Peer-group assessment of pre-clinical operative skills in restorative dentistry and comparison with experienced assessors.

OBJECTIVE: In order to assess the feasibility of moving away from a tutor-assessed summative assessment to a peer-group marked assessment with more formative value, a study was undertaken to investigate if any differences existed between marks given by a peer group acting as examiner when compared with experienced assessors. The null hypothesis was that no differences in grades would exist between the examiners. METHODS: A total of 130 ivorine teeth set in dentoform models (mounted in phantom heads) were prepared by undergraduate preclinical students. The prepared teeth were randomly allocated for assessment to one of six student groups who met and graded each tooth preparation. Notes on common errors were supplied together with a list of multiple exemplar grades (of the full range of grades) and associated comments, together with a list of grade descriptors (for the five-point scale A-E) and a sectioned silicone index. The same preparations were independently assessed by two experienced restorative academic examiners using the same guidance. RESULTS: The mean rank scores given by a Friedman test did not show any statistically significant difference (P = 0.531). Kappa scores for inter-examiner agreement varied from 0.318 to 0.530. CONCLUSIONS: The data from the present study do not show any significant differences in grades awarded by experienced examiners to those awarded by a peer group. Peer-group assessment may be useful to encourage a greater understanding of concepts and principles underlying the development of operative skills.