Do State Laws Granting Pharmacists Authority to Vaccinate Increase HPV Vaccination Rates Among Adolescents?
Human papillomavirus (HPV) vaccination rates are below the Healthy People 2020 target and rates of other recommended adolescent vaccinations. Recently, the President’s Cancer Panel and National Vaccine Advisory Committee recommended expanding HPV vaccinations to pharmacies as one strategy to improve vaccination coverage. This study tests whether state laws that allow pharmacists to give HPV vaccinations to adolescents are associated with a higher likelihood of HPV vaccination.
METHODS
Data
The National Immunization Survey-Teen is an annual, nationally-representative survey to estimate current vaccine coverage for adolescents ages 13 to 17. We examined provider-reported HPV vaccination for years following recommendation by the Advisory Committee on Immunization Practices: 2008 to 2013 for girls and 2010 to 2013 for boys.
We reviewed laws governing pharmacist vaccine authority during this period from each state’s pharmacy practice statutes. Statutes were identified and coded using the Robert Wood Johnson Foundation LawAtlas database, LexisNexis, and the American Pharmacists Association and National Alliance of State Pharmacy Associations State Immunization Authority Annual Survey.
Measures
Outcome variables were indicators for HPV vaccine series initiation (>1 dose) and completion (>3 doses) as reported by a health care provider. The explanatory variable of interest was an indicator for state-years when pharmacists were allowed to give HPV vaccinations to adolescents. We also analyzed a categorical variable for the type of pharmacist authority: not permitted (reference), by prescription only, by collaborative practice protocol, or independent authority.
Analysis
Difference-in-difference linear probability models were estimated to identify the impact of changes in state-level pharmacist vaccination authority on individual HPV vaccination. Fifteen states passed pharmacist provision laws and 22 states did not have pharmacist provision laws between 2008 and 2013. States with pharmacist provision laws for the entire study period were excluded (N=14). We ran separate models for boys (N=24,667) and girls (N=41,435), HPV vaccine initiation and completion outcomes, and for both measures of pharmacist authority laws (8 total models). All models adjusted for state and year fixed effects, state-specific time trends, state-level school entry requirements for meningococcal and Tdap vaccines, and the following individual-level covariates: age, race/ethnicity, receipt of flu, meningococcal, and Tdap vaccinations, number of health care visits in past year, household size, number of children in household, mother’s education, insurance status, and family income. Analyses were weighted using the provider-reported sample weights in NIS-Teen and standard errors were clustered by state.
RESULTS
Pharmacist provision laws were not associated with the probability of HPV vaccine initiation or completion among girls or initiation among boys in any specification. However, among boys, independent authority was associated with a 3.5 percentage point (standard error = 0.8) increase in the probability of HPV vaccine completion.
CONCLUSION
State laws that allow pharmacists to give HPV vaccinations to adolescents with full, independent authority appear to be an effective policy to increase HPV vaccine completion rates among boys.