Assessing the Effects of the Physical,Psychological, and Social Dimensions of Health on the Use of Health Services*

In this paper we examine two major assumptions inherent in the literature relating health status to the use of health services: (1) that each of the three dimensions of health (i.e., the physical, the psychological, and the social) has an equal impact on the use of health services; and (2) that the effects of these three dimensions of health are manifest in an additive rather than in an interactive fashion. To test these assumptions, multiple regression analyses are performed using a modified version of the generic model of access to medical care in order to predict eight different types of health services utilization. The results compel us to accept the additivity assumption, while rejecting the equality assumption. Moreover, contrary to Mechanic's assertion, psychological health was found to have the least impact of any of the three dimensions of health on the use of health services. We then discuss two possible explanations (i.e., differences in the populations studied and the measurement of the independent variables) that might account for the disparity between Mechanic's and our own findings. Although further study is needed before any firm conclusions may be drawn, the evidence suggests that Mechanic's findings may be specific to the HMO populations that he sampled.