GenAI-supported writing instruction yields a statistically significant positive pooled effect on L2/EFL writing performance (g = 0.80) with very high heterogeneity¶

Claim · All claims
Evidence · 1 study (2 entries) · quant-synthesis r3 · q3 · i3 large
Currency · newest study 2026 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i3 Across 11 study-level effects, GenAI-enhanced writing instruction shows a statistically significant pooled advantage over comparison conditions (g = 0.80, 95% CI [0.37, 1.22]), with substantial between-study heterogeneity (I2 = 92.21%). → Mark Feng Teng 2026

Evidence¶

Mark Feng Teng 2026¶

Mark Feng Teng. (2026). Effectiveness of GenAI in enhancing writing performance: a meta-analysis. Asian-Pacific Journal of Second and Foreign Language Education. https://doi.org/10.1186/s40862-026-00444-2

q3 · i3 · quant-synthesis · r3

Random-effects (DerSimonian–Laird) meta-analysis of 11 study-level Hedges' g effects from the expanded main synthesis, prioritizing between-group post-test overall writing outcomes. The pooled effect was "a statistically significant pooled effect of g = 0.80" with substantial heterogeneity (I2 = 92.21%, τ2 = 0.456).

"The primary random-effects meta-analysis (DerSimonian–Laird) in Table 2 yielded a statistically significant pooled effect of g = 0.80, 95% CI [0.37, 1.22], indicating a large overall advantage for AI-enhanced instructional conditions."

Mark Feng Teng 2026 (2)¶

Mark Feng Teng. (2026). Effectiveness of GenAI in enhancing writing performance: a meta-analysis. Asian-Pacific Journal of Second and Foreign Language Education. https://doi.org/10.1186/s40862-026-00444-2

q3 · i? · quant-synthesis · r3

Within the same 11-study synthesis, one graduate-level study (Ding et al., 2025, Hong Kong, N = 77) reported "a statistically significant negative effect ( g = −0.57, 95% CI [−1.03, −0.11])", the only negative effect among the included studies.

"One graduate-level study reported a statistically significant negative effect ( g = −0.57, 95% CI [−1.03, −0.11])."

Discussion¶

Related Claims¶

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