HPV Vaccine Secondary Acceptance: Turning No into a Yes!

Context: The human papillomavirus (HPV) vaccine is recommended starting at age 9 to reduce risk of HPV linked squamous cell cancers, yet recent data shows that only 58.6% have been vaccinated by age 17. Secondary acceptance is agreeing to a vaccine subsequent to declining in a previous encounter. Existing research on secondary acceptance has focused on demographics and initial declination with little evidence around factors associated with increased rates of secondary acceptance.

Objective: Identify patient, provider, and healthcare process and utilization factors associated with rates of secondary acceptance of the HPV vaccine.

Study Design and Analysis: Retrospective cohort analysis of electronic health record data and chart review with chi square testing of the association of secondary acceptance of the HPV vaccine with child, clinician, healthcare processes.

Setting or Dataset: Academic primary care system pediatric and family medicine clinics

Population Studied: 366 randomly sampled medically-homed children who did not receive the HPV vaccine at or prior to their 11 year old well child check between March 1st 2015 and February 29th 2016

Intervention/Instrument: N/A

Outcome Measures: Initiating HPV vaccination series by the 15th birthday after declining the vaccine at 11 year old well child check.

Results: Of children who did not receive the HPV vaccine at their 11-year old well child check, 72% initiated the series before 15 years of age. Greater likelihood of secondary acceptance was associated with attending more well child visits between age 11 and 15 (p<0.01), having a documented recommendation for the HPV vaccine from staff or a clinician at the 11 year old well child check (p<0.01), and the absence of a signed HPV vaccine refusal form at the 11 year old well child check (p<0.01). Rates of secondary acceptance were higher regardless of whether recommendations were made by clinicians or staff than when no recommendation was given. Child (e.g., sex or race) and clinician (sex and specialty) characteristics were not significantly associated with rates of secondary acceptance.

Conclusions: Our findings suggest that interventions available to health systems, such as improving well child visit continuity and continuing to recommend vaccines due at each visit could increase HPV vaccination rates. Future work should evaluate such interventions or further examine additional factors that may be associated with secondary acceptance of HPV vaccine.