BACKGROUND:
Children who do not have health insurance are often considered to be at risk of being undervaccinated.

OBJECTIVE:
To explore the association between vaccination coverage and insurance status.

METHOD:
N=24,514 children 19-35 months sampled by the NIS between 2001-2002. A child was insured if they were covered by private health insurance, Medicaid, S-CHIP, military health care, Title 5, Indian Health Service, or any other health insurance; uninsured if they were not covered by any of these insurance types; and underinsured if they were insured but their health insurance did not cover all of the cost of immunizations, or, if at least some vaccinations were not covered by their insurance. Children were up-to-date (UTD) if they had 4+ DTaP, 3+ polio, 1+ MMR, 3+ Hib, and 3+ hep B vaccine doses.

RESULT:
Nationally, 6.4% were uninsured. Uninsured children were less likely to be UTD than insured children with private insurance (61.2% vs. 78.3%, p<0.01). Nationally, 12.1% were underinsured. Underinsured children were as likely to be UTD as insured children who had private insurance (78.2% vs. 78.3%, p>0.05). Among underinsured children, children with low vaccination coverage were (i) Hispanic, non-Hispanic white, and Native-American children living in a household with income-to-poverty ratio <2.27 and whose mother was <22 years old when they gave birth to their child; and (ii) children whose mother was divorced, had less than a high school or college degree, and gave birth to their child after 23 years of age. These underinsured children had lower vaccination coverage compared to privately insured children (55.7% vs. 78.3%, p<0.01) and were 12.8% of all underinsured children.

CONCLUSION:
Being uninsured is an important barrier to being UTD, as is underinsurance among certain socio-demographic groups.

LEARNING OBJECTIVES:
To learn how insurance status effects vaccination coverage.