Impact of socioeconomic status on IQ and attention in school children in Poland, a country with relatively low socioeconomic differences

Socioeconomic inequalities affect health via multiple biological, behavioral, and social pathways. Specifically, low socioeconomic status (SES) negatively impacts children's intelligence quotient (IQ). Most data on this topic comes from high-inequality countries such as the United States. Here, we investigate the impact of SES on IQ and attention and how it might be mediated by early-childhood factors in 10- to 13-year-old children in Poland, a country with relatively low socioeconomic differences and medium incomes. Inhibitory attention was measured using a go/no-go task. We found that parental education significantly influenced IQ and attention. Low SES children scored on average 3 IQ points lower than high SES children and had significantly longer reaction times and d’ (discrimination accuracies). Family SES had a clear non-mediated impact on IQ, and an overall effect on attention. On the other hand, smoking/alcohol during pregnancy, and breastfeeding, while all correlated with SES, did not modify its effects on IQ or attention. We conclude that the impact of SES on cognition is considerable even in a low-inequality country such as Poland, and in our population it cannot be explained by these early-life factors.