Catch-up HPV vaccination status of adolescents in relation to socioeconomic factors, individual beliefs and sexual behaviour.

In 2012, human papillomavirus (HPV) vaccination was introduced free of charge in the Swedish national school-based vaccination programme for 10-12-year-old girls, and as catch-up vaccination for young women. In Sweden, there is an ongoing discussion about including boys in the national vaccination programme. Few studies are undertaken about adolescents' knowledge, beliefs and HPV vaccination status in relation to socioeconomic status and sexual experience. Thus, the aim was to examine HPV catch-up vaccination status in adolescents in relation to 1) socioeconomic factors, 2) beliefs and knowledge about HPV prevention, and 3) sexual behaviour. The Health Belief Model was used as a theoretical framework. Upper secondary school students (n = 832) aged 16, randomly chosen from a larger sample, were invited to participate in conjunction with the general health interview with the school nurse. A total of 751/832 (90.3%), girls (n = 391, 52%) and boys (n = 360, 48%) completed the questionnaire. HPV vaccination was associated with ethnicity and the mothers' education level; i.e. girls with a non-European background and girls with a less educated mother were less likely to have received the vaccine (p<0.01 and p = 0.04 respectively). Vaccinated girls perceived HPV infection as more severe (p = 0.01), had more insight into women's susceptibility to the infection (p = 0.02), perceived more benefits of the vaccine as protection against cervical cancer (p<0.01) and had a higher intention to engage in HPV-preventive behaviour (p = 0.01). Furthermore, boys and girls were almost equally sexually experienced, although fewer girls had used condom during first intercourse with their latest partner (p = 0.03). Finally, HPV vaccinated girls were less likely to have unprotected sex (p