My husband told me about a patient who checked in to a Florida hospital for a life-saving amputation. He awoke to find that the wrong foot had been removed. IN the same hospital, another patient had surgery on the wrong knee.

Defenders of the healthcare system point out that such tragic cases of malpractice are like airline crashes—they are newsworthy because they are so rare. In that Florida hospital, officials responded with a plan to avoid what could go wrong: Staffers now write “NO” with a black Magic Marker on the healthy limb.