Meta-analysis

Meta‐analysis recognises study‐to‐study variation and looks to see if the data from the different studies are giving a consistent answer. It is used in numerous different ways and both within and outside of the regulatory setting. The technique can provide a quantification of the current state of knowledge regarding a particular treatment both in terms of safety and efficacy. In the applications that are discussed in the chapter, the author focuses on the combination of clinical trials although the methodology can also apply more widely in an epidemiological setting. Each trial that is to be included in the meta‐analysis provides a measure of treatment effect. The chapter presents several methods and reviews them through a case study. In order to ensure that a meta‐analysis is scientifically valid, it is necessary to plan and conduct the analysis in an appropriate and rigorous way.