Archie Cochrane and the Early Days of Evidence-Based Medicine: Seeing Medicine through the Eyes of Philosophy
Everything that we do today in science and medicine has a history. Some practices, views, and philosophies have their origins in social movements. Of particular interest to me is the movement of evidence-based medicine (EBM). For some it is seen as a bulwark against alternative medicine, of which chiropractic is often placed into that category. My goal in this essay will be to briefly discuss the EBM movement’s origins, with a specific focus on Archie Cochrane. I intend to follow this essay with a multi-part series on evidence-based chiropractic and a set of arguments that have arisen surrounding the Global Summit, an international conference to evaluate chiropractic’s efficacy for non-musculoskeletal conditions. Until I find more free time to analyze these movements thoroughly, I see it as foundational to explore EBM’s beginnings, for it is in tracing its historical and philosophical foundations that it can be better understood. This will be crucial to any readers’ understanding of subsequent essays or general knowledge on current standards of evidence evaluation.
To discuss the history of EBM requires us first to make a critical philosophical assumption implicit in the following question: is EBM something that a physician does, or is it a movement that prescribed what “evidence-based practice” is? In other words, should EBM be seen as a social movement, or is it something that an individual can approach? To those that have studied any philosophy of science, you will quickly recognize that I am asking the same question most mid-20th century philosophers of science asked: should we be seeing science as a social entity or should it be seen as something approachable by the next Francis Bacon? I will take the path that modern philosophy of science has taken, a road leading me to admit the obvious….science and medicine are embedded within the social world. While individuals may perform science and medicine, the respective community weighs the evidence to determine the next step forward. Said differently, through social means, we gather information, have our ideas critiqued, and generate knowledge. As much as EBM was a movement developed in individuals, it became a sociocultural force in medicine. As such, it deserves to be described, studied, and viewed as a movement.
The next step in assessing EBM as a movement is categorizing it as a type of social movement. Within philosophy and sociology, there has been considerable work on social movements, their origins, and ways to categorize them. The framework that is likely to be the most useful is David Arbele’s. His framework separates movements based on scope and extent. Scope refers to the amount of change suggested by the movement, extent refers to who is the target. A reproduction of the framework is shown below:
Within this framework, EBM can be identified as a “reformative” social movement. Medicine itself is not asked to change significantly. Rather, the types of evidence that medicine relies upon are asked to shift. Regarding the extent of this change, it is frequently prescribed as a broad philosophy that all medical society should embrace. While it could be considered an alternative movement, it is difficult to justify that individual or group behavior alone are the targets. Instead, one can see that EBM strives to transform how clinicians think about evidence in practice. It is not phrased as “those of us in EBM will embrace this philosophy, the rest of you continue on,” instead, there are frequent callings for medicine to look at its use of evidence and switch away from an overreliance on the biological mechanism and clinical expertise.
Regarding the history of the movement, EBM, as it is known today, arose from a few select “hotspots.” Over in Scotland, we have Archie Cochrane, who published “Effectiveness and Efficiency: Random Reflections on Health Service” in 1972, one of the works that would give rise to EBM orthodoxy. Cochrane’s life was diverse, full of travels and medical experiences that concerned him. Of note, he struggled with the treatment of tuberculosis and his illness: porphyria. This personal and clinical experience contributed to his views on the state of medicine at that time….it had little evidence to back its claims. What was his solution to this? The randomized-controlled trial. As a review in the BMJ written by CT Dollery would state: “the hero of the book is the randomized control trial (RCT), and the villains are the clinicians in the “care” part of the National Health Service (NHS) who either fail to carry out such trials or succeed in ignoring the results if they do not fit in with their preconceived ideas.” Although such a description of Cochrane’s seminal work may be overly simplified, it is not overtly misleading. Cochrane’s main goal in publishing this work was to elevate the RCT to a pinnacle.
It is essential to understand that this issue becomes central for the “Founding Fathers” of EBM. They are pushing against clinician opinion, observational studies, and certainly the medical culture of their day. This is the area where philosophy of medicine can enter, providing critiques of their early work, and ultimately helping us understand these hierarchies. For this criticism, I recommend seeing this work by C.J. Blunt: Random Reflections: Cochrane and the Origins of Hierarchies. His essay focuses on Cochrane’s views on the RCT, which can easily be summarized as evidence is either “RCT or bunk.” Interestingly enough, this does not match with Cochrane’s concluding statements regarding the value of the RCT, which are reproduced below:
“In writing this section in praise of the RCT, I do not want to give the impression that it is the only technique of any value in medical research. This would, of course, be entirely untrue. I believe, however, that the problem of evaluation is the first priority of the NHS and that for this purpose the RCT is much the most satisfactory in spite of its snags. The main job of medical administrators is to make choices between alternatives. To enable them to make the correct choices, they must have accurate comparable data about the benefit and cost of the alternatives. These can really only be obtained by an adequately costed RCT.”
