Learning Objectives for this Presentation:
By the end of the presentation participants will be able to understand the variation across states in Medicaid enrollment and effectiveness in achieving high vaccination coverage.

Background:
Understanding the interplay of Medicaid and immunization services may help identify opportunities to improve immunization coverage in an economically disadvantaged population.

Objectives:
To estimate by state, the percentage of 2-year-old children enrolled in Medicaid and the gap between vaccination coverage of children enrolled in Medicaid and children privately insured.

Methods:
We used data collected between July 2001 and Dec 2002 by the NIS , health insurance module(NIS/HIM). This module contained an item regarding current enrollment in Medicaid. We estimated percent of children 19-35 currently enrolled in Medicaid at the time of the NIS interview and estimated vaccination coverage of Medicaid enrolled versus privately insured children for the combination of 4 DTaP, 3 Polio, 1 Measles containing, 3 HIB and 3 HepB vaccines (4:3:1:3:3), for each state and the District of Columbia.

Results:
The percent of children reported to be currently on Medicaid at the time of their NIS interview varied by state from 14.7 to 51.4 . The difference between 4:3:1:3:3 coverage of Medicaid versus privately insured children varied from -22.2 to 19.8 percentage points. In seven states, the vaccination coverage of Medicaid enrolled children was significantly lower than coverage for privately insured children.

Conclusions:
States vary widely in the percentage of 2-year-old children served by Medicaid and in the gap between vaccination coverage of Medicaid enrolled versus privately insured children. Identifying states where Medicaid plays a large role and where gaps are significant is a first step in understanding the causes of poor immunization coverage and creating effective partnerships to close the gaps in coverage.