Effectiveness of a school-based health literacy intervention in improving adolescent health literacy and the intention to take health-promoting actions.

BACKGROUND: There is a gap in theory-based interventions targeting adolescent health literacy. This study evaluated the impact of a school-based health literacy intervention on self-efficacy, health literacy awareness, situation, and intentions to take health-promoting actions among adolescents in community schools in Surkhet, Nepal. METHODS: This study followed a pre-test post-test quasi-experimental design. Based on identified health literacy needs, this study employed a five-step intervention mapping approach to design, implement, and evaluate health literacy interventions. A modified Delphi survey with interdisciplinary health experts was conducted to validate its main components, ensuring contextualisation. It was implemented over 13 classroom sessions in the intervention groups via the SHOWED questioning framework (What do you see here? What is happening? How does this relate to our lives? Why does the problem exist? What can we do?), led by nine interdisciplinary facilitators. Of the N = 468 participants, 144 participated in the intervention group and 324 participated in the non-intervention group. To evaluate the intervention's effectiveness, the same self-administered questionnaires, such as HL awareness, HLS-Child-24-Nep, health-promoting actions, and self-efficacy, were used in the pre- and post-test. The intervention's effectiveness was analysed via percentages for binary responses and paired t-tests for normally distributed responses. The generalised estimation equation model (GEE) ensured its effectiveness on the outcomes. RESULTS: The intervention significantly improved HL awareness, self-efficacy, and overall health literacy, including four dimensions (access, understanding, appraising, and applying health information) across three health domains (health care, disease prevention, and health promotion). Furthermore, the intervention significantly led to the intention to take health-promoting action and its five constructs. GEE analysis confirmed the intervention's effectiveness in terms of self-efficacy, health-promoting actions, and health literacy (p < 0.001), excluding exercise behaviour (p > 0.05). CONCLUSION: The study revealed that a multicomponent intervention improves adolescent health literacy and health-promoting actions. This study suggests that adolescent health literacy can be enhanced by empowering teachers, parents, and schools through multilevel interventions.