Usefulness of Direct Magnitude Estimation (DME) and Acoustic Analysis in Measuring Dysphonia Severity

The purposes of this study were (1) to analyze the reliability of direct magnitude estimation (DME) in auditory perceptual assessments measuring dysphonia severity and (2) to analyze the relationship between DME and four acoustic parameters (cepstral peak prominence [CPP], cepstral peak prominence-smoothed [CPPs], Acoustic Voice Quality Index [AVQI], and Acoustic Breathiness Index [ABI]) and (3) to predict dysphonia severity based on DME using four acoustic parameters.

One hundred and sixty-one voice samples for dysphonia patients were used. In this study, we combined sustained vowel samples and connected speech samples using the Praat software to make the concatenated samples for implementing acoustic analysis and auditory perceptual assessments. For acoustic analysis, we analyzed each value of CPP, CPPs, AVQI, and ABI. For auditory perceptual assessments, three speech-language pathologists evaluated dysphonia severity from the concatenated samples. Finally, we performed a stepwise multiple regression analysis to verify which combination of the four acoustic parameters could best predict perceived dysphonia severity based on the DME.

DME was found to have high reliability for auditory perceptual assessments measuring dysphonia severity, and there was a significant correlation between DME and four acoustic parameters. Finally, a two-variable model (AVQI and ABI) was useful for predicting perceived dysphonia severity based on the DME.

We verified the usefulness of DME scales in judging the dysphonia severity of dysphonic patients when used with acoustic analysis. Also, the two-variable model was useful to predict perceived dysphonia severity based on the DME.