Socioeconomic and Regional Disparities in Under-five Mortality in Indonesia: Insights From Indonesia’s 2020 Census

Objectives: This study examined district-level and municipality-level socioeconomic determinants of the under-five mortality rate (U5MR) to inform equitable policies aimed at achieving Sustainable Development Goal (SDG) 3.2.Methods: An ecological cross-sectional study was conducted using data from 514 districts and municipalities in Indonesia. U5MR estimates were obtained from Statistics Indonesia and calculated using the indirect Trussell method based on the 2020 Population Census Long Form. Poverty rate, mean years of schooling, gross regional domestic product per capita, and total fertility rate (TFR) were analyzed using bivariate and multivariable ordinary least squares regression with robust standard errors. To account for spatial dependence, a spatial autoregressive (SAR) model was additionally applied. Spatial mapping was used to illustrate geographic variation.Results: U5MR ranged from 10.7 to 75.8 deaths per 1000 live births across districts and municipalities. Higher TFR (β=13.21, p<0.001) and higher poverty rates (β=0.61, p<0.001) were associated with higher U5MR, whereas higher educational attainment was associated with lower U5MR (β=−0.79, p=0.001). The association between poverty and mortality was stronger in rural districts than in municipalities (interaction β=−0.30, p=0.06). The SAR model identified significant spatial dependence and demonstrated improved model fit. Spatial clustering revealed an east-west divide, with the highest mortality observed in Papua and East Nusa Tenggara.Conclusions: Fertility, poverty, and educational attainment are key predictors of child survival in Indonesia, with districts in eastern regions bearing disproportionate burdens. Policy efforts should prioritize family planning, maternal education, and targeted support for socioeconomically disadvantaged districts to accelerate progress toward achieving SDG 3.2 by 2030.