Spatial analysis of under-five mortality in Africa using geographically weighted poisson regression

Abstract

Child mortality remains a significant public health challenge in developing countries despite the global decline in under-five deaths. The disparities in child mortality rates can be attributed to socioeconomic and environmental inequalities across nations. While several studies have examined geographic variations in under-five mortality in Africa using economic and health indicators, few have applied spatial analysis to characterize these patterns. This study employs Geographically Weighted Poisson Regression (GWPR) to uncover spatially varying in effects of global indicators on under-five mortality across Africa, offering a detailed understanding not captured by conventional global models. Data on under-five mortality rates and economic and health indicators were obtained from the World Bank’s World Development Indicators (WDI) for 2022 across 54 African countries. A Poisson regression model and GWPR were applied to examine the associations between under-five mortality and various socioeconomic and environmental factors. The results indicate substantial spatial heterogeneity in child mortality across countries. The GWPR model (AICc = 221.25, Pseudo R2 = 86.5%) outperformed the conventional Poisson regression model (AICc = 360.733, Pseudo R2 = 58.4%), highlighting the benefits of incorporating spatial variability. Key findings revealed that under-five mortality was positively associated with open defecation and negatively associated with literacy, health expenditure, access to electricity, and basic sanitation. Additionally, the relationship between under-five mortality, gross national expenditure, and access to basic drinking water varied across regions. These findings emphasize the need for localized, evidence-based interventions to address child mortality more effectively in Africa.