Applicability of evidence from randomized controlled trials and systematic reviews to clinical practice: A conceptual review

Abstract

Background: The value of randomized controlled trials is dependent on the applicability of their findings to clinical decision-making. The aim of this study is to determine a definition and principles for the applicability of evidence from randomized controlled trials and systematic reviews. Methods: This narrative review searched studies from PubMed and Web of Science databases using Cochrane Collaboration’s Qualitative Evidence Syntheses guidance. Empirical studies were excluded. Based on the included studies, a definition for the concept and propositions for principles of applicability were formulated. Results: A definition and 11 propositions are presented, 6 propositions having additional sub-propositions. Low risk of bias, ability to answer to specific questions, documentation of the details of how randomized controlled trials turned out, reporting of favourable and adverse outcomes, and systematic comparison of randomized controlled trials and clinical data were considered important. Biomedical randomized controlled trials have the widest applicability, while heterogeneity in study characteristics, human perception, behaviour, environmental, equity factors, and health economic issues lessen applicability. Obtaining applicable evidence is a gradual process. Methodological and substance expertise is necessary for assessing applicability. Discussion: A definition of applicability and requirements for applicable evidence from randomized controlled trials to real-world contexts are presented. Propositions are suggested for any assessment of applicability of findings from randomized controlled trials, systematic reviews and meta-analyses.

Keywords

• applicability
• generalizability
• external validity
• transferability
• randomized controlled trial
• systematic review
• meta-analysis
• benchmarking controlled trial.