Abstract
The aims of the study were to assess the awareness and knowledge of HPV vaccination among female university and technological institutes students, and their association with vaccine uptake, and to identify the variables associated with higher levels of knowledge.
We conducted a cross-sectional study among females (age 18–26 y) at institutions of higher education (universities and technological institutes) in Athens (Greece). Data was collected by way of a self-completed questionnaire that included questions on vaccine uptake and four questions about knowledge. A new variable was created by adding up the correct answers (range 0–4) and categorizing them as “low level” (0–2) and high level of knowledge (> 2).
Independent variables included: Vaccine uptake, socio-demographic characteristics and health and sexual behavior variables.
3,153 female students took part in this research (participation rate 87%), 25.82% of whom were vaccinated against HPV. Most participants (97.15%) correctly answered the question about the existence of HPV, but only 28.41% knew at which age the vaccination is recommended. Overall, 59.1% of respondents had a high level of knowledge regarding the vaccine. The multivariate logistic model showed that being vaccinated was positively and significantly associated with a high level of knowledge. Positive predictors of higher levels of knowledge were: older age; being in a relationship; being a health sciences student; past HPV infection.
In conclusion, the level of knowledge and vaccine uptake among female higher-education students in Greece was below desirable levels. A high level of knowledge is positively associated with vaccine uptake. Health education efforts are needed to improve knowledge among all higher education students in Greece.
Cervical cancer is the second most common cancer among women worldwide.Citation1 A previous HPV infection is required for the development of cervical cancer.1Women between the ages of 15–24 constitute half of the population infected with the HPV virus. This population includes many college-aged students.Citation2-Citation4
In Greece, estimates for year 2010 indicate that 307 women were diagnosed with cervical cancer (crude incidence rate: 5.5 cases per 100,000 people) and 159 died from the disease.Citation5
The advent of HPV vaccines, with the potential to significantly decrease the cervical cancer burden worldwide in generations to come, presents a remarkable public health achievement.Citation1,Citation6 Greece was one of the first countries in the European Union to introduce HPV vaccines to its National Vaccination Programme.Citation7 Since January 2008 the cost of vaccination has been covered by social security for females aged 12 to 26.Citation8
Despite this fact, HPV vaccine uptake in Greece is low, with figures around 10–11% for women aged 16 to 28 and students.Citation9,Citation10
Assessing awareness and knowledge in a diverse sample is essential to gaining a balanced picture of the public’s understanding of HPV.Citation11 Studies in European countries have shown that HPV awareness figures ranged between 14% and 30%.Citation9 Knowledge is one of many predictors of protective sexual behavior; however, knowledge levels of the HPV vaccine are poor.Citation4,Citation6,Citation11-Citation17 HPV knowledge levels may be an important determinant for vaccine acceptance and uptake.Citation12 Increased knowledge will be useful for supporting the decision-making process because, in the case of HPV vaccination, decisions are often made without adequate information.Citation15,Citation16
The aims of the current study are to assess the awareness and knowledge of HPV vaccination and their association with vaccine uptake. A further aim is to identify the variables associated with higher levels of knowledge. A final aim of the study is to determine the difference in knowledge levels between female university and college students studying health sciences and those not studying health sciences.
We conducted a cross-sectional, epidemiological study on the levels of knowledge of the HPV vaccine among female university and college students studying non-health sciences and health sciences. The study population was comprised of female higher-education students in Athens (Greece) at all the institutions of higher education (seven universities and two technological institutes) in the city.
Data was collected by way of a self-completed questionnaire. In 2010, we conducted a pilot study that included 184 students from the Faculty of Nursing and Faculty of Dentistry in order to clarify whether the participants could understand the questions. A necessary sample size of 3,153 women was estimated assuming the following: 5% type I error; 90% power (1-β), 50% of “yes” or “no” answers to dichotomous variables in the questionnaire; and accuracy of 5%. In order to obtain a representative sample, the number of participants from each institution was proportional to its total number of students. The female students were recruited at each institution using a consecutive random sampling method.
Information was collected by a single specially-trained research nurse at the educational institutions. The nurse invited the students to participate after explaining the objectives of the study and guaranteeing the anonymity of the responses to the questionnaire. Inclusion criteria were: age between 18–26 y old, student of a higher-education institution in Athens and ability to speak Greek. The data collection period lasted 13 mo (September 2010−October 2011). The questionnaire included questions on vaccine uptake and different aspects of the HPV vaccine. To assess knowledge we used the following questions:
Q1: Do you know whether cervical cancer is caused by a virus? (Correct answer: YES).
