Veterinary Quackery–Circa 1921

I recently ran across an edition of the Journal of the American Veterinary Medical Association from 1921 which contained a few tidbits that I found interesting concerning the distinction between scientifically trained veterinarians and their “empirical” competitors. Such documents are always entertaining for the dramatic difference in tone and cultural perspective between then and now, and for the insight into how things were different and, sometimes, how they were the same. The entire issue is available on Google books.

Merillat LA. Some notes on the comparative study of veterinary medicine in France and the United States. Journal of the American Veterinary Medical Association 1921;58(11):64-73.

The author apparently spent two years working with French veterinarians during the First World War, and he has nothing but praise for the high standards of scientific training and expertise among them, which he seems to consider better than the contemporary standards in the U.S. The passage of particular interest here is the following.

There are no veterinary laws in France as we know them in our several States. Anyone may practice, but the nongraduate is under such restrictions as to the particular disease he may treat and the drugs he may prescribe that the activities of the empirical practitioner are somewhat curbed. I say “somewhat” advisedly, because quackery is not unknown in France. In my travels in the rural districts I made a special effort to gather some information in this respect, and found that almost every community supported its handy horse and cattle doctor. The fact that all of the regular veterinarians were at the front may have intensified the situation and may have made it appear more grave than under normal peace-time conditions. I fear, however, from information thus obtained and that gathered by living almost a year in the home of a leading veterinarian of Paris, that the situation as regards empiricism is far from satisfactory to the practicing veterinarian, and I am also assured that the condition in Holland, Belgium, Germany and Italy is no better. In these countries empiricism and the patent-medicine industry thrive uncurbed. Judging from advertisements in the lay press and periodicals, it is legal to sell nostrums regardless of contents or of the effects claimed for them. Thus the veterinary practitioner, after having made this splendid preparation to practice, is little protected against cheap opposition. Then it appears that medical enormities and superstitions are practiced more among ‘the European laymen than among the more intelligent American.

The one feature in which the French veterinarian differs most from us in this respect is the way he has been able to dignify his calling and separate himself from the empiric. Here we are still classed with the lowest type of charlatan, while in France everyone knows that the veterinarian and the quack belong to two entirely different categories of individuals. Here we fight the quack to rid ourselves of an undesirable companion, while in France no complaint is entered so long as the quack does not overstep his legal domain. The French practitioner looks on cheerfully as if rather satisfied to be rid of the uncanny and gruesome jobs he might be called upon to do if the quack were not in existence. This I think explains the status of the quack situation in Continental Europe.

First, of course, we note the natural and relaxed use of the term “quack,” which today would never find its way into any official publication of the AVMA. While the haughty and paternalistic attitude of the medical mainstream in the early 20th century is deservedly a thing of the past, we have perhaps become too democratic in banning any sort of pejorative characterization of useless or nonsensical treatments. I suspect the successful anti-trust litigation pursued by chiropractors against the American medical Association in 1976 may explain this to a significant degree. In any case, “quack” is now a much rarer term, for better or worse.

We also see the beginnings of the desire for American veterinarians to be seen as scientists and professionals, which of course required emulating the kind of scientific training and methods the author so admires in his French colleagues. ” Here we are still classed with the lowest type of charlatan, while in France everyone knows that the veterinarian and the quack belong to two entirely different categories of individuals.” Certainly today, veterinarians are pretty respected and trusted as a profession, but one of the dangers of not being vigilant in maintaining a high scientific standard for our clinical practices is that of becoming indistinguishable in the public eye from “charlatans.” Embracing unproven methods and a anecdote-based epistemology is a sure way to dilute the credibility we have earned as a profession through our dedication to progress and sound science.

There’s a bit of unselfconscious ethnocentrism in the statement ” medical enormities and superstitions are practiced more among the European laymen than among the more intelligent American” that we can afford to think of as quaint since it is so obviously not an attitude that would be acceptable today.

And finally, there’s the discussion of the relationship between mainstream, scientific veterinary medicine and the alternatives, unscientific folk practices, patent medicines, and so on. On one hand, there is an obvious sense of resentment at the idea of veterinarians undergoing rigorous scientific training only to be in competition for patients with untrained lay people who are allowed to sell whatever nostrums they like regardless of their usefulness. And in contrast is the picture painted of an almost idyllic division of labor between the scientific practitioner and the quack. The situation in France is described as one in which the laws allow unscientific, or “empirical” veterinary practices so long as they are confined to domains not reserved for “real” veterinarians. What sort of restrictions are in place is not stated, but one can imagine it might be a system analogous to the veterinary practice acts of the states, in which the “practice of veterinary medicine” is limited to veterinarians, and debates then ensue as to what this encompasses.

