Journal of voice : official journal of the Voice Foundation vol:17 issue:4 pages:544-56
In a group of chronically dysphonic patients, a voice range profile, or phonetogram, was recorded before and after receiving voice therapy and again 3 months later. The voice range profiles took a wide variety of shapes. Therefore, only measures that did not depend on a smooth contour could be used to describe changes before and after therapy. The main effect of voice therapy was an enlargement on the side of low frequency and low intensity.