Tree of Life – the first-known sketch by Charles Darwin of an evolutionary tree describing the relationships among groups of organisms (Cambridge University Library).
The Merriam-Webster Dictionary defines science as:
Knowledge about or study of the natural world based on facts learned through experiments and observation.
Knowledge as distinguished from ignorance or misunderstanding.
While this should distinguish science from pseudoscience, those who practice the latter often lay claim to the same definition. But one of the major differences between science and pseudoscience is that science advances through constant rejection and revision of prior models and hypotheses as new evidence is produced; it evolves. This is the antithesis of pseudoscience. At the heart of pseudoscience-based medicine (PBM) is dogma and belief. It clings to its preconceptions and never changes in order to improve. It thrives on the intransigence of its belief system, and rejects threats to its dogma. Despite the constant claims by peddlers of pseudoscience that SBM practitioners are closed-minded, we know that, in fact, PBM is the ultimate in closed-minded belief. Of course, those of us who claim to practice SBM aren’t always quick to adopt new evidence. We sometimes continue practices that may once have been the standard of care but are no longer supported by the best available evidence, or perhaps may even be contradicted by the latest evidence. Often this is a byproduct of habituated practice and a failure to keep current with the literature. While this is certainly a failure of modern medicine, it is not an inevitable outcome. It is not emblematic of the practice of medicine, as it is with PBM. When medicine is science-based, it strives for continual improvement based on modifications around emerging evidence. (more…)
The term “evidence-based medicine” first appeared in the medical literature in 1992. It quickly became popular and developed into a systematic enterprise. A book by Ulrich Tröhler To Improve the Evidence of Medicine: The 18th century British origins of a critical approach argues that its roots go back to the 1700s in Scotland and England. An e-mail correspondent recommended it to me. Can’t remember who, but I would like to thank him.
Francis Bacon (1561-1626) differentiated between “ordinary experience” (chance observations) and more objective “ordered experience” (methodological observations). Both of these involved empirical knowledge. It’s hard to get back into the mindset of his time, when most physicians rejected empiricism as the sphere of quacks and surgeons. Tröhler helps us understand why they did:
…since antiquity, the mark of distinction of a learned man had been the certainty of his knowledge. A doctor knew — he did not need to test his kind of knowledge empirically because this would imply acknowledgement of uncertainty.
That was the question asked on a Medscape Connect discussion
I did a double-take. How do you feel? Could anybody object to the idea of basing treatments on evidence? The doctor who started the discussion asked:
Besides using EBM, a lot of my prescribing comes from anecdotal experience and intuition. How about you? Where do you get your information from that you use to treat your patients? Do you always ascribe to EBM, or do you deviate from it with certain medical conditions/patients?
I had naively thought that my profession uniformly embraced EBM. How could they not? The commenters broke my bubble big-time. Some of them summarily reject EBM… although it appears that what they are rejecting is not what I understand EBM to mean. (more…)
Mark Tonelli, MD has problems with evidence-based medicine (EBM). He has published a few articles detailing his issues, and he makes some legitimate points. We at science-based medicine (SBM) have a few issues with the execution of EBM as well, so I am sympathetic to constructive criticism.
In an article titled: Integrating evidence into clinical practice: an alternative to evidence-based approaches. The abstract states:
Evidence-based medicine (EBM) has thus far failed to adequately account for the appropriate incorporation of other potential warrants for medical decision making into clinical practice. In particular, EBM has struggled with the value and integration of other kinds of medical knowledge, such as those derived from clinical experience or based on pathophysiologic rationale. The general priority given to empirical evidence derived from clinical research in all EBM approaches is not epistemically tenable. A casuistic alternative to EBM approaches recognizes that five distinct topics, 1) empirical evidence, 2) experiential evidence, 3) pathophysiologic rationale, 4) patient goals and values, and 5) system features are potentially relevant to any clinical decision. No single topic has a general priority over any other and the relative importance of a topic will depend upon the circumstances of the particular case. The skilled clinician must weigh these potentially conflicting evidentiary and non-evidentiary warrants for action, employing both practical and theoretical reasoning, in order to arrive at the best choice for an individual patient.
For most of human history, doctors have killed their patients more often than they have saved them. An excellent new book, Taking the Medicine: A Short History of Medicine’s Beautiful Idea, and Our Difficulty Swallowing It, by Druin Burch, MD, describes medicine’s bleak past, how better ways of thinking led to modern successes, and how failure to adopt those better ways of thinking continues to impede medical progress.
The moral is not that doctors once did foolish things. The moral is that even the best of people let themselves down when they rely on untested theories and that these failures kill people and stain history. Bleeding and mercury have gone out of fashion, untested certainties and overconfidence have not.
Burch’s conversation with his rowing coach epitomizes the problem:
“I want you to keep your heart rate at 85% of max for the next hour and a half.”
“Because it’s the best way to improve your fitness.”
“How do you know?”
“Because I’ve done it before and it worked. Because that’s what the people who win the Olympics do. I know, I’ve trained some of them.”
“But has anyone actually done an experiment?”
“What on earth are you talking about?”
This book is Burch’s answer to his coach’s question. Medicine’s “beautiful idea” is that we should test all hypotheses and beliefs using the kind of tests that are reliable for determining the truth. Instead of going by tradition, authority, theory, common sense, or personal experience, we now have effective tools to find out for sure whether a treatment really works. (more…)