include TBA training in appropriate

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

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

2017-04-01

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

The pterygoalar bar: A meta-analysis of its prevalence, morphology and morphometry.

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Pękala, Przemysław A; Henry, Brandon Michael; Pękala, Jakub R; Frączek, Paulina A; Taterra, Dominik; Natsis, Konstantinos; Piagkou, Maria; Skrzat, Janusz; Tomaszewska, Iwona M

2017-09-01

The pterygoalar (PA) bar is a bony bridge resulting from the partial or complete ossification of a PA ligament. The aim of this meta-analysis was to systematically analyze and provide the most comprehensive data on the prevalence, morphology and topographical anatomy of the PA bar. A comprehensive search of the major electronic databases (PubMed, Embase, ScienceDirect, SciELO, BIOSIS, and Web of Science) was conducted in order to identify relevant studies. Studies reporting the prevalence, side of occurrence, gender dimorphism and morphometry of the PA bar were included in the current study. A total of 25 articles (n = 16,168 subjects) were included in the meta-analysis. The overall pooled prevalence of the complete PA bar was 4.4% (95% CI: 3.0-6.0) and of the incomplete was 8.4% (95% CI: 4.6-13.3). The PA bar was most often observed unilaterally, on the left side. Analysis of geographical subgroups revealed considerable differences, with the lowest prevalence rates in Europe for both incomplete and complete PA bars. Considering the prevalence and anatomical characteristics of the PA bar, caution is recommended while planning or performing transfacial needle approach to the foramen ovale and when considering a differential diagnosis for nerve compression or entrapment syndromes. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Meta-analysis of self-management education for patients with chronic obstructive pulmonary disease

Directory of Open Access Journals (Sweden)

Hurley J

2012-06-01

Full Text Available BackgroundChronic obstructive pulmonary disease (COPD is a common disease frequently associated with high use of health services. Self-management education is a term applied to programs aimed at teaching patients skills that promote the self-efficacy needed to carry out medical regimens specific to control their disease. In COPD, the value of self-management education is not yet clear and a recent trial was terminated early because of excess mortality in the intervention group.ObjectivesThe objective of this meta-analysis was to assess the settings, methods and efficacy of COPD self-management education programs on patient outcomes and healthcare utilization.Selection criteriaRandomized controlled trials of self-management education in patients with COPD were identified. Studies focusing primarily on comprehensive pulmonary rehabilitation (education and exercise and studies without usual care as a control group were excluded.Search strategyWe searched PubMed (January 1985 to May 2012 as well as other meta-analysis and reviews.Data collection and analysisTwo reviewers (JH and RAR independently assessed study quality and extracted data. Investigators were contacted for additional information.Main resultsThe reviewers included 3 group comparisons drawn from 12 trials. The studies showed no significant change in mortality, with one study being an outlier compared to the others. However, the meta-analysis revealed a reduction in the probability of hospital admission among patients receiving self-management education compared to those receiving usual care.ConclusionsIt is likely that self-management education is associated with a reduction in hospital admissions with no change in mortality. However, because of heterogeneity in interventions, study populations, follow-up time, and outcome measures, data are still insufficient to formulate clear recommendations regarding the preferred curriculum and delivery method of self-management education programs

Obstetric and neonatal outcomes of pregnancies conceived after preimplantation genetic diagnosis: cohort study and meta-analysis.

Science.gov (United States)

Hasson, Joseph; Limoni, Dana; Malcov, Mira; Frumkin, Tsvia; Amir, Hadar; Shavit, Tal; Bay, BjØrn; Many, Ariel; Almog, Benjamin

