Inverse relationships between socioeconomic status (SES) and mortality and morbidity rates have been documented for almost every disease and condition. People of low SES have financial barriers that impede access to health care, the primary barrier being lack of health insurance. Despite the enactment of Medicaid, income-related health services disparities persist even after accounting for need. Health policy debates over the last several decades have considered initiatives that would guarantee universal coverage to all individuals in the United States in an attempt to ameliorate the persistent inequalities in health and health care. Arguments have been made, however, that access to health care will not be sufficient to substantially reduce the social inequalities in health since countries that have universal health insurance show the same SES-health gradient as found in the United States. The Epidemiology of Health framework, based on the previous works of Blum, Lalonde, Milio, conceptualizes health as a function of four contributing factors: biology, environment, lifestyle, and use of health care services. Guided by this conceptual framework, the proposed study will test the Epidemiology of Health model. Additionally, this study will quantify the determinants of health in a national sample, identify inequities in the determinants of health between the poor and nonpoor, and determine the role of insurance in abating inequities. The proposed study will test the Epidemiology of Health framework using latent variable structural equation modeling with LISREL7 of a cross-sectional, national sample from the 1993 National Health Interview Survey. The conceptual model contains five constructs that have driven the development of a quantifiable empirical model. The empirical model consists of the latent outcome variable, health, whose relationships with predictor variables will be measured by conceptually meaningful and quantitatively derived manifest variables within the dataset.