1.3 Stunting as proxy for child development

Stunting is the impaired physical growth and development that children experience from poor nutrition, repeated infection, and inadequate psychosocial stimulation. Linear growth in children is commonly expressed as length-for-age or height-for-age in comparison to normative growth standards (Wit et al. 2017). According to the World Health Organization (WHO), children are stunted if their height-for-age is more than two standard deviations below the Child Growth Standards median. Stunting caused by chronic nutritional deprivation in early childhood is as an indicator of child development (Perkins et al. 2017).

There is consistent evidence for an association between stunting and poor child development, despite heterogeneity in the estimation of its magnitude (Miller et al. 2016; Sudfeld et al. 2015). Considering impaired linear growth as a proxy measure for child development is easy to do, and quite common. Yet, using impaired height growth as a measure for child development is not without limitations:

• The relation between height and child development is weak after adjustment for age;
• Height is a physical indicator that does not take into account a direct evaluation of a child’s cognitive or mental performance;
• There is considerable heterogeneity in heights of children all over the world;
• Height is not sensitive to rapid changes in child development.