The effect of task repetition on L2 learners’ writing performance: A meta-analysis

This study systematically reviewed previous research on the effects of task repetition (TR) on second language (L2) learners’ writing performance (WP) and conducted a meta-analysis to analyse the moderating variables. A total of 17 independent studies involving 442 participants were included. The results showed that TR could significantly enhance L2 learners’ WP (g = 0.25, p < .01), though the effect size varied across different dimensions. Specifically, a significant positive medium effect size was found for fluency in L2 learners’ WP (g = 0.51, p < .01), while accuracy and lexical complexity showed significant positive small effect sizes (g = 0.24 for both, p < .01 for both). In contrast, the positive effect on syntactic complexity was minimal and not statistically significant (g = 0.06, p = .57). Three variables including repetition interval, writing genre, and writing medium, exhibited distinct moderating effects. TR was found to be more effective with a one-week interval, in argumentative writing tasks, and when conducted in a computer-mediated environment. Although other factors, such as the repetition number, repetition type, language proficiency and age of the learners, and interaction style did not moderate the effect, they indicated general trends that offer valuable guidance for implementing TR. For instance, it can be argued that one repetition is sufficient to improve learners’ WP and that TR may serve as a more efficient tool for adult learners. Overall, TR is an effective strategy for improving L2 learners’ WP, regardless of their language proficiency, repetition type, or interaction style. The results of this study can serve as valuable guidance for L2 instructors in implementing TR effectively in their teaching practices. Given the current scarcity of research on TR’s impact on L2 learners’ WP, further studies are recommended to explore how TR can be optimized to enhance L2 learners’ WP.