Interactive Effects of Health Expenditure and Income Inequality on Under-five Mortality in Sub-Saharan Africa

This study examines the interactive effects of health expenditure and income inequality on under-five mortality in Sub-Saharan Africa from 2000 to 2023 using a Generalized Method of Moments (GMM) approach. Utilizing panel data from the World Bank (2025), child mortality is measured per thousand live births, health expenditure is categorized into public and private components, and income inequality is captured via the Gini coefficient. Empirical results indicate that domestic public health expenditure has a negative but statistically insignificant direct effect on under-five mortality, whereas domestic private health expenditure shows a significant negative effect. Conversely, income inequality significantly increases child mortality. Notably, the interaction between public health expenditure and income inequality is negative and statistically significant, demonstrating that equitable public healthcare financing helps mitigate the adverse health impacts of income disparities. In contrast, the interaction between private health spending and income inequality is positive and statistically significant. The study concludes that expanding equitable public health spending and addressing socio-economic inequality are essential strategies for improving child survival outcomes across the region.