Peter J. Godolphin, Conor Tweed, David J. Fisher
This tutorial describes how to explore across-trial heterogeneity in meta-analysis using trial-level characteristics. It describes how to carry out a subgroup analysis for a trial-level characteristic with more than two categories and provides approaches for analysing continuous trial-level characteristics. The tutorial introduces meta-regression, outlines its intended applications, and explains how to interpret meta-regression results. Common pitfalls when undertaking trial-level subgroup analysis and meta-regression are also discussed. A complementary micro-learning module is provided to support additional learning of these concepts.