382,703 papers found

In the previous article (Network Meta-analysis: Users' Guide for Surgeons-Part I, Credibility), we presented an approach to evaluating the credibility or methodologic rigor of network meta-analyses (NMA), an innovative approach to simultaneously addressing the relative effectiveness of three or more treatment options f…

A database can be used to warehouse quantitative trait loci (QTL) data from multiple sources for comparison, genomic data mining, and meta-analysis. A robust database design involves sound data structure logistics, meaningful data transformations, normalization, and proper user interface designs. This chapter starts wi…

The recent commentary by Derrfuss J, Mar RA. (2009). Lost in localization: the need for a universal coordinate database. Neuroimage, In Press proposed a universal coordinate database to archive functional neuroimaging results. In this response, we discuss our strategy in developing the BrainMap database, which was crea…

Meta-analysis is the quantitative synthesis of information from several studies. It is applicable to a variety of study designs in genetics, from family-based linkage studies and population-based association studies to genome-wide scans and genome-wide association studies. By combining relevant evidence from many studi…

Properly conducted meta-analyses that are based on systematic reviews of the literature allow the conclusive synthesis of accumulating scientific evidence. Systematic reviews, with or without meta-analyses, offer a more objective appraisal of the available evidence compared with traditional narrative reviews. Combining…

The growth of new knowledge continues to advance the surgical disciplines, and several types of literature reviews attempt to consolidate this expansion of information. Meta-analysis is one such method that integrates findings on the same subject from different studies. Within surgery, there is a wealth of literature o…

Publication bias has been previously identified as a threat to the validity of a meta-analysis. Recently, new evidence has documented an additional threat to validity, the selective reporting of trial outcomes within published studies. Several diseases have several possible measures of outcome. Some articles might repo…

Selection and evaluation of evidence to identify the most effective treatment modalities is a difficult process. Randomized controlled trials are well accepted as the least biased means of evaluating medical, surgical, screening or preventive manoeuvres. The most commonly used statistical strategy to pool results from…

I present methods for assessing the relative effectiveness of two treatments when they have not been compared directly in a randomized trial but have each been compared to other treatments. These network meta-analysis techniques allow estimation of both heterogeneity in the effect of any given treatment and inconsisten…

Meta-analysis was developed as a technique for combining the results of many different quantitative studies: it is often used to produce quantitative estimates of causal relations and/or association between variables. Meta-analysis is sometimes regarded as a central component of evidence-based practice. We draw attenti…

Concerning the actual significance level, we investigate the commonly used combined test procedures of meta-analysis, which contain the choice of the model, in which the analysis is carried out, and the commonly used tests for treatment effect in the fixed and random effects model, and some new combined test procedures…

Some methodologists have recently suggested that scientific psychology's over-reliance on null hypothesis significance testing (NHST) impedes the progress of the discipline. In response, a number of defenders have maintained that NHST continues to play a vital role in psychological research. Both sides of the argument…

To-date, most of the meta-analyses performed are exclusively based on published data; however, some are based on individual patient data of published and unpublished trials. This last method is the reference method, but it is time-consuming and costly. The quality of meta-analyses is varied and could partly explain the…

This editorial reports on a meta-analysis done on cholesterol-lowering trials. Coronary heart disease incidence is reported for 16 trials and total mortality for 19 trials. The cholesterol benefit ratio, i.e., the percent risk reduction divided by the percent cholesterol reduction, was analyzed in terms of total vs. po…

Describes the application to community issues of the meta-analytic research strategies increasingly used in many field of psychology. First, we highlight the potential value of meta-analysis to community research. Second, we describe six major steps involved in conducting an effective meta-analysis. These steps include…

A meta-analysis of studies on preparation for medical procedures and pain evaluated the relative effects of sensory; procedural, and combined sensory-procedural preoperational information on coping outcomes. Results indicated that, in contrast to sensory information, procedural information provided no significant benef…

Has the introduction of continuous intrapartum fetal heart rate (F.H.R.) registration resulted in an increase of cesarean section (CS) rates? Our meta-analysis of literature published since 1970 reveals the weak intrinsic value of retrospective studies and the heterogeneity of randomised trials concerning this question…

The Journal of Immigrant and Minority Health recently published a review article by Aran et al. (2023) containing important findings about patterns of suicidality in Newcomers. Although the review provided a valuable contribution to the literature, there was an issue with misclassification of the type of review and ana…

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Periodontal health during orthodontic treatment with clear aligners and fixed appliances: A meta-analysis. Jiang Q, Li J, Mei L, Du J, Levrini L, Abbate GM, Li H. J Am Dent Assoc 2018;149(8):712-20.e12. SOURCE OF FUNDING: The work was supported by grants 81470712 and 8…

Network meta-analysis (NMA) is a statistical technique for making direct and indirect comparisons between different treatment and control groups. Despite its many advantages, NMA may be misleading when evaluating networks that are disconnected, inconsistent or of low reliability and validity. We review how well the ana…