Greenwood et al. (1993) reported a statistically significant CWPT effect on CTBS-Reading, but the WWC-corrected analysis was not statistically significant¶

Claim · All claims
Evidence · 1 study · causal r? · q3 · i1 small

Subclaims¶

q3 i1 The original study authors reported a statistically significant effect of CWPT on the Comprehensive Test of Basic Skills–Reading, but after WWC corrections for clustering the effect was not statistically significant, though the effect size of 0.35 remained substantively important. → ClassWide Peer Tutoring: WWC Intervention Report 2007

Evidence¶

ClassWide Peer Tutoring: WWC Intervention Report 2007¶

ClassWide Peer Tutoring: WWC Intervention Report. (2007). What Works Clearinghouse, U.S. Department of Education. https://www.jgcp.ku.edu

q3 · i1 · causal · r?

Randomized controlled trial with 218 sixth-grade students in six schools; Appendix A3 reports CTBS-U means of 46.17 (CWPT) versus 40.77 (comparison), a mean difference of 5.40, effect size 0.35, "ns" at α = 0.05, improvement index +14. Corrections for clustering were needed.

"Greenwood et al. (1993) reported a statistically significant effect of CWPT on the Comprehensive Test of Basic Skills–Reading. According to WWC analysis, however, the effect was not statistically significant. The effect size was large enough to be considered substantively important according to WWC criteria (that is, an effect size of at least 0.25)."

Discussion¶

Related Claims¶

• Large Type M (magnitude) errors almost certainly exist when applying the statistical significance filter in education research — the general claim this finding bears on, with the studies behind it
• In a five-year quasi-experimental study, the intervention program showed a statistically significant positive effect on fifth-grade reading performance assessment but not on the CTBS Reading subtest — related
• The intervention showed substantively important but WWC-unconfirmed effects on English language development, with non-significant CTBS Language and Writing outcomes — related
• EIR® had a positive, substantively important but statistically non-significant effect on first-grade reading comprehension — related
• Author-reported statistically significant program effects did not remain significant after WWC corrections for clustering and multiple comparisons — a broader claim this one bears on
• Statistically significant effects reported by the CDP studies were not statistically significant as recalculated by the WWC — related
• Nunnery and Ross (2007) reported significant grade 5 but not grade 8 TAAS effects, which were non-significant in WWC recalculation — related
• Peer pairing increases English learners' peer-directed language behavior but shows no significant effect on listening comprehension or teacher-directed language (Jun-Aust, 1985) — related