Peer-reviewed article

Effects of responsive caregiving and learning opportunities during pre-school ages on the association of early adversities and adolescent human capital: an analysis of birth cohorts in two middle-income countries

Angela C. B. Trude, Linda Richter, Jere Richard Behrman, Aryeh D. Stein, Ana Maria Baptista Menezes et al. · 17 Dec 2020

Summary

Written by AI, not yet AICS's view · claude-haiku-4-5-20251001

This study examined whether responsive caregiving and learning opportunities in early childhood could protect children from the negative effects of early adversities on later development. Using data from birth cohorts in Brazil and South Africa, researchers followed children from age 2-4 years to adolescence (ages 14-18). They found that a nurturing home environment with good learning opportunities and responsive caregiving significantly reduced the impact of early hardships like poverty and poor maternal health on adolescent intelligence and development.

Key points

Each additional unit of cumulative early adversity (poverty, crowding, poor maternal health, low birthweight) was associated with a 2.7 to 5.9 point decrease in adolescent IQ across the two cohorts
In Brazil's 1993 Pelotas cohort, each additional unit of learning opportunities increased adolescent IQ by 5.47 points; responsive caregiving increased it by 2.26 points
High nurturing home environments modified (reduced) the negative association between early adversities and adolescent IQ in both cohorts
The protective effect of nurturing care was stronger in Brazil (learning opportunities effect) and South Africa (responsive caregiving effect)
Benefits persisted from early childhood (ages 2-4) through adolescence (ages 14-18), showing long-term cognitive gains

Limitations

The study measured nurturing care at only one time point in early childhood and cannot determine if timing, intensity, or duration of nurturing care matters. Unmeasured confounding factors that influence both home environment quality and child outcomes cannot be ruled out.

Abstract

BACKGROUND: Millions of children globally are at risk of not reaching their developmental potential because of early adversities. We hypothesised that responsive caregiving and learning opportunities, components of nurturing care, at pre-school ages might mitigate the effects of adversities. METHODS: We analysed longitudinal birth cohort data from Brazil (1993 Pelotas Birth Cohort, n=632) and South Africa (Birth to Twenty Plus [Bt20+] Birth Cohort, n=1130) to assess whether responsive caregiving and learning opportunities at pre-school ages (2-4 years) modified associations between cumulative early adversities and adolescent human capital. The cumulative adversities score (range 0-9) included household wealth and crowding; mothers' schooling, height, age, and mental health; and children's birthweight, gestational age, and length at age 12 months. We extracted data on responsive caregiving and learning opportunities from the Early Childhood Home Observation for Measurement of the Environment inventory, assessed at age 4 years (1993 Pelotas cohort) and 2 years (Bt20+ cohort). We examined three human capital indicators: intelligence quotient (IQ) assessed at age 18 years (1993 Pelotas cohort) and 16 years (Bt20+ cohort); psychosocial adjustment assessed at age 15 years and 14 years, respectively; and height assessed at age 18 years and 16 years, respectively. We used linear models with interaction terms between cumulative adversities, and responsive caregiving and learning opportunities, to predict adolescent human capital. FINDINGS: For each additional Z score of total cumulative adversity, adolescent IQ decreased by 5·89 (95% CI -7·29 to -4·50) points in the 1993 Pelotas cohort (p<0·0001) and 2·69 (-4·52 to -0·86) points in the Bt20+ cohort (p=0·0039). After adjusting for total cumulative adversities, adolescent IQ points increased by 5·47 (95% CI 4·20 to 6·74) with each additional Z score of learning opportunities and by 2·26 (0·93 to 3·59) with each additional Z score of responsive caregiving in the 1993 Pelotas cohort, but not in the Bt20+ cohort (0·86 [-0·12 to 1·83] and 0·65 [-0·32 to 1·61], respectively). Associations between early adversities and IQ were modified by learning opportunities in the 1993 Pelotas cohort (beta coefficient for interaction 1·74, 95% CI 0·43 to 3·04; p=0·0092) and by responsive caregiving in the Bt20+ cohort (2·24, 0·94 to 3·54; p=0·0075). High nurturing environment attenuated the negative effects of early cumulative adversities on IQ. INTERPRETATION: Early nurturing home environments protect young children against effects of early adversities on adolescent IQ, with long-term positive associations on adolescent cognition in two middle-income countries. FUNDING: Bill & Melinda Gates Foundation.

Findings the Hub has extracted

Each claim below is labelled by its type of design and links back to this report.

Development

BRZA

Problem

Early adversities such as poverty, poor maternal health, and low birthweight impair children's cognitive development and long-term human capital

Intervention: Responsive caregiving and learning opportunities provided in the home environment during pre-school ages (2-4 years)
Population: Children in two birth cohorts: 632 from Brazil (1993 Pelotas cohort) and 1,130 from South Africa (Birth to Twenty Plus cohort), followed from early childhood to adolescence

Key finding

Each additional Z score of cumulative adversity decreased adolescent IQ by 5.89 points (Brazil) and 2.69 points (South Africa)

Experimental