How to Write a Critically Appraised Topic (CAT)

Medical knowledge and the volume of scientific articles published have expanded rapidly over the past 50 years. Evidence-based practice (EBP) has developed to help health practitioners get more benefit from the increasing volume of information to solve complex health problems. A format for sharing information in EBP is the critically appraised topic (CAT). A CAT is a standardized summary of research evidence organized around a clinical question, aimed at providing both a critique of the research and a statement of the clinical relevance of results. In this review, we explain the five steps involved in writing a CAT for a clinical purpose (“Ask,” “Search,” “Appraise,” “Apply,” and “Evaluate”) and introduce some of the useful electronic resources available to help in creating CATs.