In a recent article entitled “A Hayekian Defense of Evidence-Based Medicine” Andrew Foy makes a thoughtful attempt to rebut my article on “The Devolution of Evidence-Based Medicine.” I am grateful for his interest in my work and for the the kind compliment that he extended in his article. Having also become familiar with his fine writing, I return it with all sincerity. I am also grateful to the THCB staff for allowing me to respond to Andrew’s article.
Andrew views EBM as a positive development away from the era of anecdotal, and often misleading medical practices: “Arguing for a return to small data and physician judgment based on personal experience is, in my opinion, the worst thing we could be promoting.” Andrew’s main concern is that my views may amount to “throwing the baby with the bath water.”
On those counts, I must plead guilty as charged. I have been trying to sink that baby for a number of years now, attacking it from a variety of angles. I have made a special plea in favor of small data and I have even questioned the intellectual sanity of EBM. On the question of the coexistence between EBM and clinical judgment, I have been decidedly intolerant, relegating EBM to second class citizen status. In other words, I’m an unapologetic EBM-denialist which, as I found out yesterday on Twitter, puts me in the same category as climate change skeptics.
My main concern today, however, is to address the relationship between EBM and the free-market, and to reject Andrew’s point that EBM is somehow compatible with it. First, though, let me say that in no way do I deny the notion that American medicine has, for decades, harbored practices of highly doubtful benefit to benefit to patients, and that many such practices may, in fact, have been dangerous or harmful. I am fully on board with any effort to eradicate “eminence-based medicine.”
But before we reach out for an EBM solution to that problem, perhaps we should first wonder about causes. What keeps the errors of eminence-based medicine persisting for so long? Why do patients and doctors remain so wedded to a course of therapy as to blithely engage in unbeneficial or even harmful care?
If I read Andrew correctly, he seems to believe that these errors persist because outcome uncertainties are inherent to clinical care, hence the need for EBM. But that cannot be the fundamental reason. Why would patients continue to pursue a treatment for which they have neither objective nor subjective tangible benefit? Why wouldn’t they refuse to go along? After all, many of them do exercise their ability to be non-compliant in the case of treatments deemed beneficial to them according to the truths of EBM!
Outcome uncertainty, then cannot be the reason why futile or harmful treatments persist, and if outcome uncertainty is not the reason, reducing it by way of EBM may not be the answer either.
What eludes Andrews is that eminence-based medicine is not simply the result of individual doctors exercising judgment with limited knowledge. Rather, eminence-based medicine happens when doctors apply their own pet theories and disregard the needs and wants of the patient at hand.
By missing that point, Andrew misses that eminence-based medicine is precisely minimized by the free-market and, on the contrary, encouraged by government intervention. The history of American medicine provides ample examples to make that point.
In the late nineteenth century, healthcare in the United States was uniquely unregulated. Yet, contrary to common belief or fabricated myths, care was improving by leaps and bounds, getting at once better, cheaper—and more scientific. It is during that time that some of the finest medical institutions emerged, including the Mayo Clinic and the Johns Hopkins Hospital. Sure, there were snake oil salesmen, but these were by-and-large being driven out of business by a growing community of serious, well-trained, and effective physicians. And competition among these practitioners kept them humble and at the service of patients.
All of this changed in the 1910’s when, following the Flexner reforms, state licensing laws were enacted. It is in the heels of these laws that medical paternalism emerged.
As an illustration, consider this passage excerpted from an official report published soon after the enactment of licensing laws:
The physician is the outstanding practitioner of medicine. The need and the value of his service sets him above all others. He alone, of all types of medical practitioners in the United States, is permitted by law to diagnose and treat all diseases and conditions and to use (with certain minor exceptions) any form of diagnostic or therapeutic technique which he considers necessary, desirable, and within his professional skill. (Report of the Committee on the Cost of Medical Care, 1928, p. 195)
From that point onward, medical abuses of privilege became much more widespread than they had been.
Furthermore, as Kenneth Ludmerer has pointed out, this elevation of the physician to the status of demi-God by government fiat went hand-in-hand with the rise of the academic ivory tower, since academic medical schools were producing the “cream of the crop” among doctors. Academic ivory towers, naturally, become common sources of practices founded on eminence.
Of course, licensing laws and the emergence of the ivory towers are not the only factors to consider. Other government interventions soon followed to bring about systems of third-party payment for medical care—health insurance. Without these government interventions, and without the existence of licensing laws, it is unlikely that health insurance would have emerged from the free market. By unmooring medical decisions from any financial constraints, health insurance contributes immensely to the perpetuation of eminence-based practice.
It is this regulatory context, then, that is at the root of eminence-based medicine, and not the uncertainties of clinical care which, in a profound way, are inherent to the medical encounter.
Andrew believes that EBM discovery is akin to price setting on the free market. I strongly disagree with that analogy. As Andrew himself has noted, prices set in the free market convey consumer values and are the end results of myriad decisions made on the basis of dispersed knowledge.
