Perceptual and laboratory assessment of dysphonia.

The voice laboratory is an essential tool in the voice clinic. It provides a functional diagnosis of disturbed voice production, demonstrating the deviant characteristics, limitations, and possibilities for change. As voice is multidimensional, several aspects need to be documented, quantified, and analyzed: perception, stroboscopy, aerodynamics, acoustics, self-evaluation by the patient, and in specific cases, physiologic signals, such as electroglottography, flow glottography, nasometry, and electromyography. Effectiveness and outcome studies rely on such data.