Previous research on the utilization of pediatric preventive care has shown that certain sociodemographic factors, such as age, birth order, family size and race, as well as health attitudes and beliefs are related to the use of well-child services. To examine the simultaneous effects of sociodemographic, psychosocial and behavioral factors, we conducted a 16-month prospective investigation of 532 children belonging to a university-affiliated prepaired group practice. The children were under 5 years of age upon enrollment and came predominantly from white, middle-class families with well-educated parents. Our bivariable results showed that 13 factors were related to preventive care utilization (p less than 0.05) and, in effect, confirmed findings from previous investigations. However, using model-fitting procedures, we found that only two variables, child's age and birth order, significantly predicted the rate of preventive care visits; a high utilization rate was observed for younger children and for first-born children. Since the observed age-specific rates of preventive care utilization were nearly identical to the schedule recommended by the pediatricians in this practice, we believe that most of the variability in well-child care in our population was due to provider-induced demand. Furthermore, none of the other demographic or psychosocial factors that significantly predicted acute care utilization in this population had any effect on preventive care once age and birth order were accounted for.