The Effects of Immediate Versus Delayed Timing of AI Support on EFL Learners' Reading Comprehension Performance: An Experimental Study.

The growing integration of artificial intelligence (AI) into second-language reading instruction has intensified debate regarding whether AI-mediated support facilitates comprehension or reduces the cognitive effort required for independent meaning construction. Although previous research has reported generally positive effects of AI-assisted reading, limited attention has been directed toward the timing of support during the reading process itself. The present study examined whether immediate versus delayed AI support produced different effects on EFL learners' reading comprehension performance. A pretest-posttest experimental design was employed, involving 90 undergraduate EFL learners, randomly assigned to three instructional conditions: Immediate AI Support, Delayed AI Support, and No-Support control. The intervention was conducted over a ten-week period using AI-assisted reading tasks administered under controlled instructional conditions. Reading comprehension performance was measured using validated pre- and post-test instruments that assessed literal, inferential, and global comprehension. Psychometric validation procedures incorporating Classical Test Theory and Item Response Theory supported the instrument's reliability and measurement adequacy. One-way ANOVA revealed statistically significant differences across the three instructional conditions, F(2, 87) = 18.679, p < .001, η2 = 0.301. Post hoc comparisons demonstrated that learners receiving delayed AI support achieved significantly higher post-test reading comprehension scores than learners in both the immediate support and no support conditions. Learners receiving immediate AI support similarly outperformed the no-support group. The findings indicate that the effects of AI-assisted reading varied according to when explanatory support became available during the reading process. Delayed AI support produced stronger reading comprehension performance than immediate support and unsupported reading, suggesting that support timing constituted an important condition shaping comprehension performance in AI-mediated reading environments.