Approaches to meta-analysis: A guide for LIS researchers

Meta-analysis, a statistical operation used to combine results from independent studies, has been applied widely in medicine, psychology, and business among other disciplines, but has had limited application in LIS research. To introduce it in LIS research, this article offers examples from a meta-analytic study on factors affecting information needs among cancer patients to explain the literature search, criteria for inclusion of studies, data gathering, and statistics related to effect sizes in meta-analysis. Three popular approaches to meta-analysis, the details of the approach used by the author, and the interpretation of results in terms of mean effect sizes that represent strength of the observed effect of variables are also explained.