Support for HPV Vaccination Mandates for Both Females and Males Matthew Lee Smith, PhD, MPH, CHES; Kelly L. Wilson, PhD, MCHES; Jairus C. Pulczinski; Marcia G. Ory, PhD, MPH Objectives: To examine college students’ support for HPV vaccination mandates for school-aged youth and examine perceptions and behavioral factors associated with vaccine mandate support for both boys and girls. Methods: Data were collected from 1322 college students by an Internet-delivered questionnaire. Bivariate analyses and logistic regression were performed. Results: Relative to those who did not support HPV vaccination mandates for school-aged boys and girls, females (p = .038), non-white par-
H
uman papillomavirus (HPV) is one of the most common sexually transmitted infections (STI) and has been identified as the leading cause of cervical cancer in the United States.1 In 2008, approximately 14 million Americans were estimated to be newly infected with HPV, over half of whom were youth between the ages of 15 to 24 years.2 Whereas the average age of first sexual intercourse in America is around age 17 years,3 engagement in sexual behaviors with direct skin-to-skin contact (including heavy petting and oral sex) may occur years before sexual intercourse and are known risk behaviors for HPV transmission.4 To date, the Food and Drug Administration has approved 2 vaccines (ie, Gardasil and Cervarix) to protect females and males against particularly virulent HPV strains. Both vaccines target HPV types 16 and 18 that are responsible for 70% of cervical cancers;5 moreover, Gardasil also protects against HPV types 6 and 11 that are responMatthew Lee Smith, Assistant Professor, Department of Health Promotion and Behavior, College of Public Health, University of Georgia, Athens, GA. Kelly L. Wilson, Associate Professor, Department of Health and Kinesiology, Texas A&M University, College Station, TX. Jairus C. Pulczinski, Research Assistant, Department of Health Promotion and Community Health Sciences, School of Public Health, Texas A&M Health Science Center, College Station, TX. Marcia G. Ory, Regents Professor, Department of Health Promotion and Community Health Sciences, School of Public Health, Texas A&M Health Science Center, College Station, TX. Correspondence Dr Smith; [email protected]
Am J Health Behav.™ 2014;38(6):831-838
ticipants (p = .001), those who generally supported HPV vaccination mandates (p < .01), and those who had had sexual intercourse (p = .005) were significantly more likely to support HPV mandates for both sexes. Conclusions: Identifying those who support HPV vaccination mandates is important for increasing vaccine uptake and reducing HPV-related cancers. Key words: human papilloma virus, vaccination, policy, mandate Am J Health Behav. 2014;38(6):831-838 DOI: http://dx.doi.org/10.5993/AJHB.38.6.5
sible for 90% of genital wart cases.6 Gardasil is approved for use among females and males between the ages of 9 and 26 years to protect females against cervical cancer and both sexes against genital warts.7 The Advisory Committee on Immunization Practices (ACIP) recommends routine initial HPV vaccination at age 11 or 12 years for girls, with additional vaccination cycles between the ages of 13 and 26 years.8 The ACIP recommends routine vaccination of males aged 11 and 12 years and vaccination for males aged 13 to 21 years who have not been vaccinated previously or received a full 3-dose regimen.8,9 Despite national vaccination recommendations (eg, from the President’s Cancer Panel) and guidelines as well as few known risks associated with the HPV vaccine,6 uptake rates are modest compared to other vaccinations recommended for adolescents.10,11 From 2007 to 2011, an increase in HPV vaccination coverage was observed among adolescent females; however, no change was seen in 2012.6 Approximately 53.8% of adolescent females had initiated the 3-dose HPV vaccination series, but only about 33% received all 3 recommended doses.12 HPV vaccine uptake among males remains exceedingly low relative to females.11 To increase HPV vaccination uptake rates among adolescents, efforts have been employed to understand obstacles to vaccination uptake. Identified factors contributing to HPV vaccination include perceiving the vaccine as safe, perceiving personal risk for contracting HPV, receiving a physician rec-
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Support for HPV Vaccination Mandates for Both Females and Males ommendation, and believing vaccination would not promote sexual activity among youth.13 These issues are complicated further by ethical concerns among members of the medical community and moral opposition from certain subgroups.14-16 The most influential strategy to increase vaccine uptake is to pass laws that mandate vaccination behavior;10 however, such regulations cannot pass without fostering vaccination acceptability and public support. Vaccine mandates can protect large numbers of individuals against HPV and associated cancers, which can directly reduce infection rates through herd immunity. Such effects have potential to reduce health inequalities caused by HPV. Despite potential public health benefits, HPV vaccination mandates were proposed and advocated for prior to establishing widespread support for the HPV vaccine. More specifically, before the broad public and authoritative agencies agreed upon vaccine recommendations, HPV mandate proposals were put forth.15 These actions may have resulted in damaging effects for HPV mandates and calls for coordinated approaches that simultaneously release vaccines into the market along with strict recommendations for use and mandates. Despite current resistance to HPV vaccine mandates for school attendance, the issue likely will be revisited as an important component of adolescent healthcare,17 especially as vaccination recommendations for males increase. Although the HPV vaccine is approved for males aged 9 to 26 years, the vaccine was originally recommended for use among females and marked as a preventive measure against cervical cancer. Even though the vaccine protects against anogential cancers for either sex, the disproportionate burden of these cancers on the female population marks them as the more appropriate target for the vaccination and associated mandates.6 Whereas anogential cancer mortality is lower among males, they serve as a reservoir for the virus and contribute to the spread of HPV in the female population.17 This fact, combined with their risk for HPV-related cancers and genital warts, makes males appropriate targets for the vaccine and associated mandates. Therefore, the following question arises: if new HPV vaccination mandates surface for school-aged youth, should mandates target both sexes? Utilizing a sample of young adults aged 18 to 26 years, the purposes of this exploratory study were to: (1) describe personal characteristics, health behaviors, normative beliefs, and HPV-related knowledge of young adults based on their support for HPV vaccine mandates for school-aged girls and boys; and (2) assess factors associated with support for HPV vaccine mandates for both sexes. College-aged individuals were selected because they comprise a unique audience that is transitioning into adulthood and that recently has become able to make healthcare decisions without parental consent. In many cases, these individuals will
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become parents in forthcoming years, thereby requiring them to make health-related decisions for themselves and their children. Additionally, these individuals represent a subset of potential voters who are eligible to impact healthcare issues. METHODS Participants and Procedures Data were collected from a sample of young adults enrolled in 2 large Texas universities using an Internet-delivered survey instrument hosted by Qualtrics. Participants were recruited at each institution via electronic mail (e-mail). Researchers disseminated e-mail messages to every enrolled student using university-regulated delivery systems (ie, a university service provided to investigators for the purposes of sending mass e-mails to students for research recruitment). Recruitment email text provided participants with the URL address for the Internet-based survey. After sending initial recruitment emails, a reminder email was distributed 5 days later. Data were collected over a 2-week period at each institution. Participation in this study was voluntary, no identifying information was collected from participants, and no incentives were provided to respondents for participating in the study. Of the 81,715 enrolled students who received the email (ie, total student enrollment of 49,129 and 32,586 at each institution, respectively), 3987 students responded to the survey (response rate = 4.9%) with 2513 participants completing the instrument (completion rate = 63.1%). Although participants both responding to and completing the instrument were representative of the student populations at these 2 universities in terms of age and race/ethnicity; the study sample had disproportionately more females (81% versus 47% and 56%, respectively). Participants who were over the age of 26 years (N = 469) were omitted from analyses based on specified study aims. To alleviate biased responses, participants who were married (N = 307), diagnosed with cervical cancer (N = 29), told they had HPV (N = 438) or genital warts (N = 153), or had an immediate family member with cervical cancer (N = 345) were removed from the study. Additionally, participants who reported they supported HPV vaccine mandates for only girls (N = 165) or only boys (N = 33) were omitted from analyses because cell sizes were inadequate for comparative purposes. Some participants cited more than one of these exclusionary responses so the usable final sample was 1322 young adults. Instrument Participants were surveyed using a questionnaire consisting of 76 multi-part items, which included skip patterns used to advance participants through the instrument based on provided responses. The instrument was comprised of a combination of Likert-type scales, closed-ended response items, and
