Relationship of domain-specific measures of health to perceived overall health among older subjects.

The associations between nine domain-specific measures of health (e.g., depressive symptoms, psychological distress, mental health, physical functioning, role functioning, social functioning, bodily pain, somatic symptoms, and chronic medical morbidity) and a single-item measure for perceived overall health were studied in an extensive community-based sample of elderly persons (n = 5279). The results showed that: (1) the discriminative power of perceived overall health compared to domain-specific measures of health was moderate to large only at the fair/poor end of the perceived overall health spectrum; (2) a single-item measure of perceived overall health did not cover domain-specific measurements of health since only 41.8% of the variance in perceived overall health was explained by all domain-specific measures; and (3) the affective domains of functioning (psychological distress, mental health) were weakly related to perceived overall health. Bodily pain, chronic medical morbidity and, to a lesser extent, physical functioning were more strongly related to perceived overall health. These results were fairly consistent for men and women and for three age groups. We conclude that a global, single-item measure of perceived health and domain-specific health measures are not exchangeable in evaluation, survey, or epidemiological research.