PBL-taught learners showed significantly higher vocabulary retention on delayed post-tests in all modules except module 3¶
Claim · All claims
Evidence · 1 study · causalr2·q3
Currency · newest study 2015 · not yet checked against its sources · not reviewed by a person
Subclaims¶
Reading the evidence codes
q is the design tier, i the impact, n the sample, and the kind with its r
the rigour judged within that kind: what each code means.
This claim: no standardized effect is recorded in observations/ for it yet, so no benchmark reading is possible.
q3 i? The experimental group scored significantly higher on delayed post-tests administered five weeks after each post-test, except in module 3 where the difference was not statistically significant. → Shafaei 2015
Evidence¶
Shafaei 2015¶
Shafaei, A., & Abdul Rahim, H. (2015). Does project-based learning enhance Iranian EFL learners' vocabulary recall and retention? Iranian Journal of Language Teaching Research, 3(2), 83-99. https://www.urmia.ac.ir/ijltr
q3 · i? · causal · r2
Delayed post-tests (weeks 7-11) measured retention five weeks after each post-test; delayed post-test means were 26.05 (experimental) vs 21.30 (control), and the article reports significance in all modules except module 3, with no effect size printed.
"Results of the t-test reveal that the experimental group had a significantly higher delayed post-test score in all modules at a confidence level of 99 %, except for module 3 where the difference was not statistically significant."
Discussion¶
Learner Variables¶
- Long-Term Memory — outcome: instruction changes it
Related Claims¶
- The authors interpret the PBL group's better retention of later-module (harder) items as evidence that authentic learning environments aid difficult vocabulary — related
- On a delayed delayed-post-test covering all 30 items, the PBL group (mean 23.80) outperformed the control group (mean 17.15) — related
- PBL-taught Iranian EFL learners achieved significantly higher vocabulary recall (total post-test) than conventionally taught learners — related
- Authentic problem-based vocabulary tasks improve two-week retention of vocabulary compared with conventional input-based tasks — a broader claim this one bears on
- The PBL advantage over the conventional method held for modules with more adjectives but not for the noun-heavy modules 3 and 5 on recall — related
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