Several years after introduction of the HPV vaccine, in this study of female college students who had not yet initiated HPV vaccination and who sought routine gynecological care from a university health service at a large, public Michigan university, only 41% reported an intention to undergo HPV vaccination in the future. In Michigan, where rates of cervical cancer in situ (an immediate precursor to invasive cervical cancer) have been increasing since 1985 among women under 40 years of age (26
), interventions to promote HPV vaccine uptake will play an important role in cervical cancer prevention. In our study, the sizeable proportions of participants who reported they did not intend to undergo vaccination (31.3%) or were undecided (26.2%) highlight target populations for intervention. Our findings are strikingly consistent with a study conducted among female college students at the University of Kentucky prior to HPV vaccine licensure, in which 45.3% of participants reported that they were likely to be vaccinated against HPV within the next 12 months, 26% were unlikely to get vaccinated, and 28.5% were unsure (19
). In contrast, a study conducted by Boehner et al. in a similar sample size (n=256) of Midwestern undergraduate students found that 74% of male and female college students endorsed acceptance of a hypothetical vaccine against HPV (22
). Other studies conducted in college populations after introduction of the HPV vaccine into clinical practice have also shown higher acceptability of HPV vaccination, ranging from 53% (20
) to 65% (21
). These studies were conducted relatively soon after Gardasil® became clinically available, and it is possible that the initial phase of high acceptability was related to the intensive marketing surrounding the vaccine. Our study measures more recent levels of acceptance which are likely influenced by a variety of intervening information sources including the media, scientific literature, and reports of adverse events.
The intervention evaluated in this study, which combined basic HPV information and a simple mailed reminder, was not found to be associated with HPV vaccine uptake in this population. Only 6% of the study population received at least one dose of HPV vaccine within six months of enrollment, and this did not differ significantly between the intervention and standard care groups. We hypothesize several possible explanations for our findings. As nearly a year of clinical availability of HPV vaccine had passed even for the earliest enrolled study participants, this population may represent women who face more barriers or are more resistant to undergoing HPV vaccination. The educational fact sheet was modeled after fact sheets available from the CDC and was not specifically geared toward college females. Future investigation of the effectiveness of individually tailored interventions, which first assess the participant’s knowledge, perceptions and intentions and then incorporate this information into the intervention materials delivered, as a means of increasing HPV vaccine uptake in this population should be considered. Further, finding ways to implement these interventions via technologies acceptable to college students (e.g., text messaging, email, social networking media, etc.) could improve the efficacy of interventions aimed at this population.
Identifying and reducing barriers among individuals who intend to undergo HPV vaccination may be the most accessible opportunity to increase vaccination uptake. While only 14 participants received at least one dose of HPV vaccine within six months of study enrollment, the finding that uptake was significantly higher among those who intended to undergo HPV vaccination at baseline supports the importance of intention in the process of HPV vaccine uptake (24
). Further, we found that selected personal beliefs were significantly associated with intent to undergo HPV vaccination in this population, and that sociodemographic characteristics and sexual and medical history generally did not predict this intention. Boehner et al. identified higher number of lifetime sex partners, perceived parental perceptions about the vaccine, universal vaccine endorsement, low cost, and vaccine safety as significant predictors of acceptance of a hypothetical vaccine against HPV among Midwestern undergraduate students (22
). In a survey of racially diverse students from two southeastern universities, Gerend and Magloire (21
) found higher HPV vaccine interest among those women who were sexually active, had multiple sex partners, and perceived themselves to be vulnerable to HPV infection. In our study, perceived parental approval, perceived vulnerability to genital HPV infection, and belief that HPV vaccine is important for maintaining health were also significantly associated with HPV vaccine intent; however, a similar association with high lifetime number of sex partners was not observed. Most (74%) of our study population was currently sexually active; the lack of variability in sexual activity may, in part, explain the absence of findings between certain sexual history variables and intent to undergo HPV vaccination. Over three-fourths (78%) of study participants correctly answered at least four out of six HPV-related knowledge questions; however, the high level of HPV-related knowledge was not associated with intent to undergo HPV vaccination in this population. While the effectiveness of educational interventions on HPV vaccine acceptability has not been evaluated in the college population, findings from studies conducted among parents have been inconsistent. In a randomized intervention study conducted by Dempsey et al., the increased knowledge gained through written information about HPV did not translate to increased HPV vaccine acceptability among parents of preadolescent children (27
). In contrast, Davis et al. found that, among parents of 10- to 15-year-old adolescents who were initially opposed to or undecided about the HPV vaccine, 37% and 65%, respectively, supported HPV vaccination for their children after a brief educational intervention (28
). One of the few studies to assess HPV-related knowledge in university students generally did not find significant differences in vaccination status by HPV-related knowledge (29
). The collective findings suggest that factors beyond HPV knowledge, such as personal beliefs, attitudes and life experiences, may influence HPV vaccine acceptability and should be addressed in the development of interventions.
