A mixed-methods study of the drivers of stunting reduction among children under five in Nigeria, 2008-2018

Although stunting reduction at the national level in Nigeria has been modest in recent decades, especially considering the country's rapid economic growth, there is much subnational variation.

The objective of this study was to identify the factors associated with declining stunting prevalence in those states in Nigeria where the most progress was made between 2008 and 2018.

This mixed-methods study included quantitative analysis of household survey data using regression-based Oaxaca-Blinder decomposition analysis to identify factors associated with a change in mean height-for-age z-score (HAZ) over time; deductive thematic analysis of qualitative data collected through key informant interviews and focus group discussions; and policy and program review.

Improvement in child linear growth over the past decade is evident in exemplar states in both the north and south of Nigeria, driven largely by the same factors. Our modeling predicted 66% of the observed +0.25 increase in mean HAZ over time in exemplar states, with nearly 60% of the predicted increase associated with improvements in non-health sector factors: parental education (43%), household wealth (8%), and household sanitation (3%). Malaria prevention was associated with an additional 29% of the predicted HAZ change. Qualitative participants highlighted insecurity, poverty, and lower education levels in some parts of the country as barriers to improving child health and nutritional status, along with insufficient human resources for health despite an increase in the number of healthcare facilities in the country. Participants identified a range of policies and programs across multiple sectors as having likely contributed to the decline in stunting prevalence.

A multisectoral approach to stunting reduction in Nigeria appears to have been key, with progress having been driven by both the health sector and, especially, non-health sector action.