„Comparing OECD PISA 2006 and 2015 in science performance, equity indicators showed a significant deterioration. Of three main determinants of inequalities reviewed in a recent study — low educational level of parents, unemployment or receipt of social assistance — the latter has the greatest impact on the education outcomes of children. Foreign-born students not only leave education more often, they also tend to repeat grades.“
EU-Kommission (Hrsg.), Education and Training Monitor 2018 (2018), S. 95.