Q2: Do you know whether there is a useful vaccine against cervical cancer? (Correct answer: YES).
Q3: Do you know which age group the vaccine is recommended for? (Multiple choice question with only one correct answer.) Options were: (1) < 9 y old; (2) 9–14 y old; (3) 14–18 y old; (4) 18–26 y old and (5) 9–26 y old (Correct answer Q4: Do you know which gender the vaccine is recommended for? (Correct answer: Female). We created a new variable by adding up the correct answers (range 0–4), and categorizing them as follows: low level of knowledge (0–2 correct answers) and high level of knowledge (3–4 correct answers).
A question regarding sources of information on the HPV vaccine was also included. The following independent variables were analyzed: Vaccine uptake three doses (yes /no). Socio-demographic characteristics including: age, current relationship status, and accessibility to Health Care Services. Health and sexual behavior variables including: smoking habits, previous sexual history (yes/no), number of sexual partners and contraceptive use. Condom use information was also collected with the question: Do you use a condom in your sexual relations? Providing three possible answers: “Always,” “Sometimes,” “Not usually” and categorized for analysis as “Always” vs. “Sometimes” and “Not usually.” Previous HPV infection was assessed using the questions: “Have you ever suffered from genital warts or have you been diagnosed with an HPV infection?” and “Do you know whether any family member or friend has ever suffered from genital warts or has been diagnosed with an HPV infection? Both questions had three possible answers: “Yes,” “No” or “I don’t know.”
The level of knowledge according to study variables was calculated by estimating the proportion of women who answered correctly to HPV-related questions and the 95% confidence interval. We estimated the level of knowledge for the total sample, among female non-health sciences and health sciences college students. The chi-square test was used to calculate and compare levels of high knowledge. Predictors of high levels of knowledge about the vaccine among the groups analyzed were determined by multivariate logistic regression models so that, using high knowledge as a dependent variable, we could determine which of the study variables was independently associated with high levels of knowledge. We have also conducted two multivariate logistic regression models (among non-health sciences and health sciences students) so that, using uptake as a dependent variable, we could determine which of the study variables, including high knowledge, was independently associated with adherence to the vaccine.
The multivariate logistic regressions were conducted using the variables, which, in the bivariate analysis, were statistically significant and those, which, although not statistically significant, were of interest from a healthcare and epidemiological viewpoint. Variables were eliminated, one at each step, according to their significance in the model used (Wald statistic) and considering the model’s goodness of fit with regard to the previous step (likelihood ratio test). The measure of association was calculated using adjusted odds ratios (OR) and 95% confidence intervals.
Estimates were made using the STATA version 11.0 program (StataCorp LP) and statistical significance was established as two-tailed α < 0.05.
The questionnaire was anonymous and was approved by the “Ethics Committee” of the University of Athens. All education institutions gave permission for the questionnaire to be conducted at their institutions. Written informed consent was obtained from all participants. No incentive was offered to students to participate.
The results were as follows: 3,624 female students (aged between 18 and 26 and studying at higher-education institutions in Athens, Greece) were invited to take part in this research. A total of 3,153 women took part, thus giving the study a participation rate of 87%. 60.74% of participants were aged between 18–20 y and 33.81% were aged between 21–26 y. The percentage of women who reported being vaccinated against HPV was 25.82%. Within the study group, 63.65% of participants were university students and 36.35% came from technological institutes. Furthermore, 38.1% were health sciences students and 61.9% were non-health sciences students. Vaccination coverage was 27.3% and 24.9% for health sciences and non-health sciences students respectively (p < 0.01) According to socio-demographic data, the majority of respondents: were in a relationship (59.94%), had difficulty accessing healthcare services (59.05%), had never visited the gynecologist (68.51%) and had had a sexual experience (74.25%).
Most participants (97.15%) correctly answered the question about the existence of a vaccine against cervical cancer (Q2). The lowest rate of correct answers (28.41%) was found for the question asking at which age the vaccination is recommended (Q3). Correct answers reached 51.6% for Q1 and 92.4% for Q4.
