Effects of different educational interventions on cervical cancer knowledge and human papillomavirus vaccination uptake among young women in Japan: Preliminary results of a cluster randomized controlled trial

Abstract

The incidence and mortality rates of cervical cancer are increasing among young Japanese women. In November 2021, the Japanese Ministry of Health, Labour, and Welfare reinstated the active recommendation of the human papillomavirus (HPV) vaccine, after it had been suspended in June 2013 due to reports of adverse reactions. However, vaccine hesitancy is prevalent in the younger generation in Japan. To identify obstacles to vaccine uptake, we conducted a randomized study using different methods to provide educational content to improve health literacy regarding cervical cancer and HPV vaccination among Japanese female students. We surveyed 188 Japanese female students, divided into three groups according to the intervention: no intervention, print-based intervention, and social networking service-based intervention. Twenty questionnaires and the Communicative and Critical Health Literacy scales were used as health literacy scales. Participants' knowledge and health literacy improved regardless of the method of education. In fact, participants acquired proper knowledge when given the opportunity to learn about the importance of the disease and its prevention. Therefore, medical professionals in Japan must provide accurate scientific knowledge regarding routine HPV vaccination and the risk of cervical cancer in young women to improve their health literacy and subsequently increase HPV vaccination rates in Japan, which may lead to cervical cancer elimination. Trial registration number: UMIN000036636.

Fig 1. Odds ratios for "high health literacy" in the third survey, adjusted for CCHL scale scores.

Odds ratio (OR) for being “highly health literate” in the third survey. Logistic regression analysis was used to estimate the adjusted ORs and 95% confidence intervals (CIs) for Communicative and Critical Health Literacy (CCHL) scale scores (response variable: 1 = CCHL “high” in the 3^rd survey, 0 = “low”).

Fig 2. Subgroup analyses of questionnaire total scores and CCHL scale scores.

a–d: There are significant differences in the total scores of the questionnaire depending on whether participants were students at medical facilities and whether they had received HPV vaccinations before the study. e, f: No significant differences were found between the average Communicative and Critical Health Literacy (CCHL) scale scores obtained in the first survey between subgroups defined by HPV vaccination. HPV complete group: those who had already completed three doses of the HPV vaccine at the start of the study.

Fig 3. Comparison of average differences in CCHL scale scores.

a, b: Comparison of groups based on the average of the differences in the Communicative and Critical Health Literacy (CCHL) scale scores between the first and third surveys. There are no significant differences among the three groups. Interestingly, in the print-based group, no improvement can be observed; rather, a slight regression in literacy can be noted. c–e: Comparison of average CCHL scores in the first and third surveys, and the difference between the first and third surveys, in groups defined by the presence of family members in the medical profession. In the group of participants with medical professionals as family members, a slight regression can be observed in the difference in CCHL scale scores between the first and third surveys. c: First questionnaire. d: Third questionnaire. e: Difference between the first and third questionnaires. The difference is more pronounced in the negative, with a higher improvement observed when there is no family member in the medical profession.