EBM results, on the other hand, are statistical relationships between interventions and outcomes which are carefully selected by investigators in highly contrived experimental settings. In these settings, the choices and preferences of doctors and patients are ignored or neutered by design in order to isolate the relationship of interest. Any value obtained as a result of an EBM experiment is primarily imputable to the investigators or sponsors, and only secondarily (and statistically) of benefit to patients.
EBM is no free market phenomenon. EBM is an academic invention incubated in Canada, a country with a single-payer healthcare system! As I described in my article, this invention has spun out of control and has turned EBM into a weapon wielded with equal vigor by the pharmaceutical industry, by regulators, and by those who aim to equalize the historical excesses of eminence-based medicine through the dubious doctrine of “Less-Is-More.” None of these movements, it seems, are motivated by a desire to advance a genuine human science that is meaningful to individual patients. In fact, to the extent that is a pet theory which standardizes care for entire populations, EBM is eminence-based medicine on steroids.
But if EBM is by no means a product of the free market, can the free market address our need to improve therapeutic predictions or will it set us back to a clinical stone age?
So long as narrowing clinical outcome expectations is truly desired by doctors and patients—and there is no reason to doubt that it is—then the free market is demonstrably the optimal environment that can allow human ingenuity to devise clever ways and methods to achieve that goal. But what shape or form would those methods take and how closely would they resemble what we now take to be evidence-based science, I have no idea. If I believed I held that knowledge, I would be repudiating Hayek.
Michel Accad is a cardiologist who practices in San Francisco. He blogs at Alert and Oriented and can be followed on Twitter @michelaccad
Brilliant blog post, whose author will be shown, in the future, to be on the right side of history. While medicine moves towards more standardization, the realities of the marketplace move towards more customization, which is the complete opposite direction.
For all 7 billion people on the earth, there are 7 billion unique optimal paths to cure/wellness. Technology is enabling this change, and this clash between the “mainstream system” and the marketplace is only going to become more pronounced as time goes on. Things like Predictive Medicine, Individualized Medicine, etc.
The strange thing is, there’s an assumption among his opponents that 1-to-1 customization somehow means non evidence-based. The opposite is true …. people are sidestepping the HC system entirely to do self-diagnosis and self-treatment. I think the problem stems from most doctors’ feeling that anecdotes are worthless, which is incorrect. Anecdotes, in sufficient quality and quantity, have evidentiary value. And patients are using them all the time now to out-perform doctors in both diagnostic accuracy and treatment efficacy (e.g. patients using cannabis oil to treat and cure cancer).
So it really comes down to his opponents’ definition of “evidence” …. so in that sense, the blog author’s title is mis-named …. it should say “A repudiation of the science from centralized authorities as the only good source of evidence”. Patients are (along with a few types of doctors like Functional Medicine doctors) moving, on their own, using collaboration technology, towards *more* evidence-based medicine, not less. Less standardization does not mean less use of evidence. It just means a culture clash between doctors’ control of what ‘Evidence’ means, and what the marketplace is going to force it to mean. Doctors will lose this battle.
For me, it is not one or the other but rather the mash up, a constant improvement based on man and machine(data), eminence and evidence, we should be working towards. All to often I’ve watched data driven care algorithms lead to bizarre decisions by providers. Alternatively, we learn how to practice as medical students and residents with little feedback on how these eminence driven decisions really effect the majority of our patients. Often our last great mistake driving treatment choices.
Evidence based medicine drive eminence based decision making. However, historically the evidence has been limited often very small trials where the conclusions get generalized to dogma.Results are reported through the eyes of providers and typically fail to incorporate patient reported outcomes. For evidence to truly be of value, the patient’s view should be considered along with those of providers.
While I may quibble with Michel about there being value in evidence based medicine, the most salient point Michel makes well is that the proliferation of evidence based medicine by no means has extinguished eminence based medicine. Rather, there is ample evidence to suggest ebm has been hijacked and used by a variety of interests who have no interest in science or patients. Regulators who see waste everywhere generate data to suggest less is more while industry generates data to show that more of their product is more. Physicians faced with this mass of information must use their
Judgement and their reasoning (yes still needed) to decide what to do to the individual patient sitting in front of them. Michel calls for throwing it all out, but surely there is some value there. There is a reason, for instance, that we don’t use alpha-blockers for hypertension as first line agents. This ‘edict’ came from a Canadian sponsored randomized control trial. There is no doubt that algorithmic, protocol driven medicine is hopelessly flawed, but ignoring all ebm doesn’t just blue the path, it obliterates
It. I need some path.. Even if we can’t agree where the path is
going :). This argument would benefit from nuance. To say there is benefit in small data, does not imply there is no value in big data. The truth, in this case, lies in a nuanced approach which sees value in things big and small.
Thank you, Anish.
Whether or not to use EBM results in bedside clinical decision making was not directly the subject of this article. Envisioning making decisions without EBM is extremely difficult because we are so conditioned by its existence. Also, the rise of EBM rests on certain incorrect assumptions about health and disease that also condition our thinking. Discussing all of that would take us too far afield, but I certainly believe that a good physician would be able to manage patients perfectly well even without the ALLHAT trial. Or, putting it in another way, if medical decision-making is properly understood, the added value of ALLHAT would be trivial.