Smith et al open-ended response items. The instrument used items previously tested and validated by other researchers.18,19 The authors also added items to assess participants’ perceptions about HPV vaccine mandates, facilitators and barriers of receiving HPV vaccinations, and health-related behaviors, among other items. Participants took approximately 15 minutes to complete the survey. Measures Dependent variable. The dependent variable for this study was participants’ support for HPV vaccination mandates for school-aged youth. Participants were asked: “If there was a HPV vaccine approved for both school-aged males and females, who do you think should be mandated to get the vaccine?” Possible response categories included “neither males nor females,” “males only,” “females only,” and “both males and females.” Based on the purposes of this study and the cell sizes for response choices, this variable was dichotomized. The response choices “males only” (N = 33) and “females only” (N = 165) were omitted. The recoded variable used in analyses contained the response choices “neither males nor females” and “both males and females.” Not supporting HPV vaccination mandates for either sex served as the referent group for logistic regression. HPV vaccine perceptions. Participants were asked: “In your opinion, would getting the HPV vaccine make it safer to have more sexual partners?” Response categories included “no” and “yes.” HPV-related knowledge. Participants were asked to complete 11 items intended to measure the extent to which they were knowledgeable about HPV.18 Respondents were asked to indicate which of the statements were true or false. For example, participants were asked to rate statements like: “A person may be infected and not know it,” “Pap smears can detect HPV,” “HPV can be cured with antibiotics,” and “Certain types of HPV cause cancer.” Response categories included “true,” “false,” and “I don’t know.” Items endorsed correctly were coded as “1,” and those endorsed incorrectly were coded as “0.” The HPV-related knowledge score ranged from 0 to 11 for this count variable. Number of friends vaccinated. Participants were asked to report the number of their friends who had already received the HPV vaccination.18 Response categories included “none,” “some,” “most or all,” and “I don’t know.” HPV vaccine mandate support by age group. Participants were asked to report their general support for individuals within specified age groups. Respondents were provided with the following definition and question: “A mandate is something that is required by law. Do you think the HPV vaccine should be mandated (eg, required by law) for those….?” Age groups provided to participants were “between the ages of 9 and 11,” “between the ages of 12 and 17,” and “between the ages of 18 and 26.” Participants responded to each age group
Am J Health Behav.™ 2014;38(6):831-838
separately. Response categories included “no” and “yes.” Sociodemographics. Personal characteristics of the participants included age (ie, 18 to 26 years), sex, race/ethnicity (ie, non-Hispanic white, nonwhite), and insurance status (ie, insured, uninsured). Statistical Analyses All statistical analyses were performed using SPSS (version 22). Frequencies were calculated for all major study variables, which were initially examined in relationship to respondents’ sex and reported support for HPV vaccination mandates for both sexes. Pearson’s chi-square tests were performed to assess the independence between dependent variable and categorized independent variables. Independent sample t-tests were used to examine mean differences for continuous variables. Three logistic regression models were fitted to examine factors associated with HPV vaccination mandate support for both sexes (ie, not supporting HPV vaccination mandates for either sex served as the referent group). One regression model was fitted using all study participant data. Then, one model was fitted using only male participant data and one model using only female participant data. Odds ratios, and 95% confidence intervals, and model fit statistics are reported for each regression model. RESULTS Sample Characteristics of study participants are presented in Table 1. Of the 1322 participants, 81.0% were female and 19.0% were male. Over 42% did not support HPV vaccination mandates for either school-aged girls or boys, and 57.8% supported HPV vaccination mandates for both sexes. The average age was 20.95 years (±1.96). Approximately 76% of participants were non-Hispanic Whites, and 67.5% reported having engaged in sexual intercourse. Most of the participants had health insurance (91.7%). On average, participants had HPV-related knowledge scores of 7.93 (±1.89) out of 11 possible points. Approximately 40% of participants reported some of their friends had received the HPV vaccine, and 10.2% reported most or all of their friends had received the HPV vaccine. When asked about general support of HPV vaccination mandates, 15.1% supported mandates for individuals between the ages of 9 and 11 years, 48.4% for individuals between the ages of 12 and 17 years, and 48.9% for individuals between the ages of 18 to 26 years. Over 27% of participants reported that getting the HPV vaccine would make it safer to have more sexual partners. Significant differences were observed when comparing sample characteristics by sex. On average, females were significantly younger (t = 5.28, p < .001) and had higher HPV-related knowledge scores (t = -5.89, p < .001) than their male counterparts.
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Support for HPV Vaccination Mandates for Both Females and Males
Table 1 Sample Characteristics by Sex and HPV Vaccine Mandate Support for Both Sexes Total (N = 1322)
Sex
Men (N = 448)
Women (N = 586)
χ2 or t
p
Neither Boys Nor Girls (N = 558)
Both Boys and Girls (N = 764)
χ2 or t
p
--
--
2.04
0.153
Male
19.0%
--
--
20.8%
17.7%
Female
81.0%
--
--
79.2%
82.3%
Age (18 to 26)
20.95 (±1.96)
21.58 (±2.17)
20.80 (±1.88)
5.28
< .001
20.83 (±1.89)
21.03 (±2.01)
-1.87
.062
Race/ethnicity
1.18
.278
21.16
< .001
Non-Hispanic white
76.3%
73.7%
76.9%
82.6%
71.7%
Non-white
23.7%
26.3%
23.1%
17.4%
28.3%
Insurance status
1.09
.296
0.48
.489
Uninsured
8.3%
10.0%
7.9%
7.7%
8.8%
Insured
91.7%
90.0%
92.1%
92.3%
91.2%
3.48
.062
47.47
< .001
32.5%
27.5%
33.6%
42.8%
24.9%
Ever had sexual intercourse No Yes HPV-related knowledge (0 to 11) Proportion of friends who received HPV vaccine
67.5%
72.5%
66.4%
57.2%
75.1%
7.93 (±1.89)
7.19 (±2.30)
8.10 (±1.74)
-5.89
< .001
7.87 (±1.88)
7.97 (±1.90)
-1.01
.312
93.70
< .001
52.04
< .001
None
12.0%
14.7%
11.4%
16.7%
8.6%
Some
40.2%
21.1%
44.7%
42.7%
38.5%
Most/All
10.2%
2.8%
12.0%
4.3%
14.5%
Don’t Know
37.5%
61.4%
31.9%
36.4%
38.4%
3.85
.050
123.18
< .001
No
84.9%
80.9%
85.8%
97.7%
75.5%
Yes
15.1%
19.1%
14.2%
2.3%
24.5%
0.24
.622
607.19
< .001
No
51.6%
53.0%
51.3%
91.2%
22.6%
Yes
48.4%
47.0%
48.7%
8.8%
77.4%
0.92
.337
623.17
< .001
No
51.1%
53.8%
50.4%
91.2%
21.7%
Yes
48.9%
46.2%
49.6%
8.8%
78.3%
15.34
< .001
11.03
.001
No
72.8%
62.9%
75.2%
77.6%
69.4%
Yes
27.2%
37.1%
24.8%
22.4%
30.6%
Support HPV vaccine mandates: ages 9 to 11
Support HPV vaccine mandates: ages 12 to 17
Support HPV vaccine mandates: ages 18 to 26
Getting HPV vaccine means can have more sex partners
A significantly larger proportion of females reported having larger proportions of friends who had received the HPV vaccine and a larger proportion of males reported not knowing their friends’ vaccination status (χ2 = 93.70, p < .001). Furthermore, a significantly larger proportion of males reported that getting the HPV vaccine would make it safer to have more sexual partners (χ2 = 15, p < .001). Significant differences were observed when comparing sample characteristics by whether or not participants supported HPV vaccination mandates for school-aged youth. A significantly larger proportion of participants supporting HPV vaccination mandates for both sexes were non-white (χ2 = 21.16, p < .001) and engaged in sexual intercourse (χ2 = 47.47, p < .001). A significantly larger proportion of participants supporting HPV vaccination man-
834
dates for both sexes reported having larger proportions of friends who had received the HPV vaccine (χ2 = 52.04, p < .001). Furthermore, a significantly larger proportion of participants supporting HPV vaccination mandates for both sexes reported generally supporting HPV vaccination mandates for individuals between the ages of 9 and 11 years (χ2 = 123.18, p < .001), 12 and 17 years (χ2 = 607.19, p < .001), and 18 and 26 years (χ2 = 623.17, p < .001). A significantly larger proportion of participants supporting HPV vaccination mandates for both sexes reported that getting the HPV vaccine would make it safer to have more sexual partners (χ2 = 11.03, p < .001). Table 2 displays the results of logistic regression analyses explaining factors associated with participants supporting HPV vaccination mandates
Smith et al
Table 2 Factors Associated with Believing Boys and Girls Should Be Mandated to Receive the HPV Vaccine