The most frequent source of information about the vaccination was the media (55.8%), followed by parents (48.8%), gynecologist (34.3%), friends (26.3%), school (19.5%) and healthcare providers other than gynecologist (19.3%).
and describe the distribution and proportion of high levels of knowledge regarding the HPV vaccine according to the study variables and among the groups analyzed (non-health sciences students, health sciences students and global). Overall, 59.1% of respondents had a high level of knowledge about the vaccine, specifically 67.5% of health sciences students and 54.0% of non-health sciences students (p < 0.01). In bivariate analysis, among all students, the variables which were significantly associated with a high level of knowledge were: being 21–26 y of age; being vaccinated (67.4% vaccinated vs. 56.2% non-vaccinated); being in a relationship and HPV infection of family or friends.
Table 1. Distribution and proportion of Greek female higher-education students with a high level of knowledge regarding HPV vaccine by socio-demographic variables, HPV vaccination, smoking habits and accessibility to healthcare services according to study groups.
Table 2. Distribution and proportion of Greek female higher-education students with a high level of knowledge regarding HPV vaccine by health and sexual behavior variables, including according to study groups.
summarizes the adjusted ORs and 95% CIs obtained with the multivariate logistic model, in which a high level of knowledge about the HPV vaccine was the dependent variable. Being vaccinated was positively and significantly associated with a high level of knowledge among the total sample (OR 1.64 95% CI 1.38–1.95), among non-health sciences students (OR 1.84 95% CI 1.48–2.28) and among health sciences students (OR 1.34 95% CI 1.01–1.78).
Table 3. Independent predictors of high level of knowledge regarding the HPV vaccine among Greek female higher-education students according to study groups.
Health sciences students had higher knowledge levels of the HPV vaccine than non-health sciences students (OR 1.83 95% CI 1.57–2.14) after adjusting for confounding factors.
Among health sciences students, positive predictors of higher levels of knowledge were: older age (21–26 y) (OR 1.12; 95% CI 1.01–1.33); being in a relationship (OR 1.84; 95% CI 1.48–2.28); and past HPV infection (OR 1.70; 95% CI 1.35–2.14). On the other hand, difficulties in access to healthcare services were a negative predictor (OR 0.80; 95% CI 0.66–0.96). For non-health sciences students the positive predictors included: older age (21–26 y) (OR 1.65; 95% CI 1.25–2.17); being in a relationship (OR 1.55; 95% CI 1.21–1.99); and past HPV infection (OR 1.48; 95% CI 1.01–1.78). No negative predictors were found.
Multivariate models analyzing the predictors of vaccine uptake among female non-health sciences students showed that a high level of knowledge (OR 1.95; 95% CI 1.53–2.49), being nonsmokers (OR 1.36; 95% CI 1.05–1.76) and any previous visit to a gynecologist (OR 1.73; 95% CI 1.28–2.32), increased adherence. Also a higher educational level of the parents was also associated with uptake with an OR for secondary education of 1.82 (95% CI 1.06–3.12) and for higher education an OR of 2.34 (95% CI 1.40–3.91), using primary education as the reference category.
Among female health sciences students, higher knowledge increased vaccine uptake by 1.28 (95% CI 1.01–3.12) and any previous visit to the gynecologist by 2.06 (95% CI 1.44–2.95).
The present survey describes the awareness and levels of knowledge of the HPV vaccine and its association with vaccine uptake. Furthermore, it identifies the variables which are associated with a higher level of knowledge and the difference in knowledge between female non-health sciences and health sciences college students.
Only a few European and American studies have assessed HPV-related knowledge in young adults.Citation12 Worldwide, several surveys have shown that female college students (18–25 y) had moderate levels of knowledge about the HPV vaccine, which may partly explain the limited HPV vaccination coverage.Citation3,Citation17
Several studies have been conducted in Greece on different aspects of HPV infection and vaccine. Dinas K et al. assessed the knowledge of HPV infection in 107 midwives and 29 graduating midwifery students finding, that more midwives (78.5%) were aware that a viral infection causes cervical cancer than midwifery students (48.3%).Citation18 In our population, a similar proportion of students (51.6%) gave a correct answer to the question: Do you know whether cervical cancer is caused by a virus?. In the northwest of Greece, a questionnaire answered by 1,012 women showed that 50 percent of the responders did not identify HPV as the cause of cervical cancer and 38% were not aware of the HPV vaccine.Citation10 Among our population the question: Do you know whether there is a useful vaccine against cervical cancer? was answered correctly by over 97% of the students. The different age distribution may explain such different figures. Results from a survey conducted in 18- to 25-y-old students from six vocational schools in Berlin showed that 95% of the women were aware of the ‘vaccine against cervical cancer’, but only half of them had heard of HPV.Citation12
In our sample, women who had been vaccinated had a higher level of knowledge (OR 1.83 95% CI 1.57–2.14) and this result is consistent with previous reports.Citation2,Citation19 Possible explanations for this association could include: those who are vaccinated engage in more preventive behaviors, receive more information from health providers, and as a result, have higher levels of knowledge about health.
