„An alarming result from the most recent 2018 Programme for International Student Assessment (PISA) shows the reading performance gap between the 10 % most socioeconomically disadvantaged and the 10 % least socioeconomically disadvantaged students in France, Hungary, Israel, Peru, and the Slovak Republic is about four years of schooling.“
OECD (Hrsg.), Teaching as a Knowledge Profession (2021), S. 68.