Model 1
Model 2
Model 3
All Participants (N = 1322)
Men Only (N = 251)
Women Only (N = 1071)
95% CI
95% CI
95% CI
OR
p
Lower
Upper
OR
p
Lower
Upper
OR
p
Lower
Upper
Age
1.09
.065
1.00
1.19
1.38
.007
1.09
1.74
1.04
.480
0.94
1.15
Male
1.00
--
--
--
--
--
--
--
--
--
--
--
Female
1.63
.038
1.03
2.60
--
--
--
--
--
--
--
--
Non-Hispanic white
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Non-white
2.00
.001
1.34
2.99
4.46
.003
1.67
11.89
1.63
.032
1.04
2.54
Uninsured
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Insured
1.50
.205
0.80
2.81
6.65
.022
1.31
33.82
1.21
.595
0.60
2.41
Never had sexual intercourse
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Had sexual intercourse
1.71
.005
1.18
2.47
2.05
.190
0.70
6.00
1.73
.008
1.16
2.58
HPV-related knowledge
1.00
.969
0.91
1.10
0.98
.867
0.81
1.20
1.01
.911
0.90
1.12
Some friends received HPV vaccine
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
No friends received HPV vaccine
0.70
.072
0.47
1.03
1.04
.948
0.34
3.16
0.63
.035
0.41
0.97
Most/all friends received HPV vaccine
0.80
.413
0.47
1.36
1.27
.707
0.37
4.39
0.64
.148
0.35
1.17
Don’t know number of friends received HPV vaccine
0.96
.901
0.47
1.95
2.55
.612
0.07
95.87
0.85
.669
0.41
1.78
Not support HPV vaccine mandate: ages 9 to 11
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Support HPV vaccine mandate: ages 9 to 11
2.59
.009
1.27
5.26
1.93
.414
0.40
9.39
2.89
.011
1.27
6.56
Not support HPV vaccine mandate: ages 12 to 17
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Support HPV vaccine mandate: ages 12 to 17
8.49
< .001
5.51
13.07
12.59
< .001
3.50
45.31
8.22
< .001
5.16
13.08
Not support HPV vaccine mandate: ages 18 to 26
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Support HPV vaccine mandate: ages 18 to 26
10.93
< .001
7.32
16.32
16.20
< .001
5.36
49.00
10.24
< .001
6.62
15.84
Getting HPV vaccine means can have more sex partners: No
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Getting HPV vaccine means can have more sex partners: Yes
1.13
.544
0.76
1.66
1.24
.673
0.46
3.30
1.17
.473
0.76
1.81
Nagelkerke R square = 0.658
Nagelkerke R square = 0.746
Nagelkerke R square = 0.643
Note. Referent Group: Believe males and females should NOT be mandated to receive the HPV vaccine
for school-aged girls and boys (ie, not supporting HPV vaccination mandates for either sex served as the referent group for all 3 models). In Model 1 using all participant data, females (OR = 1.63, p = .038), non-white participants (OR = 2.00, p = .004), and those who reported having sexual intercourse in their lifetime (OR = 1.71, p = .005) were significantly more likely to support HPV vaccination mandates for both sexes. Participants who reported supporting general HPV vaccine mandates for persons between the ages of 9 and 11 years (OR = 2.59, p = .009), 12 and 17 years (OR = 8.49, p < .001), and 18 and 26 years (OR = 10.93, p < .001) were significantly more likely to support HPV vaccination mandates for both sexes. In Model 2 using only male participant data, older participants (OR = 1.38, p = .007), non-white participants (OR = 4.46, p = .003), and those with health insurance (OR = 6.65, p = .022) were significantly more likely to support HPV vaccination mandates for both sexes. Males who reported sup-
porting general HPV vaccine mandates for persons between the ages of 12 and 17 years (OR = 12.59, p < .001) and 18 and 26 years (OR = 16.20, p < .001) were significantly more likely to support HPV vaccination mandates for both sexes. In Model 3 using only female participant data, non-white participants (OR = 1.63, p = .032) and those who reported having sexual intercourse in their lifetime (OR = 1.73, p = .008) were significantly more likely to support HPV vaccination mandates for both sexes. Females who reported none of their friends had received the HPV vaccine were significantly less likely to support HPV vaccination mandates for both sexes (OR = 0.63, p = .035). Participants who reported supporting general HPV vaccine mandates for persons between the ages of 9 and 11 years (OR = 2.89, p = .011), 12 and 17 years (OR = 8.22, p < .001), and 18 and 26 years (OR = 10.24, p < .001) were significantly more likely to support HPV vaccination mandates for both sexes.
Am J Health Behav.™ 2014;38(6):831-838
DOI:
http://dx.doi.org/10.5993/AJHB.38.6.5
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Support for HPV Vaccination Mandates for Both Females and Males DISCUSSION Human papillomavirus vaccination is a controversial topic that is often polarizing. The protective nature of the vaccine against several types of cancer has encouraged multiple states to attempt passing HPV vaccination mandates that require school-aged children to obtain the vaccine prior to enrollment.20 Many claim this would be an effective strategy to protect youth because similar institutional mandates have increased vaccination uptake and coverage.10, 21, 22 However, in part because HPV is sexually transmitted, HPV vaccination mandates have resulted in political, religious, and ethical opposition.15, 16 Alongside the ongoing controversy, HPV vaccination and associated mandate discussions have focused primarily on vaccinating young females because vaccine-marketing campaigns have largely surrounded cervical cancer prevention. However, the availability of approved HPV vaccinations for males has widened the potential market, yet uptake remains low.12 Because of recent proposals and votes to pass legislation about HPV vaccinations among school-aged youth in many states, the current study investigated factors associated with HPV vaccination mandate support for both males and females. Whereas a variety of reasons influence healthcare access and utilization among Americans,23 examining mandate support among the college-aged population is important because it has potential to influence grand-scale policies that uniformly protect school-aged youth. More specifically, collegeaged individuals are a critical population to study in the context of HPV vaccinations and mandates because: (1) this age group is a high-risk population for HPV and other STIs; (2) college has been identified a time for sexual initiation and exploration, which increases the risk for contracting HPV; and (3) this age group is considered to be a group of young voters, many who have just recently turned 18 years, are potentially future parents, and are now eligible to make their own health decisions as well as vote about important health policies. In this study, HPV vaccination mandate support was modest for individuals aged 9 to 11 years (15.1%) but increased to about 50% for individuals aged 12 to 26 years. Even among supporters of HPV vaccination mandates for both sexes, only 24.5% supported vaccinations for individuals aged 9 to 11years, compared to over 77% for the individuals aged 12 to 26 years. These findings highlight a general disconnect with FDA and ACIP HPV vaccination recommendations for those ages 9 to 11 years.8,9 The lack of mandate support for youth ages 9 to 11 years may stem from the belief these youth are not sexually active, are at low risk for HPV, and thus, should not be vaccinated. However, for the vaccine to be successful, it should be administered to those individuals before exposure to the virus. In addition, considering the average age of sexu-
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al debut is approximately 17 years in the United States24,25 (and that kissing, petting, and fellatio/ cunnilingus may occur prior to intercourse), this younger population should be considered an important demographic for vaccine mandate strategies. Over half of study participants (57.8%) supported HPV vaccination mandates for both sexes. Bivariate analyses revealed personal characteristics (ie, being non-white), behaviors (ie, being sexually active), and peer group characteristics (ie, having more friends vaccinated for HPV) were associated with supporting HPV vaccination mandates for both sexes. However, multivariate analyses revealed that sex, being sexually active, and general mandate support for ages 9 to 26 years were significantly related to mandate support for both sexes. These findings are interesting, yet not unexpected. Although it seems intuitive that participants who generally supported vaccination mandates would be more likely to support such mandates for both sexes, it is interesting that the rate of mandate support for both sexes exceeded general support rates for all age groups included in study analyses. This finding may indicate participants recognized the shared responsibility of males and females in HPV transmission and subsequent genital warts and cancers. Conversely, this finding may indicate that participants recognize the risk HPV introduces for warts and cancers among males. When comparing study findings by participant sex, females were significantly more likely to support mandates for both sexes. This may indicate females recognized the potential of mandates for both sexes to provide greater protection and that being vaccinated is a shared responsibility for both sexes. Conversely, lesser mandate support among males may indicate they still perceive HPV vaccination as a female-related health issue. Sex-based mandate support differences may also be explained by other study findings. The average HPV knowledge score for males was lower than for females, which may suggest males need more education about HPV and related modes of transmission/protection. Higher HPVrelated knowledge among females may be because they more regularly interact with healthcare providers during gynecological examinations.26,27 Additionally, females who reported having sex were more likely to support mandates for both sexes, which supports this finding in that sexually active females are recommended to receive regular Pap tests,28 This knowledge-related interpretation may be further supported by the finding that males who had insurance were significantly more likely to support mandates for both sexes. This association was not statistically significant among females. This finding may indicate that males with insurance interact with physicians more than their male counterparts without insurance, which could contribute to their HPV-related knowledge. Findings suggest that social influences also may
