The Medical Outcomes Study (SF-20) instrument,
which has been validated and found to be
reliable in large populations of healthy and diseased
individuals, was used to measure physical, social, and
role functioning, well-being, and overall health.
Each of the five domains measured was scored separately on a scale of 0% to 100%. A typical range
of responses for many diseases, although not PAD,
has been established for this questionnaire