Summarizing research findings: systematic review and meta-analysis.

The explosion of biomedical publishing makes keeping up with the primary studies an impossible task. The often disparate, confusing and contradicting findings of individual studies makes healthcare professionals turn to review articles where knowledge has been collated and published in summaries. Narrative reviews lack rigorous, systematic and reproducible synthesis. In contrast, systematic reviews are conducted using systematic and explicit methods to identify, select and critically appraise relevant research, and to collect and analyse data from the studies that are included in the review. The final pathway for systematic review is a statistical summary of the results of primary studies, or meta-analysis. This article provides some guidelines to health care providers in understanding the key aspects of systematic review and meta-analysis. Steps involved in systematic review are discussed. The potential pitfall of meta-analysis was also explored.