Smith et al impact mandate support. For example, study findings showed that female participants who reported none of their friends had received the HPV vaccination were less likely to support HPV vaccination mandates for both sexes (Model 3). This association was not significant among males. In fact, when compared to females, a significantly larger proportion of male participants reported not knowing if their friends had been vaccinated against HPV (61% for males versus 32% for females). This finding may indicate that females more openly discuss sensitive topics (eg, sex and vaccination practices) with friends and are more likely to engage in the same behaviors as members of their social/ peer group. Several possible rationales exist for vaccinating both males and females besides reducing their risk of illness. The first is equal protection. Males are also at risk for HPV-related cancers, thus vaccinating males can protect against HPV and limit its spread via heterosexual sexual activity.9,29 The second is equal responsibility. Although cervical cancer is among the most fatal ramifications of HPV, the burden of vaccination should not rest solely on females. The third is herd immunity. Vaccinating both sexes will increase overall vaccination rates in the population, thereby reducing the time needed to reach critical mass for protective coverage. The fourth is increased total coverage. Introducing and enforcing school-based mandates can serve as mechanism to vaccinate individuals who would not normally be able to afford or acquire vaccination.29 The effect of male vaccination on herd immunity has been and continues to be investigated. Many researchers have dismissed the cost effectiveness and utility of male vaccination except in cases where female coverage is low.30,31 However, the authors believe that this is an overly simplistic viewpoint for several reasons. First, receipt of the vaccination does not indicate one is HPV-free because individuals who have acquired the virus before vaccination are not cured by the vaccination and can serve as a reservoir of HPV.32 Second, subgroups of sexually active individuals and disparate populations may remain unvaccinated or undervaccinated, despite high national coverage. For example, many of the models examining HPV herd immunity have not included or fully considered the lesbian, gay, bisexual, and transgender (LGBT) community.30 Thus, if vaccination was restricted solely to females, then the men who have sex with men (MSM) subgroup would remain at disproportionately higher risk for infection and subsequent ramifications.
participants perceiving HPV and HPV vaccination as a female health issue, which may stem from the known association between HPV and cervical cancer as well as the focus of HPV vaccination advertisement to the female population. Thus, the low response rate among males may be because they ignored the request to participate due to their belief that the study did not apply to them. Data were self-reported; thus, the accuracy of perceptions and behaviors reported could not be confirmed. This study was cross-sectional, which limited our ability to determine causality. All data were collected at 2 universities in Texas, a state that may not represent a diverse political environment, and consequently, also may limit the ability to generalize findings beyond this sample. However, this study purposively focused on college students in Texas because the state has one of the highest rates of cervical cancer in the country and the lowest rates of HPV vaccination.10 Further, analyses in the current study may have omitted important variables for understanding HPV vaccination mandate support. This is evidence when examining the model fit statistics for regression models, which was larger for the male only model (Model 2) relative to the other 2 study models. These statistics indicate the selected study variables explained more variance in the dependent variable for males than for females. This also indicates that other variables not included in the study may have been important to include in the female model. For example, an individual’s own HPV vaccination status may be a strong predictor of mandate support. Whereas HPV vaccination status was collected in this study, this information was not collected from male participants. To examine this relationship among female participants, an additional analysis was performed that included HPV vaccination status in the logistic regression using only female participant data (Model 3). Findings from this sensitivity analysis indicate that females who have initiated or completed the HPV vaccination 3-dose cycle are significantly more likely to support HPV vaccination mandates for both sexes (data not shown).
Limitations This study is not without limitations. Despite the general representativeness of the study sample to the university populations, the low response rate could be attributed to self-selection bias and may limit the generalizability of these findings. The overrepresentation of females may be attributed to
Conclusion Although commonly viewed as a female issue, HPV vaccinations are approved for both sexes and can prevent a variety of HPV-related cancers. Despite the reported effectiveness of HPV vaccines, uptake remains low, which highlights the potential importance of introducing vaccination mandates for school-aged youth. Although much is known about factors influencing decisions to become vaccinated against HPV, this study is among the first to examine many of the same perceptions and behaviors and apply them to HPV vaccination mandates for school-aged boys and girls. Findings have potential to inform public health practitioners and health policymakers to understand the characteristics of young voters who support or oppose HPV
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Support for HPV Vaccination Mandates for Both Females and Males vaccination mandates. Findings also have potential to guide health education and promotion interventions to increase knowledge and awareness for HPV-related risk and the protective nature of vaccinations. Human Subjects Statement Approval for this study was independently received from Institutional Review Boards at Texas A&M University and Texas State University. Conflict of Interest Statement The authors have no conflicts of interests to disclose, financial or otherwise. References
1. Schiffman M, Castle PE, Jeronimo J, et al. Human papillomavirus and cervical cancer. Lancet. 2007;370(9590):890-907. 2. Satterwhite CL, Torrone E, Meites E, et al. Sexually transmitted infections among US women and men: prevalence and incidence estimates, 2008. Sex Transm Dis. 2013;40(3):187-193. 3. Finer LB, Philbin JM. Sexual initiation, contraceptive use, and pregnancy among young adolescents. Pediatrics. 2013;131(5):886-891. 4. Division of STD Prevention. Prevention of Genital HPV Infection and Sequelae: Report of an External Consultants’ Meeting. Atlanta, GA: Centers for Disease Control and Prevention (CDC); 1999:1-35. 5. Chao C, Velicer C, Slezak JM, Jacobsen SJ. Correlates for completion of 3-dose regimen of HPV vaccine in female members of a managed care organization. Mayo Clin Proc. 2009;84(10):864-870. 6. Centers for Disease Control and Prevention (CDC). Human papillomavirus vaccination coverage among adolescent girls, 2007-2012, and postlicensure vaccine safety monitoring, 2006-2013 - United States. MMWR Morb Mortal Wkly Rep. 2013;62(29):591-595. 7. Centers for Disease Control and Prevention (CDC). FDA licensure of quadrivalent human papillomavirus vaccine (HPV4, Gardasil) for use in males and guidance from the advisory committee on immunization practices (ACIP). MMWR Morb Mortal Wkly Rep. 2010;59(20):630-632. 8. Markowitz LE, Dunne EF, Saraiya M, et al. Quadrivalent human papillomavirus vaccine: Recommendations of the advisory committee on immunization practices (ACIP). MMWR Recomm Rep. 2007;56(RR-2):1-24. 9. Centers for Disease Control and Prevention (CDC). Recommendations on the use of quadrivalent human papillomavirus vaccine in males--advisory committee on immunization practices (ACIP), 2011. MMWR Morb Mortal Wkly Rep. 2011;60(50):1705-1708. 10. Dickerson JB, Smith ML, Ory MG. Increasing uptake of Gardasil among American adolescents: comparisons with the history of hepatitis B vaccination. Human Vaccines. 2011;7(2):211-219. 11. Centers for Disease Control and Prevention (CDC). National and state vaccination coverage among adolescents aged 13-17 years--United States, 2011. MMWR Morb Mortal Wkly Rep. 2012;61(34):671-677. 12. Centers for Disease Control and Prevention (CDC). National and state vaccination coverage among adolescents aged 13–17 Years—United States, 2012. MMWR Morb Mortal Wkly Rep. 2013;62(34):685-693. 13. Brewer NT, Fazekas KI. Predictors of HPV vaccine acceptability: a theory-informed, systematic review. Prev Med.
