IntroductionThe purpose of this study was to simultaneously assess impact of enhanced training and anonymity on frequency, constructiveness, and professionalism of open-ended comments provided on course and instructor evaluations. MethodsIn a 2 × 2 factorial study, didactic students at one doctor of pharmacy program were randomized to receive enhanced training in providing constructive feedback on student evaluations of teaching or an unrelated control activity at the beginning of the academic year, and to provide or not provide an electronic signature at the time of evaluation completion for two consecutive semesters. After ensuring intercoder reliability and agreement among all investigators, one external investigator coded all open-ended comments based on the following factors: comment provided/comment not provided, constructive/less than constructive, professional/unprofessional, training/no training, and signed/unsigned. ResultsOf 836 opportunities to respond to open-ended items, 646 (77.3%) written comments were provided, which was similar by training (76.6% vs. 78.0%, p = 0.631) and signature (76.1% vs. 78.5%, p = 0.401) status. Of the 646 comments, 85.1% (n = 550) were constructive and 98.0% (n = 633) were professional. Students in the untrained/signed group were associated with decreased constructiveness (78.3%, OR 0.43, 95% CI 0.25–0.76, p = 0.003); overall, training was associated with increased constructiveness (88.3%, OR 1.70, 95% CI 1.09–2.65, p = 0.019). No factors were negatively or positively associated with professionalism when accounting for covariates. DiscussionMost students provided comments on course and instructor evaluations; most were constructive and professional. ConclusionStudy group assignment did not substantially impact comment frequency or professionalism. Assignment to enhanced training, regardless of signature status, significantly increased constructiveness.