Considerations on the use of meta-analyses in the orientation of knowledge and decisions in Occupational Medicine

In recent years, due to the need to elaborate the amount of information available from the scientific literature, the meta-analyses and systematic reviews have become very numerous. The meta-analyses are carried out to evaluate the association between two events when single researches haven't provided comprehensive data. On the other hand, a good meta-analysis must satisfy certain criteria, from the selection of the studies until the evaluation of the outcomes; to this purpose, the application of methods for quality assessment is a crucial point to obtain data of adequate reliability. The aim of this review is to give some introductory tools for a critical approach to meta-analyses and systematic reviews, which have become useful instruments also in occupational medicine.