Measurement of functional ability in patients with coronary artery disease

The purpose of this study was to examine measures of functional ability in a group (n = 60) of cardiac patients undergoing treadmill exercise tests. Functional ability was defined as the degree to which the individual is able to perform physical activity in the absence of symptoms. Instruments used were the Modified Harvard Alumni Scale (MHAS), the Symptom Scale (SS) comprised of the following subscales: angina (AS), shortness of breath (SOBS), and fatigue (FS); the overall Health Rating Index (OHRI); and the Goldman Specific Activity Scale (SAS). Concurrent validity was supported by the fact that the instruments were correlated with metabolic equivalents achieved on the treadmill. Correlations were: MHAS (r = .34, P < .01), SS (r = .67, p < .01), AS (r = .54, p < .01), SOBS (r = -.41, p < .05), FS (r = -.56, P < .001) and the OHRI (r = .45, p < .001). Reliability was determined using Cronbachs, alpha and were: SS = .92, AS = .87, SOBS = .86, FS = .85 and OHRI = .88. Findings support the need for testing and evaluation of instruments measuring functional ability in diverse cardiovascular populations.