To examine the association between state Medicaid vaccine administration fees and children’s receipt of immunization services.
The study used the 2008–2012 Medicaid Analytic eXtract data and included children aged 0–17 years and continuously enrolled in a Medicaid fee-for-service plan in each study year. Analyses were restricted to 8 states with a Medicaid managed-care penetration rate <75%. Linear regressions were used to estimate the probability of children making ≥1 vaccination visit and the numbers of vaccination visits in the year as a function of state Medicaid vaccine administration fees, age group, sex, race/ethnicity, state unemployment rate, state managed-care penetration rate, and state and year-fixed effects.
A total of 1,678,288 children were included. In 2008–2012, the average proportion of children making ≥1 vaccination visit per year was 31% and the mean number of vaccination visits was 0.9. State Medicaid reimbursements for vaccine administration was positively associated with immunization service utilization; for every $1 increase in the payment amount, the probability of children making ≥1 vaccination visit increased by 0.72 percentage point (95% confidence interval, 0.23–1.21; P=0.01), representing a 2% increase from the mean and the number of vaccination visits increased by 0.03 (95% confidence interval, −0.00 to 0.06; P<0.1). The estimated effect was greater among younger children.
Higher Medicaid reimbursements for vaccine administration were associated with increased proportion of children receiving immunization services.