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

This study investigates the interactive effects of health expenditure and income inequality on under-five mortality in Sub-Saharan Africa from 2000 to 2023 using a panel GMM approach. The persistent high rate of under-five mortality in the region remains a major public health concern despite global efforts to improve child survival outcomes. The study adopts a panel data framework, drawing on secondary data sourced from the World Bank (2024). Health expenditure was measured by public health expenditure and private health expenditure, the Gini coefficient is used as a measure of income inequality, and the dependent variable, which is under-five mortality, was measured as one per thousand live births. The result from the study shows that domestic public health expenditure was found to have a negative and statistically insignificant effect on under-five mortality. This implies that public health expenditure alone does not exert a significant influence on under-five mortality in the sampled countries within the study period. Conversely, domestic private health expenditure exhibited a negative and statistically significant relationship with under-five mortality, while Income inequality showed a positive and statistically significant effect on under-five mortality, indicating that wider disparities between the rich and poor worsen child health outcomes. Furthermore, the interaction between domestic public health expenditure and income inequality was negative and statistically significant, suggesting that increased public health expenditure mitigates the adverse effect of income inequality on under-five mortality. In contrast, the interaction between domestic private health expenditure and income inequality was positive and statistically significant, indicating that reliance on private healthcare financing in highly unequal societies may aggravate child mortality by limiting healthcare access among poorer households. The study concluded that equitable public healthcare financing plays a critical role in reducing under-five mortality and cushioning the harmful effects of income inequality in Sub-Saharan Africa. The study therefore recommended increased government allocation to the health sector, expansion of universal healthcare coverage, and the implementation of inclusive socio-economic policies aimed at reducing income inequality and improving access to quality healthcare services among vulnerable populations.