An age profile perspective on two puzzles in global child health: The Indian Enigma & economic growth

We provide an age-profile perspective and two classes of regression models that make progress on differentiating between two types of determinants of child health: health endowment effects provided to the child at birth; and health investment effects determined by the post-birth stream of health inputs provided to the child and the productivity of those investments. We apply the framework to two related puzzles in the child health demography literature: the Indian Enigma, where Indian children are on average less tall than African children; and the apparent lack of strong correlation between economic growth and child height-for-age z-score (HAZ). In the context of the Indian Enigma, we find that the Indian-African child HAZ gap (between 0.3sd and 0.5sd) is present immediately after birth and maintains a similar magnitude across the first three years of life. We interpret this as evidence that causes affecting health endowments (such as maternal physiology, fertility timing or in utero nutrition) likely explain the greater part of the Indian Enigma. We also estimate a robust association between a 10% increase in (ln) GDP per capita and a 0.04sd increase in child height by age 2. However, this correlation is not present at birth and is instead driven by differences in child growth rates. We interpret these results as indicating that economic growth influences the post-birth health input stream, and/or the biological productivity of those inputs.