Predictors of Human Papillomavirus Vaccination in a Large Clinical Population of Males Aged 11 to 26 years in Maryland, 2012 - 2013.

Background: Despite the recommendation for routine human papillomavirus (HPV) vaccination in males, coverage estimates remain low. We sought to identify predictors of receiving each HPV vaccine dose among a large clinical population of males. Methods: We conducted a cross-sectional analysis of electronic medical records for 14,688 males ages 11 to 26 years attending 26 outpatient clinics (January 2012-April 2013) in Maryland to identify predictors of each HPV vaccine dose using multivariate logistic regression models with generalized estimating equations. All analyses were stratified in accordance with vaccine age recommendations: 11 to 12 years, 13 to 21 years, and 22 to 26 years. Analyses of predictors of receipt of subsequent HPV doses were also stratified by the number of clinic visits (<= 3 and >3). Results: Approximately 15% of males initiated the HPV vaccine. Less than half of males eligible received the second and third doses, 49% and 47%, respectively. Non-Hispanic black males (vs. non-Hispanic white) ages 11 to 12 and 13 to 21 years and males with public insurance (vs. private) ages 13 to 21 years had significantly greater odds of vaccine initiation, but significantly decreased odds of receiving subsequent doses, respectively. Attendance to > 3 clinic visits attenuated the inverse association between public insurance and receipt of subsequent doses. Conclusion: Overall, rates of HPV vaccine initiation and of subsequent doses were low. While non-Hispanic black and publicly insured males were more likely to initiate the HPV vaccine, they were less likely to receive subsequent doses. Impact: Tailoring different intervention strategies for increasing HPV vaccine initiation versus increasing rates of subsequent doses among males may be warranted. (C) 2015 AACR.