Embedding peer assessment in MCQs has improved immediate performance but increased task duration without enhancing transfer.

Introduction: Multiple-choice questions are widely used in higher education and online training because of their scalability. This study examines whether incorporating peer assessment, such as evaluating written explanations accompanying students' answers, can increase students' cognitive engagement and improve learning outcomes in asynchronous settings. Methods: One hundred undergraduate science students were randomly assigned to three groups and completed a series of conceptual questions on an online platform. Group A responded to standard multiple-choice questions. Group B additionally evaluated fictional peer explanations using agreement ratings. Group C additionally provided written feedback. All participants completed four experimental questions followed by five transfer questions. Completion time and performance at each phase were recorded. Results: Students in both peer assessment groups demonstrated significant gains between initial and revised answers. A linear regression revealed a significant effect of the peer assessment type on immediate performance, with written feedback benefiting low-performing students more markedly. However, no group outperformed the control in the transfer questions. Task duration increased significantly with peer assessment, particularly for the group providing written comments. Discussion: Embedding peer assessment appears to enhance immediate MCQ performance, especially when students are required to articulate written feedback; however, it did not improve transfer performance and significantly increased task duration. The absence of measurable gains in conceptual learning raises questions about the cost-benefit ratio of such interventions in time-constrained educational settings. Further research is warranted to delineate the conditions under which such interventions yield long-term benefits.