摘要:A positive correlation between performance and participation in formative quizzes and final summative examinations has been reported many times. The goal of the present interview study was to construct a model to explain why students may elect not to engage with formative assessment opportunities. Our medical school’s preclinical curriculum has an established policy of offering weekly online quizzes in all courses during the first 2 yr. Quizzes do not count for credit. Semistructured interviews were recorded and transcribed verbatim, and a formal thematic analysis was applied. A total of 16 in-depth interviews were conducted, with 8 female and 8 male participants. Thematic analysis revealed four major interacting themes that we propose to converge to account for nonparticipation in quizzes: 1) inadequate feedback, 2) curriculum organization and student mistrust, 3) time constraints, and 4) fear of judgment. We propose seven practice points to improve the effectiveness of formative assessment quizzes of medical knowledge.