HOW OFTEN DOES BEST PRACTICE IN MEDICINE CHANGE?

HOW OFTEN DOES BEST PRACTICE IN MEDICINE CHANGE? This article by two Harvard Medical School professors reports on a surprising study. (The link seems unreliable. The article is by Jerome Groopman and Pamela Hartzband in the Wall Street Journal for August 31.) How long does it take for “conclusions derived from clinical studies about drugs, devices and procedures to become outdated”? A Canadian study in 2007 found that: “Within one year, 15 of 100 recommendations based on the “best evidence” had to be significantly reversed; within two years, 23 were reversed, and at 5 1/2 years, half were contradicted.” An intuitive way of phrasing the result is that the half life of current best practices is less than six years. I have no other information about the study, but it does reflect how rapidly medical knowledge changes and how tentative many conclusions are. Doctors have to act on imperfect knowledge. (I found an article by Michael Barone which quotes the key paragraphs of the Groopman and Hartzband article. Ironically, Barone concludes: “Comparative effectiveness research may very well be useful. But to standardize medical treatment on the basis of comparative effectiveness research seems like the height of folly.” I am wholeheartedly in favor of much more comparative effectiveness research—which should be made available to doctors just as other medical research is made available. I would take the study as supporting the need for more comparative effectiveness research.)