Critical appraisal of medical science from outside the walls of the academy is often not well received. The slow-adopting skeptical doctor may be labeled a hater, a nihilist or perhaps even a member of the peanut gallery.
In 2019, Drs Adam Cifu, Vinay Prasad, Andrew Foy and I wrote the Case for Being a Medical Conservative. (It was Andrew’s idea.)
The American Journal of Medicine published our essay, and Stanford economist Russ Roberts discussed it on his EconTalk podcast. A year later, JAMA published a (very) similar viewpoint, but the authors called it “sensible medicine.” Sadly, they didn’t reference our essay.
Here are some of the basic tenets of what it means to be a medical conservative.
Medical Conservatives Laud “True” Progress
A medical conservative is not a nihilist. In our original essay, we cited the amazing progress made in some cancers and AIDS. The rapid development of mRNA vaccines against SARS-CoV-2 is as great an achievement.
Take the Pfizer vaccine paper from the NEJM: the 95% reduction in symptomatic COVID-19 cases is something rarely seen in modern science. The difference in number of infections in the vaccine arm (8) and placebo arm (162) is ≈ 12 standard deviations from no different.
If you do a likelihood ratio of the probability that the data is consistent with the null hypothesis (vaccine doesn’t work) over the probability that the data is consistent with the alternate hypothesis (vaccine does work), the fraction has almost 30 zeros.
The mRNA vaccine data is about as strong as medical evidence can get. In Israel, rapid vaccination has nearly stopped COVID-19 deaths.
The problem with the vast majority of medical evidence is that many developments promoted as major advances offer at best marginal benefits.
Andrew Foy and I wrote about the relationship between costs and benefits of medical interventions. Sadly, much of what we do in cardiology resides on the flat part of the curve—high costs and little benefit. Vinay Prasad wrote Malignant, a book on how bad policy and bad evidence harm people.
Medical conservatives worry that money spent on low-value care reduces the ability to provide high-value care to the less fortunate.
The challenge in changing policy, of course, is that the entire healthcare industry profits from flat-of-the-curve practices.
Due to Uncertainty, Medical Conservatives Support Decision Quality
A recent review of 26 cardiology guidelines and more than 2600 specific recommendations found that less than a quarter of codified practices were backed by strong evidence. Pause there.
One particularly bothersome area of uncertainty is the difference between helping a population vs helping an individual. The statin example comes up again. Here is what we wrote in the Am J Med:
While acknowledging that widespread uptake of statin drugs for primary prevention might prevent many nonfatal cardiac events in a population, the conservative clinician deals with one patient at a time and is careful to communicate the absolute benefits/harms of the drug for that individual.
The question we ask is simple: Would an unbiased patient, who had perfect knowledge of an intervention’s tradeoffs, voluntarily choose to adopt it, and taking into account differing patient resources, pay for it?
One of my research areas is in the use of decision aids to help patients make more informed decisions. A patient may ask: “do I need that medicine,” and my response is that need is the wrong verb. Let’s look at the tradeoffs, and how you feel about them.
Decision aids have been shown to improve decision quality, but their adoption has been slow—perhaps because they reduce the asymmetry of power in the doctor-patient relationship.
Medical conservatives believe that more transparency about the smallness of the effect sizes of many of our interventions would lessen low-value care.
Medical Conservatives and the Commercialization of Medicine
When money is at stake, hype and spin usually follow.
A paper I co-authored found that spin—language that distracts from a nonsignificant primary endpoint—is common in cardiology. Spin deceives the reader, helps propagate flat-of-the-curve practices, and has pernicious effects on public trust.
I discussed an egregious case of spin in my Expertise is Over-Rated newsletter. Spin is terrible and should be mercilessly called out.
But many mistake the medical conservatives’ concern about commercialization of medicine as opposition to free enterprise, capitalism and the accumulation of wealth. This is not true.
A great example: in patients with heart failure, chronic kidney disease and diabetes, industry-physician collaboration has led to a whole new class of drugs that help slow progression of disease and reduce cardiac complications.
The entrepreneurs and scientists who made these gains possible should be rewarded. Doing so will incentivize others to make progress. Because of capitalism, it’s never been a better time to be sick.
What medical conservatives oppose, however, is the accumulation of private wealth when it occurs under the pretext of "science", without meaningful improvement in patient outcomes.
And this is why critical appraisal of medical evidence is so critical.
Medical Conservatives Rely on *Neutral* Critical Appraisal
The peer-review model of medical science holds that content experts do most of the critical appraisal. This can be a problem because content experts come with entrenched biases—both financial and intellectual.
Intellectual (or content-expert) bias reminds me of David Foster Wallace’s famous This is Water commencement speech:
There are these two young fish swimming along and they happen to meet an older fish swimming the other way, who nods at them and says “Morning, boys. How’s the water?” And the two young fish swim on for a bit, and then eventually one of them looks over at the other and goes “What the hell is water?”
Imagine a person whose career is dedicated to a certain therapy or theory. This person naturally becomes an enthusiast. But being so close may prevent seeing the flaws or biases in the evidence. Yet these scientists often hold serious power in the prevailing dogma. (Think journal editors.)
Medicine is replete with examples of doctors acting like DFW’s fish.
Here is one of my favorite examples: when I was a younger doctor, ICU doctors placed catheters in the heart and lungs to measure pressures. Enthusiasts of these bright yellow catheters, named after two legends, Drs. Swan and Ganz, felt that the data helped manage complex patients. I spent many hours learning how to interpret the data.
But then, thirty (three zero) years later, trials came out showing the catheters did not improve outcomes.
The medical conservative, therefore, is like a neutral Martian—an outsider who notices that a costly and invasive catheter should come with evidence that it delivers benefit.
The neutral observer might be akin to “someone who stands athwart history, yelling Stop, at a time when no one is inclined to do so, or have much patience with those who urge it.”
Imagine the lives saved if this practice had been tested before its adoption.
The medically conservative approach to medicine holds that the onus is on proponents to show neutral judges that new stuff actually works.
This requires proper testing in rigorous clinical trials.
In future writings I will show you what a proper trial looks like and how to interpret its data without being bamboozled.
Great write up and lessons to ponder over by freshly minted cardiologists from various medical schools all over the world. Brilliant article.
Hey Dr. John - Great post. Where do you stand on getting the vaccine if you have already contracted Covid?