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BLOG: February 2007
Evidence-based medicineIt may be hard to believe, but the idea of evidence-based medical practice (also, "scientific medicine") - in the sense of relying on the actual performance data - has been soundly formulated as little as 35 years ago (Archie Cochrane's 1972 book). An article in the Time magazine (February 2007) addresses its importance and controversy.
What is it that makes evidence-based medicine (EBM) important to an ordinary person like you and I?
Does the "evidence-based" title of this new medical approach mean that "regular" medicine ignores evidence? Not really. But medical evidence can be anything from more or less limited clinical experience of individual medical practitioners, to a drug manufacturers' pre-marketing study - neither proven very reliable - and to large and small post-marketing trials.
It is mainly the first two forms of evidence that dominated before evidence-based medicine recognized large randomized controlled trials as a single most reliable indicator of efficacy.
In other words, what EBM has changed in medicine is introduction of the
"evidence quality" criteria.
What this means to you is that whenever you are being recommended certain treatment, you ought to ask about quality of the evidence the recommendation is based on. While there is more than a single possible categorization, evidence quality generally ranks as follows, top to bottom:
● large randomized controlled trials - properly designed - followed by
● non-randomized trials and smaller group studies, with the
● opinion of respected authorities based on evidence other than the above two, trailing at the end.
Beware of poorly designed trials and studies. Not seldom they are purposely manipulated in order to give desired result. Notorious example are pre-marketing studies by drug manufacturers, as well as studies financed by an "interested party". Recent widely publicized "studies" alleging that use of antioxidants invites death, or "slightly" higher risk of prostate cancer for those who use (unspecified) multivitamin more than once a day, may have been constructed by computer scanning past statistical data and selectively aggregating such data sources within which a certain (negative) outcome is higher due to some other, hidden factors.
Often times, the media uses such a piece of questionable information for sensationalistic headlines.
Opponents of EBM say that it unduly demotes individual aspect, both, that of practitioner and of patient. In other words, that what is good - or not good - statistically (for a large group of people),
is not necessarily so for the individual patient.
This would be, actually, great point, if it only wouldn't be used so selectively. The fact is that the entire allopathic medicine is guilty of that sin, by choosing to treat the symptom, rather than the patient.
That brings us to the main point: even if your suggested therapy is supported by first-grade evidence, it doesn't mean you should go along and accept it for that reason alone. It still may not work for you, and might even make things worse. What you need is a therapy based on your
biochemistry, lifestyle, environment
This is where true medicine should be heading.
Statistical medical evidence has just as much of individual applicability as any other statistical data: none. Its real function is in determining group response, or effectiveness. Its real value is in debunking deadly errors of the shot-in-the-dark symptom-treating same-for-all medical practice. By exposing only the two of its big blunders - hormone replacement therapy and anti-arrhythmia drug Tambocor - in independent post-marketing studies, it has already saved many thousands of lives.
As long as symptom-treating business-minded medicine dominates, evidence-based medicine will be for many making the difference between life and avoidable suffering and death.