In the total sample, an older age and being in a relationship were positive predictors of higher levels of knowledge about the vaccine. This finding is in agreement with another study, which assessed knowledge about HPV, HPV vaccination and cervical cancer among ethnically-diverse female university students. The study looked at a total sample of 650 female students and found that participants over 21 y of age (65.7% vs. 34.3%) and those who were in a relationship (55.2% vs. 44.8%), were more likely to have heard of the HPV vaccine.Citation4
Likewise, a history of HPV infection was positively associated with higher levels of knowledge. This result is consistent with a previous study, which found that those with past HPV infections were more likely to have higher levels of knowledge about the vaccine.Citation12
In the present study, educational level was not found to be significant; this may be explained by the fact that all participants were relatively highly educated. As expected, health sciences students had the best level of knowledge about the vaccination. This finding is consistent with a cross-sectional study conducted in the Netherlands with a sample of 600 college students aged between 18–25 y, which found that medical sciences students had the best knowledge of the vaccine.Citation17
In general sources of information (on health issues?) are the media, family and health providers. The media play an important role in informing and educating the public about health issues.Citation20 Similar to many previous studies, we also observed that the most frequent source of information was the media (55.8%).Citation4,Citation11,Citation12,Citation16,Citation20,Citation21 Despite the fact that a physician’s recommendation is very important and that health providers are the most trusted source of medical information, our results found that only 34.3% and 19.3% of respondents had received information from a gynecologist and healthcare services respectively.Citation16,Citation22
Although knowledge is not a direct predictor of health behavior, it is a key first step to the success of any health intervention.Citation16 Interventions on college campuses should stress vaccination as a normative behavior because college students are an at-risk population for these kinds of infections.Citation16,Citation23-Citation25 Furthermore, educational campaigns that focus on the efficacy, safety, benefits and attributes of HPV vaccination will be needed for the successful implementation of a vaccine program.Citation26,Citation27
Cooperation between healthcare providers, institutes and the media in promoting HPV awareness and knowledge by offering adequate information would increase the level of knowledge about HPV vaccination and, as a result, vaccine uptake among college students.
The main strength of the present study is that the sample size is, to our best knowledge, the largest used so far in any investigation into HPV vaccine knowledge, awareness and uptake among female higher-education students in Greece or elsewhere. Furthermore, we collected a large number of socio-demographic, health and sexual behavior variables that were controlled in the multivariate analysis as to their possible role as confounding factors.
However, there are a number of potential limitations. First, it is a cross-sectional survey, thus causality cannot be inferred. Second, the fact that it is based on self-reported information probably means that the level of knowledge is likely to be overestimated, although self-reporting is a cost-effective and feasible method for gathering data from large population samples. Third, the study sample included only higher-education students; since educational level is a variable associated with levels of knowledge, our result cannot be extrapolated to the general Greek population. Furthermore, our data are only representative of higher-education students in Athens (Greece). Therefore, in the best case scenario, data could be considered representative of the higher-education student population in this country but never of the entire Greek female population aged 18–26 y. Finally, the participation rate was 87%; therefore, a possible non-response bias should be taken into consideration.
In conclusion, the level of knowledge and vaccine uptake among female higher-education students in Greece was below desirable levels. High knowledge is positively associated with vaccine uptake. It is noteworthy that even the health sciences students had low levels of knowledge about the vaccine. The majority of studies agree that vaccine uptake could be improved through provision of information; ensuring that parents are well informed and girls are educated about the vaccine; involving community groups and by extending availability of the vaccine into community settings as well as in schools and universities.Citation12,Citation18-Citation24 Increasing knowledge about human papillomavirus (HPV) and HPV vaccine is a potentially important way to increase vaccination rates. Therefore educational interventions, which represent a simple yet potentially effective strategy for increasing HPV vaccine uptake, must be implemented in Greece.
| Abbreviations: | ||
| HPV | = | human papillomavirus |
Disclosure of Potential Conflicts of Interest
No potential conflicts of interest were disclosed.
Related Research Data
References
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