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2007;45(2):107-114. 14. Zimet GD. Understanding and overcoming barriers to human papillomavirus vaccine acceptance. Curr Opin Obstet Gynecol. 2006;18(Suppl 1):s23-s28. 15. Haber G, Malow RM, Zimet GD. The HPV vaccine mandate controversy. J Pediatr Adolesc Gynecol. 2007;20(6):325331. 16. Colgrove J, Abiola S, Mello MM. HPV vaccination mandates—lawmaking amid political and scientific controversy. N Engl J Med. 2010;363(8):785-791. 17. Schwartz JL. HPV vaccination’s second act: promotion, competition, and compulsion. Am J Public Health. 2010;100(10):1841-1844. 18. Kahn JA, Rosenthal SL, Hamann T, Bernstein DI. Attitudes about human papillomavirus vaccine in young women. Int J STD AIDS. 2003;14(5):300-306. 19. Centers for Disease Control and Prevention (CDC). Behavioral risk factor surveillance system questionnaire. 2010. Available at: http://www.cdc.gov/brfss/annual_ data/pdf-ques/2010brfss.pdf. Accessed April 5, 2014. 20. National Conference of State Legislatures. HPV vaccine (on-line). Available at: http://www.ncsl.org/research/ health/hpv-vaccine-state-legislation-and-statutes. aspx#2013-2014%20chart. Accessed February 6, 2014. 21. Tsai CJ, Griffin MR, Nuorti JP, Grijalva CG. Changing epidemiology of pneumococcal meningitis after the introduction of pneumococcal conjugate vaccine in the United States. Clin Infect Dis. 2008;46(11):1664-1672. 22. Bottiger M, Forsgren M. Twenty years’ experience of rubella vaccination in Sweden: 10 years of selective vaccination (of 12-year-old girls and of women postpartum) and 13 years of a general two-dose vaccination. Vaccine. 1997;15(14):1538-1544. 23. Bernstein AB, Hing E, Moss A, et al. Health Care in America: Trends in Utilization. Washington, DC: National Center for Health Statistics; 2003.1-135 24. Guttmacher Institute. Facts on American teens’ sexual and reproductive health (on-line). Available at: http:// www.guttmacher.org/pubs/FB-ATSRH.html. Accessed February 5, 2014. 25. Centers for Disease Control and Prevention (CDC). Key statistics from the national survey of family growth (online). Available at: http://www.cdc.gov/nchs/nsfg/key_ statistics.htm. Accessed April 5, 2014. 26. Acton RT, Burst NM, Casebeer L, et al. Knowledge, attitudes, and behaviors of Alabama’s primary care physicians regarding cancer genetics. 2000;75(8):850-852. 27. Wilkins-Haug L, Hill LD, Power ML, et al. Gynecologists’ training, knowledge, and experiences in genetics: a survey. Obstet Gynecol. 2000;95(3):421-424. 28. Centers for Disease Control and Prevention (CDC). What should I know about screening? (on-line). Available at: http://www.cdc.gov/cancer/cervical/basic_info/ screening.htm. Accessed May 31, 2014. 29. Gillison ML, Chaturvedi AK, Lowy DR. HPV prophylactic vaccines and the potential prevention of noncervical cancers in both men and women. Cancer. 2008;113(10 Suppl):3036-3046. 30. Brisson M, van de Velde N, Franco EL, et al. Incremental impact of adding boys to current human papillomavirus vaccination programs: role of herd immunity. J Infect Dis. 2011;204(3):372-37 6. 31. Chesson HW, Ekwueme DU, Saraiya M, et al. The costeffectiveness of male HPV vaccination in the United States. Vaccine. 2011;29(46):8443-8450. 32. Hildesheim A, Herrero R, Wacholder S, et al. Effect of human papillomavirus 16/18 L1 viruslike particle vaccine among young women with preexisting infection. JAMA. 2007;298(7):743-753.
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H
uman papillomavirus (HPV) is one of the most common sexually transmitted infections (STI) and has been identified as the leading cause of cervical cancer in the United States.1 In 2008, approximately 14 million Americans were estimated to be newly infected with HPV, over half of whom were youth between the ages of 15 to 24 years.2 Whereas the average age of first sexual intercourse in America is around age 17 years,3 engagement in sexual behaviors with direct skin-to-skin contact (including heavy petting and oral sex) may occur years before sexual intercourse and are known risk behaviors for HPV transmission.4 To date, the Food and Drug Administration has approved 2 vaccines (ie, Gardasil and Cervarix) to protect females and males against particularly virulent HPV strains. Both vaccines target HPV types 16 and 18 that are responsible for 70% of cervical cancers;5 moreover, Gardasil also protects against HPV types 6 and 11 that are responMatthew Lee Smith, Assistant Professor, Department of Health Promotion and Behavior, College of Public Health, University of Georgia, Athens, GA. Kelly L. Wilson, Associate Professor, Department of Health and Kinesiology, Texas A&M University, College Station, TX. Jairus C. Pulczinski, Research Assistant, Department of Health Promotion and Community Health Sciences, School of Public Health, Texas A&M Health Science Center, College Station, TX. Marcia G. Ory, Regents Professor, Department of Health Promotion and Community Health Sciences, School of Public Health, Texas A&M Health Science Center, College Station, TX. Correspondence Dr Smith; [email protected]
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ticipants (p = .001), those who generally supported HPV vaccination mandates (p < .01), and those who had had sexual intercourse (p = .005) were significantly more likely to support HPV mandates for both sexes. Conclusions: Identifying those who support HPV vaccination mandates is important for increasing vaccine uptake and reducing HPV-related cancers. Key words: human papilloma virus, vaccination, policy, mandate Am J Health Behav. 2014;38(6):831-838 DOI: http://dx.doi.org/10.5993/AJHB.38.6.5
sible for 90% of genital wart cases.6 Gardasil is approved for use among females and males between the ages of 9 and 26 years to protect females against cervical cancer and both sexes against genital warts.7 The Advisory Committee on Immunization Practices (ACIP) recommends routine initial HPV vaccination at age 11 or 12 years for girls, with additional vaccination cycles between the ages of 13 and 26 years.8 The ACIP recommends routine vaccination of males aged 11 and 12 years and vaccination for males aged 13 to 21 years who have not been vaccinated previously or received a full 3-dose regimen.8,9 Despite national vaccination recommendations (eg, from the President’s Cancer Panel) and guidelines as well as few known risks associated with the HPV vaccine,6 uptake rates are modest compared to other vaccinations recommended for adolescents.10,11 From 2007 to 2011, an increase in HPV vaccination coverage was observed among adolescent females; however, no change was seen in 2012.6 Approximately 53.8% of adolescent females had initiated the 3-dose HPV vaccination series, but only about 33% received all 3 recommended doses.12 HPV vaccine uptake among males remains exceedingly low relative to females.11 To increase HPV vaccination uptake rates among adolescents, efforts have been employed to understand obstacles to vaccination uptake. Identified factors contributing to HPV vaccination include perceiving the vaccine as safe, perceiving personal risk for contracting HPV, receiving a physician rec-
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Support for HPV Vaccination Mandates for Both Females and Males ommendation, and believing vaccination would not promote sexual activity among youth.13 These issues are complicated further by ethical concerns among members of the medical community and moral opposition from certain subgroups.14-16 The most influential strategy to increase vaccine uptake is to pass laws that mandate vaccination behavior;10 however, such regulations cannot pass without fostering vaccination acceptability and public support. Vaccine mandates can protect large numbers of individuals against HPV and associated cancers, which can directly reduce infection rates through herd immunity. Such effects have potential to reduce health inequalities caused by HPV. Despite potential public health benefits, HPV vaccination mandates were proposed and advocated for prior to establishing widespread support for the HPV vaccine. More specifically, before the broad public and authoritative agencies agreed upon vaccine recommendations, HPV mandate proposals were put forth.15 These actions may have resulted in damaging effects for HPV mandates and calls for coordinated approaches that simultaneously release vaccines into the market along with strict recommendations for use and mandates. Despite current resistance to HPV vaccine mandates for school attendance, the issue likely will be revisited as an important component of adolescent healthcare,17 especially as vaccination recommendations for males increase. Although the HPV vaccine is approved for males aged 9 to 26 years, the vaccine was originally recommended for use among females and marked as a preventive measure against cervical cancer. Even though the vaccine protects against anogential cancers for either sex, the disproportionate burden of these cancers on the female population marks them as the more appropriate target for the vaccination and associated mandates.6 Whereas anogential cancer mortality is lower among males, they serve as a reservoir for the virus and contribute to the spread of HPV in the female population.17 This fact, combined with their risk for HPV-related cancers and genital warts, makes males appropriate targets for the vaccine and associated mandates. Therefore, the following question arises: if new HPV vaccination mandates surface for school-aged youth, should mandates target both sexes? Utilizing a sample of young adults aged 18 to 26 years, the purposes of this exploratory study were to: (1) describe personal characteristics, health behaviors, normative beliefs, and HPV-related knowledge of young adults based on their support for HPV vaccine mandates for school-aged girls and boys; and (2) assess factors associated with support for HPV vaccine mandates for both sexes. College-aged individuals were selected because they comprise a unique audience that is transitioning into adulthood and that recently has become able to make healthcare decisions without parental consent. In many cases, these individuals will
