Just give me the treatment that works best, doc.

But what if the doctor doesn't know?

That's where comparative effectiveness research comes in. It studies vast numbers of patient records to determine which treatments work best for a given disease. The federal stimulus bill is pumping $1.1 billion into it, and that's a good prescription for what ails American health care.

We've heard stories about drug companies marketing expensive new pharmaceuticals that don't do any more to relieve a condition than older, much less expensive drugs do.

Or, to cite another example, which surgery works better to relieve a blockage in the carotid artery that could cause a stroke: reaming out the artery with surgery or implanting a stent?

If there were better answers to questions about which treatments are most effective and which are not, health care could be more effective for patients and less expensive, because unnecessary or ineffective drugs or procedures would be weeded out of practice.

Of course, it's not quite that simple. One patient's condition might swing the pendulum toward one treatment that might not be the best for other patients. But in general, knowing what works best in the greatest numbers of cases simply makes sense.

That's what the Institute of Medicine will be asked to figure out. Its job will be to prioritize different diseases and treatments for study.

This has caused some controversy, however, because critics say that such information could lead insurance companies to pay for one treatment and not another, or for government to ration care by deciding that Medicare or Medicaid would pay for only one treatment of a certain condition. Much of this concern has been stoked by drug companies that could lose out if their product is not chosen, or doctors who specialize in one therapy who might be stricken off someone's list.

While there is some basis in reality for that concern, it should not derail this program. The American taxpayer and patient have a vital interest in knowing which treatments are most effective, not only for health's sake but for the health of everyone's pocketbook. The high cost of health care is crushing both family and business budgets. We all have a stake in knowing what works. Certainly doctors do, too, or should.

Evidence-based medicine is one of the buzzwords in health-care reform. But first, you've got to have the evidence.