Factors associated with the human papillomavirus (HPV) vaccination across three countries following vaccination introduction

- The strongest predictor of HPV vaccination status is parents' HPV knowledge.
- Very low and very high parental HPV knowledge scores were associated with decreased vaccination uptake.
- Parents from the US are more worried about HPV vaccination side-effects than parents from the UK or Australia.

Direct international comparisons which aim to understand how factors associated with human papillomavirus (HPV) vaccine initiation and attitudes towards the HPV vaccination in parents differ are scarce. Parents (n = 179) of daughters aged 9-17 years in the US, UK and Australia completed an online survey in 2011 with questions measuring daughters' HPV vaccination status, HPV knowledge, HPV vaccination knowledge, and statements assessing attitude towards the HPV vaccine. The strongest factor associated with vaccination status across all countries was parental HPV knowledge (p < 0.001). Parents with both very low and very high knowledge scores were less likely to have vaccinated their daughters. Parents with higher HPV vaccination knowledge scores intended to vaccinate their daughters (if not already vaccinated) for protective reasons (p < 0.001), while those whose daughters were already vaccinated understood that vaccination protection was not 100% and that their daughters may still be at risk of getting HPV (p < 0.05). Compared to the UK and Australia, a higher proportion of parents with unvaccinated daughters from the US were worried about the side-effects of the HPV vaccination (US: 60.5%, UK: 36.4%, AUS: 15.4%; p < 0.05), believed that getting the vaccination might be a hassle (US: 21.1%, UK: 0%, AUS: 7.7%; p < 0.05), and that the vaccine was too new (US: 44.7%, UK: 22.7%, AUS: 7.7%; p < 0.05). This study adds to the understanding of how parents may influence vaccination uptake by demonstrating the effect of knowledge and the parental attitudes towards HPV vaccination across three countries.