This is an archived version. For the current version, please go to

Chapter 9:  Analysing data and undertaking meta-analyses 

Editors: Jonathan J Deeks, Julian PT Higgins and Douglas G Altman on behalf of the Cochrane Statistical Methods Group.


Key points


9.1 Introduction

9.2 Types of data and effect measures

9.3 Study designs and identifying the unit of analysis

9.4 Summarizing effects across studies

9.5 Heterogeneity

9.6 Investigating heterogeneity

9.7 Sensitivity analyses

9.8 Chapter information

Box 9.8.a: The Cochrane Statistical Methods Group

9.9 References