The Impact of State Policies on Vaccine Coverage by Age 13 in an Insured Population

Abstract

Purpose To determine the impact of state policies on vaccine coverage among adolescents with managed care insurance. Methods We used the 2003 Health Plan Employer Data and Information Set to determine state-specific hepatitis B and varicella vaccine coverage among children with managed care insurance who turned 13 years in 2002. Our outcomes of interest were receipt of hepatitis B and varicella vaccines by age 13. Utilizing weighted least-squares methods, multiple linear regression models were developed to evaluate the relationship between hepatitis B and varicella vaccine coverage and state policies, while controlling for state sociodemographic variables. Results Across 28 states, adolescent hepatitis B vaccine coverage ranged from 35.3% to 80.5% (mean = 55.3%) and varicella vaccine coverage ranged from 22.9% to 7.6% (mean = 42.3%). In separate multiple regression models, after adjusting for potentially confounding sociodemographic variables, middle school mandates were significantly associated with hepatitis B vaccine coverage ( p = .002) and varicella vaccine coverage ( p = .024). Other policies, including universal purchase of vaccines and availability of philosophic exemptions, were not associated with vaccine coverage in this insured population. Conclusions In this population of insured adolescents, middle school vaccine mandates were the only state policy associated with improved hepatitis B and varicella vaccine coverage. Mandates are an effective method for promoting adolescent immunization.