Perceptual Evaluation of Voice Quality and Its Correlation with Acoustic Measurement

The GRBAS scale is a widely used subjective measure of voice quality. The aim of this paper is to investigate the correlation between the ´grade´, ´roughness´, ´breathiness´, ´asthenia´ and ´strain´ dimensions of this scale and the objective measurements provided by the ´Analysis of Dysphonia in speech and Voice´ (ADSV) software package. To do this, voice recordings of 107 samples were collected in a quiet room, and each voice was perceptually evaluated on the GRBAS scale by three experienced speech and language therapists. The same recordings were also acoustically analysed using ADSV. Statistical analysis using the Spearman´s rank correlation coefficient model identified a degree of moderate correlation between the result of cepstral based analysis and the GRBAS scale. A classifier such as a decision tree may then be applied to the ADSV cepstral measurement for the objective prediction of GRBAS scores. The accuracy of the classifier in predicting the score of each therapist is given in the paper.