Rural-urban disparities in child nutrition in Tabora, Tanzania: a socioeconomic decomposition and implications for food security policy.

Child malnutrition remains a major barrier to human capital development in sub-Saharan Africa, yet the drivers of rural-urban inequalities remain insufficiently understood. This study examines socioeconomic disparities in child health between rural and urban households in Tabora, Tanzania, using cross-sectional data from 490 households across seven districts. Employing Blinder-Oaxaca decomposition, instrumental variable (IV) estimation, and structural equation modeling (SEM), the study finds a pronounced rural-urban gap in child nutrition, with a Height-for-Age Z-score difference of -0.685, indicating significantly higher stunting prevalence in rural areas. The decomposition results show that approximately 72% of the observed gap is explained by differences in observable characteristics, with household income, nutrition intake, and drinking water practices (boiling water consumption) emerging as the most influential contributors, highlighting the central role of economic constraints and basic infrastructure deficits rather than purely behavioral differences. SEM and IV results further confirm that these factors operate through interconnected pathways affecting both objective nutrition outcomes and perceived health status, while parental education plays a comparatively limited role. Based on these findings, policy interventions should prioritize income-enhancing strategies such as rural livelihood support, targeted cash transfers, and employment programs, alongside large-scale investment in rural water infrastructure, including piped water systems, boreholes, and household water treatment solutions, given their substantial contribution to the health gap. In addition, nutrition-specific interventions such as community-based dietary education, school feeding programs, and distribution of fortified foods should be strengthened to directly address inadequate nutrition intake. These efforts should be complemented by expanded rural healthcare outreach and integrated intersectoral coordination between health, water, and economic development sectors to ensure that improvements in income, nutrition, and water access are simultaneously addressed, thereby producing sustained reductions in child health inequalities.