The ankle-brachial index (ABI) is currently the most effective, accurate and feasible method for PAD detection. It is quick, easy, noninvasive, and cost-effective. The ABI is obtained by comparing blood pressure in the arm and leg. the German ABI Epidemiological Trial (getABI) showed that the ABI can detect asymptomatic PAD at the same risk as symptomatic peripheral arterial disease (PAD). this epidemiological study was initiated in 2001 to test the accuracy of the ABI and to quantify the risk factors for symptomatic PAD. The study included 6880 non-elective patients, aged 65 years and older, all from 344 primary care clinics in Germany. The study found that an ABI less than or equal to 0.9 (anterior or posterior tibial artery BP/brachial artery BP) identified PAD with 95% sensitivity and 50% specificity, which Diehm said is better than mammography for breast cancer or PSA for prostate cancer. ABI testing was abnormal in 20.8 percent of the overall study population, but most had no clinical signs and symptoms. This asymptomatic PAD had the same risk as symptomatic PAD: there was no significant difference in cardiovascular risk between the two, and PAD itself was a strong independent predictor of death: five-year all-cause mortality for PAD was 24% in symptomatic patients and 19% in patients without symptoms or signs.