World of Words produced a statistically significant medium effect on a comprehension composite measure (effect size 0.54) after 12 weeks¶
Claim · All claims
Evidence · 1 study · causalr?·q3·i2medium
Currency · newest study 2023 · 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 i2 In the Neuman et al. (2015) study, children receiving World of Words scored significantly higher than comparison children on the comprehension composite measure (effect size 0.54, improvement index +21, p < 0.01). → comprehension-composite
Evidence¶
comprehension-composite¶
What Works Clearinghouse, Institute of Education Sciences, U.S. Department of Education. (2023, August). World of Words. https://whatworks.ed.gov
q3 · i2 · causal · r?
Cluster randomized controlled trial (meets WWC standards without reservations) of 143 children in 10 classrooms across 5 state-funded preschool sites, assessed at the end of 12 weeks. Intervention mean was "0.35 (0.15)" versus comparison "0.27 (0.14)", with printed effect size 0.54 and improvement index +21.
"End of 12 weeks of implementation 143 children 5 preschool sites in the United States 0.35 (0.15) 0.27 (0.14) 0.54 +21 Yes (p < 0.01)"
Discussion¶
Related Claims¶
- World of Words produced a statistically significant medium effect on expressive vocabulary (Expressive One-Word Picture Vocabulary Test, 4th Edition; effect size 0.43) in a scaled-up 12-site study — related
- World of Words produced a statistically significant medium-to-large effect on a researcher-developed vocabulary inductive reasoning test (effect size 0.66) — related
- World of Words showed no statistically significant effects on the Woodcock-Johnson Picture Vocabulary Subtest or the PPVT-IV — related
- World of Words produced a large, statistically significant effect on taught-word sorting performance (effect size 0.94) in a two-site Head Start study — related
- Comprehension strategy instruction shows a large overall effect, but reliability is undermined by few standardized measures — related
Page metadata
| Field | Value |
|---|---|
type |
claim |
id |
world-of-words-comprehension-composite-significant |
title |
World of Words produced a statistically significant medium effect on a comprehension composite measure (effect size 0.54) after 12 weeks |
description |
World of Words produced a statistically significant medium effect on a comprehension composite measure (effect size 0.54) after 12 weeks |
status |
review |
evidence_strength |
moderate |
newest_evidence |
2023 |
generated |
by process:wiki-ingest on 2026-10-07 |
trust |
unverified — no one has confirmed this page's content |
sources |
1 — comprehension-composite |
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