title: Sociodemographic Differences in Human Papillomavirus Vaccine Initiation by Adolescent Males.
abstract: OBJECTIVE
  The purpose of this study was to describe patterns of human papillomavirus (HPV) vaccine initiation by males and characterize sociodemographic differences.
  
  
  METHODS
  We conducted a retrospective cohort study of 11- to 18-year-old males in a large primary care network who had a preventive or acute visit between October 2009 and December 2013. Outcomes measured were HPV vaccine series initiation and initiation at the first eligible visit. Logistic regression measured independent associations between outcomes and sociodemographic characteristics, adjusting for potential confounders including visit frequency, insurance changes, and the presence of complex medical conditions.
  
  
  RESULTS
  Of 58,757 eligible patients, most were white (57%) with private insurance (77%). During the study period, 39% of the cohort initiated the vaccine series, and 7% initiated at their first eligible visit. Black patients with private (adjusted odds ratio [aOR], 1.99; 95% confidence interval [CI], 1.73-2.30) and Medicaid insurance (aOR, 2.90; 95% CI, 2.56-3.30) had significantly higher odds of HPV vaccine initiation compared with white patients with private insurance. A similar trend was found for Hispanic patients with private (aOR, 1.45; 95% CI, 1.26-1.67) and Medicaid insurance (aOR, 2.15; 95% CI, 1.78-2.60). These differences were present both in the preroutine recommendation period (2009-2011) and the postroutine recommendation period (2012-2013).
  
  
  CONCLUSIONS
  Traditionally marginalized populations have higher odds of HPV vaccine initiation, both at the first eligible visit and overall. Although the true mechanism underlying these differences remains unknown, potential candidates include provider recommendation patterns and differential vaccine acceptance within these groups.
authors.affiliation: Jordan Medical Education Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania. Electronic address: aagawu@mail.med.upenn.edu.
authors.forename: Atu
authors.initials: A
authors.lastname: Agawu
authors.affiliation: Department of Family and Community Health, University of Pennsylvania School of Nursing, Philadelphia, Pennsylvania.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Buttenheim
authors.affiliation: Center of Excellence for Diversity in Health Education and Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Biostatistics Analysis Center, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Lynne
authors.initials: L
authors.lastname: Taylor
authors.affiliation: Center for Pediatric Clinical Effectiveness and PolicyLab, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Healthcare Analytics Unit, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
authors.forename: Lihai
authors.initials: L
authors.lastname: Song
authors.affiliation: Jordan Medical Education Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Center for Pediatric Clinical Effectiveness and PolicyLab, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Division of General Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Fiks
authors.affiliation: Jordan Medical Education Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Center for Pediatric Clinical Effectiveness and PolicyLab, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; Division of Infectious Diseases, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
authors.forename: Kristen A
authors.initials: KA
authors.lastname: Feemster
mesh_terms: D000293:Adolescent; D002648:Child; D006801:Humans; D016015:Logistic Models; D008297:Male; D030361:Papillomavirus Infections / Q000208:ethnology / Q000517:prevention & control*; D053918:Papillomavirus Vaccines; D011320:Primary Health Care / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D014481:United States; D014611:Vaccination / Q000706:statistics & numerical data*
chemical_list: D053918:Papillomavirus Vaccines
keywords: Human papillomavirus; Immunization; Papillomavirus vaccines