Methodological aspects of meta-analysis (2)

A meta-analysis is a summary of quantitative synthesis usually used to analyze the results of the primary studies of a systematic review. In order for its conclusions to be valid, its methodology must be correctly applied, paying special attention to carrying out the bibliographical search, combining the studies in an appropriate manner and representing the results correctly. We will review in detail the aspects related to the methods to combine the primary studies and to the interpretation of the forest plot, ending with some recommendations for the interpretation of the results of the meta-analysis.