Acoustic measurement of pathological voice qualities for medical purposes

In order to develop an assessment system for voice quality to be used in voice clinics, acoustic correlates of pathological voices were investigated. Extracted measures were 1) modulation indices representing periodical variations in the pitch period, in the amplitude and in the waveform; 2) a pitch perturbation quotient; 3) an amplitude perturbation quotient; 4) a distortion factor representing richness of harmonics; and 5) the additive noise level. It was found that these acoustic measures can indicate the differences in the perceptual qualities of pathological voices very well.