Distributed practice benefits L2 learning, and one review argues that spreading it over years can be worse than over months¶

Claim · All claims
Evidence · 2 studies · 1 quant-synthesis r?, 1 review r2 · q2–q3 · n=48 experiments (98 effect sizes, N=3,411)
Currency · newest study 2022 · 1 of 2 entries checked against their sources (automated) · not reviewed by a person

Subclaims¶

q2 i? Distributing a given amount of practice over larger stretches of time is beneficial, but there are limits: spreading practice over a couple of years may be worse than spreading it over a couple of months. → Robert DeKeyser 2010

q3 i? A meta-analysis of 48 second-language experiments found a medium-to-large spacing effect and longer spacing better than shorter spacing on delayed posttests; the abstract does not say what spacing ranges were compared, so it does not test the years-versus-months limit. → Kim and Webb 2022

Evidence¶

Robert DeKeyser 2010¶

Robert DeKeyser. (2010). Practice for Second Language Learning: Don't Throw out the Baby with the Bathwater. International Journal of English Studies, 10(1). https://www.um.es/ijes

q2 · i? · review · r2

Narrative review of educational psychology and L2 studies. The article reports the general benefit of distributed practice but states "spread ove r a couple of years may be worse than spread over a couple of months, or even spread over a year worse than spread over a semester".

"It has often been documented in educational psychology that distributing a given amount of practice over larger stretches of time is beneficial (see e.g. Seabrook, Brown, & Solity, 2005), but Collins, Halter, Lightbown, and Spada (1999) and Serrano (in press) show that there are limits to how far this distribution can go"

Kim and Webb 2022¶

Kim, S. K., & Webb, S. (2022). The effects of spaced practice on second language learning: A meta-analysis. Language Learning, 72(1), 269–319. doi:10.1111/lang.12479

q3 · meta-analysis (abstract only) · i? · no effect size printed in the abstract; spacing effect described as medium-to-large · n=48 experiments (98 effect sizes, N=3,411) · quant-synthesis · r?

This meta-analysis pooled 98 effect sizes from 48 second-language experiments (3,411 participants) on spaced practice, comparing spaced with massed practice, longer with shorter spacing, and equal with expanding spacing on immediate and delayed posttests. The authors report that spacing had a medium-to-large effect on second language learning; that shorter spacing was as effective as longer spacing on immediate posttests but less effective on delayed posttests; and that equal and expanding spacing were statistically equivalent. Differences in the spacing effect across studies were explained by the learning target, number of sessions, type of practice, activity type, feedback timing and retention interval. Read from the abstract only: it prints no pooled effect sizes, confidence intervals or spacing intervals, so the size of each comparison, the gaps the studies used and the learners' ages and proficiency are not established here. It supports the first half of this claim, that distributed practice benefits L2 learning; it does not bear on the second half, since nothing in the abstract concerns practice spread over years, and within the ranges its studies used, which the abstract does not give, longer spacing did better than shorter on delayed tests.

"Results showed that (a) spacing had a medium‐to‐large effect on second language learning; (b) shorter spacing was as effective as longer spacing in immediate posttests but was less effective in delayed posttests than longer spacing; (c) equal and expanding spacing were statistically equivalent"

Discussion¶

Kim and Webb's (2022) meta-analysis supports the benefit of spacing for L2 learning, and found longer spacing better than shorter on delayed posttests; it does not test the limit this claim's title asserts, which still rests on one narrative review's reading of two studies.

Related Claims¶

• The optimal interstudy interval increases as the retention interval increases — the general claim this finding bears on, with the studies behind it
• Distributed Practice Improves Retention — a broader claim this one bears on
• Gains from an intensive period of second-language study persist for weeks without rehearsal. — related
• FH2T was evaluated with nine 30-minute sessions spread across one academic year as a supplemental program — related
• Spaced and interleaved homework practice improves learning and retention — related
• All 48 reviewed spacing studies obtained the spacing effect using rest-from-deliberate-learning periods — related
• Spaced practice research addresses the potential for optimal gaps or delays between presentations of the same concept — related