The role of heterogeneity of patients' preferences in kidney transplantation.

We elicit time and risk preferences for kidney transplantation from the entire population of patients of the largest Italian transplant centre using a discrete choice experiment (DCE). We measure patients' willingness-to-wait (WTW) for receiving a kidney with one-year longer expected graft survival, or a low risk of complication. Using a mixed logit in WTW-space model, we find heterogeneity in patients' preferences. Our model allows WTW to vary with patients' age and duration of dialysis. The results suggest that WTW correlates with age and duration of dialysis, and that accounting for patients' preferences in the design of kidney allocation protocols could increase their welfare. The implication for transplant practice is that eliciting patients' preferences could help in the allocation of "non-ideal" kidneys.