Analysis Group Expert Publishes Study on the Impact of Birth Order on Early Childhood Cognitive Abilities and Parental Behavior

February 22, 2017

A growing number of studies find that latter-born children have lower education and labor market outcomes as adults compared to those of their older siblings, a phenomenon known as the “birth order effect.” In a recent study “The Early Origins of Birth Order Differences in Children's Outcomes and Parental Behavior,” published in the Journal of Human Resources, Analysis Group Manager Jee-Yeon Lehmann and her coauthors find that birth order differences in cognitive assessments appear very early. Using data from 5,000 children who completed developmental and standardized cognitive tests every two years from birth to age 14, the study finds that, as early as age one, latter-born children score lower on these assessments and the birth order gap in cognitive abilities increases until school entry and remains substantial thereafter. Examining parental behavior, the authors find that parents provide lower levels of cognitive stimulation at home for latter-born children and mothers are less likely to breastfeed, seek timely prenatal care, and reduce smoking with subsequent pregnancies. These variations in parental behavior can explain most of the birth order difference in cognitive test scores before school entry, suggesting that a plausible explanation for the birth order effect is a broad shift in parenting, especially with respect to parents' ability to foster early cognitive development.

Read the study here

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