A re‐evaluation of fixed effect(s) meta‐analysis. (16th March 2017)

• Record Type: Journal Article
• Authors: Rice, Kenneth; Higgins, Julian P. T.; Lumley, Thomas
• Is Part Of: Journal of the Royal Statistical Society. Volume 181:Number 1(2018)
• Page Start: 205
• Page End: 227
• Publication Date: 2017-03-16
• Subjects: Common effect -- Fixed effect -- Fixed effects -- Meta‐analysis -- Meta‐regression -- Random effect; Social sciences -- Statistical methods -- Periodicals; Statistics -- Periodicals; 300.15195
• DOI: 10.1111/rssa.12275
• Languages: English
• ISSNs: 0964-1998

Abstract

Summary: Meta‐analysis is a common tool for synthesizing results of multiple studies. Among methods for performing meta‐analysis, the approach known as 'fixed effects' or 'inverse variance weighting' is popular and widely used. A common interpretation of this method is that it assumes that the underlying effects in contributing studies are identical, and for this reason it is sometimes dismissed by practitioners. However, other interpretations of fixed effects analyses do not make this assumption, yet appear to be little known in the literature. We review these alternative interpretations, describing both their strengths and their limitations. We also describe how heterogeneity of the underlying effects can be addressed, with the same minimal assumptions, through either testing or meta‐regression. Recommendations for the practice of meta‐analysis are given; it is hoped that these will foster more direct connection of the questions that meta‐analysts wish to answer with the statistical methods they choose.