Outcome measurements and quality of life in voice disorders.

The World Health Organization considers health as a multidimensional concept encompassing physical, mental, and social states of being. 21 A change in any one of these states as a result of treatment is considered to be an outcome of treatment. Treatment usually relates to the physical well-being of a patient, and physical well-being usually takes priority in attempts to assess the success of a treatment. For example, a patient with high blood pressure who is overweight may look and feel healthier after losing excess weight, but traditionally the blood pressure measurement has taken priority in assessing the change in status. The fact that the patient may look healthier is a secondary aspect of treatment and often is not considered within the strict medical model. A more comprehensive model might seek to address the patient's own impression of the change following weight loss and reduced blood pressure. Thus, the patient's attitude, feelings, and general change in status may reflect a greater degree of overall improvement than the reduction of blood pressure alone. This overall improvement reflects the change in the patient's quality-of-life status as a result of weight loss. Quality of life is one way to assess the overall outcome of the physical, mental, and social well-being of a patient following treatment for a health-related problem. The measurement of outcomes following treatment for voice disorders is in its infancy. In fact, the whole discipline of outcomes research remains in infancy except for the physical outcome measures that are considered within the traditional medical model. In this article, the outcome measures available for voice disorders are reviewed within a framework of perceived handicap and quality of life. At the outset, it should be noted that quality of life is a global measure of outcome. Although quality of life is comprehensive, encompassing social, psychosocial, mental, and physical treatments, it must not be substituted for the diagnostic assessment of physical symptoms that persist despite treatment. Moreover, global quality-of-life assessments may not reflect changes in a specific condition such as a voice disorder. Outcome measurement and research have been a topic of discussion by the medical community, the government, and insuring agencies for the past 25 years. Whereas the medical community has focused on physical outcome measures, other agencies have looked at outcome to determine treatment effectiveness. Outcome measurement is somewhat different from assessment of disease status, because the outcome does not directly address treatment efficacy, but rather addresses the value of a particular treatment for a particular individual. This value may be considered treatment effectiveness. Efficacy, on the other hand, evaluates whether, based on previous studies, a treatment can produce a predicted result or an expected result. 16,18,20 Outcome measurements look at treatment effectiveness from either a patient's perception of improvement or from objective measures related to normal function. Outcome measurement does not attempt to control certain variables that efficacy studies would control. Thus, outcome measurement is, to a large extent, subjective and highly individualized. The outcome data may be substantially different for two patients with the same diagnosis and the same treatment. Outcome research and measurement focus on the patient's perception about the entire process. Does the patient seem to be better as a result of a routine that was primarily designed to treat a medical disease?