Context: Computer-based clinical decision support systems (CDSSs) have been promoted for their potential to improve quality of health care. However, given the limited range of clinical settings in which they have been tested, such systems must be evaluated rigorously before widespread introduction into clinical practice.
Objective: To determine whether presentation of venous thromboembolism prophylaxis guidelines using a CDSS increases the proportion of appropriate clinical practice decisions made.
Design: Time-series study conducted between December 1997 and July 1999.
Setting: Orthopedic surgery department of a teaching hospital in Paris, France.
Participants: A total of 1971 patients who underwent orthopedic surgery.
Intervention: A CDSS designed to provide immediate information pertaining to venous thromboembolism prevention among surgical patients was integrated into daily medical practice during three 10-week intervention periods, alternated with four 10-week control periods, with a 4-week washout between each period.
Main outcome measure: Proportion of appropriate prescriptions ordered for anticoagulation, according to preestablished clinical guidelines, during intervention vs control periods.
Results: Physicians complied with guidelines in 82.8% (95% confidence interval [CI], 77.6%-87.1%) of cases during control periods and in 94.9% (95% CI, 92.5%-96.6%) of cases during intervention periods. During each intervention period, the appropriateness of prescription increased significantly (P<.001). Each time the CDSS was removed, physician practice reverted to that observed before initiation of the intervention. The relative risk of inappropriate practice decisions during control periods vs intervention periods was 3.8 (95% CI, 2.7-5.4).
Conclusions: In our study, implementation of clinical guidelines for venous thromboembolism prophylaxis through a CDSS used routinely in an orthopedic surgery department and integrated into the hospital information system changed physician behavior and improved compliance with guidelines. JAMA. 2000;283:2816-2821