Is There a Difference in the Reliable Measurement of Temporomandibular Disorder Signs Between Experienced and Inexperienced Examiners?

Aims: To determine whether there is a difference in terms of reliability between experienced examiners and inexperienced examiners in the measurement of signs of temporomandibular disorders (TMD). Methods: A total of 27 patients seen for treatment of TMD were rated blindly and in random sequence by 2 experienced and 2 inexperienced examiners. The examiners participated in a 4-hour calibration session on the day preceding the reliability study. Both experienced and inexperienced examiners participated in the calibration session to reduce the effect of examiner subjectivity and allow the study focus to be on the effect of experience. The rating followed the Research Diagnostic Criteria for Temporomandibular Disorders and included mandibular movements, joint sounds, and digital palpation of muscles and joints. Intraclass correlation coefficients and kappa statistics were calculated to estimate interrater reliability. The Wilcoxon signed rank test was performed to test for differences between experienced and inexperienced examiners' results, and the Friedman test was used for differences between all 6 examiner combinations. Results: Excellent overall reliability was found for vertical mandibular motions, acceptable reliability was found for the summed muscle palpation pain sites, and moderate to poor reliability was found for excursive movements, joint sounds, and single muscle palpation pain sites. No significant differences in the measurement results could be found between the experienced examiners and the inexperienced examiners. Conclusion: Examiner calibration rather than professional experience seems to be the most important factor for reliable measurement of TMD symptoms. Keywords: calibration, reliability, temporomandibular disorders