Is it too hard to figure out what incentives change doctors' habits?

The answer is probably yes. The authors of the book Freakonomics wrote a NY Times Magazine piece on how L.A.'s Cedars-Sinai Medical Center got its doctors -- who had the worst rate among hospital staff of cleaning their hands before attending to patients -- to change their ways.

The concept that doctors washing their hands regularly would saves patients' lives was established in 1847 when Dr. Semmelweis found:

The mortality rate in the doctors’ clinic was nearly triple the rate in the midwives’ clinic. Why the huge discrepancy? The doctors, it turned out, often came to deliveries straight from the autopsy ward, promptly infecting mother and child with whatever germs their most recent cadaver happened to carry. Once Semmelweis had these doctors wash their hands with an antiseptic solution, the mortality rate plummeted.

But still today, the Semmelweis Rule is hard to enforce. Why? "[f]or starters, doctors are very busy. And a sink isn’t always handy... [and] even with Purell dispensers mounted on a wall, ... doctors didn’t always use them." In addition there are psychological reasons: there's "a perception deficit" (in an Australian study, "doctors self-reported their hand-washing rate at 73 percent, whereas when these same doctors were observed, their actual rate was a paltry 9 percent") and there's “[t]he ego [that] can kick in after you have been in practice a while."

According to the writers, the incentives "were not quite aligned with the hospital’s."

At first the hospital team assigned to the task sent emails and faxes, and put posters up. But none of it worked. So the team moved onto rewarding those docs who complied with the Semmelweis rule.

They started a Hand Hygiene Safety Posse that roamed the wards and let it be known that this posse preferred using carrots to sticks: rather than searching for doctors who weren’t compliant, they’d try to “catch” a doctor who was washing up, giving him a $10 Starbucks card as reward. You might think that the highest earners in a hospital wouldn’t much care about a $10 incentive — “but none of them turned down the card,” Silka says.

When the nurse spies reported back the latest data, it was clear that the hospital’s efforts were working — but not nearly enough. Compliance had risen to about 80 percent from 65 percent, but the Joint Commission required 90 percent compliance.

Eventually, the entire staff was compliant! But how? Well, one day "after [a group of doctors] finished their lunch, Murthy [the hospital epidemiologist] handed each of them an agar plate — a sterile petri dish loaded with a spongy layer of agar. 'I would love to culture your hand,' she told them."

They pressed their palms into the plates, and Murthy sent them to the lab to be cultured and photographed. The resulting images... “were disgusting and striking, with gobs of colonies of bacteria.”

The administration then decided to harness the power of such a disgusting image. One photograph was made into a screen saver that haunted every computer in Cedars-Sinai. Whatever reasons the doctors may have had for not complying in the past, they vanished in the face of such vivid evidence. “With people who have been in practice 25 or 30 or 40 years, it’s hard to change their behavior,” Leon Bender says. “But when you present them with good data, they change their behavior very rapidly.” Some forms of data, of course, are more compelling than others, and in this case an image was worth 1,000 statistical tables. Hand-hygiene compliance shot up to nearly 100 percent and, according to the hospital, it has pretty much remained there ever since.

The writers state this tale demonstrates how playing around with and using the right incentives can effectively change old habits. But "it also highlights how much effort can be required to solve a simple problem — and, in this case, the problem is but one of many."

Playing around with incentives, then, may be too much work. And technology could possibly help making it easier not so much to change people's mind and habits but to circumvent them. Which is why the writers conlude their piece by mentioning that Craig Feied, a "physician and technologist who is designing a federally financed 'hospital of the future,' is working with a technology company that infuses hospital equipment with silver ion particles, which serve as an antimicrobial shield."

You can teach an old doc new tricks, but it requires a lot of time and effort and a new way of looking at things called incentives.