Comparison of Perceptual Assessment for Dysarthric Speech: The Detailed and General Assessments

Objectives: The Mayo Clinic rating of dysarthria is widely used in the clinical practice. However, because of its low reliability and extensive time requirement, it is necessary to reduce the number of components and improve its reliability. The present study was designed to investigate the difference between a general and detailed assessment protocol and the association of perceptual dimensions with overall impression of speech. Methods: Twenty-eight inexperienced clinicians were asked to perform both protocols twice, separated by a one week interval, with samples of standardized paragraph readings of 15 patients with various degrees and types of dysarthria. The inter-rater reliability, test-retest reliability, and different of rating values were compared between both protocols. The correlation between perceptual dimensions and overall impression of speech was also examined. Results: The general assessment protocol showed higher inter-rater reliability (=.967) and test-retest reliability (=.620) than the detailed assessment protocol. The mean rating values were similar between the two protocols, but there was a difference in the distribution ratio of rating values. For both protocols, dimensions related to articulation were highly correlated with overall impression of speech, and those related to resonance had low correlation. Conclusion: The general assessment protocol takes less time and has higher reliability than the detailed assessment protocol. However, since it is limited to evaluating speech characteristics of dysarthria in detail, it should be accompanied by other assessment protocols. The results of the present study are expected to be the basis for further studies.