392,240 papers found

In a network meta-analysis, between-study heterogeneity variances are often very imprecisely estimated because data are sparse, so standard errors of treatment differences can be highly unstable. External evidence can provide informative prior distributions for heterogeneity and, hence, improve inferences. We explore a…

Intraclass correlation coefficient (ICC) estimates are necessary for several statistical techniques. Researchers need accurate ICC estimates when conducting prospective power analyses for clustered data scenarios. In addition, meta-analysts require reasonable ICC values when adjusting effect size estimates to account f…

Perlstein, Fair, Hong, and Waller (Journal of Child Psychology and Psychiatry, 2023) meta-analysis provides a critically important summary of the research on the treatment of children and adolescents with elevated callous-unemotional (CU) traits, 10 years after they were added to diagnostic criteria in the "with…

As a complex disease, multiple sclerosis (MS) susceptibility implicates many genetic and environmental factors. Usually, individual genetic association studies have several limitations, and results are specific to the population of study. The Meta-analysis approach has been proposed to resolve these limitations and to…

OBJECTIVES: To perform a worked example of an approach that can be used to identify and remove potentially biased trials from meta-analyses via the analysis of baseline variables. STUDY DESIGN: True randomisation produces treatment groups that differ only by chance; therefore, a meta-analysis of a baseline measurement…

Two new methods for the meta-analysis of factor loadings are introduced and evaluated by Monte Carlo simulations. The direct method pools each factor loading individually, whereas the indirect method synthesizes correlation matrices reproduced from factor loadings. The results of the two simulations demonstrated that t…

A recent meta-analysis by Au et al. Psychonomic Bulletin & Review, 22, 366-377, (2015) reviewed the n-back training paradigm for working memory (WM) and evaluated whether (when aggregating across existing studies) there was evidence that gains obtained for training tasks transferred to gains in fluid intelligence (Gf).…

Meta-analyses today continue to be run using conventional random-effects models that ignore tangible information from studies such as the quality of the studies involved, despite the expectation that results of better quality studies reflect more valid results. Previous research has suggested that quality scores derive…

This article describes the Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) guidelines that are intended to help authors improve the reporting of systematic reviews and meta-analyses, illustrating with examples from the Oncology Nursing Society journals and Putting Evidence Into Practice resou…

The evidence pyramid, originally intended to guide clinicians and students in understanding levels of clinical evidence. Over time, systematic reviews and meta-analyses were elevated to the apex of this hierarchy, often misconstrued as superior to primary research. Systematic reviews and meta-analyses, while powerful i…

In this critical appraisal of a meta-analysis on vitamin D for primary depression, we uncovered several methodological issues, including deviations from stated eligibility criteria, questionable analytical decisions, and the omission of a high-quality clinical trial in the subgroup analyses that supported their main co…

Meta-analytic methods provide a way to synthesize data across treatment evaluation studies. However, these well-accepted methods are infrequent with behavior analytic studies. Multilevel models may be a promising method to meta-analyze single-case data. This technical article provides a primer for how to conduct a mult…

BACKGROUND: Inconsistent reporting in published meta-analyses compared to registered protocol are poorly understood. The aim of the study was to assess inconsistencies between registered protocols and published reports among oncology drug meta-analyses. MATERIALS AND METHODS: A cross-sectional study was performed incl…

OBJECTIVES: It is important to control the quality level of the observational studies in conducting meta-analyses. The Newcastle-Ottawa Scale (NOS) is a representative tool used for this purpose. We investigated the relationship between high-quality (HQ) defined using NOS and the results of subgroup analysis according…

Goodness of fit evaluation should be a natural step in assessing and reporting dose-response meta-analyses from aggregated data of binary outcomes. However, little attention has been given to this topic in the epidemiological literature, and goodness of fit is rarely, if ever, assessed in practice. We briefly review th…

Meta-analysis is a statistical procedure that integrates the results of at least two independent studies. The biggest threats to meta-analysis are publication bias due to missing studies with negative results and low-quality evidence due to methodological limitations imposed by included studies. Tools to improve the qu…

In research aimed at improving human health care, animal studies still play a crucial role, despite political and scientific efforts to reduce preclinical experimentation in laboratory animals. In animal studies, the results and their interpretation are not always straightforward, as no single study is executed perfect…

Population level studies commonly induce the ecological fallacy i.e., the belief that a relationship identified at the population level implies a cause and effect relationship at the level of the individual. A recent research report (DAMASCENE) that related clinical trial effect sizes in cardiovascular cell therapy tri…

This overview examines research synthesis in applied ecology and conservation. Vote counting and pooling unweighted averages are widespread despite the superiority of syntheses based on weighted combination of effects. Such analyses allow exploration of methodological uncertainty in addition to consistency of effects a…