Each of two drugs, S and T, greatly reduces the effects of potentially fatal heart attacks if given as soon as possible after the attack begins, but a trial has shown that use of drug T instead of drug S would prevent death in one additional case out of 120  Drug T, however, costs $2, 000 more per treatment than drug S
Ttherefore society is presented with a stark policy decision: whether or not to pay the $240, 000 it would cost to use drug T in order to save one additional patient
After a heart attack, drug T remains relatively effective if given at a time at which drug S is no longer effective.