Peer-reviewed article
Differential influences of early growth and social factors on young children's cognitive performance in four low-and-middle-income birth cohorts (Brazil, Guatemala, Philippines, and South Africa)
Linda Richter, Frederick Mark Orkin, Linda S. Adair, Maria Fernanda Kroker-Lobos, Nanette L. Mayol et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study examined what shapes young children's cognitive development in Brazil, Guatemala, Philippines, and South Africa by following 2,448 children from birth to 4-8.5 years old. Researchers found that parental education and family economic resources were much more important for children's thinking skills than birth weight or early growth alone. Social and economic factors accounted for over 93% of the differences in cognitive performance, while biological factors like birth weight mattered far less. The findings suggest that improving children's thinking abilities requires helping parents get better education and improve their economic situation, not just addressing nutrition.
Key points
- Parental capacity (education) accounts for 64% of total effects on cognitive performance, making it the strongest determinant
- Household resources (crowding, dependency) account for 29% of effects on cognition and 60% of effects on height at 2 years
- Social factors combined account for 93.4% of the influence on cognitive functioning, while biological factors (birth endowment, maternal height) are largely insignificant
- Birth endowment (maternal age, birth order) contributes 34% to birth weight but only 7% to childhood cognitive performance
- The same determinants show different relative strengths across the pathway from birth weight to early growth to cognitive outcomes
Limitations
The study is observational and uses structural equation modelling, which cannot prove causation. The findings describe associations in these four specific cohorts and may not generalise to all low- and middle-income settings or higher-income countries.
Abstract
BACKGROUND: Studies relating childhood cognitive development to poor linear growth seldom take adequate account of social conditions related to both, leading to a focus on nutrition interventions. We aimed to assess the roles of both biological and social conditions in determining early childhood cognition, mediated by birthweight and early linear growth. METHODS: After exploratory structural equation modelling to identify determining factors, we tested direct and indirect paths to cognitive performance through birthweight and child height-for-age at 2 years, assessed between 4 and 8.5 years of age among 2448 children in four birth cohort studies in low-and-middle-income countries (Brazil, Guatemala, Philippines and South Africa). Determinants were compared across the cohorts. FINDINGS: Three factors yielded excellent fit, comprising birth endowment (primarily maternal age and birth order), household resources (crowding, dependency) and parental capacity (parental education). We estimated their strength together with maternal height in determining cognitive performance. Percentage shares of total effects of the four determinants show a marked transition from mainly biological determinants of birth weight (birth endowment 34%) and maternal height (30%) compared to household resources (25%) and parental capacity (11%), through largely economic determinants of height at 2 years (household resources (60%) to cognitive performance being predominantly determined by parental capacity (64%) followed by household resources (29%). The largely biological factor, birth endowment (maternal age and birth order) contributed only 7% to childhood cognitive performance and maternal height was insignificant. In summary, the combined share of social total effects (household resources and parental capacity) rises from 36∙2% on birth weight, to 78∙2% on height for age at 24 m, and 93∙4% on cognitive functioning. INTERPRETATION: Across four low- and middle-income contexts, cognition in childhood is influenced more by the parental capacity of families and their economic resources than by birth weight and early linear growth. Improving children's cognitive functioning requires multi-sectoral interventions to improve parental education and enhance their economic wellbeing, interventions that are known to improve also early childhood growth.