Effects of an educational health promotion intervention to improve human papillomavirus vaccination acceptance and uptake among adolescent girls: a cluster randomized controlled trial.

BACKGROUND: Human Papillomavirus (HPV) is the most common sexually-transmitted infection worldwide and the primary cause of cervical cancer. Although timely vaccination can prevent HPV infection and reduce the risk of cervical cancer, vaccine uptake among target groups such as adolescent girls is suboptimal. This study aimed to investigate the effects of a school-based educational health promotion intervention to improve HPV vaccine acceptance and uptake among young adolescent girls. METHODS: A cluster randomized controlled trial was conducted with 1,340 female adolescents (Mean age: 15.3 years [S.D.: 1.1]) recruited from 18 secondary schools. Recruited schools and the respective participants were randomized to either the intervention or control group in a 1:1 ratio. The school-based intervention was delivered by a registered nurse and included a health talk, small group discussions, and an online game covering topics such as stages of cervical cancer, HPV infection, and HPV vaccination. Outcome measures were participants' uptake of HPV vaccination, intention to receive HPV vaccination, and knowledge and attitudes towards HPV vaccination, which were collected at either or both 1-month and 1-year post-intervention. Data were analyzed through a random intercept mixed-effects model. RESULTS: No significant differences were found in the HPV vaccine uptake rate and uptake intention of the two groups, though more participants in the intervention group (11.9%) were vaccinated at 1-year post-intervention compared to those in the control group (7.9%). Significant improvements were found in the intervention group's attitudes towards HPV vaccination, particularly in the subscales of Barriers (B=-2.20, 95% CI, [-3.46, -0.94], p = 0.001), Risk denial (B=-0.82, 95% CI, [-1.60, -0.05], p = 0.038), and Uncertainty (B = 0.72, 95% CI, [0.16, 1.27], p = 0.011). Significant improvements were also found in the intervention group's knowledge of HPV (B = 0.94, 95% CI, [0.16, 1.72], p = 0.018). CONCLUSIONS: The programme was beneficial in improving adolescent girls' knowledge and attitudes, though there is room for optimization in order to significantly improve vaccination intent and uptake. Future studies may investigate lengthier interventions involving other stakeholders such as parents and healthcare providers. An adapted programme may also be investigated among other demographics such as older females and adolescent boys. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04438291; Registration date: 2020-06-18.