Concordance analysis between two questionnaires of self-reported bruxism

Abstract

Objectives: Consensus has not been reached regarding the diagnosis of bruxism. The present study analyzed the agreement between two self-reporting questionnaires for the diagnosis of possible bruxism. Methods: A non-probabilistic consecutive sample was selected among adult patients treated with implant-supported fixed prosthesis from 2010 to 2016. The sample consisted of 65 patients (42 women) undergoing oral rehabilitation with fixed implant-supported prostheses, who answered two structured questionnaires (Q1 and Q2) for the diagnosis of bruxism. Data were tested for agreement between both questionnaires using the Cohen's kappa coefficient. Results: The results showed a fair agreement (kappa = 0.356) between the two self-reporting questionnaires. Only 50% of the patients with a positive bruxism diagnosis in Q1 had the same diagnosis in Q2 and 46% with a positive diagnosis in Q2 had a similar result in Q1. Regarding the negative diagnosis of bruxism, 87% of patients with a negative diagnosis in Q1 also had a negative diagnosis in Q2, and 88% with a negative diagnosis in Q2 had a similar diagnosis in Q1. Conclusion: The results suggest that, although the use of self-reporting questionnaires for bruxism is a clinically easy method to apply in research and dental practice, this method presents limitations for obtaining a precise diagnosis of possible bruxism.