On-time, late, or never: Incorporating intersectionality to predict age-specific probabilities of initiating the HPV vaccine series.

The HPV vaccine's effectiveness in protecting against the human papillomavirus (HPV) is dependent on both the timing of vaccine initiation (by age 12) and number of vaccine doses. This study used an intersectional approach to examine how gender and its intersection with race/ethnicity predict age-specific probabilities of initiating HPV vaccinations for boys/men and girls/women across four racial/ethnic groups: non-Latinx (NL) white, NL-Black, Latinx, and NL-Asian American. Multinomial logistic regression models-with on-time vaccination as the base outcome-examined the timing of initiating HPV vaccinations (never or late) in the 2011-2016 National Health and Nutrition Examination Survey (NHANES). This study finds that the multiplicative interaction term between gender and race/ethnicity produces significant results in the likelihood of initiating HPV vaccine uptake: NL-Asian American boys/men have the highest risk of not vaccinating on time. This finding would have been hidden with a one-dimensional analysis.