A comprehensive approach to your medical problems is very helpful. Being aware of all your potential diagnosis and treatment options leads to better decision making. However, while investigating any health topic, you'll quickly notice a dilemma: there are too many options.
Think about supplements; there are 90,000 supplements currently on the US market. Each one claiming to be, not only a treatment, but a “panacea”, a cure to many problems with no side effects.
Why are there so many cures? They can't all work. This is where critical thinking comes in. We need a filter to help sort out the ones more likely to work from the ones less likely to work.
What is critical thinking, and how to apply it to healthcare
Critical thinking is a set of tools that help us correct bad thinking. It’s based on three main principles:
We are ALL prone to bad thinking. In healthcare we want our intervention to work.
A claim is only as good as the evidence that supports it. In healthcare some evidence is better than others.
A healthcare claim based on weak evidence is most likely to be wrong.
Let's reveiw each one of these starting with the first principle…
We are ALL prone to bad thinking
The most important prerequisite of critical thinking is to acknowledge that everyone's thinking, including your own, is flawed. Like any tool, our brains have limitations. They are not as accurate as we think. We are social creatures with complex emotions. Our brains were designed to think quickly for survival - not to solve complex problems. Thinking critically is an unnatural act.
We see patterns that are not there. We engage in confirmation bias, selecting evidence that confirms our claims and ignoring evidence that disconfirms them. And we are easily biased by personal drives and incentives. There are so many cures in healthcare because each player involved is biased to make their product look good.
The academics are incentivized because a cure leads to fame, fortune, and academic advancement. In an analysis of 2,000,000 medical studies, 96% had positive results. There is no incentive to replicate most of these results because no one wins a Nobel prize for showing a treatment does NOT work. When we actually try to replicate these studies, less than 25% can be replicated. This is known as “the replication crisis” in science.
Industry is also incentivized to make their products look better than they are. For many products, like supplements which are completely deregulated, industry can make any claim it wants. For products that are regulated, industry has learned to beat the system. They test their own products, spins the results, and even influence the other players in healthcare by funding academics, doctors, and bombarding patients with marketing and podcasts.
Healthcare practitioners are incentivized to offer cures to their patients. Whether they practice alternative medicine or conventional medicine, whether they are altruistic or avaricious, they need answers and cures, otherwise they're of no use to their patients.
Finally, patients are biased to welcome cures. Pain, suffering, and the fear of death are very strong motivators indeed. It’s understandable that this clouds judgement; even for patients who normally exercise excellent judgement in other aspects of life. Wishful thinking makes them gloss over details and lower their standards for evidence.
Some evidence is better than other evidence
Over the last 40 years we have tested different kinds of evidence against one another to determine how reliable each kind is. The results form the basis of Evidence-based Medicine and established what's called, the "hierarchy of evidence". Some evidence is unreliable, like: anecdotes, laboratory evidence, animal studies, and observational studies. They are a good starting point and may lead to something, but they are prone to errors and needs to be confirmed with better evidence.
The best kind evidence is the randomized placebo controlled trial. It is designed to correct for the problem encountered with the weaker evidence. Unfortunately, randomized trials are limited by their expense, their feasibility, and like any kind of evidence, not immune to fraud.
A healthcare claim based on weak evidence is most likely wrong
How do we know this? It's actually quite simple. We can follow the pharmaceutical industry. They take the best ideas from weak evidence, and as a regulated industry, must put them through very large randomized trials prove they are safe and effective. Question... for every 100 drugs how many will actually pass these trials?
The answer... less than 1%. Take note, that rate is in the best hands. The pharmacetucal industry has the best scientists, with the most resources, and the most money on the line. With respect to Alzheimers disease, they found 140 drug candidates over the last 30 years. None of them worked. They spent $600 billion. What is the likelihood the supplement on TV has found the cure to Alzheimer's? Cures in medicine are few and far between. Every Penicillin lies on a mountain of failures you don't see.
A standardized approach to evaluating a medical claim
Now that you understand the biases in healthcare and the value of different kinds of evidence, we can generate a standardized approach to evaluate any claim. Below is an example:
Establish the burden of proof. Because most claims in medicine are wrong, those who claim to know the cause or cure of a disease need to present their evidence.
Tackle one claim at a time. Some treatments claim to treat many conditions - from cancer to wrinkles. This is distracting.. Tackle one at a time. The one most pertinent to you.
Stick with claims that are measurable. A treatment may claim to 'boosts your energy'. Energy is a subjective feeling and hard to measure. A supplement may claim to "reverse aging", how would you know it is working?
Assess plausibility. Is the treatment congruent with our current understanding of the laws of nature. For example, Reiki therapy and homeopathy are not. Does implausibility preclude the claim is false. No. However, an implausible claim should require stronger evidence. As Carl Sagan said, "Extraordinary claims require extraordinary evidence."
Evaluate ALL the evidence. To avoid confirmation bias.
Rank the evidence. Using the hierarchy of evidence.
Get a second opinion from: regulatory agencies (FDA), professional societies (AMA ACS), and your primary care doctor.
(For a more detailed explanation check out my lecture on YouTube)
Concierge medicine and evaluating claims
The Concierge Medicine model is the optimal platform to employ critical thinking in medicine. Because my practice is small I have ample time to evaluate all of my patient's queries, and even time to teach them how to evaluate claims for themselves.
Over the last 25 years I've evaluated thousands of healthcare claims. Since most evidence is weak and preliminary, it should not be of no surprising that I found most of these claims unlikely to be true. This may leave patients with few options to solve their medical problems with. However, the purpose of evalutating claims is not to make decicsions and close doors. On the contrary, it's a way of empowering you by assigning an objective probability to the claim. What you decide to do with that information is your choice. Every claim is different, every situation is different, every patient is different, and every patient's tolernace for risk is different. Helping you decide which claims you should try and which you shouldn't is another skill of critical thinking in medicine. It's called shared decision making. You can read about it here.
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