A Comparative Study on Acoustic Voice Quality Index Between the Subjects with Spasmodic Dysphonia and Normophonia

Spasmodic dysphonia is one of the neurologic voice disorders that is rare, chronic and long term caused by excessive or inappropriate contraction of the laryngeal muscles. The condition is more common in females than males. Assessment of such disorders requires acoustic, perceptual, instrumental and self-reported rating scales for effective diagnosis and intervention. The Acoustic Voice Quality Index is a recent, multivariate acoustic measure of dysphonia measuring the overall quality of voice including both vowels and connected speech in Praat software using AVQI script. The study aimed at comparing, observing and analysing the thresholds of AVQI obtained in the two groups. The study also targeted to show an effective co relation between GRBAS scale and thresholds of AVQI using sustained vowel /α/ and Bengali oral passage. A total of 14 participants were chosen with age range 20-50 years, 7 participants were normophonic and 7 participants were having spasmodic dysphonia. Comparison was done between the 2 groups showing a significant difference (p < 0.05) between the groups. A strong co relation was obtained (α = 0.98) between two scales. Thus AVQI does the job of appropriate diagnostic tool for obtaining the scores of dysphonic population and need to be explored in other voice problems.