382,703 papers found

The random-effects model allows for the possibility that studies in a meta-analysis have heterogeneous effects. That is, observed study estimates vary not only due to random sampling error but also due to inherent differences in the way studies have been designed and conducted. In this chapter, we consider methods…

Hunasikatti M. Effect of treatment of central sleep apnea/Cheyne-Stokes respiration on left ventricular ejection fraction in heart failure: a network meta-analysis is not the answer.. 2020;16(4):651–652.

The volume of medical literature is growing at a rate that renders decision-making difficult without specialized summary tools. Systematic reviews and meta-analyses are important research instruments used to condense and clarify a broad scope of information into manageable summaries. When used effectively, these report…

A primary goal of meta-analysis is to improve the estimation of treatment effects by pooling results of similar studies. This article explains how the most widely used method for pooling heterogeneous studies--the Der Simonian-Laird (DL) estimator--can produce biased estimates with falsely high precision. A classic exa…

The author discusses the significance and potential pitfalls in performing a meta-analysis underscoring the importance of a usual forgotten issue in meta-analysis called clinical heterogeneity. Clinical heterogeneity can mislead results and misinform clinicians. Practical examples from the literature are given, and the…

Meta-analysis is often conducted with only a small number of studies. Adjustments of the (restricted) maximum likelihood estimator of the effect size are derived and their gains in efficiency are explored. The proposed estimators are applied to three sets of studies.

The purpose of meta-interpretive literature reviews is to combine the individual findings of different studies into a single, coherent analysis (here: meta-studies). The positions on how to handle that differ enormously. This is reflected in the variety of terms and definitions for synonym circumstances, e.g. "meta-ana…

Meta-analysis, the statistical combination of results from several studies to produce a single estimate of a treatment effect or size of an association, continues to attract controversy. We illustrate and discuss the promises and limitations of meta-analysis. Meta-analysis of clinical trials can prevent delays in the i…

This review covers the basic principles of systematic reviews and meta-analyses. The problems associated with traditional narrative reviews are discussed, as is the role of systematic reviews in limiting bias associated with the assembly, critical appraisal, and synthesis of studies addressing specific clinical questio…

The overall goal of a systematic review or meta-analysis is to combine results of previous studies to arrive at summary conclusions about a body of research. In radiology, systematic reviews or meta-analyses can be used to calculate a summary estimate of effect size of a treatment that used imaging data to assess outco…

When performing a meta analysis, it is often necessary to combine results from several 2 x 2 contingency tables. The Mantel-Haenszel model assumes a common measure of association between the treatment and outcome variables across the tables. A Bayesian method is described for drawing inferences regarding the measure of…

In this paper, we describe an exact method for estimating a common relative risk across different epidemiologic study designs. The types of studies allowed by the method include case-control studies, follow-up studies with an internal comparison group, and follow-up studies with an external comparison group. Because th…

We propose the adaptation of classical monitoring boundaries for use in cumulative meta-analysis as guidelines for deciding when accumulating evidence is statistically significant and medically convincing. The interpretation of information from a randomized controlled trial is compared with that from a meta-analysis. T…

Synthesis of research findings has long been a part of reviewing and summarizing a field of study. Public health decisions are made on the available evidence. We summarize the approaches to research synthesis that draw on the best available evidence and the use of quantitative summaries through meta-analysis. We focus…

Meta-analysis seems to have a potentially useful role in carefully selected situations where the primary literature is of good quality, heterogeneity in the response to treatment of the tested population is small and well-understood, interest centers on estimation of a specific, critical parameter of outcome, and the m…