This paper uses Propensity Score Matching to investigate the causal effect of breastfeeding on children's cognitive development. There is a strong association between breastfeeding and cognitive outcomes; however, it is notoriously difficult to establish whether this is causal, or whether it arises because mothers who breastfeed tend to be those whose children would do better anyway. Using PSM, we find that breastfeeding for four weeks has a positive and significant effect on test scores, in the order of one tenth of a standard deviation. Thus, interventions which increase breastfeeding rates may improve not only children's health, but also their cognitive skills.
Breastfeeding Cognitive Outcomes Child Development ALSPAC