title: Types of clinical studies. Systematic reviews.
abstract: Systematic reviews are analytic instruments that summarize the best available scientific evidence in order to provide evidence-based answers to clinically relevant questions. Meta-analyses are systematic reviews with a quantitative analysis of results. The process of conducting a systematic review is a rigorous and standardized procedure that includes: 1) formulating a clinically relevant question; 2) explicit selection of studies (primary or secondary) to be included in the review; 3) critical appraisal of the relevant evidence; 4) summarizing the evidence; and 5) statistical analysis of the results. In this paper we describe the steps involved in conducting a systematic review of scientific evidence, the methodology, and problems.
authors: Centro de Estudos de Medicina Baseada na Evidência, Faculdade de Medicina de Lisboa, Portugal. avc@fm.ul.pt
authors: Teresa
authors: T
authors: Varandas
authors: António Vaz
authors: AV
authors: Carneiro