Exploring Heterogeneity in Meta‐Analysis Using Trial‐Level Characteristics: A Tutorial

ABSTRACT

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.