Derivation and validation of REASON: A risk score identifying candidates to screen for peripheral arterial disease using ankle brachial index

Abstract Background The recommendation of screening with ankle brachial index (ABI) in asymptomatic individuals is controversial. The aims of the present study were to develop and validate a pre-screening test to select candidates for ABI measurement in the Spanish population 50–79 years old, and to compare its predictive capacity to current Inter-Society Consensus (ISC) screening criteria. Methods and results Two population-based cross-sectional studies were used to develop ( n =4046) and validate ( n =3285) a regression model to predict ABI The best model to predict ABI χ 2 : 10.73 (df=6), p -value=0.097). Predictions (probability cut-off value of 4.1) presented better specificity and positive likelihood ratio than the ABI screening criteria of the ISC guidelines, and similar sensitivity. This resulted in fewer patients screened per diagnosis of ABI Conclusion This model provides accurate ABI