OBJECTIVES To help reduce pressure on faculty staff, medical students have been used as raters in objective structured clinical examinations (OSCEs). There are few studies regarding their ability to complete checklists and global rating scales, and a paucity of data on their ability to provide feedback to junior colleagues. The objectives of this study were: (i) to compare expert faculty examiner (FE) and student-examiner (SE) assessment of students' (candidates') performances on a formative OSCE; (ii) to assess SE feedback provided to candidates, and (iii) to seek opinion regarding acceptability from all participants.METHODS Year 2 medical students (candidates, n = 66) participated in a nine-station formative OSCE. Year 4 students (n = 27) acted as SEs and teaching doctors (n = 27) served as FEs. In each station, SEs and FEs independently scored the candidates using checklists and global rating scales. The SEs provided feedback to candidates after each encounter. The FEs evaluated SEs on the feedback provided using a standardised rating scale (1 = strongly disagree, 5 = strongly agree) for several categories, according to whether the feedback was: balanced; specific; accurate; appropriate; professional, and similar to feedback the FE would have provided. All participants completed questionnaires exploring perceptions and acceptability.RESULTS There was a high correlation on the checklist items between raters on each station, ranging from 0.56 to 0.86. Correlations on the global rating for each station ranged from 0.23 to 0.78. Faculty examiners rated SE feedback highly, with mean scores ranging from 4.02 to 4.44 for all categories. There was a high degree of acceptability on the part of candidates and examiners.CONCLUSIONS Student-examiners appear to be a viable alternative to FEs in a formative OSCE in terms of their ability to both complete checklists and provide feedback.