Recovered from the original publisher: Kellogg Insight
In the delicate and uncertain world of organ transplantation, for example, transplant surgeons occasionally resort to gaming the system in an effort to save their patient’s life. Because there are never enough donor organs to go around, patients are put on transplant waiting lists and prioritized based on a score that measures the severity of their illness. This has encouraged some doctors to be more liberal about ordering certain medical treatments or interventions that would bring their patients higher up on the waiting list—like sending them to the hospital intensive care unit (ICU) even when it might not be essential.
UNOS, a nonprofit organization that matches donor organs to waitlisted patients, “actually stopped using the ICU as a factor in prioritizing liver transplant patients because of the abuse of that method,” says James Schummer, a Kellogg associate professor of managerial economics and decision sciences who studies resource allocation. “And once UNOS decided to stop, ICU treatments for liver transplant patients dropped by half. That’s how severe this ‘gaming’ problem could be.”
Certainly, many of the doctors who gamed the system were only trying to do right by their patients. But what if there was a way to correct these distorted incentives? Schummer and Edwin Muñoz-Rodriguez of the College of Mexico came up with an idea: reserve a small fraction of the available organs that would normally go to the highest-risk patients and offer them to lower-risk patients instead. This rationing, the economists believe, could lower doctors’ incentive to over-treat their patients—while also increasing the odds that higher-risk patients will receive the organs they need.
To test their theory, Schummer and Muñoz-Rodriguez created a mathematical model of patients, doctors, treatments, and a “planner” in charge of allocating donor organs (much like UNOS). The model showed that a planner could always find a “sweet spot” where, even if a fraction of organs was set apart for lower-risk patients, all the patients in the system would have a better chance of receiving an organ—especially the sickest ones. In other words, the researchers’ approach would always deliver better results than the conventional method of only prioritizing the highest-risk patients.
“It’s kind of paradoxical: You’re paying off some of the patients not to game the system,” Schummer says. “And at the end of the day, they all still come out ahead.”
Switching lanes
Ordering extra medical treatment, like a stay in the ICU, in order to get higher up on the waiting list isn’t trivial for patients. “Being in the ICU is, frankly, pretty unpleasant. You don’t want to be there if you don’t have to be,” says Schummer. And these patients are hardly malingering; anyone whose name is on a transplant waiting list is already in bad shape. So what’s the harm in doctors gaming the system a bit?
The harm comes from what Schummer calls “congestion effects.” As the name implies, these effects occur when there is crowding around a desirable resource, making it less accessible to everyone.
Schummer compares the transplant waiting list to traffic on a busy highway. Everyone is headed toward the same destination—that is, receiving a donor organ—but some people are farther ahead than others. The sickest patients, however, ought to have a way of getting there faster—something like a carpool lane. And indeed, they do: just as cars with more occupants are rewarded with access to a less-crowded carpool lane, patients who are more sick get higher priority.