A Semi-Parametric Analysis of Childhood Stunting in India: District Level Scenario

Abstract

BackgroundA growing body of literature has recognized the urgency of addressing the issue of childhood stunting (low height for age) in India and dedicated substantial resources to identifying the factors that are strongly associated with its considerable prevalence in the country. However, most of these studies have focused on parametric models with limited use of geographic information and prefixed assumption on the linear association of various factors with stunting outcomes. The present study re-investigates the non-linear association of certain covariates along with spatial effects by using a flexible Bayesian semi-parametric regression approach at the district level.MethodData is taken from the recent fourth round of the National Family Health Survey (NFHS 4, 2015-16). The analysis is based on the data from 2,24,190 children whose complete anthropometric measurements of weight and height are measured.ResultsThe paper has two major contributions. First, it challenges the pigeonholing of linear association of covariates. It identifies a non-linear association of child's age, mother's age at birth, and mother's BMI with childhood stunting. Children's height-for-age score worsens up to the age of 20 months and then stabilizes at a lower HAZ score in the states with a high prevalence of childhood stunting. Almost all high prevalence states display an inverted U association for maternal BMI suggesting that not just underweight mothers, but overweight mothers are also likely to have stunted children. Secondly, the results indicate high spatial clustering of poor performing districts in states with a high prevalence of childhood stunting. For example, the districts in the West of Bihar show significantly higher levels of childhood stunting than the ones in the East.ConclusionsThis is the first time that a flexible and realistic model has been applied to district-level data to identify regional variation and highlight the issues of pigeonholing linear association of all correlated of childhood stunting. The findings from the study is a novel attempt to rethink restrictive modeling approaches of various public health issues in a regionally diverse country such as India.