An Examination of Pre- and Posttreatment Acoustic Versus Auditory Perceptual Analyses of Voice Across Four Common Voice Disorders.

Objective: The objective, instrumental acoustic measure of Cepstral Spectral Index of Dysphonia (CSID) correlates with audio-perceptual measures, is sensitive in detecting voice abnormalities, and tracks change following treatment. The goals of the current study were to (1) test the agreement between CSID versus auditory perceptual measures of pre- versus posttreatment voice change, and (2) investigate whether change in scores is based on voice disorder or phonemic structure of sentence stimuli.

Methods: Forty patients with benign voice disorders produced sentences and a sustained /a/ vowel from the Consensus Auditory Perceptual Evaluation of Voice protocol before and after treatment. CSID was calculated, and overall audio-perceptual voice severity was judged by 7 blinded, trained raters using a 100-mm visual analog scale. Differences between CSID and audio-perceptual measures of voice change across voice disorder and stimuli, and correlation between change in CSID and perceptual rating scores were assessed pre- and postintervention.

Results: Across all subjects, there were significant correlations between CSID and perceptual ratings change scores (P < 0.001), and no significant differences in pre- and posttreatment change. Disorder-specific analyses indicated that all tested sentence/vowel contexts are effective measures for pre- versus posttreatment change in atrophy and paralysis cases. Acoustic versus perceptual measures of voice change were significantly correlated in lesion cases for the sentence "How hard did he hit him" and with all sentences combined. There were no significant findings observed for muscle tension dysphonia.

Conclusion: CSID provides an accurate objective correlate to auditory-perceptual posttreatment change in overall voice severity ratings. Implications for outcomes testing and disorder-specific findings are discussed.