Friday, January 5, 2018

Evidenced Based Medicine, another look.


I want to re-visit the concept of Evidence based medicine. Its got its own acronym, EBM and is the basis for scientific, Western Medicine. Everyone agrees it’s the best system. Well … not everyone.  There is also something called science based medicine.  As I recently read, EBM is a subset of science based medicine. EBM is a paradigm in and of itself.  Paradigms are inherently flawed constructs and ultimately fold or mold as science marches on. A work product of EBM is the manufacture of guidelines. 
The Institute of Medicine has proposed metrics for assessing guidelines. Some of these include the following:

1)     All potential biases and financial conflicts of interest must be listed.
2)     Different medical specialties should contribute to the guidelines so that a “blind-spot” of a particular sub-specialty go unaddressed.
3)     There should be a period of public comment before guidelines are advanced.
4)     Political biases should be taken into account
5)     Patient preferences should be considered
6)     Input from other ancillary medical fields and alternative fields be considered
7)     There needs to be in place a mechanism for ongoing correction - adjustment as information changes.
8)     It should be recognized that the “evidence” in support of many guidelines is weak.
9)     Guidelines are to help doctors do a better job and not to be the basis of insurance company denials and/or Medical Board investigations. Guidelines are voluntary, not the law.
10)  Guidelines should not be used for “cook book” medicine. Patients are all different. Different genetics, comorbidities etc. 
11)  The expanding role of personal medicine must be recognized.

Evidence is graded. Some of this evidence is very weak and/or subjective but it still valued in the EBM paradigm.
The IOM points out that in 2017, according to the IDSA, only 14% of its guidelines for 400 diseases is based on strong evidence. 
My source is UpToDate, the most widely used web based text/resource used by physicians around the globe. 
There are very thoughtful academics who have a clear appreciation of the pitfalls of EBM and guidelines. 
Evidence based medicine holds up the blinded randomized control study as a gold standard. The studies are frequently subjected to statistic machinations, especially the metanalysis. Medical studies may be flawed, fatally so at times and in many ways. Some problems include: investigator bias, patient selection bias, study cohort poorly chosen, poor choices of study treatment/intervention, poor endpoints chosen, poor understanding of the disease, over generalization of results, improper use of statistics, a blatant disregard for other points of view and a supercilious view of other investigators. For example, the last, highly touted placebo-controlled NIH-sponsored study was published in 2007 (Fallon).  IDSA “experts” disregarded the views of the lead author, positing their own biased views.  Other EBM sources are reviews of literature, expert opinion, case studies and uncontrolled studies. Somehow, guidelines, not part and parcel of the EBM level of evidence have become accepted as “evidence.” Evidence is a collection of facts, reports and opinions. This is not the same as proof.  What is given no role in the hierarchy is SCIENCE. Plausibility. Basic science reveals details on a molecular or test tube basis.  This sort of evidence can be very instructive.  For example, to date, multiple studies have demonstrated that Lyme has never been eradicated in any of the 3 animal models and that Lyme is nearly impossible to eradicate in a test tube.  Nevertheless, based on “evidence,” experts insist Lyme is easily eradicated with 3 weeks of doxycycline in virtually all humans. The experts are subject to Paradigm Bias -- leading to certain false and inevitable conclusions.  When higher level Science is considered in the calculation, the conclusions are clearly absurd. 
When weak evidence, including poorly done studies and expert opinion becomes the “truth” then the EBM model may be twisted, leading to pseudoscience – or anti-science.  
Chronic Lyme disease advocates have been repeatedly called Anti-science.
A wise man once told me:  watch what they accuse you of – that’s what they are up to.    
I have railed against EBM in part because it has been weaponized against me.  Evidence based medicine is a tool. It is a work in progress.  Science leads us to truths – but only partial truths - because there is always more to learn.  Evidence based medicine surely fails when it does not distinguish between fact and theory, hypothesis and truth.  Scientists pursue knowledge using time-honored methods. The methods are always imperfect and may get incorrect results. Science searches for fundamental truths about the world we live in. Science is motivated by curiosity. A desire to know. Science asks questions and seeks answers. With every answer many more questions inevitably arise. Only an arrogant fool thinks he has all the answers.  
A word about empiricism. There is much for Western Doctors to learn from ancient traditions of healing from places like China, India, the Americas and remote tropical jungles. I don’t know how acupuncture works, but it works on dogs and as far as I can tell, dogs aren’t subject to placebo effects. Science doesn’t insist the therapies are ineffective. Rational scientist can apply inductive reasoning and deductive reasoning and have open minds. It is the job of science to figure out why the therapies work. It is impossible to judge plausibility when the mechanism is unknown. Physicians and scientists should have a healthy dose of skepticism but also an open mind.  Closed minds are impossible to pry open.  As Einstein tells us. Imagination is much more important than knowledge.  Knowledge is limited and imagination is not. 
I like EMB (with science based medicine) – when it is understood within context and properly applied; when science, plausibility and common sense are valued; when bloated egos are removed from the equation; when its flaws and limitations are taken into account; when guidelines are properly applied and most of all, when its methods are applied with intelligence and thoughtfulness.




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