Book Description

Abstract: Introduction: The object of this research was to evaluate the reliability and validity of Peer Assessment Rating (PAR) index scores derived from computerized digital models. Computer based digital orthodontic models have been shown to be valid and reliable when making measurements of tooth size and simple diagnoses of dental malocclusions. The validity and reliability of PAR scores from digital models and plaster models that have been previously scored and standardized for a calibration exercise for the PAR index have not been established. Methods: Ten examiners were trained to score digital and plaster models using the PAR index. Thirty standardized and previously scored plaster PAR models used in PAR calibration were digitized using digital study model technology. The plaster and digital calibration models were randomized and scored by the ten examiners. All measurements were repeated by all examiners at a second session. Results: Plaster and digital scores were compared to the gold standard PAR scores for validity. The Intraclass Correlation Coefficients (ICC) for plaster models ranged from 0.808-0.926. The mean ICC for plaster models was 0.891 with a 95% confidence interval (CI) of 0.829-0.940. The ICCs for digital models ranged from 0.846-0.922. The mean ICC for digital models was 0.878 with CI of 0.811-0.931. Intra-rater reliability was excellent for plaster (ICC =0.919) and for digital models (ICC= 0.905). Inter-rater reliability was also good for plaster (ICC=0.912) and digital models (ICC=0.883). Conclusions: The PAR index scores obtained from the digital and plaster calibration models were shown to be valid and reliable.