I think that outcome expectation you mention–narrowing–is gping to be forgotten. There is too much variation in the underlying molecular machinery. Just consider: we have 23,000 protein coding genes and even more that are not coded and make only RNA (predominately for ribosomes). Each of these is transcribed at a different rate in different people. Eg we might transcibe ten a minute in John and 12 in Peter. Transcription variation is only one process wherein there is variation.
If you like to see narrowing of outcome then you would like ten artists, all viewing Half Dome, to arrive at the same picture after an afternoon of sketching. Not going to happen…and why would that be desireable?
This is the canonical mistake that policy people make:They are trying to allocate a service that is partly–maybe mostly?–artistic at this stage in its evolution. The fraction what we know divided by what we don’t know is an infinitesimal.
You seem to be more of a Luddite than I, Dr. Palmer! Kidding apart, I tend to agree with you that the variability is astounding and all-too-often overlooked. Nevertheless, certain things do work and knowledge has gotten better. My point is that true scientific value can only be achieved if we let patients demonstrate what they want and is important to them, i.e., in unhampered healthcare relationships.
This whole medical business is really early–in the Pre-Cambrian era. We don’t want standarization too much or we’ll freeze primative thinking. We still don’t have any RDBCTs on treating sarcoid, common ‘ol sarcoid. This is because it has become standard practice to use steroids and we can’t form a control arm of the trial because it would be malpractice not to so treat with nothing or something else. So we are stuck. Look at the era when we were doing so many pulmonary artery caths for wedge and PA pressures. Aren’t you happy we did not standardize all this invasive stuff? You know the first non-sail and non-oar powered boats used a long Archimedes screw fasted to the keel. [sic!] Performance sucked. One day the screw broke in half and the performance miraculously improved, Thus, the invention of the propeller. You would not have wanted humanity to go on forever trying to improve the Archimedes screw, would you? Huh?
“You would not have wanted humanity to go on forever trying to improve the Archimedes screw, would you?”
William, one is a boat, the other is peoples’ lives subject to experimentation with no understanding of what may work and what may not. Informed consent is not really informed, especially when the doc does not have all the information. That’s why we put innocent animals through “let’s see what happens when” experiments, and not humans.
“EBM is an academic invention incubated in Canada, a country with a single-payer healthcare system!”
OH MY GOD! I did notice the exclamation point in that, “run for your lives” statement.
So, are chiropractors EBM or snake oil salesmen?
I too am having a hard time understanding your point, other than government is evil. Is it necessary for medical practices to undergo peer review?
That sentence was written in response to the parallel Andrew made between EBM and price setting in the free market, hence the exclamation point.
I’m trying to grasp your message but can’t. Your characterizations of EBM are upstream and lofty and I am failing to see what you are doing at the bedside that supplants EBMs approach to medical problem solving.
Really, after reading what you wrote, I get the feeling if I use an LR or apply bayesian thinking around an RCT, my next stop will be the gulag.
The links you embed reference texts. I will have to take your word those works convey what you are relaying–but those are assumptions.
This piece focused on the relationship between EBM and free-market principles, in reply to Andrew’s article, but let me address your point about decision-making in general. We are so conditioned into thinking about decision-making in terms of risk calculation that I am not surprised my position seems so odd to you and, I’m sure, to many readers.
It is my firm belief, however, that when it comes to decision making, risk calculation is a metaphor and not the reality of what takes place. The mind is not a computer and decisions are not calculations. I have written extensively about medical decision-making on my blog, but I also refer to the works of many others, notably Gary Klein. And yes, I do realize that I link to their texts, and that if you are unable or unwilling to read those texts, you have to take my word for conveying what they say, but I’m not sure how to overcome this for you…Isn’t that how scholarship works?
If you are interested, below is a link to my posts on medical-decision making, as well as a link to a post that contrasts Gary Klein’s work to the work of Daniel Kahneman who, in my opinion, represents a more mainstream and EBM-friendly view of decision-making. I am by no mean the first or only critic of EBM. You may want to check out the work of Alvan Feinstein (who, as the grand-daddy of clinical epidemiology, cannot be accused of rejecting quantitative methods), Sandra Tanenbaum (see her NEJM paper entitled “What doctors know”, 1992, I believe), Kathryn Montgomery, and many other scholars vastly more qualified than me.
PS: Rest assured, libertarian gulags are inconceivable 🙂
I have read some of your posts. I still feel the same way. I don’t doubt your intellect (it’s impressive, and your grasp of economics and philosophy exceeds mine), but whenever I finish one of your posts I don’t feel it has helped me in any way with what I have to do at the bedside to make good or better decisions.
You do say something I noted–the mind is not a computer.
However, I use calculators, just for the reason you cite.
Thanks, Brad, and if I fail to convince you, that is certainly my problem. However, I would like you to at least entertain the thought that the welfare of your patients could be served just as well, if not better, even without the crutch of risk calculators. After all, these apps only emerged in the last few years. Were all generations of doctors practicing up until then shooting in the dark? Somehow, I find that hard to believe. “Decision = Calculation” is the current orthodoxy in medical school and residency. It has a simplistic appeal and I have my work cut out for me if I want to change people’s minds about it 🙂