ARCHIVED - Recommendations on a Human Papillomavirus Immunization Program

6. Acceptability of HPV immunization

6.1 International Studies

Most published studies emphasize the public's low level of knowledge about HPV, especially its prevalence and links to cervical cancer(44-52). Despite this lack of knowledge, there is significant public interest in HPV vaccines. The intention to be vaccinated against HPV is common among female adolescents and young women(49,50,53-61), as well as among parents for their young adolescents(45,46,52-55,61-65).

Several factors influence attitudes about HPV vaccination. The most salient issues are vaccine efficacy and safety; perceived risk and severity of the disease; recommendation by a physician; and, for health care providers, professional society recommendation. Health care providers are the most likely people to influence parental decisions regarding vaccination. They are also the main source of information on HPV vaccination for the public.

6.2 Canadian studies

In a national study to determine parental intention to vaccinate their daughters with the HPV vaccine, parents of children aged 8 to 18 were recruited from across Canada between June 2006 and March 2007 through random digit dialing(66). Participants were asked to respond to a series of questions in the context of a grade 6 (age 11-12 years), publicly funded, school-based HPV vaccine program, including their intention to have their daughter vaccinated with the HPV vaccine. Parents were also asked about a series of characteristics known to predict intention to vaccinate, including attitudes towards vaccination, perceptions about the role of the HPV vaccine in influencing sexual behaviour, social norms, up take of childhood vaccines, knowledge of HPV and cervical cancer, as well as demographic characteristics. Backwards logistic regression was conducted to calculate adjusted odds ratios (OR) in order to identify the factors that predict parents' intention to have their daughter(s) vaccinated against HPV.

Of the 1,350 respondents, over 70% (73.8%, 95% confidence interval [CI]: 71.9%-75.7%) reported that they intended their daughter to be vaccinated against HPV. Across the country, in crude analysis, intention to vaccinate in different regions of residence ranged from 62.8% (95% CI 60.2%-65.4%) in British Columbia to a high of 82.6% (95% CI 80.6%-84.6%) in Atlantic Canada (p < 0.01). In multivariable modeling, parents who had positive attitudes towards vaccines (OR = 9.9, 95% CI: 4.7-21.1), parents who were influenced by subjective norms (OR = 9.2, 95% CI: 6.6-12.9), parents who felt that the vaccine had limited influence on sexual behaviour (OR = 3.2, 95% CI: 2.2-4.6) and parents who thought that someone they knew was likely to get cervical cancer (OR = 1.5, 95% CI: 1.1-2.1) were more likely to intend to have their daughters vaccinated with the HPV vaccine. Parents who were older compared with those who were younger (OR = 0.6, 95% CI: 0.5-0.8) and parents who resided in British Columbia compared with Atlantic Canada (OR = 0.5, 95% CI: 0.3-0.9) were less likely to do so.

The most important predictor of parental intention to vaccinate was the psychological construct assessing parental attitudes towards vaccines in general and the HPV vaccine in particular. This construct examined aspects such as HPV vaccine safety and efficacy along with overall attitudes towards vaccines. Recommendations to vaccinate from health professionals, family and friends, and community leaders, with physicians in particular, were also important predictors of parental intention to vaccinate with the HPV vaccine. In this study, cultural background, religious beliefs, specific religious affiliations and educational background were not predictors of parents' intention to have their daughters vaccinated.

Between May and November 2006, an anonymous, self-administered questionnaire was mailed to all obstetricians/gynecologists and pediatricians and to a random sample of family physicians in British Columbia, Quebec and Nova Scotia (1,268 respondents, response rate of 50.2%)(68). Overall, 28% of physicians scored = 6 on 9 knowledge questions. The mean score of obstetricians/gynecologists (5.6) was higher than that of family physicians (3.8) or pediatricians (3.2). However, most intended to recommend the HPV vaccine; 95% felt that the vaccine should be given before the onset of sexual activity; and 80% felt that the best age for vaccination was < 14 years. Overall, 88% of Canadian physicians surveyed intend to recommend the vaccine if it was publicly funded and 84% if patients had to pay for it.

*Subjective norm component represents a person's beliefs about whether relevant others think he or she should perform the behaviour and his or her motivation to comply with those others(67).