Venue: The Fuqua School of Business, Duke University, 1 Towerview Drive, Durham, NC 27708-0120
Presentation
The Causal Effect of Early Childhood Health on Cognition in Older Children in Bangladesh
The health and nutrition of young children is of importance not only for the immediate improvement in their well-being but also because of the longer-term impacts on children's physical and cognitive development. It is believed that improvements in cognition may lead to improved educational achievements and labor market opportunities which in turn can break the chain of intergenerational transmission of poverty. This paper seeks to evaluate the causal impact of important early childhood health interventions (e.g. vaccinations) on the cognition of those same children when the reach the ages 6-19 years in Matlab, Bangladesh. Depending on the model we find a modest but important 5 to 10 percent improvement in cognition among children who received health benefits early in their lives.
Our identification strategy takes advantage of the quasi-random placement of children's health interventions in a treatment and comparison area in the 1980s. We also benefit greatly from the unique secondary data sources available including pre-intervention census and health and demographic surveillance data that tacks births, deaths, vaccinations, migration etc. This allows us to show that the treatment and comparison areas are similar. We use a double-difference estimator to determine the intent-to-treat effect. We also exploit the rich secondary data and use a mother's fixed-effect instrumental variables model to examine the effect of treatment on the treated. We check for heterogeneity with respect to gender and pre-intervention wealth of the family but find little differences. In addition, we examine if sibling competition leads to changes in the outcome.
Cognitive development is measured using the Mini Mental State Exam (MMSE) on a sample of 4311 people aged 6 to 29 years with approximately half (2042) from the comparison area. The MMSE examines five areas of cognitive functioning: orientation, attention-concentration, registration, recall, and language. The original US MMSE test is typically used to assess the cognitive status of geriatric patients. However, research has shown that an MMSE, which was adapted for children, is effective at evaluating the cognitive development of children as young as 3 years.
The literature on the causal relationship between early childhood health and future human capital outcomes from quasi-random or randomized experiments is sparse, and those on cognitive development, especially of older children, is rare in developing countries. At present, such research is difficult due to the lack of detailed, longitudinal data from well-designed programs that took place 10 or more years ago (Miguel, 2005). Yet, theories of human capital development and reduction of inter-generational transmission of poverty rely on this link. Thus, this paper seeks to addresses an important gap in the literature by rigorously evaluating these prevailing theories.