Joshuan J. Barboza, Escuela de Medicina, Universidad Peruana de Ciencias Aplicadas, Lima, Perú
Emilly Moreno-Ramos, Tau Clinical Research Methods, Trujillo, Perú
Systematic reviews have been established as the most rigorous method for synthesizing scientific evidence in health, provided that two key stages are addressed: the formulation of a clear research question and the design of a robust search strategy. This article presents a narrative review of the methodological literature with the aim of providing a conceptual and practical framework for health science researchers. It examines the structuring of research questions using recognized models such as PICO, PECO, and PEO, which allow for the precise definition of the population, intervention, comparators, and outcomes of interest. In addition, it addresses the process of identifying terms using controlled vocabularies such as MeSH, Emtree, and DeCS, in combination with free terms, which ensures sensitivity and comprehensiveness in searches. Fundamental technical aspects are also analyzed, including the correct use of Boolean operators, the grouping of synonyms, the limitations of truncation, and the risks of using automatic filters without criteria. Finally, recommendations are made for documenting, adapting, and optimizing strategies in different databases, with the aim of promoting more transparent, reproducible, and methodologically sound systematic reviews.
Keywords: Systematic review. Search strategy. PICO. MeSH. Evidence-based medicine. Reproducibility.