A Theory of Planned Behavior–Based Cluster Randomized Trial to Improve Health Literacy Among Rural Adults in China

Rural populations often face structural barriers to accessing, interpreting, and using health information, contributing to persistent health literacy disparities. This cluster randomized controlled trial evaluated whether a theory of planned behavior-based intervention could improve health literacy acquisition behaviors and overall health literacy among rural residents in Changzhou, China. Twenty villages were randomized to a 12-month multicomponent intervention or routine health education. The intervention targeted behavioral attitude, subjective norms, and perceived behavioral control through health information materials, WeChat-based messaging, interactive lectures, peer discussion, and practical training in health information seeking and appraisal. Outcomes were assessed at baseline and 12 months using the Short-Form Health Literacy Scale and theory of planned behavior-based measures. Linear mixed-effects models accounting for clustering and repeated measurement showed significant intervention effects on behavioral attitude, subjective norms, behavioral intention, health literacy acquisition behavior, and overall health literacy, but not perceived behavioral control. Results were consistent in intention-to-treat, per-protocol, and generalized estimating equation sensitivity analyses. These findings suggest that theory-informed behavioral strategies can strengthen health literacy-related motivation and practices in rural communities, although additional structural support may be needed to improve perceived control over health information access and use.