Computer scientists at Carnegie Mellon University have developed an algorithm that could significantly boost the efficiency of kidney exchanges, a mechanism for matching live donors with unrelated recipients.
The algorithm makes it possible to create matches for three- and four-way exchanges -- that is, three or four donors matched to three or four recipients -- as well as two-way exchanges. According to the researchers, it is the first that is scalable so it can be used for a national pool of donors and recipients.
For example, in a match run recently, the algorithm identified four potential two-way exchanges, three three-way exchanges, and one four-way exchange among about 100 donor-patient pairs and seven altruistic donors (donors without specified recipients). With the same set of donor-patient pairs and without altruistic donors, the matching method previously used by the Alliance for Paired Donation -- a kidney exchange program for 50 transplant centers in 15 states -- would have identified only one two-way exchange.
