Systematic reviews and meta-analysis.

BACKGROUND

Systematic reviews and meta-analyses are important research tools in modern medicine. They serve to condense and clarify large amounts of data into resources that can educate clinicians, enhance patient care, help formulate clinical guidelines, and guide future research endeavors.

METHODS

The existing literature, including recently updated guidelines, on systematic reviews and meta-analysis was reviewed and summarized.

RESULTS

A brief background on the origins of systematic reviews is presented, and the advantages and disadvantages of this type of study are discussed. A step-by-step guide to conducting a proper systematic review is outlined, with many illustrative examples. The recently updated reporting guidelines for this type of study are included.

CONCLUSIONS

Using clinical examples and published guidelines, a framework is presented to help the reader properly conduct a systematic review. These guidelines also help the reader conduct a critical appraisal of systematic reviews published in the scientific literature. Even more importantly, principles regarding application of systematic review results to individual patients are addressed.