Income, social stratification, class, and private health insurance: a study of the Baltimore metropolitan area.

Most studies of inequalities and access to health care have used income as the sole indicator of social stratification. Despite the significance of social theory in health insurance research, there are no empirical studies comparing the ability of different models of social stratification to predict health insurance coverage. The aim of this study is to provide a comparative analysis using a variety of theory-driven indicators of social stratification and assess the relative strength of the association between these indicators and private health insurance. Data were collected in a 1993 telephone interview of a random digit dialing sample of the white population in the Baltimore Metropolitan Statistical Area. Indicators of social stratification included employment status, full-time work, education, occupation, industry, household income, firm size, and three types of assets: ownership, organizational, and skill/credential. The association between social stratification and private health insurance was strongest for those having higher household incomes, having attained at least a bachelor's degree, and working in a firm with more than 50 employees, followed by being an owner or manager, and by being employed. The addition of education and firm size improved the prediction of the household income model. The authors conclude that studies of inequalities in health insurance coverage can benefit from the inclusion of theory-driven indicators of social stratification such as human capital, labor market segmentation, and control over productive assets.