Inter-rater reliability of the Mallampati classification for patients in a dental hygiene clinic

The purpose of this study was to assess the inter-rater reliability between dental hygiene students and a supervising dentist using the Mallampati classification to evaluate and classify the pharyngeal soft tissues. A sample of 234 patients volunteered for the study. Mallampati classifications were performed by 21 dental hygiene students for patients during a 12 month period. During that same time period, the clinic dentist performed an independent assessment on the same patients. Quantitative research methods were used to evaluate the inter-rater reliability between dental hygiene students and the clinical dentist in performing the Mallampati classification. The data was analyzed using adjusted McNemar test for non-independent data, Kappa score and percentage of agreement with 95% bootstrap confidence interval. There was an agreement between the dental hygiene student and the dentist in the majority of the independent assessments with a p-value=0.498 from the adjusted McNemar test. Inter-rater agreement measured by Cohen's Kappa coefficient was 0.54 with a 95% bootstrap confidence interval of 0.42, 0.64. The percentage agreement was around 77% with a 95% confidence interval of 72%, 82%. It was concluded that dental hygiene students can evaluate and classify the pharyngeal soft tissues comparable to a supervising dentist in the clinical dental hygiene setting.