2017-08-01

Preimplantation genetic diagnosis (PGD) may pose risks to pregnancy outcome owing to the invasiveness of the biopsy procedure. This study compares outcome of singleton and twin clinical pregnancies conceived after fresh embryo transfers of PGD (n = 89) and matched intracytoplasmic sperm injection (ICSI) pregnancies (n = 166). The study was carried out in a single university affiliated centre. Because of the paucity of available data, a literature-based meta-analysis of studies comparing neonatal outcome of PGD and ICSI pregnancies was also conducted. In the retrospective cohort study, obstetric and neonatal outcome were available in 67 PGD and 118 ICSI pregnancies. Perinatal outcomes were comparable between PGD and ICSI pregnancies. Meta-analysis revealed similar outcomes, except for higher rate of low birth weight (<2500 g) neonates in ICSI twin pregnancies (RR 0.86, 95% CI 0.74 to 1.0). Mean birth weight, gestational age at birth, pre-term deliveries (<37 weeks) and malformations were all comparable. In this cohort study and subsequent meta-analysis, no association was found between PGD conceived pregnancies and risks of adverse neonatal or obstetrical outcomes compared with ICSI pregnancies. Hence, blastomere biopsy for PGD does not seem to increase the risk for adverse perinatal outcome compared with ICSI pregnancies. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

How to do Meta-Analysis using HLM software

OpenAIRE

Petscher, Yaacov

2013-01-01

This is a step-by-step presentation of how to run a meta-analysis using HLM software. Because it's a variance known model, it is not run through the GUI, but batch mode. These slides show how to prepare the data and run the analysis.

Financial liberalization and economic growth : A meta-analysis

NARCIS (Netherlands)

Bumann, Silke; Hermes, Niels; Lensink, Robert

This study provides a systematic analysis of the empirical literature on the relationship between financial liberalization and economic growth by conducting a meta-analysis, based on 441 t-statistics reported in 60 empirical studies. We focus on explaining the heterogeneity of results in our sample

4-META opaque resin--a new resin strongly adhesive to nickel-chromium alloy.

Science.gov (United States)

Tanaka, T; Nagata, K; Takeyama, M; Atsuta, M; Nakabayashi, N; Masuhara, E

1981-09-01

1) A new adhesive opaque resin containing a reactive monomer, 4-methacryloxy-ethyl trimellitate anhydride (4-META), was prepared, and its application to thermosetting acrylic resin veneer crowns was studied. 2) The 4-META opaque resin was applied to a variety of nickel-chromium dental alloy specimens which had undergone different treatment, and endurance tests were conducted to evaluate the durability of adhesion. 3) Stable adhesion against water penetration was achieved with metal surfaces first etched with HCl and then oxidized with HNO3. A bond strength of 250 kg/cm2 was maintained even after immersion in water at 37 degrees C for 30 wk or at 80 degrees C for ten wk. Furthermore, this value did not decrease even after the specimens were subjected to 500 thermal cycles. 4) The 4-META opaque resin studied can eliminate the necessity for retention devices on metal castings. 5) The smooth 4-META opaque resin should have no adverse effects on gingivae.

Efficacy of PPV23 in Preventing Pneumococcal Pneumonia in Adults at Increased Risk--A Systematic Review and Meta-Analysis.

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Julia Schiffner-Rohe

Full Text Available Pneumococcal community-acquired pneumonia (pCAP is the most frequent form of pneumonia. The elderly and adults with underlying diseases are at an increased risk of developing pCAP. The 23-valent pneumococcal polysaccharide vaccine (PPV23 was licensed over 30 years ago and is recommended as the standard intervention in many countries across the globe, although its efficacy continues to be debated. We performed a meta-analysis of randomized controlled trials (RCTs to investigate the effect of PPV23 for preventing pCAP in adults ≥60 years of age.An existing Cochrane Review was updated to Oct 2014 using a systematic literature search to select appropriate RCTs. DerSimonian and Laird random-effects meta-analyses were performed and odd ratios (OR with 95%-confidence intervals (CI and p-values were calculated for the descriptive analyses. Reasons for heterogeneity were explored by subgroup analyses.Meta-analysis of PPV23 efficacy included four studies. Three of them did not demonstrate efficacy for PPV23. The body of evidence indicated statistically significant heterogeneity (I2 = 78%, p = 0.004 that could be explained by subgroup analysis by "study setting". Further effect modifiers for pCAP were "continent of trial" (p<0.01, and "method of pneumococcal diagnostics" (p = 0.001. Subgroup analyses revealed that the only study showing efficacy for PPV23 was an outlier. Overall, the validity of the meta-analytic PPV23 efficacy assessment was confirmed by the meta-analysis of all-cause CAP including six studies.Inconsistencies in PPV23 treatment effects to prevent pCAP could solely be explained by one outlier study that was performed in nursing homes in Japan. The effect modifier "method of pneumococcal diagnostics" should be interpreted carefully, since methodological weaknesses are not restricted to one special method only, which would justify the exclusion of certain studies. Overall, we conclude from our meta-analysis that to date there is no proof

