Human Papillomavirus (HPV) is a leading cause of sexually transmitted diseases, with more than 70% of sexually active people getting the virus at least once in their lifetimes. Persistent infection with some HPV strains can lead to cervical cancer, the second most common cancer in women, as well as to head-and-neck and other types of cancer and anogenital warts in both men and women.

Current HPV vaccines have been shown to be safe and virtually 100% efficacious in extensive clinical trials and use in the field, but routine vaccination targeted predominantly at young girls has generated widespread public controversy. Scientists from McGill University, the Lady Davis Institute at the Jewish General Hospital in Montreal, and Institut National de Santé Publique du Québec have identified key determinants in parents' decision-making about HPV vaccination of their daughters. Their results have been published in Human Vaccines & Immunotherapeutics.

774 Quebec parents of 9- to 10-year-old girls eligible to a local free school-based HPV vaccination program responded to a mail-in questionnaire, and their answers were analyzed in the framework of the Health Belief Model, which dissects decision-making into five factors: perceived susceptibility to and severity of HPV infection, perceived benefits and barriers of vaccination, and cues to action, i.e., external influences promoting vaccination.

Parents who had their daughters vaccinated (88%) differed from those who did not do so in perceived susceptibility to the disease, benefits and barriers of the vaccine, and cues to action. "Parents who accepted were more trusting of the public health program, more likely to have their physician's recommendation, and wanted to protect their daughters' health. Parents who declined were more likely to be concerned about side effects and safety of the vaccine," says senior author Zeev Rosberger, Director of the Louise Granofsky-Psychosocial Oncology Program and Senior Investigator at the Lady Davis Institute of the Jewish General Hospital.

While most studies on HPV vaccine decision-making focus on parents' intentions, this was a post-recommendation, population-based survey of actual uptake, which revealed additional information. "Parents who had refused reported fear of side effects and low risk of infection to their young daughters. Parents who accepted as well as refused both reported having unanswered questions, doubts and inaccurate information."

The researchers hope that their study can be generalized for guiding efforts to increase HPV vaccine uptake. "Physician recommendation is one of the most important sources of influence for most parents. Having a free, easily accessed (school-based, public health) program helps. But there also needs to be an emphasis on assuring parents about safety concerns and an easily accessible place for parents to receive accurate information and have their questions answered both pre- and post-vaccination," concludes Dr. Rosberger.

Given the very high efficacy and excellent safety record of HPV vaccines, the key to fully exploiting these vaccines to prevent infection and consequent HPV-linked cancers lies in achieving a much higher rate of vaccination, for which studies of this type point a way to improvement.

Both the quantitative and qualitative studies are available to access for free for a limited time.