Stage of adoption of the human papillomavirus vaccine among college women
Introduction
Human papillomavirus (HPV) is the most common sexually transmitted infection in the US. More than 20 million women and men in the US are infected with HPV, with an estimated 6 million more becoming infected each year (Weinstock et al., 2004). Sexually active individuals between the ages of 15–24 constitute half of the infected population (Cates, 1999, Dunne et al., 2007).The majority of HPV infections are asymptomatic and clear without medical intervention. However, about 10% of women who contract “high risk” HPV types (16, 18) develop persistent infections that can cause cervical and other cancers. “Low risk” types (6, 11) can cause mild Pap test abnormalities, genital and respiratory tract warts (Ault, 2006).
A vaccine (Gardasil®) that confers protection against HPV types (6,11,16,18) responsible for 70% of cervical cancer and 90% of genital warts is now available and recommended for girls ages 11–12 (Centers for Disease Control and Prevention, 2006). It may also be administered to girls as young as age 9, and up to age 26 (Kuehn, 2006). Availability of the vaccine represents a significant step toward reducing the public health burden of HPV. However, empirical evidence suggests that mere availability will not ensure population uptake, and that those most at risk for vaccine-preventable diseases are generally the least likely to obtain them (Mays et al., 2004). Since cervical cancer often does not occur until later in life, young women may not see this as a significant health threat. Nevertheless, they are at high risk for contracting the infection.
There has been an exponential increase in the number of studies exploring acceptability of the vaccine since it became commercially available in 2006. Many studies have focused on parental willingness to vaccinate their children (Bair et al., 2008, Brabin et al., 2006, Chan et al., 2007, Constantine and Jerman, 2007, Constantine et al., 2007, Dempsey et al., 2006, Dinh et al., 2007, Gerend et al., 2006, Lenselink et al., 2008, Marlow et al., 2007, Mays et al., 2004, Noakes et al., 2006, Ogilvie et al., 2007, Sperber et al., 2008, Woodhall et al., 2007). To a lesser extent, studies have examined vaccine knowledge, attitudes and intentions of young women (Crosby et al., 2007, D'Urso et al., 2007, Gerend et al., 2006, Gerend and Magloire, 2008). Recent reviews (Brewer and Fazekas, 2007, Klug et al., 2008, Zimet et al., 2000) show that among those who are aware of the relationship between HPV and cancer, acceptance of the vaccine is high. Nevertheless, there is a need for additional information regarding the factors that influence vaccine decisions. This will inform the development of effective interventions to promote vaccine uptake among young women.
The purpose of this study was to assess factors associated with intention to obtain the vaccine among female college students. This study makes several important contributions to the existing literature. First, data were collected shortly after the vaccine became available in the U.S. As such, findings reflect a ‘snapshot’ of the early phase of vaccine dissemination. Moreover, our examination of stage of adoption represents a more nuanced outcome than ‘vaccine acceptability’ which has typically been measured as a dichotomous variable in most prior studies. Second, young women are an important target audience for the ‘catch up’ phase of vaccine distribution. Relatively few studies have explored knowledge, attitudes and intentions in this age group. Third, most studies have focused on knowledge as the key correlate or predictor of vaccine acceptability. It is well known that knowledge, while necessary, is not sufficient to motivate behavioral adoption. This study provides new insights into the cognitive, attitudinal, and normative beliefs that shape HPV vaccine intentions.
