When Dying Patients Are Given a Wrong Number

News reports openly speculating about Sen. Edward Kennedy’s life expectancy after his brain-cancer diagnosis obscured a surprising truth about medicine: It doesn’t do a good job of estimating how many days dying patients have left. My print column this week points out that life-expectancy stats aren’t easily applied to individual patients, because age and other factors, some unknown, can make anyone an outlier. The process of translating statistics into predictions for any one patient is fur