The impact of an experimental nutritional intervention in childhood on education among Guatemalan adults:

"Studies have shown that malnourished children in developing countries score lower on tests of cognitive function and fail to acquire fine motor skills at the normal rate. Do the effects of nourishment—good or bad—in early childhood linger into adolescence and adulthood, or do they fade away after a few years? This paper provides new evidence of the effects of early childhood nutritional interventions on adult outcomes, using longitudinal data and methods well suited to address the concerns that have been raised about earlier studies." from Textmalnutrition, Children, Education, Nutrition,

The Impact of Nutrition during Early Childhood on Education among Guatemalan Adults

Early childhood nutrition is thought to have important effects on education, broadly defined to include various forms of learning. We advance beyond previous literature on the effect of early childhood nutrition on education in developing countries by using unique longitudinal data begun during a nutritional experiment during early childhood with educational outcomes measured in adulthood. Estimating an intent-to-treat model capturing the effect of exposure to the intervention from birth to 36 months, our results indicate significantly positive, and fairly substantial, effects of the randomized nutrition intervention a quarter century after it ended: increased grade attainment by women (1.2 grades) via increased likelihood of completing primary school and some secondary school; speedier grade progression by women; a one-quarter SD increase in a test of reading comprehension with positive effects found for both women and men; and a one-quarter SD increase on nonverbal cognitive tests scores. There is little evidence of heterogeneous impacts with the exception being that exposure to the intervention had a larger effect on grade attainment and reading comprehension scores for females in wealthier households. The findings are robust to an array of alternative estimators of the standard errors and controls for sample attrition.education, schooling, Guatemala, nutrition, economic development, Latin America

What determines adult cognitive skills?: Impacts of preschooling, schooling, and post-schooling experiences in Guatemala

"Most investigations into the importance and determinants of adult cognitive skills assume that (1) they are produced primarily by schooling, and (2) schooling is statistically predetermined or exogenous. This study uses longitudinal data collected in Guatemala over 35 years to investigate production functions for adult cognitive skills—that is, reading-comprehension skills and nonverbal cognitive skills—as being dependent on behaviorally determined preschooling, schooling, and post-schooling experiences. We use an indicator of whether the child was stunted (child height-for-age Z-scoreHuman capital, cognitive skills, Stunting, work experience, Development, Education, Gender, Health and nutrition,

The Impact of Nutrition during Early Childhood on Education among Guatemalan Adults

Early childhood nutrition is thought to have important effects on education, broadly defined to include various forms of learning. We advance beyond previous literature on the effect of early childhood nutrition on education in developing countries by using unique longitudinal data begun during a nutritional experiment during early childhood with educational outcomes measured in adulthood. Estimating an intent-to-treat model capturing the effect of exposure to the intervention from birth to 36 months, our results indicate significantly positive, and fairly substantial, effects of the randomized nutrition intervention a quarter century after it ended: increased grade attainment by women (1.2 grades) via increased likelihood of completing primary school and some secondary school; speedier grade progression by women; a one-quarter SD increase in a test of reading comprehension with positive effects found for both women and men; and a one-quarter SD increase on nonverbal cognitive tests scores. There is little evidence of heterogeneous impacts with the exception being that exposure to the intervention had a larger effect on grade attainment and reading comprehension scores for females in wealthier households. The findings are robust to an array of alternative estimators of the standard errors and controls for sample attrition

What Determines Adult Cognitive Skills? Impacts of Pre-Schooling, Schooling and Post-Schooling Experiences in Guatemala

Most investigations of the importance of and the determinants of adult cognitive skills assume that (a) they are produced primarily by schooling and (b) schooling is statistically predetermined. But these assumptions may lead to misleading inferences about impacts of schooling and of pre-schooling and post-schooling experiences on adult cognitive skills. This study uses an unusually rich longitudinal data set collected over 35 years in Guatemala to investigate production functions for adult (i) reading-comprehension and (ii) non-verbal cognitive skills as dependent on behaviorally-determined pre-schooling, schooling and post-schooling experiences. Major results are: (1) Schooling has significant and substantial impact on adult reading comprehension (but not on adult non-verbal cognitive skills) —but estimates of this impact are biased upwards substantially if there is not control for behavioral determinants of schooling in the presence of persistent unobserved factors such as genetic endowments and/or if family background factors that appear to be correlated with genetic endowments are included among the first-stage instruments. (2) Both pre-schooling and post-schooling experiences have substantial significant impacts on one or both of the adult cognitive skill measures that tend to be underestimated if these pre- and post-schooling experiences are treated as statistically predetermined—in contrast to the upward bias for schooling, which suggests that the underlying physical and job-related components of genetic endowments are negatively correlated with those for cognitive skills. (3) The failure in most studies to incorporate pre- and post-schooling experiences in the analysis of adult cognitive skills or outcomes affected by adult skills is likely to lead to misleading over-emphasis on schooling relative to these pre-and post-schooling experiences. (4) Gender differences in the coefficients of the adult cognitive skills production functions are not significant, suggesting that most of the fairly substantial differences in adult cognitive skills favoring males on average originate from gender differences in completed grades of schooling and in experience in skilled jobs favoring males. These four sets of findings are of substantial interest in themselves. But they also have important implications for broader literatures, pointing to limitations in the cross-country growth literature of using schooling of adults to represent human capital, supporting hypotheses about the importance of childhood nutrition and work complexity in explaining the “Flynn effect” of substantial increases in measured cognitive skills over time, and questioning the interpretation of studies that report productivity impacts of cognitive skills without controlling for the endogeneity of such skills

