Assessing Inter-rater Reliability of the Dental Practicality Index and the American Association of Endodontists Endodontic Case Difficulty Assessment Form among Undergraduates

Abstract

Dental Practicality Index (DPI) and American Association of Endodontists Endodontic Case Difficulty Assessment (AAECDA) form potentially can guide clinicians in making clinical decisions and triaging in large practices and academic settings. Nonetheless, the reliability and validity should be evaluated before institution-wide implementation. This study aimed to evaluate the inter-rater reliability of the DPI and AAECDA forms. Ten randomly selected, trained students rated 25 cases with both forms. The itemby-item inter-rater and overall reliability were estimated with Gwet’s agreement coefficient (AC2) and intraclass correlation coefficient (ICC), respectively. The association between clinical decisions and the scores was analysed with the Generalised Estimating Equation. The inter-rater reliability of DPI was generally very good (AC2 = 0.81–1.00), except context (good; AC2 = 0.718; 95% confidence interval [CI] = 0.575–0.861). The inter-rater reliability of AAECDA was generally very good (AC2 = 0.81–1.00) and good (AC2 = 0.61–0.80), except the radiographic appearance of the canal(s) (fair; AC2 = 0.424, 95% CI = 0.263–0.585). Moderate overall inter-rater reliability of AAECDA (ICC = 0.53, 95% CI = 0.38–0.70) and DPI (ICC = 0.62, 95% CI = 0.48–0.77) was observed. Referral to an endodontist was positively associated with AAECDA score (odds ratio [OR] = 1.323, 95% CI = 1.145–1.52, p < 0.001). The decision of tooth extraction was positively associated with the DPI score (OR = 1.983, 95% CI = 1.539–2.555; p < 0.001). In conclusion, DPI and AAECDA are methods with moderate inter-rater reliability when used among dental students.