Writing interventions improve writing quality, the most frequently assessed outcome, with an effect of 0.33 for US ELL students¶

Claim · All claims
Evidence · 1 study · quant-synthesis r3 · q3 · i1 small
Currency · newest study 2026 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i1 Writing quality, assessed in 33 comparisons across 16 studies, showed an effect of 0.33. → Aitken 2026

Evidence¶

Aitken 2026¶

Aitken, A. A., Graham, S., Cao, Y., & Nusrat, A. (2026). The Impact of Writing Instruction for English Language Learners in the United States: A Meta-Analysis. Educational Psychology Review. https://doi.org/10.1007/s10648-026-10197-6

q3 · i1 · quant-synthesis · r3

Separate weighted mean effect size estimated for writing quality, the most commonly assessed outcome in the synthesis. The printed effect size for this outcome is 0.33: the article states writing quality was "the most frequently assessed outcome (in 33 comparisons across 16 studies) and showed an effect of 0.33", a small standardized effect.

"Writing quality was the most frequently assessed outcome (in 33 comparisons across 16 studies) and showed an effect of 0.33."

Discussion¶

Learner Variables¶

• Writing Skills — outcome: instruction changes it

Related Claims¶

• Strategy instruction significantly improves the writing of US ELL students (g = 0.36) — a narrower finding that bears on this claim
• Writing instruction produces a statistically significant positive overall effect on the writing performance of K-12 English language learners in the United States (g = 0.33) — possibly the same claim (merge candidate)
• Writing intervention effects for US ELL students do not vary significantly by study quality indicators, participant characteristics, or intervention characteristics — related
• The pooled effect of writing instruction for US ELL students is robust to sensitivity analyses but funnel plot asymmetry suggests possible missing positive effect sizes — related
• Process writing yields a meaningful but not statistically significant effect (g = 0.51) on US ELL students' writing — related