Inter-observer agreement in grading oral epithelial dysplasia – A systematic review

IntroductionOral epithelial dysplasia does not follow a predictable sequential progression from mild to moderate to severe dysplasia and in rare cases may revert to normal. It is not uncommon for a mild dysplasia to rapidly progress to an invasive carcinoma; however, not all epithelial dysplasia develops into carcinoma. Over the past decades, numerous grading systems have been proposed. However, dysplasia grading is still highly subjective with lack of objective criteria. This systematic review assesses the extent of inter-observer agreement in grading epithelial dysplasia of the upper aerodigestive tract.Materials and methodsArticles were searched in on-line databases, such as PUBMED, EMBASE and MEDLINE with key words “grading oral epithelial dysplasia, inter-observer agreement, reliability.” Manual search of Journals were also done. Articles were reviewed and analysed.ResultsOf the 11 relevant articles, two were excluded and the remaining nine were reviewed. Only three studies showed substantial inter-observer agreement, three showed moderate agreement, and three showed fair agreement.ConclusionWe recommend standardisation and practice of a universal grading system to achieve better inter-observer agreement in the future. Future systematic reviews based on such a system would probably be more homogeneous.