Validity of Self-reported HPV Vaccination History in 18-26 Year Old Men Who Have Sex with Men, 2016-2018

Background Since 2011, human papillomavirus (HPV) vaccination has been recommended for men who have sex with men (MSM) through age 26 to prevent infection with the HPV types most commonly associated with cancer. Accurate estimates of HPV vaccine coverage are needed to monitor coverage and impact of HPV vaccine over time. We assessed the validity of self-report as a measure of HPV vaccination status among young MSM in the Seattle, Washington area. Methods During 2016-2018, 18-26-year-old MSM and transgender women (TGW) were enrolled at the Public Health-Seattle & King County STD Clinic and Gay City Health Project. HPV vaccination data were collected via a self-administered survey, clinic electronic medical records (EMR), and the Washington State Immunization Information System (WAIIS) vaccine registry. Serum samples were assessed for seropositivity to 4 types of HPV included in the quadrivalent HPV vaccine. We assessed the sensitivity of self-report compared to verified HPV vaccine status (documented in either the EMR or the WAIIS). We did not evaluate specificity due to known incompleteness of verified HPV vaccine status. We also assessed the positive predictive value (PPV) of self-report using seropositivity to all 4 HPV quadrivalent vaccine types as the gold standard. Additional subanalyses were conducted to assess self-report validity by age, number of doses recalled, and time since vaccination. Results There were 751 participants in this study. Most participants were aged 22-26 years (74.4%) and reported their gender identity as male (96.9%); 57.4% self-identified as white. Of the 290 participants with a verified record of HPV vaccine, 241 self-reported having received the HPV vaccine (sensitivity=83.1%, 95% CI: 78.3% to 87.2%). The likelihood of correct self-report was lower, but not statistically different, for those aged 18-21 years compared to those aged 22-26 years (OR=0.7, 95% CI: 0.4 to 1.3). In addition, compared to participants who received their first dose less than a year ago, the likelihood of correct self-report was similar for those with 1-2 years since first dose (OR=0.9, 95% CI: 0.4 to 2.1), but lower for those with more than three years since first dose (OR=0.4, 95% CI: 0.2 to 0.9). Of 369 participants who self-reported a history of HPV vaccination and had an adequate serum sample for HPV serology testing, 314 were seropositive to all 4 vaccine types (PPV=85.1%, 95% CI: 81.0% to 88.6%). PPV was highest among those with 3 or more doses (94.1%, 95% CI: 89.8% to 97.0%). Conclusions Our results suggest that self-report of HPV vaccination is a valid way of assessing HPV vaccine status among young MSM when neither vaccine registry nor medical record data are available. Our results indicating reduced recall in participants with three or more years since first vaccine dose suggest that the validity of self-report in young adult MSM may decline over time as adolescent vaccination coverage increases.