Human papillomavirus vaccination of girls in the German model region Saarland: Insurance data-based analysis and identification of starting points for improving vaccination rates

Abstract

In Germany, the incidence of cervical cancer, a disease caused by human papillomaviruses (HPV), is higher than in neighboring European countries. HPV vaccination has been recommended for girls since 2007. However, it continues to be significantly less well received than other childhood vaccines, so its potential for cancer prevention is not fully realized. To find new starting points for improving vaccination rates, we analyzed pseudonymized routine billing data from statutory health insurers in the PRÄZIS study (prevention of cervical carcinoma and its precursors in women in Saarland) in the federal state Saarland serving as a model region. We show that lowering the HPV vaccination age to 9 years led to more completed HPV vaccinations already in 2015. Since then, HPV vaccination rates and the proportion of 9- to 11-year-old girls among HPV-vaccinated females have steadily increased. However, HPV vaccination rates among 15-year-old girls in Saarland remained well below 50% in 2019. Pediatricians vaccinated the most girls overall, with a particularly high proportion at the recommended vaccination age of 9-14 years, while gynecologists provided more HPV catch-up vaccinations among 15-17-year-old girls, and general practitioners compensated for HPV vaccination in Saarland communities with fewer pediatricians or gynecologists. We also provide evidence for a significant association between attendance at the children´s medical check-ups "U11" or "J1" and HPV vaccination. In particular, participation in HPV vaccination is high on the day of U11. However, obstacles are that U11 is currently not financed by all statutory health insurers and there is a lack of invitation procedures for both U11 and J1, resulting in significantly lower participation rates than for the earlier U8 or U9 screenings, which are conducted exclusively with invitations and reminders. Based on our data, we propose to restructure U11 and J1 screening in Germany, with mandatory funding for U11 and organized invitations for HPV vaccination at U11 or J1 for both boys and girls.

Fig 1. Numbers, rates, and timely finalisation of HPV vaccinations in females.

(A) Numbers (absolute frequencies) of the first HPV vaccination by age and years of females in Saarland (KVS data 2014–2019). (B) Rates of fully vaccinated 15-year-old girls in Saarland. Percentage representation of the relative frequencies (data KVS 2015–2019). (C) Timely completion of HPV vaccination. Shown is the proportion of females with EBM code 89110B indicating the final HPV vaccination dose before or after the first date for counselling in the context of conception regulation (EBM code 01821, data KVS 2013–2019), smear collection in the context of conception regulation (EBM code 01825, data KVS 2013–2019), contraceptive prescription (EBM code 01820, data AOK 2009–2018), or pregnancy detection (EBM code 32132, data KVS 2013–2019). Percentage representation of relative frequencies. (D) Average number (absolute frequencies) of physician visits in billing years 2013 to 2019 for female individuals reaching the specified age in 2019 who received no HPV vaccination or at least one HPV vaccination (EBM code 89110A/B, KVS billing data, 2013–2019). Confidence intervals are shown in S9 Table.

Fig 2. Relationship between HPV vaccination and vaccinating medical specialists.

(A) Cartographic distribution of the vaccinating doctors by medical specialty (gynecologists, pink; pediatricians, yellow; general practitioners, blue; internists, red) based on Saarland municipality and per 10,000 inhabitants (data KVS 2013–2019). Administrative boundaries from © GeoBasis-DE / BKG 2020; Data License Germany—Attribution—Version 2.0; Terms of use: http://sg.geodatenzentrum.de/web_public/nutzungsbedingungen.pdf. (B) Cartographic distribution of HPV vaccination doses by medical specialty and by Saarland municipalities, weighted according to the number of inhabitants (data KVS 2013–2019). (C) Administration of HPV vaccinations (total 61,261, left chart) or booster vaccinations (diphtheria, pertussis, tetanus, poliomyelitis, total 264,946, right chart) by different specialist groups. Percentage representation of relative frequencies in pie chart (data KVS 2013–2019). (D) Administration of HPV vaccine doses by medical specialty and age of vaccinees. Presentation of absolute frequencies (data KVS 2013–2019).

Fig 3. Relationship between HPV vaccination and participation in medical check-ups.

(A) Number (absolute frequencies) of preventive medical check-ups among female individuals in Saarland (data KVS 2013–2019). (B) U11 participation rates for girls of birth cohorts 2004–2007. Percentage representation of relative frequencies (obtained from a linked IKK-KVS data set, 2013–2019). (C) J1 Participation rates for female individuals of birth cohorts 2001–2005. Percentage representation of relative frequencies (data KVS 2013–2019). Utilisation of the U11 (D) or J1 (E) appointment for HPV vaccination by females in the year of U11 or J1, respectively. Percentage representation of relative frequencies. Data in (D) were obtained from a linked IKK-KVS data set, 2013–2019; data in (E) from KVS 2015–2019.