A study of examiner variability in assessment of preclinical class II amalgam preparation

Abstract

Introduction: Training in typodont preclinical restorative exercises is one of the ways by which the required manual skill dexterity could be developed in students. The assessment of these exercises has been associated with inter and intra examiner variability. This study was undertaken to examine whether introduction of objective scoring criteria can reduce the examiner variability and evaluate for inter and intra examiner variability in assessing class II amalgam tooth preparation by using two different methods i.e., glance and grade and objective checklist criteria scoring. Materials and Methods: The study evaluated 41 undergraduate students performing two Class II disto-occlusal amalgam preparations performed on plastic typodont left lower and upper first molars. The preparations were evaluated by four blinded independent examiners using two methods viz., glance and grade and objective checklist scoring methods. Statistical analysis for inter and intra examiner variability was tested using Friedman test and Wilcoxon signed rank test, respectively. Results: Results of this study show that intra-examiner variability was significantly reduced with objective checklist criteria scoring. The inter-examiner variability was present both in a glance and grading method and objective checklist scoring method. Conclusion: This study concludes by recommending that preclinical operative work of students be assessed by objective checklist criteria scoring and it should be introduced after sufficient training and calibration sessions to reduce examiner variability.