Do Kidney Exchanges Improve Patient Outcomes? An Analysis of Crowd-Out, Graft Survival, and Match Quality

Addressing the increasingly unmet demand for transplantable kidneys in the U.S. requires creativity due to legislation that prohibits buying and selling organs. In order to increase the number of successful transplants that take place, transplant centers have begun to implement kidney exchange programs. A patient in need of a kidney trans-plant and a willing but incompatible living donor can enter into an exchange program, where an incompatible donor from one pair is matched to a recipient in a second pair, and vice versa. These arrangements can extend to three or more pairs in self-contained groups, indefinitely through the use of donor chains started by altruistic donors, or simply between a single pair and a patient on the waiting list in exchange for increased priority. In this paper, I first estimate the number of additional transplants gener-ated by kidney exchanges by analyzing how the probability of receiving an exchange transplant affects the probability that a patient experiences other transplant outcomes, including death while waiting. To do this, I create a novel measure of exchange preva-lence that exploits variation in exchange activity across time and transplant centers