Imagine for a moment a fantasy health care system that acted in its own enlightened self-interest and for the benefit of the individuals it served and the health of the populations they composed. Describing such a system would call for a different language. Out would golofty talk of rights and entitlements and endless argument about who pays for what and how much. In would come one down-to-earth question: What is it that we are buying?

It is a fantasy because of the gap between what we know and what we do, between the output of biomedical discovery and its translation into...