Meta-analyses are statistical methods to evaluate large numbers of clinical trial data sets to answer specific clinical questions. Meta-analyses can be performed when large clinical trials are not available or prior to their availability. It is essential for pharmacists to effectively evaluate potential methodological problems and be aware of the current controversies surrounding meta-analysis. This article will focus on the components of a properly performed meta-analysis and the many sources of bias inherent in a literature review of this magnitude. A suggested reading list of in-depth references concerning the many aspects of meta-analysis is provided for the interested reader.
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