Brief signed video lessons produced learning gains, but the study could not rule out practice effects because it lacked a no-training control group¶

Claim · All claims
Evidence · 1 study · causal r2 · q1
Currency · newest study 2026 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q1 i? The authors state that gains from pre-test to post-test could partly be attributed to taking the test twice rather than to the videos, since no no-training control group was included. → Rachel Sortino 2026

Evidence¶

Rachel Sortino 2026¶

Rachel Sortino, Christina Kim, Thalia Guettler, Katie McClyman, Lorna Quandt, Alicia Wooten & Rachel Pizzie. (2026). Producing concept-motivated signs supports learning of STEM content in American Sign Language. npj Science of Learning 11:37. https://doi.org/10.1038/s41539-026-00418-6

q1 · i? · causal · r2

This is the authors' stated limitation, not a tested result. They note randomized question order, alternative question versions, and non-repeated measures (matching task, signed summaries) were used to reduce practice effects.

"We did not incorporate a no-training control group to rule out the possibility of improvements in test scores coming from test-retest effects, which means the gains we saw from pre-test to post-test could be attributed to learning from taking the test twice in the same day instead of from the videos themselves."

Discussion¶

Related Claims¶

• Longer and more accurate signed summaries predicted higher post-test scores only for concept-motivated lessons, not English-motivated lessons — related
• Learning from concept-motivated versus English-motivated ASL lessons showed no significant difference in pre-to-post score gains — a narrower finding that bears on this claim
• Adult ASL-fluent participants significantly improved STEM test scores by about 22% after watching four-to-six-minute ASL video lessons — possibly the same claim (merge candidate)
• Producing more concept-motivated signs in signed summaries predicted higher test scores, especially post-test, while English-motivated sign use did not — related