„Socio-economic background has a strong influence on educational outcomes. In the latest round of the OECD Programme for International Student Assessment (PISA) survey conducted in 2022, students with a higher socio-economic background – as measured by the PISA index of Economic, Social and Cultural Status (ESCS) – performed better than their more disadvantaged peers in all countries.“
OECD (Hrsg.), To Have and Have Not – How to Bridge the Gap in Opportunities (2025), S. 124.