Impact of Government Health Expenditure, Environmental Quality and Medical Technology on Infant Mortality in Nigeria

This study examined the effects of government health expenditure, environmental degradation and medical technology on infant mortality rate (IMR) in Nigeria over the period 1985–2023, controlling for gross domestic product per capita and urbanization. The study was motivated by the persistent burden of infant mortality and the need to understand how health financing, environmental conditions and technological capacity are associated with infant survival. The study employed the Autoregressive Distributed Lag (ARDL) approach after the KPSS unit root test established a mixed order of integration, with the variables being either I(0) or I(1). The ARDL bounds test produced an F-statistic of 18.28348, exceeding the upper-bound critical value at the 5% significance level, providing evidence of a long-run relationship among the variables. The long-run results show that government health expenditure (LGHEX) has a negative but statistically insignificant coefficient, while environmental degradation (ENVDEG), proxied by carbon dioxide (CO₂) emissions, has a positive and significant coefficient, indicating that higher CO₂ emissions are associated with higher IMR. Medical technology (MEDTECH) has a positive but insignificant long-run coefficient, whereas urbanization significantly reduces IMR. Gross domestic product per capita (GDPPC) has a positive but insignificant long-run coefficient. In the short run, environmental degradation is positively associated with IMR, while medical technology produces significant mortality-reducing effects after several lags. The error correction coefficient of -0.189468 indicates that approximately 18.95% of short-run disequilibrium is corrected annually towards the long-run equilibrium. The study concludes that reducing IMR in Nigeria requires more efficient health expenditure, reduction of environmental degradation, strengthened medical technology and improved access to healthcare services.