We assessed the association of state legislation with adolescent human papillomavirus (HPV) vaccination rates in states that legislated information dissemination or administration of HPV vaccination. Using insurance claims, we calculated monthly HPV vaccination rates (November 2009-December 2017) among adolescents in states that passed HPV vaccination legislation during that period: Missouri (July 2010), Kentucky (February 2012), Indiana (March 2013), Oregon (June 2013). We used segmented regression to estimate levels and trends of HPV vaccination rates, comparing pre-legislation to post-legislation segments, adjusting for seasonal vaccination patterns and changes to the vaccination recommendation among males during the study period. Indiana's legislation allowed pharmacists to administer HPV vaccination; legislation in Kentucky, Missouri, and Oregon included provisions HPV and cervical cancer education. No statistically significant increases in HPV vaccination levels or trends were observed in the post-legislation segments among adolescents overall; however, a significant post-legislation increase in vaccination trends was observed among boys in Missouri (β = 0.16, p = 0.03). Evidence for a positive impact of legislation on HPV vaccination rates is limited. The scarcity of policies that directly facilitate or promote HPV vaccination, and the breadth of exemptions to school vaccination requirements, may limit the effectiveness of these policies. Continuing efforts to introduce and pass legislation that directly facilitates HPV vaccination, combined with promoting existing evidence-based interventions, can provide opportunities to identify the most effective strategies to increase adolescent HPV vaccination rates.
Keywords: Adolescents; Human papillomavirus; Legislation; Policy; Segmented regression; Time series analysis; Vaccination.