Clinician's guide to systematic reviews and meta-analyses.

Systematic reviews answer clinical questions by finding and evaluating all available evidence. The systematic review is a powerful tool to help clinicians use evidence for patient care decisions. There are many sources for high-quality systematic reviews. Like all scientific studies there are potential biases, but systematic reviews have many benefits over narrative reviews. To ensure appropriate use of systematic reviews, clinicians must evaluate them in a logical, step-by-step manner. This article will review the benefits of systematic reviews, how to locate them, and how to evaluate their quality and results.