Multi-parametric evaluation of dysphonic severity

Summary: In recent years, the multi-parametric approach for evaluating perceptual rating of voice quality has been advocated. The present study evaluates the accuracy of predicting perceived overall severity of voice quality using a minimal set of aerodynamic, voice range profile (phonetogram) and acoustic perturbation measures. One hundred and twelve dysphonic individuals (93 females and 19 males) with laryngeal pathologies and 41 normal controls (35 females and six males) with normal voices participated in this study. Perceptual severity judgement was carried out by four listeners rating the G (overall grade) parameter of the GRBAS scale. The minimal set of instrumental measures was selected based on the ability of the measure to discriminate between dysphonic and normal voices, and to attain at least a moderate correlation with perceived overall severity. Results indicated that perceived overall severity was best described by maximum phonation time of sustained /a/, peak intraoral pressure of the consonant-vowel /pi/ strings production, voice range profile area and acoustic jitter. Direct-entry discriminant function analysis revealed these four voice measures in combination correctly predicted 67.3% of perceived overall severity levels.