What Determines Adult Cognitive Skills? Influences of Pre-Schooling, Schooling, and Post-Schooling Experiences in Guatemala

Most empirical investigations of the effects of cognitive skills assume that they are produced by schooling, and that schooling is exogenous. Drawing on a rich longitudinal data set to estimate production functions for adult reading-comprehension cognitive skills and adult nonverbal cognitive skills, we find that (1) Schooling attainment has a significant and substantial effect on adult reading-comprehension cognitive skills but not on adult nonverbal cognitive skills; and (2) Pre-schooling and post-schooling experiences have substantial positive significant effects on adult cognitive skills. Pre-schooling experiences that increase height for age at age six years substantially and significantly increase adult reading-comprehension and nonverbal cognitive skills, even after controlling for schooling attainment and post-school skilled job tenure. Post-schooling tenure in skilled jobs also has a significant positive effect on adult reading-comprehension and nonverbal cognitive skills, although the latter estimate is sensitive to how we treat gender. Age also has significant positive effect but with diminishing returns on adult reading-comprehension cognitive skills. The findings (1) reinforce the importance of early life investments; (2) support the importance of childhood nutrition (“Flynn effect”) and work complexity in explaining increases in cognitive skills; (3) question interpretations of studies reporting productivity impacts of cognitive skills without controlling for endogeneity; and (4) point to limitations in using adult schooling alone to represent human capital

Comparative models of biological and social pathways to predict child growth through age 2 years from birth cohorts in Brazil, India, the Philippines, and South Africa

Background: Early growth faltering accounts for one-third of child deaths, and adversely impacts the health and human capital of surviving children. Social as well as biological factors contribute to growth faltering, but their relative strength and interrelations in different contexts have not been fully described. Objective: The aim of this study was to use structural equation modelling to explore social and biological multidetermination of child height at age 2 y in longitudinal data from 4 birth cohort studies in low- and middle-income countries. Methods: We analyzed data from 13,824 participants in birth cohort studies in Brazil, India, the Philippines, and South Africa. We used exploratory structural equation models, with height-for-age at 24 mo as the outcome to derive factors, and path analysis to estimate relations among a wide set of social and biological variables common to the 4 sites. Results: The prevalence of stunting at 24 mo ranged from 14.0% in Brazil to 67.7% in the Philippines. Maternal height and birthweight were strongly predictive of height-for-age at 24 mo in all 4 sites (all P values <0.001). Three social-environmental factors, which we characterized as “child circumstances,” “family socioeconomic status,” and “community facilities,” were identified in all sites. Each social-environmental factor was also strongly predictive of height-for-age at 24 mo (all P values <0.001), with some relations partly mediated through birthweight. The biological pathways accounted for 59% of the total explained variance and the social-environmental pathways accounted for 41%. The resulting path coefficients were broadly similar across the 4 sites. Conclusions: Early child growth faltering is determined by both biological and social factors. Maternal height, itself a marker of intergenerational deprivation, strongly influences child height at 2 y, including indirect effects through birthweight and social factors. However, concurrent social factors, many of which are modifiable, directly and indirectly contribute to child growth. This study highlights opportunities for interventions that address both biological and social determinants over the long and short term

Height-for-age z scores increase despite increasing height deficits among children in 5 developing countries

Background: Growth failure remains a persistent challenge in many countries, and understanding child growth patterns is critical to the development of appropriate interventions and their evaluation. The interpretation of changes in mean height-for-age z scores (HAZs) over time to define catch-up growth has been a subject of debate. Most studies of child growth have been cross-sectional or have focused on children through age 5 y

Size at Birth, Weight Gain in Infancy and Childhood, and Adult Diabetes Risk in Five Low-or Middle-Income Country Birth Cohorts

OBJECTIVEdWe examined associations of birth weight and weight gain in infancy and early childhood with type 2 diabetes (DM) risk in five cohorts from low-and middle-income countries. RESEARCH DESIGN AND METHODSdParticipants were 6,511 young adults from Brazil, Guatemala, India, the Philippines, and South Africa. Exposures were weight at birth, at 24 and 48 months, and adult weight, and conditional weight gain (CWG, deviation from expected weight gain) between these ages. Outcomes were adult fasting glucose, impaired fasting glucose or DM (IFG/DM), and insulin resistance homeostasis model assessment (IR-HOMA, three cohorts). RESULTSdBirth weight was inversely associated with adult glucose and risk of IFG/DM (odds ratio 0.91[95% CI 0.84-0.99] per SD). Weight at 24 and 48 months and CWG 0-24 and 24-48 months were unrelated to glucose and IFG/DM; however, CWG 48 months-adulthood was positively related to IFG/DM (1.32 [1.22-1.43] per SD). After adjusting for adult waist circumference, birth weight, weight at 24 and 48 months and CWG 0-24 months were inversely associated with glucose and IFG/DM. Birth weight was unrelated to IR-HOMA, whereas greater CWG at 0-24 and 24-48 months and 48 months-adulthood predicted higher IR-HOMA (all P , 0.001). After adjusting for adult waist circumference, birth weight was inversely related to IR-HOMA. CONCLUSIONSdLower birth weight and accelerated weight gain after 48 months are risk factors for adult glucose intolerance. Accelerated weight gain between 0 and 24 months did not predict glucose intolerance but did predict higher insulin resistance. 35:72-79, 2012 Diabetes Car