Tuesday, September 28, 2010

ON BEING SURE

I heard a pediatrician tell a revealing story. It began when parents brought their eight-year-old son to the ER after he was bumped on the head and then temporarily confused. The doc examined the boy, concluded it was a soft-tissue injury unlikely to have residuals, and suggested the parents take him home and observe him for the next twenty-four hours.

"Uh uh," said the parents. "Let’s be sure with an MRI."

Well, why not? No one was using the MRI machine at the time, even though it needs almost constant use in order to be amortized, and what the hell, insurance would pay for it anyway. So the kid got the MRI.

The pediatrician ended the story by pointing out that the MRI result, "normal," didn’t leave anyone sure, only surer. Well, why can’t we have surer than surer? At this moment some technological breakthrough is on its way to every ER which will make the MRI look coarse, but will cost six times more. The question must arise: how much certainty do we need?

One reason American healthcare is so expensive is the premium we place on certainty. As a society, we don’t tolerate ambiguity well. Think about a time you endured, when just knowing what was happening, even though it might be awful, was better than not knowing. Uncertainty leaves a wide wake of fear. Recent history shows it can even cause wars.

But who would possibly oppose a quest for certainty? The surer we are, the less room there is for self-doubt. That’s part of our heritage, after all. “Be sure you’re right,” said Davy Crockett (or maybe it was just Fess Parker), “and then go ahead.”

The trouble is, though, that the universe itself is factually shaky. People have won Nobel Prizes for proving that certainty is a chimera, an illusory ideal. As soon as you’re sure where that electron is, it’s not there. Still, we strive for certainty, and we believe we can come close, but how close is permanently anyone’s guess.

As a sometimes carpenter, I can tell you that the art of progressing from a home’s foundation to its finish lies in reducing gaps, from foot-plus framing spaces down to cabinetry’s barely perceptible wedges. Medicine is no different. A sixteenth century doctor might have concluded after examining you that you had an infection. That at least put it in the ballpark. A late Victorian doctor might have narrowed it further, to “botulism infection.” Today’s doctor will read you, if you insist, the genome of the botulism bacterium.

We’re daily reducing gaps in medical knowledge, but at exponentially rising cost. A doctor who feels your abdomen and charges ninety dollars can estimate your spleen size within a centimeter or two, while a thousand-dollar CAT scan measures it a hundred times more accurately. To paraphrase anthropologist Gregory Bateson, is this a difference that makes a difference?

Failing certainty doesn’t mean we’re doomed to operate from ignorance. We make educated guesses about the world and navigate accordingly. I suspect the reason we’re on the planet more than a few weeks is to perfect our guesses, continually approach permanently elusive Truth. The good news and the bad news are identical: we’re doing the best we can.

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