Abstract
BACKGROUND: The digital divide limits rural residents' access to health information, and the potential of utilizing non healthy but culturally relevant digital resources to enhance health literacy is not yet clear. METHODS: We conducted a cross-sectional survey of 1,457 adults across 32 traditional villages in Chongqing, China. Intangible cultural heritage digital-resource use and health literacy were assessed using validated scales. Associations were examined using quantile regression, adjusted for sociodemographic, digital-infrastructure and health-status covariates. Mediation analysis and E-value tests were performed to probe mechanisms and assess robustness. RESULTS: Higher use of digital resources of intangible cultural heritage was significantly related to higher health literacy scores, and this correlation existed in all subgroups. However, the strength of this association increased progressively along the health literacy distribution: it was strongest at the 90th percentile (β = 2.49, 95% CI: 1.98-3.00) and weakest at the 10th percentile (β = 1.38, 95% CI: 0.95-1.81), supporting the cumulative advantage hypothesis. This association was more pronounced in low-bandwidth network villages (interaction p = 0.038 at the 10th percentile) and in the older population (≥ 60 years) (interaction p = 0.007 at the 10th percentile). Mediation analysis revealed that digital self-efficacy explained 31.7% of the total association between ICH use and health literacy, with significantly stronger mediation effects in older adults (45.2%) and low-bandwidth villages (38.5%). The E value for the main association (high frequency use of intangible cultural heritage reduces the risk of inadequate health literacy) was 3.24, indicating that the results are moderately robust to unmeasured confounders. CONCLUSION: The association between intangible cultural heritage digital resource use and health literacy exhibits a cumulative advantage pattern, strengthening progressively across the health literacy distribution. This association is particularly pronounced in low-bandwidth villages and among older adults, with digital self-efficacy mediating approximately one-third of the total effect. These findings highlight a culturally grounded pathway to promote health equity through targeted digital inclusion strategies.