Practical barriers to HPV vaccination may be particularly difficult to surmount in the college population, perhaps more pronounced due to a lack of established standards of preventive care for this age group. Individuals in their teens and early 20s make fewer visits to physicians’ offices than at any other times in their lives and the majority fail to receive all recommended vaccines (30
). At the institution where this study was conducted, the health service fee paid as part of tuition covers basic services at the university-based health service but does not include vaccinations. Indeed, the high costs associated with the three-dose HPV vaccine series was identified as a barrier by 41.3% of our study population. Nearly two-thirds (62.1%) of study participants reported having supplemental insurance coverage, such as parental health insurance. This appeared to be an important factor in HPV vaccination intention as those who lacked health insurance beyond services covered by the student health fee were significantly less likely to intend to undergo HPV vaccination compared to those who had supplemental insurance [OR: 0.42 (95% CI: 0.22–0.80)]. It should be noted that the additional health insurance plan available to students for purchase through Aetna (included in the category of supplemental health insurance in this study) currently does not cover HPV vaccination, which complicates interpretation of this finding. As health care reform moves forward, changes in insurance coverage for routinely recommended vaccines could reduce cost as a barrier to HPV vaccination for young adult women. However, even with supplemental insurance, charges for services not covered by the health service fee may appear on parental insurance statements, potentially posing an additional barrier to HPV vaccine uptake for students concerned about parental notification of a vaccine against a STI. Still, a recent study by Conroy et al. identified coverage of the cost of HPV vaccination as the strongest predictor of actual HPV vaccine uptake among 13–26 year old females recruited from an urban, hospital-based adolescent primary care clinic (32
). Other hypothesized barriers to HPV vaccination, such as inconvenience of the 3-dose vaccine series, uncertainty of remaining in the same geographic location throughout the vaccine series, and general dislike of injections, were reported by fewer than 14% of participants. Instead, participants’ foremost concerns centered on vaccine safety (48.8%), side effects (48.8%), and long term consequences (40.0%).
In contrast to a study of college students from two southeastern universities that found greater HPV vaccine interest among sexually active women (21
), females in our study who were currently sexually active were significantly less likely to intend to undergo HPV vaccination compared to those who were not currently sexually active. A possible explanation is the perception that HPV vaccination is less effective (or even ineffective) after exposure to or infection with the virus. Indeed, of the 21 respondents who indicated “other” reason for not intending to undergo HPV vaccination, four (19.1%) specified that it was “too late” for them (due to previous HPV infection or number of sex partners). However, women already infected with a targeted HPV type still benefit from HPV vaccination because they are protected from infections and disease caused by HPV types for which they are naïve at the start of vaccination (33
), and very few women appear to have been previously infected with all four HPV vaccine types covered by Gardasil® (34
). With the accumulating data on prophylactic efficacy and safety comes a need to understand and address evolving perceptions and concerns surrounding HPV vaccination. Strikingly, nearly 29% of participants not intending to undergo HPV vaccination felt they were not at risk for STIs or genital warts. Moreover, of the 21 respondents who indicated “other” reason for not intending to undergo HPV vaccination, six (28.6%) specified they were in a monogamous sexual partnership. While only a small proportion (2.3%) of the study population had multiple sex partners, other risk factors for STI were prevalent including low condom use among those who were currently sexually active (24.1%) and greater than five lifetime sex partners (20.6%). These data highlight educational opportunities focusing on social and behavioral aspects of STI epidemiology (e.g., population-based estimates of new and lifetime sex partners) (35
), as well as the high rates of genital HPV acquisition in young men (18
) and women (17
). Messages aimed at currently sexually active women that specifically address misconceptions about the value of vaccination after coitarche (e.g., it is not “too late” and the vaccine may protect against strains to which they have not been exposed) could be a valuable component of education-based and other public health interventions to improve HPV vaccine uptake. From a research perspective, gaining a better understanding of self-perceived STI risk in this population may inform the development of strategies to increase awareness and, ultimately, uptake of protective behaviors.
Several limitations of this study should be considered. Because we focused on females seeking routine health maintenance at a university health service, the study population may not reflect the overall population of college-age women at our institution, women of the same age range in other university settings, or women of the same age range who do not attend college. Within the clinic, however, study participants were similar to those who refused participation on basic sociodemographic characteristics. The small number of participants (n=14) who received at least one dose of HPV vaccine within six months of study enrollment limited our ability to identify independent predictors of vaccine uptake or further subgroup analyses. It would have been useful to identify participants for whom HPV vaccination was a covered benefit, however, we did not collect detailed information on type of health insurance among those who reported having some type of supplemental health insurance. Completeness of HPV vaccination data remains a challenge in the college setting. Given that the vaccine series is administered in three doses over a six-month period, college students may receive some doses outside the UHS setting (for example, physician in home town). Further, as the cost of the vaccine series could be prohibitive, college students may seek alternative sites (for example, health department) for lower cost vaccine. In our study, vaccines received outside the UHS system were not reliably captured in the medical record. While we attempted to enhance completeness of the uptake data through a combination of survey, telephone and email follow-up, vaccination history based on self-report is subject to bias and is unknown for those we could not contact.
This study provides some insight on factors influencing HPV vaccine intent and uptake, among female students attending a university-based gynecology clinic at a large, public Midwestern university. In contrast to earlier studies that identified practical barriers and sexual history as predictors of HPV vaccine intent in college age populations, findings from this study conducted three years after introduction of the HPV vaccine suggest that personal beliefs play an important role. In light of the sizeable proportion of women indicating intention to undergo HPV vaccination, identification of barriers to behavioral follow-through specific to the college setting could help reduce missed opportunities for HPV prevention. Perceived risk of STI and its relationship to preventive behaviors, particularly among those in committed or long term relationships, also warrants further study among college-age individuals. Interventions to increase HPV vaccine intention and, ultimately, uptake in the college population should address personal HPV-related beliefs in addition to broader barriers to vaccination.