Inclusion and exclusion strategies for conducting meta-analyses

Abstract

Some of the most important decisions that a researcher will make when conducting a meta-analysis are decisions about the search strategies and inclusion/exclusion criteria. Decisions regarding inclusion/exclusion criteria serve to define the scope of a meta-analysis and search strategy decisions can have a large impact on how well the results of a meta-analysis actually represent the existing body of literature. In this article, we provide descriptions and recommendations for performing searches and making inclusion/exclusion decisions. We also provide a review of 65 meta-analyses of psychotherapy versus pharmacotherapy in order to offer frequency data on the use of various search strategies and inclusion/exclusion decisions in the field.

Keywords: exclusion; inclusion; meta-analysis; psychotherapy research; search strategies; systematic review.