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

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Dick J Bierman

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

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

Science.gov (United States)

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

2016-01-01

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

Occurrence of Phlebitis: A Systematic Review and Meta-analysis.

Science.gov (United States)

Chang, Wen P; Peng, Yu X

Peripheral venous catheters (PVCs) are commonly used in clinical practice. However, varying degrees of phlebitis often occur in patients receiving intravenous injections. The relevant literature suggests that phlebitis occurrence is highly associated with the catheter gauge, insertion site, and catheterization duration. Nevertheless, no meta-analysis has been performed on the influence of these three factors on the occurrence of phlebitis. The objective of this study was to determine whether any significant differences exist in the occurrence of phlebitis between catheters of 20 gauge or smaller and those larger than 20 gauge, between catheters inserted in the antecubital fossa and those inserted in other locations on the upper limbs, or between catheters inserted for more than 96 hours and those inserted for 96 hours or less. Using a systematic approach, we searched for literature published between 2006 and 2017 in the Cumulative Index to Nursing and Allied Health Literature (CINAHL), PubMed, ProQuest, and Cochrane Library databases. We used Comprehensive Meta-analysis Version 2 to perform our meta-analysis. After the screening and review processes, we identified 17 studies that met our selection conditions. Among these studies, 14 contained complete data for meta-analysis. These studies involved 4,343 patients and 5,846 PVCs. Regarding the overall effect size in the meta-analysis, the results of the forest plot comparing catheters of 20 gauge or smaller and those larger than 20 gauge presented a risk ratio (RR) of 0.88 (95% confidence interval [0.67, 1.17], p = .380), indicating no statistically significant difference in the occurrence of phlebitis between catheters of the aforementioned gauges. The results of the forest plot comparing catheters inserted in the antecubital fossa and those inserted in other locations on the upper limbs presented an RR of 1.05 (95% confidence interval [0.82, 1.34], p = .696), indicating no statistically significant difference in

Efficacy of metformin in the treatment of NIDDM. Meta-analysis

DEFF Research Database (Denmark)

Johansen, K

1999-01-01

OBJECTIVE: The results differ concerning randomized controlled trials of the effects of metformin on blood glucose regulation and body weight. To get a systematic overview, a meta-analysis of the efficacy of metformin was performed by comparing metformin with placebo and sulfonylurea. RESEARCH...... DESIGN AND METHODS: All randomized controlled trials published since 1957 were selected by searching the Current List of Medical Literature, Cumulated Index Medicus, Medline, and Embase, Meta-analysis was performed calculating weighted mean difference (WMD) of fasting blood glucose, glycosylated...

Effectiveness of Telemedicine for Controlling Asthma Symptoms: A Systematic Review and Meta-analysis.

Science.gov (United States)

Zhao, Jie; Zhai, Yun-Kai; Zhu, Wei-Jun; Sun, Dong-Xu

2015-06-01

The effectiveness of telemedicine for the management of chronic diseases is unclear. This study examined the effectiveness of telemedicine in relieving asthma symptoms. A systematic review of the Medline, Cochrane, EMBASE, and Google Scholar databases was conducted until December 31, 2013 using the following key words: "asthma," "telemedicine," "telehealth," "e-health," "mobile health," "Internet," "telecommunication," "telemanagement," "remote," and "short message service." Inclusion criteria were randomized controlled trial, a diagnosis of asthma, the majority of the patients were ≥18 years of age, and intervention involved any format of telemedicine. A meta-analysis of eligible studies was conducted with the primary outcome being change of asthma symptoms. Of 813 articles identified, 11 were included in the qualitative synthesis, and 6 were included in the meta-analysis. Among the 11 studies, there were 1,460 patients in the intervention groups and 1,349 in the control groups, and the total numbers of participants ranged from 12 to 481 in the intervention groups and from 12 to 487 in the control groups. The mean age of patients ranged in the intervention groups from 34.4 to 54.6 years and in the control groups from 30.7 to 56.4 years. The treatment duration ranged from 0.5 to 12 months. The meta-analysis of six eligible studies revealed no significant difference in asthma symptom score change between the telemedicine and control groups (pooled Hedges's g=0.34, 95% confidence interval=-0.05 to 0.74, Z=1.69, p=0.090). Telemedicine interventions do not appear to improve asthma function scores, but other benefits may be present.

