Testing (Quizzing) Boosts Classroom Learning: A Systematic and Meta-Analytic Review
Yang, C., Luo, L., Vadillo, M. A., Yu, R., & Shanks, D. R. · 2021
grade Bmeta-analysisindependentreplicatednumbers spot-checked
Sample
222 studies / 48,478 students
Population
K-12 through higher-ed and professional; authentic classroom content and assessments.
Design
Largest CLASSROOM-only testing-effect meta. Mixed RCT + quasi designs; mostly researcher-aligned course assessments.
Key findings
Strongest classroom anchor: g=0.499 across 222 studies/48k students. Effect partly transfers to related untested material (0.32) but ~35% smaller; aligned formats inflate it (0.53 vs 0.40); quizzing barely beats active elaborative controls (big gains are vs no-activity); feedback helps. Real in classrooms but on aligned course tests.
Genetic confound
Achievement/retention outcome; no g or ability-interaction claim.
Replication notes
Numbers verified. Converges with Adesope, Rowland, Agarwal 2021.
DOI / URL
10.1037/bul0000309
Effects
| Outcome | Metric | Value | Measure | Timing | Vs | Horizon | Class |
|---|---|---|---|---|---|---|---|
| Overall achievement gain from quizzing | g | 0.499 (medium) | researcher-designed | mostly delayed course exams; classroom | business-as-usual | under-1yr | domain-skill |
| Transfer to related but UNTESTED material | g | 0.321 (~35% smaller than tested material) | researcher-designed | delayed; near-transfer | business-as-usual | under-1yr | near-transfer |
| Format-match (aligned vs mismatched) | g | aligned 0.531 vs mismatched 0.399 (measure-alignment inflation) | researcher-designed | delayed | active-alternative | under-1yr | domain-skill |
| Feedback vs no feedback | g | 0.537 vs 0.374 (feedback helps) | researcher-designed | delayed | active-alternative | under-1yr | domain-skill |
| Vs active elaborative controls (concept mapping, notes) | direction | only MINIMAL advantage — big gains are mostly vs no-activity | researcher-designed | delayed | active-alternative | under-1yr | domain-skill |
Cited by
- Retrieval practice (the testing effect)strong supportconf: highgc: low