A comparison of grades awarded by peer assessment, faculty and a digital scanning device in a pre-clinical operative skills course




The aim of this study was to compare the grades awarded by two experienced assessors with peer-assessment marks and measurements from a digital scanning device (Prepassistant; KaVo, Biberach, Germany), for full gold crown preparations completed in a pre-clinical operative skills course on typodont teeth.


Seventy-eight preparations on typodont teeth were randomised and assessed by all three methods. Agreement was measured using weighted kappa statistics, and mean rank scores given by the Friedman test.


The highest agreement was seen between the experienced assessors (0.38), closely followed by peer assessment and experienced assessor agreement (0.36, 0.29). Despite this, the results indicate poor levels of agreement. No agreement was seen between any of the assessment methods when compared to the digital scanning device.


The findings of this study could be related to the difficulty of calculating a single grade from the output of the device, in addition to the inability of the machine to assess all the factors necessary for an acceptable preparation. From this study, it can be concluded that this device is not suitable for calculating grades when used in isolation. Further research could explore the role of the Prepassistant in providing student feedback, its potential to enhance the learning experience and the subsequent effect on performance.