The Comparisons of GRBAS Perceptual Judgments according to Levels of Utterances

The present study was performed to investigate adequate levels of utterances which can give essential as well as useful information about the patients' voice, by examining the degrees of correlation between the levels of utterances (vowels, words, and phrase paragraph reading) and the entire utterance including all of the levels. For this purpose, a total of 10 individual utterance samples (5 vowels, 3 words, 1 phrase, 1 paragraph reading) were collected from each of the 30 subjects with voice disorder patients, and four experienced voice therapists evaluated them using GRBAS. The results showed that four therapists highly agreed upon on 'G' parameter. The coefficient of the correlation between each level of utterance and entire utterance tended to be above 0.70. Judgements of the vowel /$\varepsilon$/ as well as /o/ highly correlated with the judgement of the entire utterance. Regardless of severity, the judgement of the entire utterance highly correlated with the judgements of the vowel /u/ and the paragraph reading. These results suggest that experienced voice therapists can precisely evaluate patients' voice quality with only one sustained vowel in the clinic field, as is done with the entire utterance evaluation.