Projecting National Outpatient Health Expenditures Under Health Literacy Improvement Scenarios: A Simulation Study

BackgroundSouth Korea's Health Plan 2030 targets an increase in the proportion of adults with sufficient health literacy to 70% by 2030.MethodsThis scenario-based simulation study projected national outpatient healthcare expenditure from 2023 to 2030 using an ARIMA(1,1,1) model fitted to Korea National Health Accounts data (1970-2022). Two scenarios were compared: status quo (no change in health literacy distribution) and policy target (linear increase in sufficient health literacy from 49.3% in 2021 to 70% by 2030). An 8.6% expenditure differential between health literacy groups (95% CI: 1.3%-15.4%), estimated from the 2021 Korea Health Panel Survey, was applied with sensitivity analyses.ResultsNational outpatient expenditure was projected to reach KRW 91.2 trillion by 2030 under the status quo, compared with KRW 89.5 trillion under the policy target scenario, representing savings of KRW 1.70 trillion (1.9%). Sensitivity analyses yielded projected savings of KRW 0.25-3.15 trillion.ConclusionThese projections are conditional on modeling assumptions and do not imply causality, but suggest that achieving the national health literacy target may contribute to reducing outpatient expenditure and improving healthcare system efficiency.