Ankle–brachial index (ABI)
Calculates each leg’s ABI and classifies peripheral arterial occlusive disease (PAOD).
Calculate with transparency
Check the population, units and version. The result shows the formula or classification; it does not make an automatic treatment decision.
Preparing the form…
- Check the method
- Enter the data
- Check the result
Method · Limits of application
AHA 2012: ABI highest ankle SBP/highest brachial SBP; lower ABI between legs
Calculate each leg using the higher ankle systolic pressure on that side and the higher pressure from the two arms; do not use an average of these pressures. Noncompressible arteries, common in diabetes and chronic kidney disease, can falsely elevate the index and require further assessment. A normal resting value does not exclude all ischemia, and the index alone may be insufficient in chronic limb-threatening ischemia. The tool does not replace proper measurement technique, symptoms, vascular examination or complementary tests.
Conditions of use
Check the population, units, inclusion and exclusion criteria, and version in the original source. A result alone does not establish a diagnosis, discharge decision or prescription.
Documented parameters
- Right-arm systolic blood pressure · mmHg
- Left-arm systolic blood pressure · mmHg
- Higher right ankle systolic pressure (posterior tibial or dorsalis pedis) · mmHg
- Higher left ankle systolic pressure (posterior tibial or dorsalis pedis) · mmHg
2/2 reference cases checked. Numerical tests are not clinical validation.
Relationship with cancer research
General context — relationship to be defined
A resource for general clinical contexts. This edition does not assign a specific oncological relationship; selecting it for a study requires a justified question, population and purpose.