Modeling the potential impacts of improved monthly income on child stunting in India: a subnational geospatial perspective

OBJECTIVES: Approximately one-third of the world’s stunted (low height-for-age) preschool-aged children live in India. The success of interventions designed to tackle stunting appears to vary by location and depth of poverty. We developed small-area estimation models to assess the potential impact of increments in household income on stunting across the country. DESIGN: Two nationally representative cross-sectional datasets were used: India’s National Family Health Survey 4 (2015–2016) and the 68th round of the National Sample Survey on consumer expenditure. The two datasets were combined with statistical matching. Gaussian process regressions were used to perform geospatial modelling of ‘stunting’ controlling for household wealth and other covariates. SETTING AND PARTICIPANTS: The number of children in this sample totalled 259 627. Children with implausible height-for-age z-scores (HAZs) >5 or <−5, or missing data on drinking water, sanitation facility, mother’s education, or geolocation and children not residing in mainland India were excluded, resulting in 207 695 observations for analysis. RESULTS: A monthly transfer of ~$7 (500 Indian rupees) per capita to every household (not targeted or conditional) was estimated to reduce stunting nationally by 3.8 percentage points on average (95% credible interval: 0.14%–10%), but with substantial variation by state. Estimated reduction in stunting varied by wealth of households, with the poorest quintile being likely to benefit the most. CONCLUSION: Improving household income, which can be supported through cash transfers, has the potential to significantly reduce stunting in parts of India where the burdens of both stunting and poverty are high. Modelling shows that for other regions, income transfers may raise incomes and contribute to improved nutrition, but there would be a need for complementary activities for alleviating stunting. While having value for the country as a whole, impact of income gained could be variable, and underlying drivers of stunting need to be tackled through supplementary interventions.