DESCRIPTION: Phase II completes development of the Apnea Risk Evaluation System (ARES), an integrated method, including: a) a physiological data acquisition device, easily self-applied to the forehead and comfortably worn throughout the night to collect data to screen for SA (Sp02, pulse, snoring and head position), b) software to identify respiratory events and distinguish movement artifacts, c) a questionnaire with Profile Analysis to assess SA risk factors, and d) expert system logic to quantify level of risk for SA. ARES will be compared directly to overnight polysomnography (PSG) on 400 patients referred to a sleep clinic, 50 patients diagnosed with hypertension, diabetes and depression with symptoms similar to SA and 10 healthy subjects. ARES Questionnaires from 100 healthy subjects will be acquired to cross-validate the Profile Analysis with PSG to verify subjects classified Profile Analysis "at-risk" for SA. Since AIRES is designed to be easily self-applied and worn at home, 20 healthy subjects and 50 SA patients will complete the questionnaire and wear the ARES Device at home, following instructions for self application. In home data will be compared to in lab PSG and ARES. Clarity of instructions, ease of application and comfort of the device when worn at home will also be evaluated. PROPOSED COMMERCIAL APPLICATION: Sleep Apnea is a serious, prevalent, under-diagnosed, but treatable disorder, creating a significant market demand for accurate, inexpensive and easy-to-administer assessment methods. The ARES willbe marketed to Managed care providers, HMOs and other medical professionals, including those involved with Occupational and Industrial Medicine and epidemiology. The ARES will also be marketed directly-to-consumers as an in-home risk assessment for SA.