PERSISTENT INFECTION WITH HUMAN PAPILLOMAVIRUS (HPV) is a necessary cause of cervical cancer.1 Genital infection with low-risk HPV subtypes (HPV 6, 11) can cause genital warts, whereas infection with high-risk subtypes (most often HPV 16 and 18) can result in cervical intraepithelial neoplasia (CIN) and may eventually progress to cervical cancer.1,2 Although Pap testing has significantly reduced the incidence of cervical cancer in the United States,2 an estimated 4,000 U.S. women died of cervical cancer in 2005.3
Prophylactic HPV vaccines have been developed and will be available in the near future. Clinical trials suggest that they are safe and highly effective in preventing HPV infection and CIN.4–6 A quadrivalent vaccine (Gardasil manufactured by Merck) that protects against infection by HPV 6, 11, 16, and 18 was approved by the U.S. Food and Drug Administration in June 2006 for females ages 9 to 26. The Advisory Committee on Immunization Practices (ACIP) has since recommended routine HPV vaccination in 11- and 12-year-old girls, but noted that the HPV vaccine can be given to girls as young as age 9.7 Furthermore, the ACIP recommends that girls/women ages 13 to 26 receive HPV vaccination if they have not been previously vaccinated for HPV or have not completed the 3-dose HPV series.
The purpose of the current study was to examine underserved women's acceptability of the forthcoming HPV vaccines, both for themselves and their children, and to identify health beliefs and behaviors associated with vaccine acceptance. Although some have speculated that sexually transmitted infection (STI) vaccines will be met with reluctance because of the social stigma that often accompanies such infections,8 research is inconsistent with this view.9 In fact, data suggest that people are generally interested in STI vaccination for themselves10–14 and their children.15–19 Greater willingness to get vaccinated for HPV is typically seen among individuals who feel more vulnerable to HPV infection, associate vaccination with greater benefits and fewer barriers, hold positive attitudes toward vaccination, perceive the HPV vaccines to be safe and effective, and believe that other people—parents, healthcare providers—would encourage them to get vaccinated.8–11,19
Theory and previous research guided the selection of predictor variables. We drew on the Health Belief Model (HBM) and the Theory of Reasoned Action (TRA)—theories that have successfully predicted a wide range of health behaviors,20 including STI vaccination.10,12 Consistent with the HBM, we predicted that greater perceived benefits of HPV vaccination and greater perceptions of susceptibility to and severity of HPV infection would be associated with higher vaccine acceptability, whereas greater perceived barriers to HPV vaccination would be associated with lower acceptability. Consistent with the TRA, we predicted that positive attitudes and normative beliefs favoring HPV vaccination would be related to higher acceptance rates. Based on previous research,10,11,13,18 greater vaccination intentions were expected to be associated with more lifetime sexual partners and previous engagement in health protective behaviors (e.g., Pap testing, HIV testing).
Research suggests that knowledge of HPV and its relationship to cervical cancer is relatively low in the general population.21,22 Thus, before assessing participants' interest in obtaining the HPV vaccine, we provided each participant with detailed information about HPV, the relationship between HPV and cervical cancer, and the potential role of the new vaccines in preventing infection by HPV and, ultimately, cervical cancer.
Participants (n = 58) were recruited from 3 community clinics providing health care to underserved populations in North Florida: Tallahassee Memorial Family Practice Residency Program (n = 36), Jefferson County Health Department (n = 11), and Leon County Health Department (n = 11). Approximately two thirds of the sample was age 26 or younger. See Table 1 for sociodemographic characteristics. Recruitment signs instructed women ages 18 to 50 years to approach the interviewer in the waiting room if they were interested in participating in a women's health study. Data were collected during July, October, and November 2005. Participants were paid $10 for completing the 20- to 25-minute interview.
The semistructured interview was divided into 3 phases: 1) preeducation interview, 2) patient education session, and 3) posteducation interview. The preeducation interview assessed sociodemographic information, sexual history, and other health-related behaviors (see Table 1). We also assessed perceived susceptibility to HPV infection and cervical cancer (1 = not at all likely to 6 = very likely) and perceived severity of HPV infection (“Having genital HPV would be upsetting to me”; “Having genital HPV would make it difficult for me to get a long-term sexual partner”; 1 = strongly disagree to 6 = strongly agree).
During the patient education phase, participants were given standardized information about HPV infection (definition, prevalence, transmission methods, signs and symptoms, complications, treatments), cervical cancer, Pap testing, and the forthcoming HPV vaccines. The posteducation interview assessed health beliefs, HPV vaccination attitudes, and intentions to get vaccinated for HPV. Health beliefs and attitudes toward HPV vaccination were assessed on a 6-point scale (1 = disagree strongly to 6 = agree strongly) and included perceived safety, effectiveness, and benefits of the HPV vaccine; perceived barriers to receiving the HPV vaccine (getting the HPV vaccine could be risky, having to get shots, if health insurance will not cover the vaccine); and normative beliefs about the vaccine (perceived physician encouragement for HPV vaccination).
