An analysis of the immunization status of preschool children enrolled in astatewide Medicaid managed care program

Objectives: To measure immunization coverage rates for children enrolled in a statewide Medicaid managed care program and determine the impact of soci odemographic characteristics and the type of primary care provider site on immunization coverage. Study design: A random sample of 2000 was chosen from children between the ages of 19 and 35 months who had been continuously enrolled in the Medicaid managed care program for 1 year. Sociodemographic data and a list of prima ry care providers Cor the study children were obtained from administrative databases. Immunization histories were deter-mined by medical record review . Results: Vaccine-specific immunization rates for diptheria-tetanus-pertussi s, polio, Haemophilus influenza type b, hepatitis B, and measles-mumps-rube lla ranged from 87% to 94%, with an overall coverage rate of 75%. Overall i mmunization status varied by primary care provider site as follows: office- based, 72%; community health center, 75%; hospital-based clinic, 79%; and s taff model health maintenance organization, 85% (chi (2) test, P = .008). Conclusions: Immunization rates compare favorably with national rates for t his low-income group. Sociodemographic characteristics were not important p redictors of underimmunization, but rates did vary by the type of primary c are provider site.