381,816 papers found

The difference between two proportions, referred to as a risk difference, is a useful measure of effect size in studies where the response variable is dichotomous. Confidence interval methods based on a varying coefficient model are proposed for combining and comparing risk differences from multi-study between-subjects…

Meta-analysis uses numerical tools to pool data and to estimate a summary effect size for the comparison of two interventions from a set of randomised controlled trials identified in a systematic review. An effect size is a single number that expresses the difference in outcome from the interventions. The most commonly…

Postoperative radiotherapy remains controversial in non-small cell lung cancer. The conclusions of several meta-analysis are still questioned, partly because of flaws in the randomized trials taken into account. The technological improvements of modern radiotherapy and several clinical observations have led to the laun…

Meta-analysis allows the quantitative combination of results of multiple studies that address similar research questions. Traditional meta-analysis of studies involving a direct comparison of two treatment alternatives can be applied to estimate the overall relative efficacy of these two treatment alternatives. All tre…

Number needed to treat (NNT) is a simple and effective index for clinical therapeutic effect assessment worldwide accepted in recent years. By calculation of absolute risk reduction (ARR) of classified variables, it made the effect estimate reflect objectively the therapeutic effect of an intervention. However, clinica…

Many biomedical applications are concerned with the problem of selecting important predictors from a high-dimensional set of candidates, with the gene expression data as one example. Due to the fact that the sample size in any single study is usually small, it is thus important to combine information from multiple stud…

A systematic review is a transparent and unbiased review of available information. The published systematic review must report the details of the conduct of the review as one might report the details of a primary research project. A meta-analysis is a powerful and rigorous statistical approach to synthesize data from m…

OBJECTIVE: To determine the evidence for efficacy of tonsillectomy in reducing the incidence of recurrent pharyngitis. DATA SOURCES: Literature databases consisting of PUBMED, SCOPUS, CINHAL AND OVID EMBASE including all languages. REVIEW METHODS: Literature search of database by 2 authors with structured criteria us…

In this issue of the, Katz. report on a meta-analysis of school-based interventions (SBIs) for lessening overweight and obesity in children. A hard look at SBIs is certainly warranted and we applaud Katz. for undertaking the task. SBIs have been and remain among the most advocated of anti-obesity approaches and, at lea…

Inguinal hernia repair is one of the most commonly performed general surgical procedures and endoscopic herniorrhaphy has been performed around the world. We review the meta-analysis and recent large randomized controlled trials of endoscopic versus open repairs for inguinal hernia. Currently available evidence shows t…

The evidence-based medicine (EBM) related concepts of hierarchy of evidence, meta-analyses, confidence intervals, study design, etc. are nowadays so widespread, that clinicians willing to use today's medical literature with understanding have no choice but to become familiar with EBM principles and methodologies. Altho…

B. Rind, P. Tromovitch, and R. Bauserman (1998) reported a meta-analysis of the relation between sexual abuse in childhood and adolescence and psychological functioning among college students. Several aspects of their work have proven to be highly controversial, including their assertion that the relation between child…

Meta-analysis is a quantitative method of synthesizing empirical evidence across a collection of related studies and addresses many of the weaknesses of traditional narrative forms of reviewing. This paper describes the basic methods for conducting a state-of-the-art meta-analysis and criticizes 11 extant meta-analyses…

The effectiveness of classroom reality orientation (RO) in dementia was evaluated by conducting a systematic literature review. This yielded 43 studies, of which 6 were randomized controlled trials meeting the inclusion criteria (containing 125 subjects.) Results were subjected to meta-analysis. Effects on cognition an…

Meta-analysis comprises the analysis of the data of similar studies gathered in a systematic review. If the results of the studies differ (strongly), this is called heterogeneity. Possible causes of heterogeneity are: a wrong choice of type of measure of treatment effect, differences of methodological quality between s…

Meta-analysis comprises the analysis of the data gathered in a systematic review. Meta-analysis can be defined as the combination of pooling results of similar studies into one overall estimate of the effect on the one hand and the exploration of sources of heterogeneity between studies on the other. A general statisti…

The computation of effect sizes is a key feature of meta-analysis. In treatment outcome meta-analyses, the standardized mean difference statistic on posttest scores (d) is usually the effect size statistic used. However, when primary studies do not report the statistics needed to compute d, many methods for estimating…

The Confidence Profile Method is a new Bayesian method that can be used to assess technologies where the available evidence involves a variety of experimental designs, types of outcomes, and effect measures; a variety of biases; combinations of biases and nested bases; uncertainty about biases; an underlying variabilit…