The transition from Medicaid fee-for-service to managed care among private practitioners in New York City: effect on immunization and screening rates.

OBJECTIVES: This study examined the association between participation in Medicaid managed care and up-to-date coverage for childhood immunizations and screenings among private practice physicians serving New York City's poorest neighborhoods. METHOD: A random sample of 2174 children 3-35 months of age was drawn from 60 physician practices in 1995, and a cross-sectional analysis was used to compare up-to-date status for immunizations, and lead and anemia screening tests, for children cared for by managed care and nonmanaged care physicians. In 1996, an independent sample of 2380 children from the same practices was used to compare up-to-date status for individual children enrolled in Medicaid managed care and children predominantly enrolled in traditional fee-for-service Medicaid. Information from physician interviews augmented chart review data. Chi-square analysis and logistic regression were used. RESULTS: Physicians who participate in Medicaid managed care and those who do not had equal up-to-date coverage for immunizations (41.0 vs. 36.9%, p = .527), and lead (46.8 vs. 38.7%, p = .199) and anemia screening (63.2 vs. 56.5%, p = .272). Measures of the process of care were also similar for the two groups of physicians. Children themselves enrolled in Medicaid managed care appeared significantly more likely to be up-to-date than their nonmanaged care counterparts for immunizations (OR = 1.53, p = .027) and anemia screening (OR = 2.95, p = .000). CONCLUSIONS: Participation in managed care does not seem to change physicians' overall preventive care practice behavior. Available data did not reveal major differences in demographics or health status between individual children enrolled in managed care and those not enrolled. That children enrolled in managed care were better immunized and screened than those in fee-for-service Medicaid suggests that physicians receiving compensation under two payment systems may treat children differently depending on each child's mode of reimbursement.