Prevalence of voice quality deviations in the normal adult population.

The purpose of this study was to determine the prevalence of voice quality deviations in a normal adult population. One-hundred twelve subjects, aged 17 to 80, read a short paragraph aloud into a high-fidelity tape recorder and completed a case history questionnaire. A group of 11 pretrained judges rated overall performance of each taped sample on a seven-point equal-appearing intervals scale, then designated those quality components which contributed toward deviant ratings. Eighty-two percent of the group received a mean severity rating lower than 1.99; 16% had a rating between 2.00 and 2.99; and 2% was assigned a mean rating higher than 3.00.