The impact of demographic characteristics on health literacy in the population: a mixed model analysis based on panel survey data from China

Background: Health literacy is strongly correlated with health outcomes, making it a key indicator of population health. This study aimed to analyze trends in health literacy and assess the impact of key demographic factors on these trends in Shandong Province, China, to inform future health education strategies. Methods: A cross-sectional study analyzed 12,302 samples from 2012, 2016, and 2020, employing mixed-effects models to investigate trends in health literacy and influencing factors in Shandong Province, China. Results: This study examined health literacy determinants using data from 12,302 participants in Shandong Province across three waves (2012, 2016, 2020). The analysis revealed substantial age-related disparities, with health literacy prevalence declining from 17.6% among adults aged 25–34 to 9.2% in the 55–64 age group. Urban residents demonstrated significantly higher health literacy rates than rural counterparts (17.5% vs. 8.9%). Mixed-effects models showed each increasing education level was associated with 60% higher odds of health literacy (OR = 1.60, 95% CI: 1.51–1.69), though this effect diminished over time (2012 coefficient: 0.615; 2020 coefficient: 0.365). Urban residence was associated with 39% lower odds of limited health literacy (OR = 0.61, 95% CI: 0.54–0.69). The relationship between self-rated health and health literacy shifted significantly, with coefficients changing from 0.050 (2012) to -0.155 (2020), indicating strengthening protective effects. Conclusions: Despite progress, significant health literacy challenges persist in Shandong Province, characterized by evolving media dynamics, persistent urban-rural disparities, and the changing role of education. These findings call for targeted interventions focusing on high-risk groups such as the older population, bridging the urban-rural gap through improved digital health resource allocation in rural areas, and integrating health literacy into educational systems to ensure sustainable impact. Addressing these priorities is essential for fostering health literacy and achieving a healthier population.