[Meta-analysis in urological clinical research].

A systematic review is characterized by the application of the scientific method to the evaluation of scientific literature. When a systematic review uses statistical techniques to combine and summarize the results from previous studies, it is called meta-analysis. Meta-analysis is a working tool that facilitates the realization of systematic and quantitative reviews. Its greater objectivity and rigour in comparison with the traditional reviews make that meta-analysis techniques are little by little being generalized as standard instrument to evaluate scientific evidence. In this article we detail the objectives and applications of this type of studies, as well as the stages in its preparation, including the presentation of results.