Assessing quality of life in clinical research.

In clinical research the objective has increasingly become to improve an individual's quality of life (QOL). That is, increasing both the direct as well as the indirect aspects of an individual's life. Simple, reliable measurement techniques for QOL with well-established theoretical foundations are warranted, despite the difficulty in measuring QOL. Such measurement techniques will not only provide accurate measurement of QOL, but allow for broad comparisons. This paper aims to introduce and explain the three most widely used techniques for assessing QOL: the Visual Analog Scale, the Standard Gamble, and the Time Tradeoff technique. We will discuss the background and interpretation of these methods. In addition, we measure the QOL of severe carpal tunnel syndrome using the various techniques and contrast the results. An increased understanding of how QOL is measured and used in health and medicine will aid clinicians and clinical researchers. Furthermore, utilizing QOL as the outcome of interest may allow researchers to perform more powerful studies.