International Journal of Technology Assessment in Health Care

General Essays

The ‘Utility’ of the Visual Analog Scale in Medical Decision Making and Technology Assessment: Is It an Alternative to the Time Trade-off?

Anne M. Stiggelbouta1, Marinus J. C. Eijkemansa2, Gwendoline M. Kieberta3, Job Kievita3, Jan-Willem H. Leera3 and Hanneke J. C. J. M. De Haesa4

a1 University Hospital Leiden

a2 Erasmus University Rotterdam

a3 University Hospital Leiden

a4 University Hospital Leiden and Academic Medical Centre, Amsterdam

Abstract

Methods often used for the valuation of health states are the time trade-off (TTO) and the visual analog scale (VAS). The VAS is easier than the TTO and can be self-administered; however it usually leads to lower scores. In the literature a power transformation of group mean VAS scores to TTO scores has been proposed. We were able to replicate this finding of a power function. We found coefficients that were very similar to those from the literature, for 183 cancer patients. The relationship existed independently of disease state and health status.