title: From non school-based, co-payment to school-based, free Human Papillomavirus vaccination in Flanders (Belgium): a retrospective cohort study describing vaccination coverage, age-specific coverage and socio-economic inequalities.
abstract: School-based, free HPV vaccination for girls in the first year of secondary school was introduced in Flanders (Belgium) in 2010. Before that, non school-based, co-payment vaccination for girls aged 12-18 was in place. We compared vaccination coverage, age-specific coverage and socio-economic inequalities in coverage - 3 important parameters contributing to the effectiveness of the vaccination programs - under both vaccination systems. We used retrospective administrative data from different sources. Our sample consisted of all female members of the National Alliance of Christian Mutualities born in 1995, 1996, 1998 or 1999 (N=66,664). For each vaccination system we described the cumulative proportion HPV vaccination initiation and completion over time. We used life table analysis to calculate age-specific rates of HPV vaccination initiation and completion. Analyses were done separately for higher income and low income groups. Under non school-based, co-payment vaccination the proportions HPV vaccination initiation and completion slowly rose over time. By age 17, the proportion HPV vaccination initiation/completion was 0.75 (95% CI 0.74-076)/0.66 (95% CI 0.65-0.67). The median age at vaccination initiation/completion was 14.4 years (95% CI 14.4-14.5)/15.4 years (95% CI 15.3-15.4). Socio-economic inequalities in coverage widened over time and with age. Under school-based, free vaccination rates of HPV vaccination initiation were substantially higher. By age 14,the proportion HPV vaccination initiation/completion was 0.90 (95% CI 0.90-0.90)/0.87 (95% CI 0.87-0.88). The median age at vaccination initiation/completion was 12.7 years (95% CI 12.7-12.7)/13.3 years (95% CI 13.3-13.3). Socio-economic inequalities in coverage and in age-specific coverage were substantially smaller.
authors.affiliation: Herman Deleeck Centre for Social Policy, University of Antwerp, St Jacobstraat 2, 2000 Antwerp, Belgium. Electronic address: eva.lefevere@uantwerpen.be.
authors.forename: Eva
authors.initials: E
authors.lastname: Lefevere
authors.affiliation: Centre for the Evaluation of Vaccination (CEV), Vaccine & Infectious Disease Institute (VAXINFECTIO), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium. Electronic address: heidi.theeten@uantwerpen.be.
authors.forename: Heidi
authors.initials: H
authors.lastname: Theeten
authors.affiliation: Center for Statistics (CenStat), Hasselt University, Agoralaan, Building 3, 3590 Diepenbeek, Belgium; Centre for Health Economics Research and Modelling Infectious Diseases (CHERMID), Vaccine & Infectious Disease Institute (VAXINFECTIO), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium. Electronic address: niel.hens@uhasselt.be.
authors.forename: Niel
authors.initials: N
authors.lastname: Hens
authors.affiliation: National Alliance of Christian Mutualities, Haachtsesteenweg 579, 1031 Brussel, Belgium; Department of Public Health and Primary Care, Environment and Health, KU Leuven, Kapucijnenvoer 35 blok D, Box 7001, 3000 Leuven, Belgium. Electronic address: frank.desmet@cm.be.
authors.forename: Frank
authors.initials: F
authors.lastname: De Smet
authors.affiliation: Agency for Care and Health, Infectious Disease Control and Vaccinations, K. Albert II laan 35 Box 33, 1030 Brussels, Belgium. Electronic address: geert.top@zorg-en-gezondheid.be.
authors.forename: Geert
authors.initials: G
authors.lastname: Top
authors.affiliation: Centre for the Evaluation of Vaccination (CEV), Vaccine & Infectious Disease Institute (VAXINFECTIO), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium. Electronic address: pierre.vandamme@uantwerpen.be.
authors.forename: Pierre
authors.initials: P
authors.lastname: Van Damme
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001530:Belgium; D002648:Child; D005260:Female; D006291:Health Policy; D006297:Health Services Accessibility; D006801:Humans; D017589:Immunization Programs; D030361:Papillomavirus Infections / Q000517:prevention & control*; D053918:Papillomavirus Vaccines / Q000008:administration & dosage* / Q000191:economics*; D012189:Retrospective Studies; D012574:Schools; D012959:Socioeconomic Factors; D014611:Vaccination / Q000191:economics* / Q000706:statistics & numerical data*
chemical_list: D053918:Papillomavirus Vaccines
keywords: Age-specific coverage; Belgium; Co-payment; Coverage; HPV vaccination; School; Socio-economic inequalities