The Effect of Group Decision-Making on Health Utility Biases

This paper explores the effect of group decision-making on the systematic biases present in health utility measurement. The experiment allows for the comparison between individual and group health utilities measured using the Time Trade-off (TTO) and Standard Gamble (SG) methods, the latter involving risk and the former being riskless. The results indicate a significant difference between the group and individual health utilities measured using the TTO method, but not the SG method. Furthermore, there is a significant difference between the SG and TTO utilities calculated for the grouped participants, but not the individual subjects. However, when the SG utilities are adjusted for prospect theory, a significant difference is found between the TTO and SG elicited health utilities for the individual participants, but not for the grouped subjects, indicating a reduction in biases is present in the grouped participants for the TTO method, but not when making use of the SG method.