Background: Practitioners and decision makers need sufficient information on the external validity of trials in a systematic review to evaluate the applicability and transferability of the results to another population and setting. Objectives: To review the clinical trials of an ongoing Cochrane review in order to determine the extent to which external validity dimensions were reported, develop a conceptual framework to evaluate the applicability and transferability of the evidence to a primary care setting and apply it to the review. Methods: We applied the external validity tool (Green 2006) to evaluate reach and representativeness ; implementation and consistency of effect ; maintenance and institutionalization for the included studies of an ongoing Cochrane review on patient record systems in dental practice and developed a conceptual framework to demonstrate the factors that needs to be considered in evaluating the applicability and transferability of the results to a primary care setting. Results: One trial had a low (53%) participation rate (reach and representativeness) and the actual delivery of the intervention was 62% ( implementation and consistency of effect ). The only demographic factor reported was socioeconomic status. A majority (78%) of participants remained in the study after one year ( maintenance and institutionalization ). The second trial failed to report sufficient information on the recruitment strategy; the actual delivery and follow up was limited with (3% drop out). The conceptual framework helped to identify several factors that need to be considered to evaluate the applicability and transferability of the results of the review to a primary care setting. Conclusion: An external validity tool can help in judging the applicability and transferability of the evidence. The conceptual framework can help systematic reviewers and knowledge users to identify factors that needs to be considered in judging the applicability of evidence to a primary care setting. Green LW, Glasgow RE. Evaluating the relevance, generalization, and applicability of research: issues in external validation and translation methodology. Eval Health Prof. 2006 Mar;29(1): 126 53.