Our study aims to examine the disparity of under-5 child stunting prevalence between urban and rural areas of Tanzania in the past three decades, and to explore factors affecting the rural-urban disparity. Secondary analyses of Tanzania Demographic and Health Surveys (TDHS) data drawn from 1991-1992, 1996, 1999, 2004-2005, 2009-2010, and 2015-2016 surveys were conducted. Under-5 child stunting prevalence was calculated separately for rural and urban children and its decline trends were examined by chi-square tests. Descriptive analyses were used to present the individual-level, household-level, and societal-level characteristics of children, while multivariable logistic regression analyses were performed to examine determinants of stunting in rural and urban areas, respectively. Additive interaction effects were estimated between residence and other covariates. The results showed that total stunting prevalence was declining in Tanzania, but urban-rural disparity has widened since the decline was slower in the rural area. No interaction effect existed between residence and other determinants, and the urban-rural disparity was mainly caused by the discrepancy of the individual-level and household-level factors between rural and urban households. As various types of determinants exist, multisector nutritional intervention strategies are required to address the child stunting problem. Meanwhile, the intervention should focus on targeting vulnerable children, rather than implementing different policies in rural and urban areas.

Keywords: Demographic and Health Surveys; determinant; interaction; malnutrition; stunting; under-5 children.