„Results from PISA 2015 show that students who reported that they had missed a day of school or had arrived late for school at least once in the two weeks prior to the PISA test were 38 % and 24 % more likely, respectively, to have repeated a grade than students who reported that they had not done so.“
OECD (Hrsg.), Equity and Inclusion in Education - Finding Strength through Diversity (2023), S. 273.