The conceptual model guiding this study incorporated multiple theories of behavior change, including the transtheoretical model of change (Prochaska and DiClemente, 1984). The Transtheoretical Model (TTM) is a psychosocial theory that predict a person's success or failure in achieving behavior change. At the center of this theory is the notion that change occurs along a continuum and that individuals vary in their stage of readiness to adopt change. Progression in stage of change is mediated by different processes. Therefore, in developing effective interventions, it is helpful to consider the stage of readiness of the individual, as well as the processes that are influential at that stage (Grimshaw and Stanton, 2006, Spencer et al., 2006, Prochaska and Velicer, 1997). We assessed relationships between stage of adoption and constructs from the Health Belief Model (Becker, 1974), Theory of Reasoned Action (Azjen and Fishbein, 1980) and Social Cognitive Theory (Bandura, 1986). Taken together, these psychosocial theories provide a useful conceptual framework for identifying key cognitive, attitudinal, and normative beliefs that shape HPV vaccine intentions and ultimately behavior. Our goal was to gather information to guide development of interventions that could be targeted to those in different stages of adoption, with acknowledgement that constructs from multiple theoretical frameworks have been salient predictors of vaccine decisions in prior research (Brewer et al., 2007, Kahn et al., 2008, Zimet et al., 2005bb). We hypothesized that participants with: (1) greater awareness and knowledge regarding HPV; (2) greater perceived susceptibility to HPV; (3) greater perceived severity of HPV; (4) greater perceived benefits of HPV vaccination; (5) fewer perceived barriers to HPV vaccination; and (6) more positive social norms (perceptions that peers are receiving vaccine); and (7) positive subjective norms (perceptions that significant others approve of HPV vaccination) would be more likely to have already obtained the HPV vaccine or strong intention to do so in the near future.
Section snippets
Sample
Women eligible to participate were enrolled full-time at a private New England University. With approval from the university Institutional Review Board, electronic mail addresses were obtained. Students were contacted by electronic mail and given information about the survey. Those who wished to participate were directed to a URL address with informed consent information. Participants were entered into a prize drawing; ten prizes valuing $25–$100 were distributed. Forty-percent of eligible (n =
Sample characteristics
Sample characteristics are presented in Table 1. The majority (78%) of respondents were white, non-Hispanic. The majority had previously heard of HPV and the vaccine (93% and 87%, respectively), though some misperceptions about the virus were prevalent (Table 2). In terms of stage of adoption, 13% had never heard of the vaccine (pre-contemplation), 15% were undecided about vaccination, 45% planned to obtain the vaccine after 30 days (contemplation), 8% planned to obtain vaccine within 30 days
Discussion
In the six to eight months following FDA approval of the HPV vaccine, we found that overall awareness of HPV and of the vaccine was high among this sample of college women, although knowledge about viral transmission, the role of Pap smears, and the lack of available treatment was low. Regardless, more than half (53%) reported they intended to obtain the vaccine at some time in the future, and 12% had already been vaccinated. However, about 15% of the women were undecided and 7% had already
Conclusions
The HPV vaccine will play a critical role in reducing the burden of HPV infection and cervical cancer, but only if there is widespread uptake. Successful public health efforts must address individual characteristics, socio-cultural influences and institutional factors that influence vaccination behaviors. This study contributes insights into the information needs of college-aged women and factors that may be particularly salient to the development of intervention messages for this population.
Conflict of interest statement
The authors declare that there are no conflicts of interest.
Acknowledgments
We gratefully acknowledge the contributions of the following individuals: Rose Felzani, Kristen Ferguson, Elizabeth Harden, Josh Jensen, Kerry Kokkinogenis, Sheila McMahon, Chad Minnich, Shannon Stock, and Amy Thompson. We thank all of the women who participated in this study, and who contributed their time and insights.
References (54)
- et al.
Acceptability to Latino parents of sexually transmitted infection vaccination
Ambul. Pediatr.
(2008) - et al.
Future acceptance of adolescent human papillomavirus vaccination: a survey of parental attitudes
Vaccine
(2006) - et al.
Predictors of HPV vaccine acceptability: a theory-informed, systematic review
Prev. Med.
(2007) - et al.
Women's attitudes on human papillomavirus vaccination to their daughters
J. Adolesc. Health
(2007) - et al.
Acceptance of human papillomavirus vaccination among Californian parents of daughters: a representative statewide analysis
J. Adolesc. Health
(2007) - et al.
Attitudes of mothers in Da Nang, Vietnam toward a human papillomavirus vaccine
J. Adolesc. Health
(2007) - et al.
Awareness, knowledge, and beliefs about human papillomavirus in a racially diverse sample of young adults
J. Adolesc. Health
(2008) - et al.
Knowledge about infection with human papillomavirus: a systematic review
Prev. Med.
(2008) - et al.
Parental acceptance of human papillomavirus vaccines
Eur. J. Obstet. Gynecol. Reprod. Biol.
(2008) - et al.
Parental attitudes to pre-pubertal HPV vaccination
Vaccine
(2007)