It is quite obvious here that Cochrane is attempting to smooth out an emphatic statement that an “adequately costed RCT” is the best way to obtain the answer on effectiveness. He qualifies it by weakening it from an “only RCTs should be trusted” to “RCTs are the best, but not the only.” Within this distinction, you have the subtle origin of EBM’s hierarchy of evidence as there is an implicit ranking according to study type rather than quality. Today there are over 195 hierarchies of evidence, all built from these original assumptions of the founding fathers, of which Cochrane remains fairly central. As they intended, EBM transformed the landscape of medicine and the pathway to regulatory approval of a pharmaceutical. One could, with tongue in cheek, proclaim EBM a certain orthodoxy. As in religion, orthodoxy has its dissenters, amateur and professional alike. Within philosophy of medicine many have criticized the RCT and its stance at the top of the hierarchy. Others extend such criticism to the hierarchy itself. One such philosopher is C.J. Blunt. His 2015 thesis and subsequent work have been dedicated to this topic, driving home the point that these hierarchies require justification.
My reading of C.J.’s work reveals a philosopher in favor of a more pluralistic approach to evidence. As I do not intend on a complete characterization of his arguments in this essay, I will overly simplify it as the following statement: hierarchies are falsely advertised as the solution to evidence problems in medicine. It can be argued that instead of helping us describe how much evidence there is, the extent of a treatment’s effect size, and its applicability to the real world, we are left with a ranking of evidence-based on study type. This limits our attempts at fully characterizing the evidence quality. For example, what if you only have one RCT that is of high quality? Can it suddenly be used to make broad policy recommendations? I use this example because it is exactly what is claimed by Goertz et al. in their recent paper, “Extrapolating Beyond the Data in a Systematic Review of Spinal Manipulation for Non-musculoskeletal Disorders: A Fall From the Summit” published in 2021. In this paper, Goertz et al. quote from C.J.’s 2015 thesis, using it as justification for their refusal to stand behind the Summit’s paper produced at the Global Summit on the Efficacy and Effectiveness of Spinal Manipulation for the Management of Non-musculoskeletal Disorders (Global Summit) which took place in Toronto, Canada in September 2019.
While they were originally part of the Global Summit, these authors formed a breakaway group with unique characteristics. For one, they are ardent advocates for a more evidence-based chiropractic. Traditionally, chiropractic has been justified using pseudoscientific arguments, propaganda, and a partnership with anti-vaccination and alternative medical views. What is unique about Goertz, Hurwitz, Murphy, and Coulter (the four breakaway authors) is the quality of their previous scholarly work and their stance against chiropractic’s pseudoscience. For example, when the International Chiropractic Association released what was essentially an anti-vaccination propaganda piece, they joined in writing and/or signing of a united statement calling for “an end to pseudoscientific claims on the effect of chiropractic care on immune function.” that was published by Cote et al. (2020) in Chiropractic & Manual Therapies titled “A united statement of the global chiropractic research community against the pseudoscientific claim that chiropractic care boosts immunity.” To simply brush aside the fact that these authors have a track record of standing for the evidence in the public sphere would be dishonest, setting one at odds with individuals attempting to renovate a field that has cozied up to pseudoscience since its inception.
As I wrote in my initial memoir, my childhood was spent with a rather pseudoscientific chiropractic father and grandfather. As such, I remember and continue to read the works they reference to justify their philosophy, especially their ties with the alternative movements. Comparing this personal experience to the work of the Global Summit and Goertz et al. is my way of staying current on the socio-cultural phenomenon and philosophical positions of modern-day chiropractic research and practice. I hope to learn more about Goertz et al. and their unique position as advocates for evidence-based chiropractic. I hope that the reader will follow along to see that evidence hierarchies and what we make of them matter to current practice and policy beyond just allopathic medicine. Suppose it can be shown that EBM, though well-intentioned, is an incomplete philosophical endeavor. In that case, it will be necessary to either discard it or improve it, lest we open up medicine to quackery. One thing I am sure of, medicine is deeply social, political, and philosophical. Numerous groups vie for influence and it is crucial that we properly define who they are by listening to them, not by immediately brushing them to the side. That is why you will find me writing about the potential for an evidence-based chiropractic and what that may mean for EBM and allopathic medicine. I invite my readers to follow me here Judah Kreinbrook or on Twitter: JMedic2JDoc.
- Dollery, CT (1972). “Constructive Attack. Effectiveness and Efficiency. Random Reflections on Health Services (AL Cochrane)”. Book Reviews. British Medical Journal. 56.
- Blunt, C. J. (2020, April 22). Random reflections: Cochrane and the origins of hierarchies. http://cjblunt.com/random-reflections.
- Blunt, C. J. (2013, April 6). The disunity of evidence-based medicine. http://cjblunt.com/the-disunity-of-evidence-based-medicine/.
- Aberle, D.F. (1966) The Peyote Religion Among the Navaho. Chicago: Aldine.
- Perlstadt, H. (2016). The Plague of Athens and the Cult of Asclepius: A Case Study of Collective Behavior and a Social Movement. Sociology and Anthropology, 4(12), 1048–1053. https://doi.org/10.13189/sa.2016.041203
