<![CDATA[Oral epithelial dysplasia (OED) grading determines the management guidelines for oral potentially malignant disorders (OPMDs). The subjectivity of OED grading considerably impacts its reliability. Objective: This study aimed to assess the reproducibility of and variability in diagnosing and grading OED by oral and medical pathologists, using the conventional WHO 2005 classification. Material & methods: Five oral pathologists and one medical pathologist individually examined 200 hematoxylin and eosin-stained histological slides diagnosed as OED from oral pathology archives at the University of Peradeniya. The most experienced examiner’s diagnoses represented the standard for evaluating inter-examiner variability using the unweighted Cohen’s kappa coefficient. Results: OED grading among all oral pathologists revealed moderate agreement (kappa value, 0.42–0.50), whereas the medical pathologist showed poor agreement (kappa value, 0.034). The accepted OED diagnoses were mild, 33%; moderate, 24.9%; severe, 32.4%; and no dysplasia, 9.7%. However, 86.5% of the diagnoses by the medical pathologist were mild-no dysplasia. Diagnoses of moderate and severe dysplasia had lesser reproducibility than those of no dysplasia. Conclusions: OED grading was only moderately reproducible among oral pathologists and poorly reproducible with regard to the medical pathologist. A more reliable OED grading system is required to improve reproducibility for optimal OPMD management and assessment.]]>
