Meta-analysis

Abstract

Meta-analysis is a statistical tool for combining the results of different studies on the same topic, providing a precise estimate of the effect size and increasing statistical strength, which is particularly important when the strength of the primary study is limited because of a small sample size. Properly conducted meta-analysis provides an invaluable link between past and future studies by quantitatively synthesizing evidence while minimizing bias. Recently, because studies on meta-analysis have been published increasingly, there is a need for rheumatologists to understand meta-analysis. In order to help rheumatologists in use of a meta-analysis, the author describes the basic steps in statistical analysis of a meta-analysis: 1) search for presence of between-study heterogeneity, 2) performing statistical analysis of meta-analysis, 3) checking publication bias, 4) search for causes of heterogeneity, and 5) interpreting and presenting meta-analysis results. (J Rheum Dis 2015;22:4-9)