title: Human papilloma virus vaccination programs reduce health inequity in most scenarios: a simulation study.
abstract: BACKGROUND
  The global and within-country epidemiology of cervical cancer exemplifies health inequity. Public health programs may reduce absolute risk but increase inequity; inequity may be further compounded by screening programs. In this context, we aimed to explore what the impact of human papillomavirus (HPV) vaccine might have on health equity allowing for uncertainty surrounding the long-term effect of HPV vaccination programs.
  
  
  METHODS
  A simple static multi-way sensitivity analysis was carried out to compare the relative risk, comparing after to before implementation of a vaccination program, of infections which would cause invasive cervical cancer if neither prevented nor detected, using plausible ranges of vaccine effectiveness, vaccination coverage, screening sensitivity, screening uptake and changes in uptake.
  
  
  RESULTS
  We considered a total number of 3,793,902 scenarios. In 63.9% of scenarios considered, vaccination would lead to a better outcome for a population or subgroup with that combination of parameters. Regardless of vaccine effectiveness and coverage, most simulations led to lower rates of disease.
  
  
  CONCLUSIONS
  If vaccination coverage and screening uptake are high, then communities are always better off with a vaccination program. The findings highlight the importance of achieving and maintaining high immunization coverage and screening uptake in high risk groups in the interest of health equity.
authors.affiliation: Infectious Diseases, Public Health Ontario, 480 University Avenue, Suite 300, Toronto, Ontario M5G 1V2, Canada. Natasha.crowcroft@oahpp.ca
authors.forename: Natasha S
authors.initials: NS
authors.lastname: Crowcroft
authors.forename: Jemila S
authors.initials: JS
authors.lastname: Hamid
authors.forename: Shelley L
authors.initials: SL
authors.lastname: Deeks
authors.forename: John
authors.initials: J
authors.lastname: Frank
mesh_terms: D003198:Computer Simulation; D055088:Early Detection of Cancer / Q000706:statistics & numerical data; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D017589:Immunization Programs; D008962:Models, Theoretical; D030361:Papillomavirus Infections / Q000517:prevention & control*; D053918:Papillomavirus Vaccines / Q000008:administration & dosage*; D015397:Program Evaluation; D018570:Risk Assessment / Q000379:methods; D002583:Uterine Cervical Neoplasms / Q000517:prevention & control*
chemical_list: D053918:Papillomavirus Vaccines