A meta-analysis on diagnostic value of serum cystatin C and creatinine for the evaluation of glomerular filtration function in renal transplant patients.

Science.gov (United States)

Pan, Pan; Binjie, Hu; Min, Li; Lipei, Fan; Yanli, Ni; Junwen, Zhou; Xianghua, Shi

2014-12-01

This meta-analysis aimed to perform a systematic review on comparing the diagnostic value of serum cystatin C and creatinine for glomerular filtration rate in renal transplant patients. The data was extracted into 2×2 table after the articles were assessed by the tool of QUADAS and heterogeneity analysis. The SROC curve and meta-analysis were performed by MetaDisc1.4. Meta-analysis showed that the serum cystatin C had no heterogeneity (P=0.418, I2=2.2%, DOR=25.03), while creatinine heterogeneity was high (P=0.109, I2=37.5%, DOR=9.11). The values of SEN, SPE and SAUC were calculated as 0.86, 0.70 and 0.9015 for cystatin C, and 0.78, 0.73 and 0.8285 for creatinine individually. This study utilized GFR detection and subgroups analysis by cutoff. The PLR was 6.13 and the NLR was 0.12 for cystatin C, compared to SCr (3.72, 0.32). There was homogeneity among these studies using PENIA testing for cystatin C (χ2=2.61, P=0.4560, I2=0.0%. There were significant correlations among cystatin C , creatinine and glomerular filtration rate (GFR). Cystatin C had more sensitivity but less specificity than creatinine for evaluation of GFR. Cystatin C had strong ability in diagnosing renal function after renal transplant and ruling out diagnostic efficacy.

Whole-Body Vibration Exercise for Knee Osteoarthritis: A Systematic Review and Meta-Analysis

Directory of Open Access Journals (Sweden)

Xin Li

2015-01-01

Full Text Available Objectives. To assess the effects of WBV exercise on patients with KOA. Methods. Eight databases including Pubmed, EMBASE, Cochrane Library, CINAHL, Web of Science, the Physiotherapy Evidence Database, CNKI, and Wanfang were searched up to November 2014. Randomized controlled trials (RCTs of WBV for KOA were eligible. The outcomes were pain intensity, functional performances, self-reported status, adverse events, and muscle strength. A meta-analysis was conducted. Results. Five trials with 168 participants provided data for the meta-analysis. No significant difference was shown in pain intensity and self-reported status between WBV and other forms of exercise. Improvement in functional performance (evaluated by BBS; WMD, 2.96; 95% CI, 1.29 to 4.62; P=0.0005 was greater in WBV group, but the other parameters of functional performance (including 6MWT and TGUG revealed no statistically significant difference. Adverse events were only reported in one trial and no significant difference was discovered in muscle strength. The overall quality of evidence was very low. Conclusion. Currently there is only limited evidence that suggested that WBV is effective in the treatment of KOA. Large, well-designed RCTs with better designs are needed.

Meta-analysis reveals association between most common class II haplotype in full-heritage Native Americans and rheumatoid arthritis.

