[Clinical decision-making: systematic reviews and meta-analysis]

Abstract

Randomized clinical trials and mainly meta-analysis, have become the gold standard in the assessment of drug efficacy. A meta-analysis is a systematic review that uses statistical techniques to combine and summarize results of previous studies. Thereby, their design helps to identify and explain inconsistencies in the results of previous studies. One of the most complex and valid designs consists in obtaining the original database for each study (published or not) performing a <<pooled analysis>> or meta-analysis of individualized patient data. This type of meta-analysis avoids the partiality which may originate from the non-publication of nonsignificant studies. The future tendency would recommend that investigators, clinicians, reviewers, journal editors and sponsors agree on publication criteria other than positive p values such as clinical validity and clinical relevance.