Sources of ambulatory care and utilization models.

For this study I gathered information on sources of ambulatory care and ambulatory care utilization, together with social, demographic, and health information. I applied a revision of Andersen's behavioral utilization model to all these data to try to explain patterns of ambulatory care utilization. Data are from a household survey of Rhode Island residents that was conducted in 1974. I have used multiple classification analysis (MCA), since the provider variable formed from the information on medical care sources is best conceptualized as being measured at a nominal level. It emphasizes both the number of different affiliations and the specialty and type of each affiliation. The MCA analysis with the provider set variable and the social, demographic, and need variables has a multiple R2 (adjusted) of 0.40. The most important explanatory variable is the number of conditions, a need variable; the next most important is the provider variable. This study demonstrates the value of variables that account for providers of care and ambulatory care patterns as well as measures of need and social and demographic variables in a complete model of utilization behavior.