Knee osteoarthritis and health-related quality of life.

This section of the symposium addresses the definition, measurement, and relevance of health-related quality of life (HRQL) to osteoarthritis (OA) of the knee. Emphasis is placed on the multidimensional nature of HRQL and the fact that these measures can be used as either outcome or process variables. Clearly, HRQL has been accepted as an appropriate measure of treatment efficacy (an outcome measure) in most clinical research, augmenting the more traditional measures of morbidity and mortality. However, as this paper demonstrates, HRQL measures constitute important process variables in understanding disability and related concepts that are critical in designing effective therapies for treating knee OA.