Socioeconomic and need determinants of ambulatory care use: path analysis of the 1970 Health Interview Survey data.

Path analysis is applied to a subsample of the 1970 National Health Interview Survey data to identify the direct and indirect effects of major socioeconomic determinants of ambulatory care utilization. The recursive model of ten equations is predicated on the notion that the dominant determinant is need, measured as activity limitation caused by chronic conditions and restricted activity days. Age, sex, income, education, and other variables are seen both as direct determinants and as acting through their effects on morbidity. The results demonstrate a complex set of relationships among the variables not identifiable in less complex analyses. Both income and education are shown to have pervasive effects. The measure of chronic disability is shown not only to affect utilization directly but to have an even larger indirect effect through its association with increased incidence of acute conditions.