title: Dynamics of HPV vaccination initiation in Flanders (Belgium) 2007-2009: a Cox regression model.
abstract: BACKGROUND
  We investigated dynamic patterns and predictors of HPV vaccination initiation in Flanders (Belgium) by girls aged 12 to 18, between 2007 and 2009, the period immediately after the introduction of the HPV vaccines on the Belgian market. During this period the initiative for vaccination was taken by the girl, her family or the general practitioner/pediatrician/gynecologist.
  
  
  METHODS
  We used a Cox regression model with time constant and time varying predictors to model hazard rates of HPV vaccination initiation. The sample existed of 117,151 female members of the National Alliance of Christian Mutualities, the largest sickness fund in Flanders.
  
  
  RESULTS
  The study showed that the hazard of HPV vaccination initiation was higher (1) for older girls, (2) for girls with a more favorable socio-economic background, (3) under more generous reimbursement regimes (with this effect being more pronounced for girls with weak socioeconomic backgrounds), (4) for girls that were informed personally about the reimbursement rules.
  
  
  CONCLUSIONS
  When the initiative for HPV vaccination lies with the girls, their families or the physicians (no organized setting) the uptake of the vaccines is affected by both individual and organizational factors.
authors.affiliation: Herman Deleeck Centre for Social Policy, Antwerp University, St Jacobstraat 2, 2000 Antwerpen, Belgium. eva.lefevere@ua.ac.be
authors.forename: Eva
authors.initials: E
authors.lastname: Lefevere
authors.forename: Niel
authors.initials: N
authors.lastname: Hens
authors.forename: Frank
authors.initials: F
authors.lastname: De Smet
authors.forename: Pierre
authors.initials: P
authors.lastname: Van Damme
mesh_terms: D000293:Adolescent; D001530:Belgium; D002648:Child; D005260:Female; D006801:Humans; D017589:Immunization Programs / Q000706:statistics & numerical data*; D030361:Papillomavirus Infections / Q000517:prevention & control; D053918:Papillomavirus Vaccines; D016016:Proportional Hazards Models
chemical_list: D053918:Papillomavirus Vaccines