INSURANCE STATUS AND VACCINATION COVERAGE AMONG US PRESCHOOL CHILDREN J. M. Santoli, A. Mokdad, L. Barker, L. E. Rodewald, L. Olson, N. Halfon National Immunization Program, CDC, Atlanta, GA; American Academy of Pediatrics, Elk Grove Village, IL; Department of Pediatrics, UCLA, Los Angeles, CA

BACKGROUND: Use of pediatric health services varies with insurance status. To date, national studies have not examined the relationship between provider-verified vaccination data and insurance status among children.

OBJECTIVE: Determine the association between vaccination coverage and insurance status in a national sample of preschool children.

DESIGN/METHODS: The National Immunization Survey (NIS) is a random-digit dialing telephone survey of parents of 19-35 mo children with provider-verified vaccination data. Between 1-6/2000, NIS was conducted along with the National Survey of Early Childhood Health (NSECH), a survey of parents of 4-35 mo children. Analysis was limited to children enrolled in NIS and NSECH. Data were weighted to represent all US preschoolers, including an adjustment for non-telephone households.

RESULTS: Of 945 children in both surveys, 31% had Medicaid/CHIP coverage, 62% had other insurance, and 7% were uninsured. Factors associated with insurance status included ethnicity, first-born status, income, family size, maternal education, WIC participation, having moved from another state, and interruption in phone service. Provider-verified vaccination data were available for 665 (70%) children, a subset whose demographic profile was similar to that of the total sample. Vaccination coverage (4:3:1:3 at time of survey) was 60% for children in Medicaid/CHIP, 82% for those with other insurance, and 66% for uninsured children. In multiple logistic regression including the sociodemographic factors above, child's age/gender, and maternal age, insurance status was no longer a significant predictor of vaccination coverage. Findings were similar in more parsimonious models and when the outcome variable was timely vaccination coverage (4:3:1:3 by 24 mo).

CONCLUSIONS: Using provider-verified vaccination data, we found a large disparity in vaccination by insurance status. This disparity did not remain in multivariate analyses, but bivariate vaccination coverage differences suggest the importance of targeting Medicaid/CHIP and uninsured children to improve immunization delivery. The Vaccines for Children Program (VFC) serves both groups and is an important mechanism for quality improvement.