More doctors turn to evidence-based medicine.

Byline: THE HEALTH FILES By Tim Christie The Register-Guard

Doctors, for the most part, know what they're doing, or in the alternative, act like they know what they're doing.

No one wants to be seen by a fumbling, hesitant doctor, after all. They're the experts in the white lab coats with 10 years of medical training and the M.D. after their names.

So when the doctor walks into the exam room, we expect a thorough examination, an authoritative diagnosis, reassuring answers and a deftly scribbled prescription.

But doctors have been keeping a secret from their patients: Sometimes they don't know what they're doing. Sometimes they recommend a treatment not because there's a rock-solid foundation of medical evidence behind it, but because they think it works based on their experience and what they hear from other doctors.

"Unfortunately, for a good percentage of what we do in medicine, there isn't good evidence," said Dr. Lorne Bigley, a family physician at River Road Medical Group. "There isn't literature to support a lot of things we do."

That's why a growing number of doctors, nurses and researchers are changing the way they think about and practice medicine by seeking out drugs and treatments that are proven to work through randomized controlled trials.

The idea behind evidence-based medicine, or EBM as it's called, is simple in concept: Medical treatment should be based not on out-of-date textbooks or on what the crusty professor said years ago in medical school, but on what the best available evidence shows. That means using information derived from rigorously designed randomized controlled trials, and preferably more than one.

The history of medicine is rife with stories of treatments that turned out to do more harm than good once the evidence was in.

For years, when a patient suffered a heart attack, doctors would administer drugs to stop abnormal heart rhythms - and they wound up killing more patients than the number of American soldiers who died in Vietnam.

Doctors used to advise new parents to put their babies to sleep on their stomachs - a practice now viewed as a risk factor for sudden-infant death syndrome. When pediatricians began telling parents to put babies to sleep on their backs in the early 1990s, SIDS rates plummeted.

Perhaps the poster child for evidence-based medicine is hormone replacement therapy.

For years doctors prescribed a lifetime regimen of hormones for hundreds of thousands of women. Because women who took the hormones saw their cholesterol and other health indicators improve, doctors believed their risk of heart disease would decrease as well.

Then results from the massive Women's Health Initiative study showed that these drugs actually increased the risk of heart disease and were doing more harm than good.

"How could one of the most prescribed drugs of all time been unproven?" asks Ray Moynihan, an Australian journalist on the evidence-based medicine beat.

Sometimes, practicing evidence-based medicine means going against conventional medical wisdom.

For instance, many doctors will recommend that their male patients over 50 get a blood test, called the prostate specific antigen, or PSA, that screens for prostate cancer.

While a PSA can detect cancer, no published studies have shown that PSA testing reduces deaths from prostate cancer, said Bigley, the Eugene family doctor. In other words, just because doctors can detect the cancer, it doesn't necessarily mean they'll be able to keep it from killing their patient.

Some men get an aggressive type of prostate cancer that will kill them, no matter the treatment, Bigley said. Other men get relatively benign prostate cancer that will never affect their health - they'll die with the cancer, not from it.

Treating prostate cancer is not without risks, which include impotence and incontinence. That's why Bigley doesn't automatically order up a PSA when a patient asks. He explains there's controversy about the test, and shows them the evidence.

In the past 10 years, evidence-based medicine has gained momentum. The American Academy of Family Physicians bases nearly all its continuing medical education programs on evidence-based medicine, said Dr. Norman Kahn, the group's vice president for science and education. The group also publishes evidence-based clinical guidelines on their Web site.

"Physicians yearn to deliver what works," he said. "So when they learn there is evidence for this vs. no evidence for that, they are rapid adopters."

A major challenge for doctors practicing evidence-based medicine is simply keeping up with the massive volume of medical information. Doctors can get buried under the piles of medical journals on their desks, filled with articles of varying relevance and validity.

Bigley said he has resolved to read only evidence-based journals, including the Journal of Family Practice, which grades each article based on the quality of the evidence.

Springfield family doctor Pat Ahlen uses technology to help her practice evidence-based medicine. She subscribes to a Web site called InfoPoems.com - POEMS stands for Patient-Oriented Evidence that Matters. For $200 a year, she gets access to practical information that allows her to apply evidence-based medicine to her practice. She downloads the information to her Palm Pilot, allowing her instant access to information while with a patient.

It takes a little more time to practice evidence-based medicine, but patients seem to appreciate it, she said. In fact, most assumed doctors always have been doing it.

"If you're going to tell people to spend a lot of money on a certain procedure, you should have evidence-based data that shows in the long run they're either going to be less disabled or live longer," Ahlen said.