WIN Wyoming
Thought Bullets
for
July 2006
Evidence-based Medicine
I remember a very dear friend of mine in Cooperative Extension named Mary O. Warren. Mary O passed away a few years ago, but the many life lessons she taught me remain. Mary O offered this insight about patients with a medical problem who go to their family practice physician: about 80-90% of patients get better, regardless of what their doctors do or don’t do; about 1-3% of patients die, regardless of what their doctors do or don’t do; about 10-15% of patients would have gotten better on their own, but recuperated faster thanks to a doctor’s’ intervention. I have no idea if Mary O’s percentages are accurate, but they reflect my experiences with modern medicine. I recently read an article in Business Week entitled “Medical Guesswork.” I was so enthralled by the article I couldn’t put it down, and indeed I read it a second and third time. I highly recommend you read the entire article, but until you have the opportunity to do that, here are a few highlights from the article that caught my attention.
Dr. David Eddy is considered the father of health economics. He is a surgeon turned mathematician and healthcare economist. He is an advocate for “evidence-based medicine.” Dr. Eddy has spent his career exposing what he calls the dark secret of modern medicine. That is, there is little or no evidence that many widely used treatments and procedures actually work better than various less expensive alternatives. That may explain why the U.S. high-tech health care system now costs $2 trillion a year, at the same time most Americans’ health status lags behind people from other developed countries.
Dr. Eddy’s controversial career has set out to prove that the practice of medicine is more guesswork than science. One common medical practice he questioned and changed was the practice of preventing women from giving birth vaginally if they previously had a cesarean. He also proved the annual chest x-ray was worthless.
Dr. Eddy is quick to state that it would be a mistake to blame doctors for the lack of evidence-based medical practices. Most patients come to doctors with a combination of diseases and Dr. Eddy states the human brain is not capable of sorting out the complex probabilities associated with the numerous treatment options. That is why Dr. Eddy is leading a team to develop a computer model that will help doctors and patients make complex decisions. Put simply, a doctor’s clinical judgments are now woefully outmatched by the current complexities of medicine.
There is also the issue of economic interests of doctors and specialists. When there is a clear lack of evidence-based information and a host of treatment alternatives, then doctors are likely to prescribe what they know best. Dr. Eddy gives the example of a person who has cancer becoming confused when the surgeon recommends surgery and the radiologist recommends radiation. There are also the economic interests of the hospitals and doctors. When the hospital invests in an expensive new machine, there is a powerful incentive for doctors to refer more patients to that treatment. Dr. Eddy calls this “supply driving demand,” instead of the other way around. There is also a cultural bias in the U.S. that often finds patients mistakenly thinking the most expensive and aggressive procedure is the best.
The randomized clinical trial has historically been the gold standard for medical research. Some are now questioning that model. The trials take years and cost millions of dollars. By the time the results come in, science may have moved on, making the findings of little relevance. People come to studies with complex combinations of medical diseases and problems, making it difficult to study a single disease or a single treatment. And on top of all that, patients often don’t stick with the programs they are assigned. Is it any wonder that about one-third of all clinical trials lead to conclusions that are later found to be false?
There are plenty of areas in medicine (vaccinations, early detection of certain tumors, etc.) where the benefits are clearly known, but the vast majority of medical options do not always have well-documented outcomes. Dr. Eddy would like both patients and doctors alike to be able to more clearly understand and discuss the uncertainties of many medical procedures, which account for about 75%-80% of medical treatments.
Dr. Eddy believes strongly the computer model he is working on holds promise to guide medicine to more evidence-based practice. Currently he says the model is like the “Wright brothers’ plane” but in the future the computer model will be able to offer “transcontinental flights.”
Source: “Medical Guesswork,” cover story of Business Week online. May 29, 2006.
Compiled by Betty Holmes, MS, RD, Senior University Extension Educator, University of Wyoming; bholmes@uwyo.edu