The aim of this study is to establish relevant objective parameters for evaluating dysphonia following unilateral vocal fold paralysis. To do so, the study compares objective and perceptual voice measures. The objective measures were obtained using a voice analysis software (Evaluation Vocale Assistée), whereas the perceptual measures were established with the GIRBAS Scale (grade, instability, roughness, breathiness, asthenia, and strain). All measurements were performed on 40 voice samples: 28 dysphonic subjects with unilateral laryngeal paralysis, and 12 control subjects. The intra- and inter-judge agreements were fairly good, at least for control subjects. The six GIRBAS measures obtained from the pathological voices were higher than those from the control voices (p < 0.001) and the correlation between both groups was good. Grade, breathiness and asthenia correlated with the objective parameters that express the aperiodicity of the phonatory signal (p < 0.01), namely, the coefficient of variability of the fundamental frequency, the coefficient of variability of intensity, and jitter. Our findings suggest that the perceptual reality of laryngeal paralysis-induced dysphonia depends more on grade, breathiness and asthenia than it does on roughness or instability.
Copyright 2001 S. Karger AG, Basel