382,714 papers found

Meta-analysis is widely used to combine the findings of multiple disparate studies of health risks or treatment response. Meta-analysis often uses a random-effects model to express heterogeneity across studies. The model interprets a weighted average of study-specific estimates as an estimate of a mean parameter across…

The Enhancing Neuroimaging Genetics through Meta-analysis (ENIGMA) Consortium is a global team science effort, now including over 800 scientists spread across 340 institutions in 35 countries, with the shared goal of understanding disease and genetic influences on the brain. This "crowdsourcing" approach to team neuros…

In systematic reviews based on network meta-analysis, the network structure should be visualized. Network plots often have been drawn by hand using generic graphical software. A typical way of drawing networks, also implemented in statistical software for network meta-analysis, is a circular representation, often with…

Studies of epidemiological and prognostic factors are very important for oncology practice. There is a rapidly increasing amount of research and resultant knowledge in the scientific literature. This means that health professionals have major challenges in accessing relevant information and they increasingly require be…

A study-level meta-analysis has shown that proton magnetic resonance spectroscopy is a promising prognostic marker in neonatal hypoxic-ischemic encephalopathy. An individual patient data meta-analysis could yield a prognostic tool with improved accuracy enabling well-founded clinical decisions. Our request to share pat…

Meta-analyses in clinical research usually aimed to evaluate treatment efficacy and safety in direct comparison with a unique comparator. Indirect comparisons, using the Bucher's method, can summarize primary data when information from direct comparisons is limited or nonexistent. Mixed comparisons allow combining esti…

In a meta-analysis results of different studies are summarized quantitatively. This gives a much more precise effect estimate than is possible in individual studies. Prior to the analysis, all relevant studies should be traced, including studies with less favourable results. Exclusion of 'negative' studies may lead to…

Meta-analyses can be an excellent method to summarize the existing literature of studies concerning orthopaedic implants and devices. It is important to understand how meta-analyses are conducted and to be able to evaluate whether a meta-analysis has strong methodological rigor to help with clinical decisions. This pap…

Ideally, clinical decision making ought to be based on the latest evidence available. However, to keep abreast with the continuously increasing number of publications in health research, a primary health care professional would need to read an insurmountable number of articles every day covered in more than 13 million…

Methods for the meta-analysis of results from randomized controlled trials are well established. However, there are currently no methods for the meta-analysis of method comparison studies. Here the combination of results from studies comparing two methods of measurement on the same unit of observation is required. We c…

For the meta-analysis of controlled clinical trials with binary outcome a test statistic for testing an overall treatment effect is proposed, which is based on a refined estimator for the variance of the treatment effect estimator usually used in the random-effects model of meta-analysis. In simulation studies it is sh…

The technique of meta-analysis provides a systematic and quantitative approach to the summary of results from a collection of similar randomized studies. Comprehensive methodology exists for analysis when all trials are of a fixed sample size design, but this is based on assumptions which are no longer valid when incor…

For a meta-analysis to give definitive information, it should meet at least the minimum standards that would be expected of a well-designed, adequately powered, and carefully conducted randomised controlled trial. These minimum standards include both qualitative characteristics--a prospective protocol, comparable defin…

The problem of drug interchangeability among a brand-name drug and its generic copies is considered. Under current Food and Drug Administration (FDA) regulation, a patient may switch from the brand-name drug to a generic drug if the generic drug is shown to be bioequivalent to the brand-name drug based on bioequivalenc…

Meta-analysis is a popular statistical tool allowing the synthesis of related research studies in a quantitative manner. Components of a good meta-analysis are first discussed, with a view toward critical reading of reports of meta-analyses. Examples include lipid-lowering drugs and coronary artery bypass graft surgery…

Meta-analysis of clinical trials has assumed increasing importance in recent years as a means of reaching conclusions regarding the safety and efficacy of treatments evaluated in individual trials. This article discusses impediments to meta-analyses and enumerates needs that should be satisfied to enhance their usefuln…

Forty-eight experimental studies of nonmechanically assisted relaxation techniques used to control a variety of clinical symptoms were synthesized using meta-analysis. Effect sizes for three types of comparisons, experimental-control, experimental-placebo, and pre-post, ranged from .43 to .66, demonstrating that treatm…

Attitudes toward the elderly have been examined in a number of empirical studies, yet the question of whether the elderly are viewed more negatively than younger persons has not been resolved. A meta-analysis of the literature was conducted to examine this question; results demonstrated that attitudes toward the elderl…

Network meta-analysis (NMA), also known as mixed treatment comparison meta-analysis or multiple treatments meta-analysis, extends conventional pairwise meta-analysis by simultaneously synthesizing multiple interventions in a single integrated analysis. Despite the growing popularity of NMA within comparative effectiven…