Aim: To examine whether the association between breastfeeding and childhood cognitive development is direct or whether the association is spurious owing to confounding variables.
Method: The current study conducted a propensity score matching (PSM) analysis using data from the Early Childhood Longitudinal Study, Birth Cohort.
Results: The results of PSM models revealed that prior to matching, the association between breastfeeding and cognitive functioning was significant (mean difference = 3.20, t-value = 7.86, 95% confidence interval (CI) = 2.40–4.00, P ≤ 0.05). After controlling for a range of confounding factors, the mean difference was reduced by 40% (mean difference = 1.92, t-value = 3.75, 95% CI = 0.92–2.93, P ≤ 0.05); however, significant differences remained between groups.
Conclusion: The results produced in the current study provide tentative evidence that breastfeeding may have an influence on the development of cognitive abilities in children. Additional research is necessary, however, in order to further evaluate the causal impact and exact developmental pathway of breastfeeding on childhood cognitive growth.