Robert Centor illustrates the problem as The conundrum of clinical medicine is what makes it difficult.
The term, “evidence-based medicine” (EBM), provokes strong feelings from its proponents and its skeptics. I spent a full day recently in discussions about EBM. As the day proceeded I understood that evidence is wonderful when it fits the clinical question, but that too often the clinical question does not, and probably will not have adequate evidence.
Even if one believes in EBM, controversies among guidelines must give one pause. These likely occur because differing guideline committees have differing priorities and values. Data are not cold hard facts that we can always apply to our patients. Rather we must filter data through a screen of patient preferences, co-morbidities and social concerns (including money).
Evidence, i.e. what can be observed and measured, has both proponents and skeptics and is a matter of belief in the medical community? That is (or should be) scary.
What is also scary is the really bad science education in the discussion. Evidence is based on measurement and that always comes along with a proper consideration for precision and accuracy. And both of those concepts consider the impact of the conditions of the measurement. When Centor talks about EBM and its fit to a clinical question, he ignores these measurement issues and tries to create a straw man making a complex scenario into a binary measure.
The comment about “filter data” tells of an effort to squish evidence into a small hole, a subset of measures that have specific numeric results. The issue in medicine has been, for the last century or so, that of trying to find objective and repeatable measures for the many situations a practicing encounters. It is one of trying to decipher the evidence and the models that were once just the province of gifted practitioners to the realm where they can be understood and applied by the less gifted.
Why this is an issue is that medicine has been plagued by those who eschew evidence and use a longing for a cure and the issues in measurement and knowledge to sell their snake oil.
Another example in clinical medicine where evidence gets short shrift is illustrated in the medical establishments efforts to bring gun control into their realm. If a sign on a local clinic was taken seriously, patients would need to leave their pocket contents at home and park canes and other assistive devices outside the clinic. The medical profession has taken leave of their charge to examine the person in favor of putting a focus on the tools their patient uses. This makes the false assumption that the tool is used for only one thing and, from that, concludes that the patient is mentally unhinged (but can be re-hinged by a sign on the door). Evidence and intellectual integrity go out the window.
Clinical medicine is difficult because it deals with interacting complex systems that are neither fixed nor consistent in their behavior. That requires a respect for evidence coupled with a proper understanding of measurement and a good awareness of what is known and what is not.