Online feedback is frequently implemented during second/foreign language (SL/FL) writing tasks and assessments. This meta-analysis investigates the effectiveness of online feedback in SL/FL writing. After careful screening and the application of inclusion and exclusion criteria, this study synthesizes the results of 17 primary studies reporting on students’ English SL/FL writing quality after online feedback. The studies involved 1568 students, and the results indicate a Hedges’ g effect size of 0.753 for the effectiveness of written feedback in general. Online feedback from teachers/instructors produces a larger effect size (g = 2.248) than online peer feedback (g = 0.777) and online automated feedback (g = 0.696). It was also found that educational levels and task genre mitigate the impact of online feedback on writing quality. Overall, the findings contribute to a better understanding of the impact of online feedback on ESL/EFL writing and provide insights into online ESL/EFL writing instruction.

在线反馈经常在第二/外语（SL / FL）写作任务和评估过程中实施。这项荟萃分析调查了在线反馈在SL / FL写作中的有效性。经过仔细筛选并应用了包含和排除标准，本研究综合了17项主要研究的结果，这些结果报告了在线反馈后学生的英语SL / FL写作质量。这项研究涉及1568名学生，结果表明，一般而言，对于书面反馈的有效性，对冲的g效应值为0.753。教师/教师的在线反馈产生的效果大小（g  = 2.248）比在线同伴反馈（g  = 0.777）和在线自动反馈（g = 0.696）。还发现教育水平和任务类型减轻了在线反馈对写作质量的影响。总体而言，这些发现有助于更好地理解在线反馈对ESL / EFL写作的影响，并提供对在线ESL / EFL写作指导的见解。