Systematic reviews of the literature: the overview and meta-analysis.

Systematic reviews in the form of overviews or meta-analyses offer a solution for busy practitioners who have difficulty keeping abreast of current literature. Because systematic reviews can condense numerous studies into reliable and valid summaries of the best available evidence for a specific clinical problem, they offer significant benefit to busy clinicians. This article has summarized the major features and advantages of systematic reviews. It has distinguished those features that attempt to increase the usefulness of reviews by limiting bias, and it provided a summary of important questions clinicians can use to appraise such reviews critically. With this knowledge, clinicians should be able to use the literature more appropriately and in a timely fashion.