Multidimensionality of health status in an elderly population. Construct validity of a measurement battery.

Although health is generally accepted to be a multidimensional construct, the relationship among various domains has not been well defined. To understand this issue better we used principal components analysis to examine the relations among a set of health status measures gathered on 590 elderly members of a health maintenance organization (HMO). These included functional health, emotional health, social activity within and outside of the family, and cognitive functioning (all based on patient interview), physicians' ratings of patients' health, and chart-derived data on physiologic health. Support was obtained for the umbrella concept of "health" as well as for six subcomponents: functional health, emotional health, physiologic health, both kinds of social activity, and cognitive functioning. Patients' ratings of their overall physical and mental health were related to functional, physiologic, and emotional health factors, whereas physicians' ratings of overall physical and mental health were never related to the emotional health factor. This suggests that patients may hold a broader frame of reference in gauging overall health than physicians do.