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become parents in forthcoming years, thereby requiring them to make health-related decisions for themselves and their children. Additionally, these individuals represent a subset of potential voters who are eligible to impact healthcare issues. METHODS Participants and Procedures Data were collected from a sample of young adults enrolled in 2 large Texas universities using an Internet-delivered survey instrument hosted by Qualtrics. Participants were recruited at each institution via electronic mail (e-mail). Researchers disseminated e-mail messages to every enrolled student using university-regulated delivery systems (ie, a university service provided to investigators for the purposes of sending mass e-mails to students for research recruitment). Recruitment email text provided participants with the URL address for the Internet-based survey. After sending initial recruitment emails, a reminder email was distributed 5 days later. Data were collected over a 2-week period at each institution. Participation in this study was voluntary, no identifying information was collected from participants, and no incentives were provided to respondents for participating in the study. Of the 81,715 enrolled students who received the email (ie, total student enrollment of 49,129 and 32,586 at each institution, respectively), 3987 students responded to the survey (response rate = 4.9%) with 2513 participants completing the instrument (completion rate = 63.1%). Although participants both responding to and completing the instrument were representative of the student populations at these 2 universities in terms of age and race/ethnicity; the study sample had disproportionately more females (81% versus 47% and 56%, respectively). Participants who were over the age of 26 years (N = 469) were omitted from analyses based on specified study aims. To alleviate biased responses, participants who were married (N = 307), diagnosed with cervical cancer (N = 29), told they had HPV (N = 438) or genital warts (N = 153), or had an immediate family member with cervical cancer (N = 345) were removed from the study. Additionally, participants who reported they supported HPV vaccine mandates for only girls (N = 165) or only boys (N = 33) were omitted from analyses because cell sizes were inadequate for comparative purposes. Some participants cited more than one of these exclusionary responses so the usable final sample was 1322 young adults. Instrument Participants were surveyed using a questionnaire consisting of 76 multi-part items, which included skip patterns used to advance participants through the instrument based on provided responses. The instrument was comprised of a combination of Likert-type scales, closed-ended response items, and
Smith et al open-ended response items. The instrument used items previously tested and validated by other researchers.18,19 The authors also added items to assess participants’ perceptions about HPV vaccine mandates, facilitators and barriers of receiving HPV vaccinations, and health-related behaviors, among other items. Participants took approximately 15 minutes to complete the survey. Measures Dependent variable. The dependent variable for this study was participants’ support for HPV vaccination mandates for school-aged youth. Participants were asked: “If there was a HPV vaccine approved for both school-aged males and females, who do you think should be mandated to get the vaccine?” Possible response categories included “neither males nor females,” “males only,” “females only,” and “both males and females.” Based on the purposes of this study and the cell sizes for response choices, this variable was dichotomized. The response choices “males only” (N = 33) and “females only” (N = 165) were omitted. The recoded variable used in analyses contained the response choices “neither males nor females” and “both males and females.” Not supporting HPV vaccination mandates for either sex served as the referent group for logistic regression. HPV vaccine perceptions. Participants were asked: “In your opinion, would getting the HPV vaccine make it safer to have more sexual partners?” Response categories included “no” and “yes.” HPV-related knowledge. Participants were asked to complete 11 items intended to measure the extent to which they were knowledgeable about HPV.18 Respondents were asked to indicate which of the statements were true or false. For example, participants were asked to rate statements like: “A person may be infected and not know it,” “Pap smears can detect HPV,” “HPV can be cured with antibiotics,” and “Certain types of HPV cause cancer.” Response categories included “true,” “false,” and “I don’t know.” Items endorsed correctly were coded as “1,” and those endorsed incorrectly were coded as “0.” The HPV-related knowledge score ranged from 0 to 11 for this count variable. Number of friends vaccinated. Participants were asked to report the number of their friends who had already received the HPV vaccination.18 Response categories included “none,” “some,” “most or all,” and “I don’t know.” HPV vaccine mandate support by age group. Participants were asked to report their general support for individuals within specified age groups. Respondents were provided with the following definition and question: “A mandate is something that is required by law. Do you think the HPV vaccine should be mandated (eg, required by law) for those….?” Age groups provided to participants were “between the ages of 9 and 11,” “between the ages of 12 and 17,” and “between the ages of 18 and 26.” Participants responded to each age group
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separately. Response categories included “no” and “yes.” Sociodemographics. Personal characteristics of the participants included age (ie, 18 to 26 years), sex, race/ethnicity (ie, non-Hispanic white, nonwhite), and insurance status (ie, insured, uninsured). Statistical Analyses All statistical analyses were performed using SPSS (version 22). Frequencies were calculated for all major study variables, which were initially examined in relationship to respondents’ sex and reported support for HPV vaccination mandates for both sexes. Pearson’s chi-square tests were performed to assess the independence between dependent variable and categorized independent variables. Independent sample t-tests were used to examine mean differences for continuous variables. Three logistic regression models were fitted to examine factors associated with HPV vaccination mandate support for both sexes (ie, not supporting HPV vaccination mandates for either sex served as the referent group). One regression model was fitted using all study participant data. Then, one model was fitted using only male participant data and one model using only female participant data. Odds ratios, and 95% confidence intervals, and model fit statistics are reported for each regression model. RESULTS Sample Characteristics of study participants are presented in Table 1. Of the 1322 participants, 81.0% were female and 19.0% were male. Over 42% did not support HPV vaccination mandates for either school-aged girls or boys, and 57.8% supported HPV vaccination mandates for both sexes. The average age was 20.95 years (±1.96). Approximately 76% of participants were non-Hispanic Whites, and 67.5% reported having engaged in sexual intercourse. Most of the participants had health insurance (91.7%). On average, participants had HPV-related knowledge scores of 7.93 (±1.89) out of 11 possible points. Approximately 40% of participants reported some of their friends had received the HPV vaccine, and 10.2% reported most or all of their friends had received the HPV vaccine. When asked about general support of HPV vaccination mandates, 15.1% supported mandates for individuals between the ages of 9 and 11 years, 48.4% for individuals between the ages of 12 and 17 years, and 48.9% for individuals between the ages of 18 to 26 years. Over 27% of participants reported that getting the HPV vaccine would make it safer to have more sexual partners. Significant differences were observed when comparing sample characteristics by sex. On average, females were significantly younger (t = 5.28, p < .001) and had higher HPV-related knowledge scores (t = -5.89, p < .001) than their male counterparts.
