Should we consider including a value for "Hope" as an additional benefit within health technology assessment?

Health technology assessment (HTA) typically uses average health-related quality of life gain as its main measure of benefit used in economic evaluation. Nevertheless, there have been calls to consider novel aspects of benefit including the "value of hope," defined as a patients' potential preferences for a wider distribution of treatment benefit with a positive skew, in the hope that they will be one of the lucky ones. The value of hope may also derive from feeling hopeful as a positive mental state, which may be missing from current measures of health-related quality of life. The value attributed to feeling hopeful could be related to, or additional to, the value derived from possible risk-seeking preferences. Here, we reflect upon the strength of the case for the inclusion of the "value of hope" taking a critical look at the commonly referenced evidence for including the "value of hope" as risk-seeking preferences. We also draw attention to other conceptions of hope-as an emotion, a cognitive process, or a combination of both-and reflect upon the potential of including these broader notions of hope into HTA. The case for the inclusion of the "value of hope" based on risk-seeking preferences is weak. We suggest research questions that could give further evidence on whether hope is an important missing value from HTA.