Meta-analysis. What have we learned?


      Meta-analyses constitute fundamental tools of the Evidence-Based Medicine (EBM) aiming at synthesizing outcome data from individual trials in order to produce pooled effect estimates for various outcomes of interest. Combining summary data from several studies increases the sample size, improves the statistical power of the findings as well as the precision of the obtained effect estimates. For all these reasons, meta-analyses are thought of providing the best evidence to support clinical practice guidelines. However, the strength of the provided evidence is closely dependent on the quality of included studies as well as the rigour of the meta-analytic process. In addition, over the course of the evolution of the current meta-analytic methodology, some concerns have been expressed on the ultimate usefulness of such a complex and time consuming procedure on establishing timely, valid evidence on various specified topics in the field of Orthopaedics and Trauma Surgery. This article provides an overview of the appropriate methodology, benefits and potential drawbacks of the meta-analytic procedure.


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