Item variability shows no overall main effect on generalization in either experiment¶

Claim · All claims
Evidence · 1 study (2 entries) · causal r2 · q3 · i1–i2
Currency · newest study 2026 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i2 In Experiment 1, varied and repeated items groups had similar final-test accuracy (ηp² = .04, p = .076). → Meng Cao & Paulo F. Carvalho 2026 q3 i1 In Experiment 2, varied and repeated items groups again had similar final-test accuracy (ηp² = .02, p = .262). → Meng Cao & Paulo F. Carvalho 2026 (2)

Evidence¶

Meng Cao & Paulo F. Carvalho 2026¶

Meng Cao & Paulo F. Carvalho. (2026). Striking the Balance: How Variability Shapes Retrieval Practice and Worked Examples for Transfer Learning. Educational Psychology Review. https://doi.org/10.1007/s10648-026-10169-w

q3 · i2 · causal · r2

Experiment 1's mixed-effects ANOVA found no significant main effect of variability on final-test accuracy, with printed effect size ηp² = .04 ("F(1,76) = 3.24, p = .076, ηp 2 = .04"); the p-value was marginal but did not reach threshold.

"participants who practiced with varied items and those who practiced with repeated items had similar accuracy on the final test, F(1,76) = 3.24, p = .076, ηp 2 = .04."

Meng Cao & Paulo F. Carvalho 2026 (2)¶

Meng Cao & Paulo F. Carvalho. (2026). Striking the Balance: How Variability Shapes Retrieval Practice and Worked Examples for Transfer Learning. Educational Psychology Review. https://doi.org/10.1007/s10648-026-10169-w

q3 · i1 · causal · r2

Experiment 2's mixed-effects ANOVA likewise found no significant main effect of variability, with printed effect size ηp² = .02 ("F(1,72) = 1.28, p = .262, ηp 2 = .02"); variability mattered only in interaction with strategy.

"participants who practiced with varied items and those who practiced with repeated items had similar accuracy on the final test, F(1,72) = 1.28, p = .262, ηp 2 = .02."

Discussion¶

Related Claims¶

• Retrieval practice takes more learning time than worked examples, and variability slows improvement during practice — related
• Without initial instruction, varied retrieval practice matches varied worked examples and beats repeated retrieval practice for generalization — related