In California, for example, performing chiropractic on animals is considered veterinary medicine, so it is required to be done by licensed chiropractors but only under the “direct supervision” of licensed veterinarians. This really only amounts to an exam by the vet within the last year and a referral for chiropractic, but occasionally I am able to catch a case in which a patient comes to our hospital for chiropractic only but I find a serious disease that requires real treatment during my “pro forma” exam of the patient, so I am able to steer them towards real therapy.

Today, the position of the AVMA and other professional veterinary lobbies seems to be that they don’t care what kind of treatment is offered or whether it has any scientific legitimacy so long as only veterinarians are allowed to offer it. This seems a total abdication of any responsibility for protecting the public from quackery and a bit of crass protectionism to me. Granted, there are political considerations since a fair number of veterinarians believe in CAM treatments, so the kind of direct condemnation of them found in this old article wouldn’t be politically possible these days. Still, the article clearly demonstrates that much the same sort of conflict that exists today, between legitimate medical practices based in science and “empirical” practices based in folklore or personal intuition, existed nearly a century ago. The more things change, the more they stay the same.

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“Holistic Medicine”–It means whatever we say it means

The American Holistic Veterinary Medical Association (AHVMA) has a statement on their web site explaining what “holistic” medicine is. I was interested in this because it’s a slippery word, seemingly simple on the surface but hard to pin down. Superficially, the word comes from the Greek root for “whole” and simply means a perspective that looks at phenomena (organisms, systems, etc) as wholes, rather than analyzing them at the level of component parts. This is simply one of many levels on which phenomena can, and should be examined.

The problem is that this perspective is difficult to distinguish from mysticism and the notion that natural phenomena are irreducibly complex and nothing meaningful can be learned by examining their components. Reductionism and holism should be complementary, but philosophically and politically they are more often seen as incompatible. Thus “holistic” becomes less a term describing an epistemological perspective and more a philosophical or political shibboleth distinguishing those who disdain the methods and explanatory power of science and prefer mystical, vitalist explanations to scientific ones from those of us who see utility and real truth in the explanations science gives at the component as well as the system level. Let’s go through the AHVMA statement and see if we can find some clarity.

 First, it recommends looking at “all aspects of the animal’s life.” Of course, that isn’t what they really mean since that is a practical impossibility. Could the patient’s cancer have been caused by once walking across a linoleum floor? Is she diabetic because the light shining through the bedroom window is filtered by oak leaves not maple? If we truly believe everything is relevant then we are helpless to make any useful conclusions at all. What they really mean is just that they want to know about things they consider relevant and which scientific medicine often does not. The trick, then, is to demonstrate that these things truly are relevant, which often fails to happen.

Next the statement recommends “employing all of the practitioner’s senses” when evaluating the patient. I’d be surprised if holistic veterinarians make a lot more use of taste than conventional vets, so generally the idea of using all ones senses in examining a patient doesn’t distinguish scientific from holistic medicine since both use a multisensory examination. Of course, this may be referring to “senses” which science does not acknowledge as being real, such as the psychic awareness of thoughts and emotions or “bioenergetic field” techniques that have been discussed in some of the organization’s continuing education literature and its journal. In that case, it would be true that conventional vets don’t use these “senses.”

Now we get to the heart of what “holistic” is truly used to signify, when the statement recommends “the combination of conventional and alternative (or complementary) modalities of treatment.” There is nothing intrinsic in the concept of holism that requires accepting or using CAM therapies. As I’ve pointed out before, CAM therapies often have theoretical foundations that are completely incompatible with each other, though they tend to be united by vitalist tendencies. Chiropractic is not “holistic” at all according to the root sense. It focuses exclusively on supposed misalignment of the spine as the source of all disease and the object of all treatments. Homeopathy, on the other hand, couldn’t care less about the spine when diagnosing or treating an illness but does treat all diseases with whatever substances are believed to mimic the symptoms of the patient when given to healthy people. CAM therapies are not necessarily any less reductionist than scientific medicine, so identifying their use as a component of the holistic veterinary medical approach betrays the ultimately political and marketing nature of the term. It is a warm and fuzzy umbrella under which to gather methods not usually validated by science. CAM therapies are often very narrowly focused on “one true cause” of all disease or the “one true therapy” for all ailments, they just pick a cause or therapy that is unproven or disproven by science.

