All 624 subjects were initially studied under a Lipid Research Clinic protocol that involved two evaluations, visit 1 and visit 2. At visit 2, half of the subjects were from a random sample of the LRC visit 1 cohort and others were selected from the visit 1 cohort for hyperlipidemia, defined as being at or above age- and sex-specific 90th percentiles for cholesterol or 95th percentiles for triglycerides or taking lipid-lowering medications. At visit 2, the subjects were characterized as to age; sex; drug, diet, alcohol and smoking history; personal and family history of cardiovascular disease; Rose questionnaire; and electrocardiogram and examination by a cardiologist. The subjects were given a traditional manual examination for peripheral arterial disease and four non-invasive tests including segmental blood pressure, flow velocity by Doppler ultrasound, postocclusive reactive hyperemia, and pulse reappearance half-time. The subjects were categorized into large vessel peripheral arterial disease, isolated small vessel peripheral arterial disease or normal based on the results of non-invasive testing and followed for an average of four years.