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Williams, R C; Jacobsson, L T; Knowler, W C; del Puente, A; Kostyu, D; McAuley, J E; Bennett, P H; Pettitt, D J

1995-01-01

The association of RA with the alleles at the HLA system was tested among Pima and Tohono O'odham Indians (Pimans) of the Gila River Indian Community of Arizona. Serologic class I (HLA-A, -B, and -C) alleles were typed in 51 individuals with RA and in 302 without RA. Serologic class II (HLA-DR, DQ; DR52 DR53) alleles were typed in a subset of 47 with RA and 147 without RA. Molecular subtypes of DR3X6, DRB1*1402, and *1406 were determined in 29 individuals, 16 with RA and 13 without RA. Among the cases with RA, 46 of 47 had the serologic antigen HLA-DR3X6, as did 140 of 147 of those without the disease. However, this association was not statistically significant because of the high prevalence of the antigen in the controls. Data from Pimans were analyzed with similar results from the Tlingit and Yakima Indians. A meta-analysis employing the Mantel-Haenszel procedure, stratified by tribe, revealed a statistically significant association between the most common haplotype, DRB1*1402 DQA1*0501 DQB1*0301 DRB3*0101, and RA (summary odds ratio = 2.63, 95% confidence interval = 1.08, 6.46). There was also a statistically significant difference in the genotype distributions of one class I locus, HLA-C, between those with and without RA (chi 2 = 12.4, 5 df; p = 0.03). It is concluded that the association with the most common class II haplotype in full-heritage Native Americans might help explain their high prevalence of RA.

An efficient Bayesian meta-analysis approach for studying cross-phenotype genetic associations.

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Arunabha Majumdar

2018-02-01

Full Text Available Simultaneous analysis of genetic associations with multiple phenotypes may reveal shared genetic susceptibility across traits (pleiotropy. For a locus exhibiting overall pleiotropy, it is important to identify which specific traits underlie this association. We propose a Bayesian meta-analysis approach (termed CPBayes that uses summary-level data across multiple phenotypes to simultaneously measure the evidence of aggregate-level pleiotropic association and estimate an optimal subset of traits associated with the risk locus. This method uses a unified Bayesian statistical framework based on a spike and slab prior. CPBayes performs a fully Bayesian analysis by employing the Markov Chain Monte Carlo (MCMC technique Gibbs sampling. It takes into account heterogeneity in the size and direction of the genetic effects across traits. It can be applied to both cohort data and separate studies of multiple traits having overlapping or non-overlapping subjects. Simulations show that CPBayes can produce higher accuracy in the selection of associated traits underlying a pleiotropic signal than the subset-based meta-analysis ASSET. We used CPBayes to undertake a genome-wide pleiotropic association study of 22 traits in the large Kaiser GERA cohort and detected six independent pleiotropic loci associated with at least two phenotypes. This includes a locus at chromosomal region 1q24.2 which exhibits an association simultaneously with the risk of five different diseases: Dermatophytosis, Hemorrhoids, Iron Deficiency, Osteoporosis and Peripheral Vascular Disease. We provide an R-package 'CPBayes' implementing the proposed method.

Meta-analysis of Gaussian individual patient data: Two-stage or not two-stage?

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Morris, Tim P; Fisher, David J; Kenward, Michael G; Carpenter, James R

2018-04-30

Quantitative evidence synthesis through meta-analysis is central to evidence-based medicine. For well-documented reasons, the meta-analysis of individual patient data is held in higher regard than aggregate data. With access to individual patient data, the analysis is not restricted to a "two-stage" approach (combining estimates and standard errors) but can estimate parameters of interest by fitting a single model to all of the data, a so-called "one-stage" analysis. There has been debate about the merits of one- and two-stage analysis. Arguments for one-stage analysis have typically noted that a wider range of models can be fitted and overall estimates may be more precise. The two-stage side has emphasised that the models that can be fitted in two stages are sufficient to answer the relevant questions, with less scope for mistakes because there are fewer modelling choices to be made in the two-stage approach. For Gaussian data, we consider the statistical arguments for flexibility and precision in small-sample settings. Regarding flexibility, several of the models that can be fitted only in one stage may not be of serious interest to most meta-analysis practitioners. Regarding precision, we consider fixed- and random-effects meta-analysis and see that, for a model making certain assumptions, the number of stages used to fit this model is irrelevant; the precision will be approximately equal. Meta-analysts should choose modelling assumptions carefully. Sometimes relevant models can only be fitted in one stage. Otherwise, meta-analysts are free to use whichever procedure is most convenient to fit the identified model. © 2018 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Meta-analysis of gene expression signatures defining the epithelial to mesenchymal transition during cancer progression.

