392,145 papers found

Meta-analysis of individual patient data (IPD) is the gold-standard for synthesizing evidence across clinical studies. However, for some studies IPD may not be available and only aggregate data (AD), such as a treatment effect estimate and its standard error, may be obtained. In this situation, methods for combining IP…

Meta-analyses can be powerful tools to combine the results of randomized clinical trials and observational studies to make consensus inferences about a medical issue. It will be demonstrated that a common practice of testing for homogeneity of effect size, and acting upon the inference to decide between fixed vs random…

OBJECTIVE: To critically assess the quality of literature about systematic review or meta-analysis on traditional Chinese medicine (TCM) published in Chinese journals. METHODS: Electronic searches in CNKI, VIP and Wanfang data-base were conducted to retrieve the systematic reviews or meta-analysis reports on TCM, incl…

Previous reviews and meta-analyses that addressed abnormal Stroop interference in attention-deficit/hyperactivity disorder (ADHD) yielded mixed results. The authors of the present study argue that the inconsistencies may reflect the problematic nature of 2 frequently used methods to quantify Stroop interference-the dif…

The aim of the present study was to examine impairment of implicit learning in Parkinson's disease (PD) by means of a meta-analysis of studies that used the serial reaction time (SRT) task. The authors performed a systematic review and meta-analysis of published journal articles (1987-2005) that used the SRT task with…

Often multiple outcomes are of interest in each study identified by a systematic review, and in this situation a separate univariate meta-analysis is usually applied to synthesize the evidence for each outcome independently; an alternative approach is a single multivariate meta-analysis model that utilizes any correlat…

A number of studies have tested the association of the complement receptor 1 (CR1) and Interleukin-10 (IL10) polymorphisms with systemic lupus erythematosus (SLE), but reported conflicting results. The aim of the study is to explore whether the CR1 and IL10 genes are associated with SLE susceptibility. We surveyed stud…

Genome searches for identifying susceptibility loci for the same complex disease often give inconclusive or inconsistent results. Genome Search Meta-analysis (GSMA) is an established non-parametric method to identify genetic regions that rank high on average in terms of linkage statistics (e.g., lod scores) across stud…

A common problem that arises in the meta-analysis of several studies, each with independent treatment and control groups, is to test for the homogeneity of effect sizes without the assumptions of equal variances of the treatment and the control groups and of equal variances among the separate studies. A commonly used t…

OBJECTIVE: Current methods for meta-analysis of diagnostic tests do not allow utilizing all the information from papers in which several tests have been studied on the same patient sample. We demonstrate how to combine several studies of diagnostic tests, where each study reports on more than one test and some tests (b…

OBJECTIVES: To describe past practice in meta-analyses found in occupational epidemiology, identifying the major issues that should be considered by researchers planning a meta-analysis in this setting. METHODS: An electronic search of relevant online databases was undertaken. Papers were included in the review if the…

Heterogeneity can be a major component of meta-analyses and by virtue of that fact warrants investigation. Classic analysis methods, such as meta-regression, are used to explore the sources of heterogeneity. However, it may be difficult to apply such a method in complex cases or in the absence of an a priori hypothesis…

The extent of heterogeneity in a meta-analysis partly determines the difficulty in drawing overall conclusions. This extent may be measured by estimating a between-study variance, but interpretation is then specific to a particular treatment effect metric. A test for the existence of heterogeneity exists, but depends o…

Thirty-five articles and a number of abstracts have been published in the medical literature looking at the relationship between male circumcision and HIV infection. Study designs have included geographical analysis, studies of high-risk patients, partner studies and random population surveys. Most of the studies have…

The Authors have developed a work of meta-analysis on the employment of IFN in the virus-correlated chronic hepatitis. They have examined World literature on: virus causing chronic hepatitis, type and duration of the treatment, criteria in the choice of the observed patients, clinical effects, effects on the virus, eff…

When little or no data directly comparing two treatments are available, investigators often rely on indirect comparisons from studies testing the treatments against a control or placebo. One approach to indirect comparison is to pool findings from the active treatment arms of the original controlled trials. This approa…

Cross-section regression analyses of some of the world's populations suggest a direct linear relationship between mean blood pressure and mean salt-intake. Since such investigations have hitherto been partly based on information about dietary salt intake, which is a questionable measure, we performed an analysis includ…

There is a lack of consensus among studies on the possible risks of stroke from cigarette smoking; because of this a meta-analysis was conducted. All published data on the association were sought and the relative risk for each study obtained whenever possible. The pooled relative risks were calculated by using estimate…

BACKGROUND: Liver resection creates a clinical tension between limiting operative bleeding and maintaining organ perfusion. Low central venous pressure, fluid restriction, vascular inflow occlusion and vasoactive treatment can coincide with lower arterial pressure, yet existing reviews have centred on blood loss and tr…

The aim of this study was a quantitative review of the published results concerning the treatment effects of maxillary protraction in patients with Angle Class III using the meta-analysis method. 85 articles published between 1966 and 1998 were reviewed under strict, pre-defined criteria. Of these, 12 studies presentin…