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Support for HPV Vaccination Mandates for Both Females and Males
Table 1 Sample Characteristics by Sex and HPV Vaccine Mandate Support for Both Sexes Total (N = 1322)
Sex
Men (N = 448)
Women (N = 586)
χ2 or t
p
Neither Boys Nor Girls (N = 558)
Both Boys and Girls (N = 764)
χ2 or t
p
--
--
2.04
0.153
Male
19.0%
--
--
20.8%
17.7%
Female
81.0%
--
--
79.2%
82.3%
Age (18 to 26)
20.95 (±1.96)
21.58 (±2.17)
20.80 (±1.88)
5.28
< .001
20.83 (±1.89)
21.03 (±2.01)
-1.87
.062
Race/ethnicity
1.18
.278
21.16
< .001
Non-Hispanic white
76.3%
73.7%
76.9%
82.6%
71.7%
Non-white
23.7%
26.3%
23.1%
17.4%
28.3%
Insurance status
1.09
.296
0.48
.489
Uninsured
8.3%
10.0%
7.9%
7.7%
8.8%
Insured
91.7%
90.0%
92.1%
92.3%
91.2%
3.48
.062
47.47
< .001
32.5%
27.5%
33.6%
42.8%
24.9%
Ever had sexual intercourse No Yes HPV-related knowledge (0 to 11) Proportion of friends who received HPV vaccine
67.5%
72.5%
66.4%
57.2%
75.1%
7.93 (±1.89)
7.19 (±2.30)
8.10 (±1.74)
-5.89
< .001
7.87 (±1.88)
7.97 (±1.90)
-1.01
.312
93.70
< .001
52.04
< .001
None
12.0%
14.7%
11.4%
16.7%
8.6%
Some
40.2%
21.1%
44.7%
42.7%
38.5%
Most/All
10.2%
2.8%
12.0%
4.3%
14.5%
Don’t Know
37.5%
61.4%
31.9%
36.4%
38.4%
3.85
.050
123.18
< .001
No
84.9%
80.9%
85.8%
97.7%
75.5%
Yes
15.1%
19.1%
14.2%
2.3%
24.5%
0.24
.622
607.19
< .001
No
51.6%
53.0%
51.3%
91.2%
22.6%
Yes
48.4%
47.0%
48.7%
8.8%
77.4%
0.92
.337
623.17
< .001
No
51.1%
53.8%
50.4%
91.2%
21.7%
Yes
48.9%
46.2%
49.6%
8.8%
78.3%
15.34
< .001
11.03
.001
No
72.8%
62.9%
75.2%
77.6%
69.4%
Yes
27.2%
37.1%
24.8%
22.4%
30.6%
Support HPV vaccine mandates: ages 9 to 11
Support HPV vaccine mandates: ages 12 to 17
Support HPV vaccine mandates: ages 18 to 26
Getting HPV vaccine means can have more sex partners
A significantly larger proportion of females reported having larger proportions of friends who had received the HPV vaccine and a larger proportion of males reported not knowing their friends’ vaccination status (χ2 = 93.70, p < .001). Furthermore, a significantly larger proportion of males reported that getting the HPV vaccine would make it safer to have more sexual partners (χ2 = 15, p < .001). Significant differences were observed when comparing sample characteristics by whether or not participants supported HPV vaccination mandates for school-aged youth. A significantly larger proportion of participants supporting HPV vaccination mandates for both sexes were non-white (χ2 = 21.16, p < .001) and engaged in sexual intercourse (χ2 = 47.47, p < .001). A significantly larger proportion of participants supporting HPV vaccination man-
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dates for both sexes reported having larger proportions of friends who had received the HPV vaccine (χ2 = 52.04, p < .001). Furthermore, a significantly larger proportion of participants supporting HPV vaccination mandates for both sexes reported generally supporting HPV vaccination mandates for individuals between the ages of 9 and 11 years (χ2 = 123.18, p < .001), 12 and 17 years (χ2 = 607.19, p < .001), and 18 and 26 years (χ2 = 623.17, p < .001). A significantly larger proportion of participants supporting HPV vaccination mandates for both sexes reported that getting the HPV vaccine would make it safer to have more sexual partners (χ2 = 11.03, p < .001). Table 2 displays the results of logistic regression analyses explaining factors associated with participants supporting HPV vaccination mandates
Smith et al
Table 2 Factors Associated with Believing Boys and Girls Should Be Mandated to Receive the HPV Vaccine
Model 1
Model 2
Model 3
All Participants (N = 1322)
Men Only (N = 251)
Women Only (N = 1071)
95% CI
95% CI
95% CI
OR
p
Lower
Upper
OR
p
Lower
Upper
OR
p
Lower
Upper
Age
1.09
.065
1.00
1.19
1.38
.007
1.09
1.74
1.04
.480
0.94
1.15
Male
1.00
--
--
--
--
--
--
--
--
--
--
--
Female
1.63
.038
1.03
2.60
--
--
--
--
--
--
--
--
Non-Hispanic white
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Non-white
2.00
.001
1.34
2.99
4.46
.003
1.67
11.89
1.63
.032
1.04
2.54
Uninsured
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Insured
1.50
.205
0.80
2.81
6.65
.022
1.31
33.82
1.21
.595
0.60
2.41
Never had sexual intercourse
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Had sexual intercourse
1.71
.005
1.18
2.47
2.05
.190
0.70
6.00
1.73
.008
1.16
2.58
HPV-related knowledge
1.00
.969
0.91
1.10
0.98
.867
0.81
1.20
1.01
.911
0.90
1.12
Some friends received HPV vaccine
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
No friends received HPV vaccine
0.70
.072
0.47
1.03
1.04
.948
0.34
3.16
0.63
.035
0.41
0.97
Most/all friends received HPV vaccine
0.80
.413
0.47
1.36
1.27
.707
0.37
4.39
0.64
.148
0.35
1.17
Don’t know number of friends received HPV vaccine
0.96
.901
0.47
1.95
2.55
.612
0.07
95.87
0.85
.669
0.41
1.78
Not support HPV vaccine mandate: ages 9 to 11
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Support HPV vaccine mandate: ages 9 to 11
2.59
.009
1.27
5.26
1.93
.414
0.40
9.39
2.89
.011
1.27
6.56
Not support HPV vaccine mandate: ages 12 to 17
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Support HPV vaccine mandate: ages 12 to 17
8.49
< .001
5.51
13.07
12.59
< .001
3.50
45.31
8.22
< .001
5.16
13.08
Not support HPV vaccine mandate: ages 18 to 26
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Support HPV vaccine mandate: ages 18 to 26
10.93
< .001
7.32
16.32
16.20
< .001
5.36
49.00
10.24
< .001
6.62
15.84
Getting HPV vaccine means can have more sex partners: No
1.00
--
--
--
1.00
--
--
--
1.00
--
--
--
Getting HPV vaccine means can have more sex partners: Yes
1.13
.544
0.76
1.66
1.24
.673
0.46
3.30
1.17
.473
0.76
1.81
Nagelkerke R square = 0.658
Nagelkerke R square = 0.746
Nagelkerke R square = 0.643
Note. Referent Group: Believe males and females should NOT be mandated to receive the HPV vaccine
for school-aged girls and boys (ie, not supporting HPV vaccination mandates for either sex served as the referent group for all 3 models). In Model 1 using all participant data, females (OR = 1.63, p = .038), non-white participants (OR = 2.00, p = .004), and those who reported having sexual intercourse in their lifetime (OR = 1.71, p = .005) were significantly more likely to support HPV vaccination mandates for both sexes. Participants who reported supporting general HPV vaccine mandates for persons between the ages of 9 and 11 years (OR = 2.59, p = .009), 12 and 17 years (OR = 8.49, p < .001), and 18 and 26 years (OR = 10.93, p < .001) were significantly more likely to support HPV vaccination mandates for both sexes. In Model 2 using only male participant data, older participants (OR = 1.38, p = .007), non-white participants (OR = 4.46, p = .003), and those with health insurance (OR = 6.65, p = .022) were significantly more likely to support HPV vaccination mandates for both sexes. Males who reported sup-
porting general HPV vaccine mandates for persons between the ages of 12 and 17 years (OR = 12.59, p < .001) and 18 and 26 years (OR = 16.20, p < .001) were significantly more likely to support HPV vaccination mandates for both sexes. In Model 3 using only female participant data, non-white participants (OR = 1.63, p = .032) and those who reported having sexual intercourse in their lifetime (OR = 1.73, p = .008) were significantly more likely to support HPV vaccination mandates for both sexes. Females who reported none of their friends had received the HPV vaccine were significantly less likely to support HPV vaccination mandates for both sexes (OR = 0.63, p = .035). Participants who reported supporting general HPV vaccine mandates for persons between the ages of 9 and 11 years (OR = 2.89, p = .011), 12 and 17 years (OR = 8.22, p < .001), and 18 and 26 years (OR = 10.24, p < .001) were significantly more likely to support HPV vaccination mandates for both sexes.
