Le revisioni della letteratura biomedica

The reviews of the biomedical literature aim to summarize and disseminate the knowledge about a specific topic intended as a disease treatment or a diagnostic biomarker. They include narrative and systematic reviews (SR). Narrative reviews simply describe the features about a specific topic. On the contrary, SR are performed to answer to a specific question by using a standardized methodology to obtain results that may be reproduced by other authors. SR may include studies of diagnostic or therapeutic efficacy and prognostic value according to the scope. SR of treatment efficacy are generally focused on the efficacy of a new treatment in comparison with the one considered as reference, commonly used in the clinical therapeutic protocols. SR focused on diagnostic test accuracy generally retrieve data on diagnostic sensitivity and specificity from original studies in order to estimate pooled likelihood ratios or predictive values. Finally, SR of prognostic studies explore the ability of a specific marker to predict the outcome of interest. A SR implies to plan a systematic literature search strategy by Medline and other biomedical databases, defining inclusion criteria for study selection. Statistical analyses allow to pool data in a meta-analysis to provide an estimates of the effect power. This paper summarize the main features of different type of SR to help readers in the comprension of a SR and meta-analysis. Their utility in clinical practice and biomedical research is also illustrated.