Systematic Review and Meta-Analysis of Observational Studies in Psychology

The objective of this study was to identify and summarize information on methodologies for conducting systematic reviews and meta-analysis of observational studies, with considerations about their use and relevance in the field of psychology. A systematic review is a literature review based on a research question that uses systematic methods for search, selection and critical appraisal of the included studies, resulting in a summarization. Meta-analysis is a set of statistical techniques to combine and synthesize the results of two or more independent studies, which were included in a systematic review. These methodologies have high relevance in the construction of scientific knowledge, because they synthesize information from studies published in different sources; decrease the delay between scientific discoveries and their applications to professional practice; and allow the testing of new hypotheses from data already collected. The steps to perform a systematic review are described. Specific challenges related to the inclusion of observational studies and the application of this technique to the field of psychology are addressed, in order to guide researchers interested in conducting systematic reviews and meta-analyses, as well as psychologists, other health professionals and managers who seek information on scientific evidence to support their practices.