"An Organization for Economic Cooperation and Development (OECD) study across approximately 30 countries found that teens who said they most often read paper books scored considerably higher on a 2018 reading test taken by 15-year-olds compared to teens who said they rarely or never read books. Even among students of similar socioeconomic backgrounds, those who read books in a paper format scored a whopping 49 points higher on the Program for International Student Assessment, known as PISA. That’s equal to almost 2.5 years of learning. By comparison, students who tended to read books more often on digital devices scored only 15 points higher than students who rarely read  – a difference of less than a year’s worth of learning." (from KQED).

Ikeda, M. and G. Rech (2022), "Does the digital world open up an increasing divide in access to print books?", PISA in Focus, No. 118, OECD Publishing, Paris, https://doi.org/10.1787/54f9d8f7-en.