The statement claims that a vet who follows the holistic approach “wants to find out all about its behaviors, distant medical and dietary history, and its environment including diet, emotional stresses, and other factors.” These sound like the same sort of historical variables any veterinarian considers in gathering data about a patient’s health and disease. The specific meaning attributed to each factor is likely different between science-based and “holistic” vets, but it is a bit of dishonest marketing to suggest conventional doctors are reductionist to the point of ignoring such obviously relevant factors as diet and prior medical history. As I’ve said before, ” I’ve never actually met a veterinarian who considers the patient irrelevant to the health of the knee or the gallbladder or the white blood cell, but CAVM practitioners like to suggest that such myopia is the only alternative to embracing vitalism and faith-based medicine.”

Next we have a very broad-brush paint job illustrating how really nice holistic vets are:  

“Holistic medicine, by its very nature, is humane to the core. The wholeness of its scope will set up a lifestyle for the animal that is most appropriate. The techniques used in holistic medicine are gentle, minimally invasive, and incorporate patient well-being and stress reduction. Holistic thinking is centered on love, empathy and respect.”

All of these vague, pleasant characterizations apply equally well to veterinarians who practice science-based medicine. I might quibble with what is really meant by “love” and “empathy,” since I think these terms are often a cover for claims that alternative practitioners are psychically in touch with the spirits or souls of their patients, a claim I think is more about religion than medicine. But the fact that conventional veterinarians are interested in facts, evidence, and truth does not, as CAM vets like to suggest, imply that somehow they aren’t human beings capable of treating their patients and clients with as much kindness and compassion as anyone else. I would argue evidence-based medicine is a pre-requisite for truly compassionate care since without it we are likely to offer our patents ineffective and even harmful therapies that don’t really help them.

Now comes a summary of the holistic medicine methodology:

“The holistic practitioner is interested in genetics, nutrition, family relationships, hygiene, and stress factors. Many patients present in a state of “disease.” At this point the holistic challenge lies in the question “why?” By a series of analytic observations and appropriate testing the goal becomes finding the true root source of the pathology. A simple-appearing symptom may have several layers of causation. Only when the true cause of the ailment has been found is there the possibility for a lasting recovery.

It is at this point that the most efficacious, least invasive, least expensive, and least harmful path to cure is selected. “

This sounds like a fair description of clinical medicine in general. Nothing here distinguishes a holistic approach from a conventional approach. The implication, of course, is that this is not the method a conventional veterinarian follows because presumably we’re so busy focusing with tunnel vision on superficial symptoms and reaching for toxic drugs that we aren’t looking deeply enough. Fortunately for our patients, this is just a vapid cliché.

Finally, we have this qualifier:

” In many acute situations, treatment may involve aspects of surgery and drug therapy from conventional western technology, along with alternative techniques to provide a complementary whole. This form of treatment has great value for severe trauma and certain infections. It often outperforms other methodologies. It is also at this time that other treatment plans such as those listed below are brought into use. Once the symptoms have been treated, the task is not complete until the underlying disease patterns have been redirected. The patient, as well as the client, will be guided to a new level of health. “

I have taken the liberty of translating this for those not intimately familiar with CAM-speak:

When we have a definable disease or an urgent medical problem, we reach for scientific medicine because it works better. However, when we have vague or hard to define symptoms or we’re just trying to convince the owner that ongoing health can only be achieved and maintained by constant subtle adjustments of the unmeasurable essence of life, then we reach for alternative methods since they and their effects are also vague and hard to define.

 

There is no question that the concept of holism in its original form has some value. Things can be understood about complex systems at the whole system level that may be missed when looking at their component parts. And some systems may exhibit behavior that is intrinsically not predictable at the component level even though they are fundamentally deterministic (see chaos theory) while other systems may be fundamentally indeterministic. However, none of this legitimate epistemological theory has anything to do with vitalist mysticism or the embracing of unproven or even disproven medical approaches. Looking at the whole patient in its real life context is a valuable element to understanding health and disease. Using any and all therapies that sound good to us regardless of whether or not they have real value is a mistake. Unfortunately, the popular use of “holistic” to market CAM therapies confounds these unrelated approaches.

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Spinmaster Messonier at it again

I recently discussed, and corrected, some comments Dr. Shawn Messonier made on his blog concerning Alison Averis’ post here illustrating how personal experience can be unreliable in evaluating whether a medical treatment works or not. Dr. Messonier has responded to some of the comments I made in that post, as usual trying to warp them to fit his pro-CAM “talking points.” He begins by dredging up that vacuous marketing label of “healthcare choice” which I’ve discussed before.

While most doctors and healthcare providers are open to natural care and support your choice and the type of medicine you desire, sadly there are still many that will come up with any argument and do anything to prove to you that your choice is wrong.

This argument presumes that giving people more therapies to chose from, even if they are useless or even harmful, is somehow a good thing. It also suggests that informing people about what reliable, scientific evidence is and how they can use it to help them make good choices for their pets is somehow limiting the freedom or autonomy of pet owners.

