Clinical decision support (CDS) tools designed to digest, filter, organize, and present health data are becoming essential in providing clinical and cost-effective care. Many are not rigorously evaluated for benefit before implementation. We assessed whether computerized CDS for primary care providers would improve atrial fibrillation (AF) management and outcomes as compared to usual care.

Overall, 203 primary care providers were recruited, randomized, and then cluster stratified by location (urban, rural) to usual care (n = 99) or CDS (n = 104). Providers recruited 1,145 adult patients with AF to participate. The intervention was access to an evidenced-based, point-of-care computerized CDS designed to support guideline-based AF management. The primary efficacy outcome was a composite of unplanned cardiovascular hospitalizations and AF-related emergency department visits; the primary safety outcome was major bleeding, both over 1 year. Patients were the units of intention-to-treat analysis.

No significant effects on the primary efficacy (130 control, 118 CDS, hazard ratio: 0.98 [95% CI 0.71-1.37], P = .926) or safety (n = 7 usual care, n = 8 CDS, 1.3% total, P = .939) outcomes were observed at 12-months.

IMPACT-AF rigorously assessed a CDS tool in a highly representative sample of primary care providers and their patients; however, no impact on outcomes was observed. Considering the proliferating use of CDS applications, this study highlights the need for efficacy assessments prior to adoption and clinical implementation.