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Christian J Gröger

Full Text Available The epithelial to mesenchymal transition (EMT represents a crucial event during cancer progression and dissemination. EMT is the conversion of carcinoma cells from an epithelial to a mesenchymal phenotype that associates with a higher cell motility as well as enhanced chemoresistance and cancer stemness. Notably, EMT has been increasingly recognized as an early event of metastasis. Numerous gene expression studies (GES have been conducted to obtain transcriptome signatures and marker genes to understand the regulatory mechanisms underlying EMT. Yet, no meta-analysis considering the multitude of GES of EMT has been performed to comprehensively elaborate the core genes in this process. Here we report the meta-analysis of 18 independent and published GES of EMT which focused on different cell types and treatment modalities. Computational analysis revealed clustering of GES according to the type of treatment rather than to cell type. GES of EMT induced via transforming growth factor-β and tumor necrosis factor-α treatment yielded uniformly defined clusters while GES of models with alternative EMT induction clustered in a more complex fashion. In addition, we identified those up- and downregulated genes which were shared between the multitude of GES. This core gene list includes well known EMT markers as well as novel genes so far not described in this process. Furthermore, several genes of the EMT-core gene list significantly correlated with impaired pathological complete response in breast cancer patients. In conclusion, this meta-analysis provides a comprehensive survey of available EMT expression signatures and shows fundamental insights into the mechanisms that are governing carcinoma progression.

Robotic-assisted versus laparoscopic colorectal surgery: a meta-analysis of four randomized controlled trials

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2014-01-01

Background Robotic-assisted laparoscopy is popularly performed for colorectal disease. The objective of this meta-analysis was to compare the safety and efficacy of robotic-assisted colorectal surgery (RCS) and laparoscopic colorectal surgery (LCS) for colorectal disease based on randomized controlled trial studies. Methods Literature searches of electronic databases (Pubmed, Web of Science, and Cochrane Library) were performed to identify randomized controlled trial studies that compared the clinical or oncologic outcomes of RCS and LCS. This meta-analysis was performed using the Review Manager (RevMan) software (version 5.2) that is provided by the Cochrane Collaboration. The data used were mean differences and odds ratios for continuous and dichotomous variables, respectively. Fixed-effects or random-effects models were adopted according to heterogeneity. Results Four randomized controlled trial studies were identified for this meta-analysis. In total, 110 patients underwent RCS, and 116 patients underwent LCS. The results revealed that estimated blood losses (EBLs), conversion rates and times to the recovery of bowel function were significantly reduced following RCS compared with LCS. There were no significant differences in complication rates, lengths of hospital stays, proximal margins, distal margins or harvested lymph nodes between the two techniques. Conclusions RCS is a promising technique and is a safe and effective alternative to LCS for colorectal surgery. The advantages of RCS include reduced EBLs, lower conversion rates and shorter times to the recovery of bowel function. Further studies are required to define the financial effects of RCS and the effects of RCS on long-term oncologic outcomes. PMID:24767102

Individual participant data meta-analysis of prognostic factor studies: state of the art?

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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

Forming Attitudes That Predict Future Behavior: A Meta-Analysis of the Attitude–Behavior Relation

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Glasman, Laura R.; Albarracín, Dolores

2016-01-01

A meta-analysis (k of conditions = 128; N = 4,598) examined the influence of factors present at the time an attitude is formed on the degree to which this attitude guides future behavior. The findings indicated that attitudes correlated with a future behavior more strongly when they were easy to recall (accessible) and stable over time. Because of increased accessibility, attitudes more strongly predicted future behavior when participants had direct experience with the attitude object and reported their attitudes frequently. Because of the resulting attitude stability, the attitude–behavior association was strongest when attitudes were confident, when participants formed their attitude on the basis of behavior-relevant information, and when they received or were induced to think about one- rather than two-sided information about the attitude object. PMID:16910754