Predicting mortality from community surveys of older adults: the importance of self-rated functional ability.

Using data from the 1990 baseline of the National Survey of Self-Care and Aging (NSSCA), and nearly three years of follow-up mortality data, we examined the association between self-rated functional ability, a global measure of perceived ability of function independently, and mortality among a national sample of older adults. The study included 3,485 subjects selected from the Medicare Beneficiary Files according to a stratified random sampling design, with approximately equal numbers of adults by gender in each of three age categories, 65-74, 75-84, and 85 and over. Self-rated functional ability was found to have an independent contribution to the subsequent risk of death among older adults. Using multivariate models that accounted for self-rated health, age, gender, medical conditions, functional status, and assistance from others, poor self-ratings on this single item nearly doubled the risk of death during the follow-up period. These findings suggest the importance, for both researchers and clinicians, of measuring the potential prognostic importance of self-ratings of health and self-ratings of functional ability among older adults.