Meta Analysis

A Primer on Systematic Review and Meta-analysis in Diabetes Research

A systematic review is a rigorous process that involves identifying, selecting, and synthesizing available evidence pertaining to an a priori–defined research question. The resulting evidence base may be summarized qualitatively or through a …

Association between trial registration and treatment effect estimates: a meta-epidemiological study

To increase transparency in research, the International Committee of Medical Journal Editors required, in 2005, prospective registration of clinical trials as a condition to publication. However, many trials remain unregistered or retrospectively …

From pre-registration to publication: A non-technical primer for conducting a meta-analysis to synthesize correlational data

Meta-analysis synthesizes a body of research investigating a common research question. Outcomes from meta-analyses provide a more objective and transparent summary of a research area than traditional narrative reviews. Moreover, they are often used …

Guidelines for Evaluating the Comparability of Down-Sampled GWAS Summary Statistics

Proprietary genetic datasets are valuable for boosting the statistical power of genome-wide association studies (GWASs), but their use can restrict investigators from publicly sharing the resulting summary statistics. Although researchers can resort …

Increasing the transparency of systematic reviews: Presenting a generalized registration form

This paper presents a generalized registration form for systematic reviews that can be used when currently available forms are not adequate. The form is designed to be applicable across disciplines (i.e., psychology, economics, law, physics, or any …

Meta-assessment of bias in science

Numerous biases are believed to affect the scientific literature, but their actual prevalence across disciplines is unknown. To gain a comprehensive picture of the potential imprint of bias in science, we probed for the most commonly postulated …

P values in display items are ubiquitous and almost invariably significant: A survey of top science journals

P values represent a widely used, but pervasively misunderstood and fiercely contested method of scientific inference. Display items, such as figures and tables, often containing the main results, are an important source of P values. We conducted a …

Poor replication validity of biomedical association studies reported by newspapers

Objective To investigate the replication validity of biomedical association studies covered by newspapers. Methods We used a database of 4723 primary studies included in 306 meta-analysis articles. These studies associated a risk factor with a …

Systematic Review of the Empirical Evidence of Study Publication Bias and Outcome Reporting Bias — An Updated Review

Background The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a randomised controlled trial. Study publication bias and outcome reporting …

Systematic Reviews and Meta-Analysis

When used together, systematic review methods and meta-analysis can produce comprehensive, accurate, and useful summaries of empirical evidence to answer questions that are relevant for policy, practice, and future research. Systematic reviews and …