Health literacy, socioeconomic status and self-rated health in Japan

Health literacy (HL) is a key determinant of health in a contemporary society characterized by abundant information. Previous studies have suggested that basic or functional HL is positively associated with health, whereas evidences on the association between health and communicative/critical HL are scarce. Furthermore, confounding by socioeconomic status on HL-health association has been poorly tested. Using cross-sectional data from a nationally representative community-based survey in Japan, we investigated whether communicative/critical HL is associated with self-rated health independent of socioeconomic status. A total of 1237 subjects participated in this study; the response rate was 62%. To measure communicative/critical HL, we used three questions assessing the respondents' ability to select, to communicate to others and to evaluate specific health-related information. Potential confounders included demographic factors, household income, employment status, and educational attainment. A multivariate model revealed that good self-reported health was significantly associated with younger age [odds ratio (OR), 0.99; 95% confidence interval (CI), 0.97-0.99], employment (OR, 2.89; 95% CI, 1.06-7.88) and higher communicative/critical HL scores (OR 2.75; 95%CI, 1.93-3.90). Respondents with lower education were likely to have poorer communicative/critical HL. These results imply that to close the health gap, policy interventions should focus on the promotion of HL among deprived sociodemographic groups.