How do we know when research from one setting can be useful in another? A review of external validity, applicability and transferability frameworks

Objective: To review published frameworks that included criteria for the assessment of external validity, applicability and transferability in their assessment of health research. Methods: Five databases were searched for articles relating to the assessment of external validity or applicability and transferability in health research. A coding framework was developed inductively and used to assess which types of criteria were included in the frameworks. Results: Thirty-eight articles describing 25 frameworks were identified. Eleven focused solely on the assessment of applicability and transferability; 14 presented more general decision-making or evidence appraisal frameworks. The criteria were synthesized into four main categories: setting, intervention, outcomes and evidence. None of the frameworks covered all the criteria identified. A major limitation was the lack of empirical data used to develop many frameworks and the apparent lack of assessment of their perceived utility. Conclusion: A validated framework of applicability and transferability would help those aiming to encourage research use, as well as those conducting research. Greater understanding of applicability and transferability could help to encourage the appropriate use of research and the development of research that is more useful.