Am J Health Behav.™ 2014;38(6):831-838
DOI:
http://dx.doi.org/10.5993/AJHB.38.6.5
835
Support for HPV Vaccination Mandates for Both Females and Males DISCUSSION Human papillomavirus vaccination is a controversial topic that is often polarizing. The protective nature of the vaccine against several types of cancer has encouraged multiple states to attempt passing HPV vaccination mandates that require school-aged children to obtain the vaccine prior to enrollment.20 Many claim this would be an effective strategy to protect youth because similar institutional mandates have increased vaccination uptake and coverage.10, 21, 22 However, in part because HPV is sexually transmitted, HPV vaccination mandates have resulted in political, religious, and ethical opposition.15, 16 Alongside the ongoing controversy, HPV vaccination and associated mandate discussions have focused primarily on vaccinating young females because vaccine-marketing campaigns have largely surrounded cervical cancer prevention. However, the availability of approved HPV vaccinations for males has widened the potential market, yet uptake remains low.12 Because of recent proposals and votes to pass legislation about HPV vaccinations among school-aged youth in many states, the current study investigated factors associated with HPV vaccination mandate support for both males and females. Whereas a variety of reasons influence healthcare access and utilization among Americans,23 examining mandate support among the college-aged population is important because it has potential to influence grand-scale policies that uniformly protect school-aged youth. More specifically, collegeaged individuals are a critical population to study in the context of HPV vaccinations and mandates because: (1) this age group is a high-risk population for HPV and other STIs; (2) college has been identified a time for sexual initiation and exploration, which increases the risk for contracting HPV; and (3) this age group is considered to be a group of young voters, many who have just recently turned 18 years, are potentially future parents, and are now eligible to make their own health decisions as well as vote about important health policies. In this study, HPV vaccination mandate support was modest for individuals aged 9 to 11 years (15.1%) but increased to about 50% for individuals aged 12 to 26 years. Even among supporters of HPV vaccination mandates for both sexes, only 24.5% supported vaccinations for individuals aged 9 to 11years, compared to over 77% for the individuals aged 12 to 26 years. These findings highlight a general disconnect with FDA and ACIP HPV vaccination recommendations for those ages 9 to 11 years.8,9 The lack of mandate support for youth ages 9 to 11 years may stem from the belief these youth are not sexually active, are at low risk for HPV, and thus, should not be vaccinated. However, for the vaccine to be successful, it should be administered to those individuals before exposure to the virus. In addition, considering the average age of sexu-
836
al debut is approximately 17 years in the United States24,25 (and that kissing, petting, and fellatio/ cunnilingus may occur prior to intercourse), this younger population should be considered an important demographic for vaccine mandate strategies. Over half of study participants (57.8%) supported HPV vaccination mandates for both sexes. Bivariate analyses revealed personal characteristics (ie, being non-white), behaviors (ie, being sexually active), and peer group characteristics (ie, having more friends vaccinated for HPV) were associated with supporting HPV vaccination mandates for both sexes. However, multivariate analyses revealed that sex, being sexually active, and general mandate support for ages 9 to 26 years were significantly related to mandate support for both sexes. These findings are interesting, yet not unexpected. Although it seems intuitive that participants who generally supported vaccination mandates would be more likely to support such mandates for both sexes, it is interesting that the rate of mandate support for both sexes exceeded general support rates for all age groups included in study analyses. This finding may indicate participants recognized the shared responsibility of males and females in HPV transmission and subsequent genital warts and cancers. Conversely, this finding may indicate that participants recognize the risk HPV introduces for warts and cancers among males. When comparing study findings by participant sex, females were significantly more likely to support mandates for both sexes. This may indicate females recognized the potential of mandates for both sexes to provide greater protection and that being vaccinated is a shared responsibility for both sexes. Conversely, lesser mandate support among males may indicate they still perceive HPV vaccination as a female-related health issue. Sex-based mandate support differences may also be explained by other study findings. The average HPV knowledge score for males was lower than for females, which may suggest males need more education about HPV and related modes of transmission/protection. Higher HPVrelated knowledge among females may be because they more regularly interact with healthcare providers during gynecological examinations.26,27 Additionally, females who reported having sex were more likely to support mandates for both sexes, which supports this finding in that sexually active females are recommended to receive regular Pap tests,28 This knowledge-related interpretation may be further supported by the finding that males who had insurance were significantly more likely to support mandates for both sexes. This association was not statistically significant among females. This finding may indicate that males with insurance interact with physicians more than their male counterparts without insurance, which could contribute to their HPV-related knowledge. Findings suggest that social influences also may
Smith et al impact mandate support. For example, study findings showed that female participants who reported none of their friends had received the HPV vaccination were less likely to support HPV vaccination mandates for both sexes (Model 3). This association was not significant among males. In fact, when compared to females, a significantly larger proportion of male participants reported not knowing if their friends had been vaccinated against HPV (61% for males versus 32% for females). This finding may indicate that females more openly discuss sensitive topics (eg, sex and vaccination practices) with friends and are more likely to engage in the same behaviors as members of their social/ peer group. Several possible rationales exist for vaccinating both males and females besides reducing their risk of illness. The first is equal protection. Males are also at risk for HPV-related cancers, thus vaccinating males can protect against HPV and limit its spread via heterosexual sexual activity.9,29 The second is equal responsibility. Although cervical cancer is among the most fatal ramifications of HPV, the burden of vaccination should not rest solely on females. The third is herd immunity. Vaccinating both sexes will increase overall vaccination rates in the population, thereby reducing the time needed to reach critical mass for protective coverage. The fourth is increased total coverage. Introducing and enforcing school-based mandates can serve as mechanism to vaccinate individuals who would not normally be able to afford or acquire vaccination.29 The effect of male vaccination on herd immunity has been and continues to be investigated. Many researchers have dismissed the cost effectiveness and utility of male vaccination except in cases where female coverage is low.30,31 However, the authors believe that this is an overly simplistic viewpoint for several reasons. First, receipt of the vaccination does not indicate one is HPV-free because individuals who have acquired the virus before vaccination are not cured by the vaccination and can serve as a reservoir of HPV.32 Second, subgroups of sexually active individuals and disparate populations may remain unvaccinated or undervaccinated, despite high national coverage. For example, many of the models examining HPV herd immunity have not included or fully considered the lesbian, gay, bisexual, and transgender (LGBT) community.30 Thus, if vaccination was restricted solely to females, then the men who have sex with men (MSM) subgroup would remain at disproportionately higher risk for infection and subsequent ramifications.
participants perceiving HPV and HPV vaccination as a female health issue, which may stem from the known association between HPV and cervical cancer as well as the focus of HPV vaccination advertisement to the female population. Thus, the low response rate among males may be because they ignored the request to participate due to their belief that the study did not apply to them. Data were self-reported; thus, the accuracy of perceptions and behaviors reported could not be confirmed. This study was cross-sectional, which limited our ability to determine causality. All data were collected at 2 universities in Texas, a state that may not represent a diverse political environment, and consequently, also may limit the ability to generalize findings beyond this sample. However, this study purposively focused on college students in Texas because the state has one of the highest rates of cervical cancer in the country and the lowest rates of HPV vaccination.10 Further, analyses in the current study may have omitted important variables for understanding HPV vaccination mandate support. This is evidence when examining the model fit statistics for regression models, which was larger for the male only model (Model 2) relative to the other 2 study models. These statistics indicate the selected study variables explained more variance in the dependent variable for males than for females. This also indicates that other variables not included in the study may have been important to include in the female model. For example, an individual’s own HPV vaccination status may be a strong predictor of mandate support. Whereas HPV vaccination status was collected in this study, this information was not collected from male participants. To examine this relationship among female participants, an additional analysis was performed that included HPV vaccination status in the logistic regression using only female participant data (Model 3). Findings from this sensitivity analysis indicate that females who have initiated or completed the HPV vaccination 3-dose cycle are significantly more likely to support HPV vaccination mandates for both sexes (data not shown).
Limitations This study is not without limitations. Despite the general representativeness of the study sample to the university populations, the low response rate could be attributed to self-selection bias and may limit the generalizability of these findings. The overrepresentation of females may be attributed to
Conclusion Although commonly viewed as a female issue, HPV vaccinations are approved for both sexes and can prevent a variety of HPV-related cancers. Despite the reported effectiveness of HPV vaccines, uptake remains low, which highlights the potential importance of introducing vaccination mandates for school-aged youth. Although much is known about factors influencing decisions to become vaccinated against HPV, this study is among the first to examine many of the same perceptions and behaviors and apply them to HPV vaccination mandates for school-aged boys and girls. Findings have potential to inform public health practitioners and health policymakers to understand the characteristics of young voters who support or oppose HPV
Am J Health Behav.™ 2014;38(6):831-838
DOI:
http://dx.doi.org/10.5993/AJHB.38.6.5
837
Support for HPV Vaccination Mandates for Both Females and Males vaccination mandates. Findings also have potential to guide health education and promotion interventions to increase knowledge and awareness for HPV-related risk and the protective nature of vaccinations. Human Subjects Statement Approval for this study was independently received from Institutional Review Boards at Texas A&M University and Texas State University. Conflict of Interest Statement The authors have no conflicts of interests to disclose, financial or otherwise. References
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