Being Mortal

A study led by the sociologist Nicholas Christakis asked the doctors of almost five hundred terminally ill patients to estimate how long they thought their patient would survive and then followed the patients. Sixty-three percent of doctors overestimated their patient’s survival time. Just 17 percent underestimated it. The average estimate was 530 percent too high. And the better the doctors knew their patients, the more likely they were to err.