Provider and Practice Factors Associated With On-Time HPV Vaccination in Primary Care.

Background: In 2018, only one third of girls and boys completed the 2-dose series of the human papillomavirus vaccine by their 13th birthday, the target for on-time vaccination. The study objective was to identify key patient, provider and practice-level factors associated with on-time vaccination in the primary care setting.

Methods: We examined data from 20 primary care pediatric practices (89 providers) in St. Louis including: the percentage of eligible patients with on-time vaccination assessed from medical records; providers' knowledge, attitudes and behaviors regarding on-time vaccination assessed with a survey; and practice-level strategies used to optimize vaccine delivery assessed with a 19-item vaccine delivery system score (VDSS). Factors that increased on-time vaccination were identified using logistic regression, controlling for clustering within providers.

Results: Completion of on-time vaccination occurred in 1347/3125 (43.10%) of patients (95% confidence interval [CI], 41.36%-44.86%) and varied among practices (7.39%-64.24%) and among providers (2.63%-82.50%). Independent predictors for higher completion of on-time vaccination included more frequent use by providers of the announcement style for vaccine recommendation (odds ratio [OR] 1.18, 95% CI, 1.04, 1.35), higher provider self-efficacy to deliver the vaccine according to guideline recommendations if parents were hesitant (OR 1.21, 95% CI, 1.05, 1.40), and higher VDSS (OR 1.20, 95% CI, 1.10, 1.31).

Conclusions: Provider and practice-level factors were identified that may represent modifiable targets for improvement in on-time vaccine uptake. Future research is needed to test interventions built on these findings.