Peer-Reviewed Study

International Declines in Academic Performance and Increases in Loneliness Are Linked to Electronic Devices

Jan 2026 🌐 Journal of Adolescence Ages 15–16 PEER-REVIEWED PAYWALLED — LINKED, NOT HOSTED

Published in the Journal of Adolescence, this sole-authored Jean Twenge study uses the OECD's Program for International Student Assessment (PISA), which surveys 15- and 16-year-olds in dozens of countries every three years, to look for international patterns behind rising adolescent loneliness and falling standardized-test scores. Drawing on PISA rounds from 2000–2022 (over 1.7 million students across 36 countries), Twenge reports that in most countries, students' reported school loneliness rose while math, reading, and science scores fell, both shifts most pronounced between 2012 and 2022. Countries where adolescent smartphone access grew fastest, and where students reported more leisure device use during school hours, showed larger increases in loneliness and larger score declines. Twenge treats the cross-country pattern as evidence the trend is not explained by any single country's circumstances. TechKids Foundation cites this as her broadest-scope peer-reviewed study, extending her U.S.-focused argument to a global dataset.

n = 1,788,128 15- to 16-year-old students, 36 countries

PISA survey rounds from 2000 to 2022 (2022 round delayed a year due to COVID-19), roughly evenly split by gender, spanning North America, Latin America, Europe, and Asia.

Loneliness up, test scores down, sharpest 2012–2022

In most participating countries, school loneliness increased and math/reading/science scores declined, with the paper describing the shifts as particularly pronounced in the 2012–2022 window.

Larger shifts where smartphone access and school-day device use grew more

Countries with bigger increases in adolescent smartphone access, and where students reported more school-day leisure device use, showed larger increases in loneliness and larger declines in academic performance, per the study's results.

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CITATION

Twenge, Jean M. "International Declines in Academic Performance and Increases in Loneliness Are Linked to Electronic Devices." Journal of Adolescence 98, no. 1 (2026): 250–261. https://doi.org/10.1002/jad.70058

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