Measurement of ankle blood pressures in a seated position will grossly overestimate the ABI (by approximately 0.3).

[citation needed] The higher systolic reading of the left and right arm brachial artery is generally used in the assessment.

Studies have shown the sensitivity of ABPI is 90% with a corresponding 98% specificity for detecting hemodynamically significant (stenosis of more than 50%) in major leg arteries, defined by angiogram.

[3] However, ABPI has known issues: When performed in an accredited diagnostic laboratory, the ABI is a fast, accurate, and painless exam, however these issues have rendered ABI unpopular in primary care offices and symptomatic patients are often referred to specialty clinics[13] due to the perceived difficulties.

[14] An ABPI value of 1.3 or greater is also considered abnormal, and suggests calcification of the walls of the arteries and incompressible vessels, reflecting severe peripheral vascular disease.