Learning losses increase with the length of school closures, from 9–12% SD in shortest-closure countries to 17–23% SD in longest-closure countries¶

Claim · All claims
Evidence · 1 study · associational r3 · q2
Currency · newest study 2025 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q2 i? Countries at the 90th percentile of closure length lost 17–23% of a SD, versus 9–12% of a SD for countries at the 10th percentile, across four closure measures. → Maciej Jakubowski 2025

Evidence¶

Maciej Jakubowski 2025¶

Maciej Jakubowski, Tomasz Gajderowicz & Harry Anthony Patrinos. (2025). COVID-19, school closures, and student learning outcomes. New global evidence from PISA. npj Science of Learning. https://doi.org/10.1038/s41539-025-00297-3

q2 · i? · associational · r3

Numerical regression estimates shown in Fig. 1 compare predicted losses at the 10th, 25th, 50th, 75th and 90th percentiles of four closure measures (UNESCO full and full-plus-partial; PISA student and principal reports). Countries with the longest closures "experienced losses of 17–23% SD, or 9–12 months of learning".

"First, the learning losses increase with the length of school closures. This shows that the achievement decline is associated with school closures and not only the overall impact of the pandemic on students."

Discussion¶

Learner Variables¶

• Time and Continuity — predictor: learners who differ on it differ in outcomes

Related Claims¶

• In countries with the longest closures, losses were concentrated among average and lowest-achieving students, while the best achievers lost 8–9 points everywhere — related
• Students in The Netherlands lost on average 3.16 percentile points (0.08 SD) in achievement during the 8-week COVID-19 lockdown — related
• The COVID cohort scored significantly lower than the control cohort across the whole study duration — related
• Closure-duration losses are larger for boys and immigrant students: boys' overall loss equals girls' at about 40 weeks of full closures, and immigrants' equals natives' at about 25 weeks — related
• One year or more after the first lockdown, students had not recovered the learning deficits caused by Covid-19 school closures — related
• Children from low-SES families were more negatively affected by COVID-19 school closures than children from high-SES families — related
• Covid-19 school closures depressed student achievement on average by about 0.19 standard deviations — a broader claim this one bears on