Personal HPV vaccine acceptability was assessed with 4 items: How likely is it that you will: 1) try to get more information about, 2) consider getting, and 3) actually get the HPV vaccine once it is available? Participants also rated 4) the likelihood they will get the HPV vaccine if a healthcare provider offers it to them in the next 3 years (1 = very unlikely to 6 = very likely). The 4 items were averaged to create a composite (α = 0.90). Parents (n = 42; mean age = 28 years, standard deviation [SD] = 9.1) indicated whether they were interested in having their child/children vaccinated for HPV (yes/no).
Personal intentions to get vaccinated for HPV were generally high (mean = 5.40, SD = 0.96). Seventy-six percent had a score of 5 or higher on the composite measure of vaccine acceptability. One hundred percent of parents indicated that they would be interested in having their child/children vaccinated for HPV. Lack of variability on this measure prevented us from examining correlates of parental acceptance.
Correlations between HPV vaccine acceptability and sociodemographic variables, health beliefs, and behavior are given in the first column of Table 2. Correlates of HPV vaccination intentions included perceived susceptibility to HPV, perceived safety of the HPV vaccine, perceived effectiveness of the HPV vaccine (“The vaccine will protect people from getting HPV”), perceived physician encouragement for HPV vaccination, and HIV testing history.
Variables correlated with HPV vaccination intentions at P <0.05 or better were entered into a multiple regression analysis predicting vaccine acceptability (Table 2, second column). Independent predictors of vaccine acceptability included perceived safety of the HPV vaccine, perceived supportiveness of one's doctor for getting vaccinated, and having been tested for HIV. These variables accounted for 61% of the variance in HPV vaccination intentions (F [5,45] = 14.169, P <0.001).
The current study sheds light on underserved women's interest in receiving the forthcoming HPV vaccines. Over three fourths of those interviewed endorsed strong intentions to obtain HPV vaccination. Moreover, 100% of parents were interested in having their child or children vaccinated. These findings run counter to speculations that HPV vaccines will be met with strong opposition because they are intended to prevent an STI. Rather, they provide additional evidence to an emerging body of literature indicating widespread and relatively enthusiastic support for HPV vaccination.
Correlates of vaccine acceptability identified in the present sample of underserved women were consistent with studies conducted in other populations.8,10–13 Results from this study point to the importance of health beliefs and prior behavior in motivating future health-protective actions such as STI vaccination. Women who felt more susceptible to HPV infection reported greater vaccination intentions. Furthermore, greater confidence in the safety and efficacy of the HPV vaccines was associated with higher vaccine acceptability. The strongest correlate of vaccine acceptance was holding the belief that one's physician will encourage HPV vaccination. Three independent predictors of vaccine acceptability were identified: perceived safety of the HPV vaccine, perceived encouragement from one's physician to get vaccinated, and having received an HIV test. That previous HIV testing was associated with greater interest in the HPV vaccine may reflect a general tendency to engage in health-protective behaviors and/or perceptions of risk to STIs more generally.
Given evidence that public knowledge of HPV is quite low,21,22 it is likely that the patient education session of the current study had an important effect on our findings. Studies examining the use of patient education materials for encouraging HPV vaccine acceptance have reported differential success.15,16,23 Nevertheless, to promote widespread acceptance of the HPV vaccine, it will be important for healthcare providers to give patients/parents (at a minimum) basic information about HPV before offering the vaccine.24
Limitations of the current study provide important opportunities for future research. The primary limitation was the small sample size. In addition, lack of variability in parental interest in HPV vaccination limited our ability to examine correlates of parental acceptance. Furthermore, because we did not assess children's ages, we cannot make specific claims about the role of child age in relation to parental acceptance of the HPV vaccines.
HPV vaccination could have an enormous impact on the health and well-being of women worldwide. In addition to reductions in morbidity and mortality from cervical cancer and HPV-related disease, the HPV vaccines may also reduce psychologic distress that often accompanies an abnormal Pap test or diagnosis of genital warts.25 Yet these benefits will only be achieved through widespread acceptance of the vaccines. The current study highlights key correlates of vaccine acceptability that may inform future HPV vaccination campaigns. Our findings suggest that increasing awareness of HPV infection and its clinical sequelae as well as publicizing the safety and efficacy of the HPV vaccines should yield the greatest acceptance. Endorsement of the HPV vaccines from healthcare providers is also likely to result in increased willingness to accept HPV vaccination.
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