I offer choices to my clients every day, and I expect them to be full partners in caring for their pets. I do not offer them the option of psychic diagnosis or therapy, animal sacrifice to propitiate the gods of health, or homeopathy because those would be false choices of no real value. And if there is a therapy that I believe might be beneficial but about which there is significant uncertainty, I give them that information so their choices will be informed. Adding meaningless buzzwords like “natural” to what one does, regardless of whether there is reliable evidence to support that it is safe or effective, is purely a marketing strategy, not a means to give greater autonomy or choice to pet owners.

Dr. M then goes on to quote my recent post and respond to specific bits and pieces.

1.“Doctors rely on their personal experiences, intuition and, anecdotes as evidence to justify implausible or simply “made up” theories and practices.”

This is partly true, but it’s also true for doctors who practice conventional medicine as well. In the good old days before strictly controlled, well-funded (usually by the drug companies seeking approval for their latest drug) studies, ALL doctors learned and shared knowledge based upon their personal experiences with various medications (both natural and conventional.) There is nothing wrong with learning from experience and sharing these experiences. Yes, we all would love to have well researched studies “proving” what we already know to be factually correct. However, the company funding the study determines which studies are ultimately published. While most companies are ethical, there have been some well-publicized incidents of companies ignoring negative studies and only publishing positive studies showing benefits for their medications.

*Evidence is evidence. Either a treatment works or it doesn’t. While skeptics selectively ignore evidence showing the effectiveness of natural therapies, they never seem to ignore evidence showing natural therapies don’t work.

Several problems here. First, Dr. M is unfortunately correct that many doctors practicing primarily conventional medicine rely unduly on anecdote and personal experience. This does not, of course, mean it is the right approach, and I hope that the practice of science and evidence-based medicine will come to be the predominant approach to medical knowledge among all veterinarians. It is certainly more likely to take hold among those who already practice medical approaches that are based on sound scientific reasoning and evidence than among those who, like Dr. M, confidently assert the value of therapies that are unscientific in their underlying premises or without good supporting evidence. I certainly do not claim perfection in conventional medicine, I simply advocate for all of us as veterinarians and pet owners to recognize our limitations and attempt to do better by turning to the most reliable evidence available concerning the therapies we use.

The underlying problem with the CAM approach to knowledge is explicit in this statement. Dr. M pays lip service to scientific evidence, but he clearly views it as icing on the cake, “‘proving’ what we already know to be factually correct.” The arrogance of this kind of self-certainty is breathtaking. Science and the knowledge it generates is not merely a way of better promoting and marketing what we already believe. It is a way of finding the truth despite our own limitations and cognitive biases. There can be no learning or improvement without the recognition that our knowledge is incomplete and flawed, and yet Dr. M clearly does not believe this. To him, science is simply another tool in the promotion of his beliefs, not a way to find out what is true and what isn’t.

As far as the issue of funding bias and publication bias, there is no question these are real problems. They do not, however, invalidate the whole enterprise of scientific research, as the good doctor suggests. There is plenty of research evidence available, both from industry-funded research and from other sources (academia, government, private clinical practices, etc), and acknowledging that there are weakness in some of this research is not license to ignore it and simply do what we feel like doing.

“Evidence is evidence” is nonsense. There are levels of evidence ranging from the least reliable (personal opinion and experience) to the most reliable (multiple consistent well-designed and conducted clinical trials). The problem many CAM practitioners have is reading the pyramid of evidence upside down:

Undoubtedly, we all suffer from confirmation bias, so it is true we attend to evidence that supports our beliefs more than evidence that disconfirms them. This is a major reason why scientific evidence is more reliable than anecdote and personal experience, so raising the issue simply undermines Dr. M’s own approach. If he has specific evidence for particular therapies he thinks I am ignoring, his is of course always welcome to provide it for consideration.

2.“I would be very interested in how much “objective” measuring of outcomes doctors using natural therapies actually do. They often seem to imagine they can “eliminate” subjective owner assessments in practice, but I find this hard to believe.”

Let me quickly answer this objection by sharing with you two recent cases. One involves a dog with elevated kidney enzymes that did not respond to treatment by his prior conventional veterinarian. The other case involves a cat with elevated liver enzymes and also did not respond to treatment by her conventional veterinarian. After using several natural therapies, follow-up blood tests showed that the kidney and liver enzymes returned to normal.

There is nothing subjective about this. The laboratory, which did not know what kind of therapy I used on these patients, reported the results objectively.

Even in trying to show how objective his medical practice is, Dr. M cannot help but rely on anecdotes to prove his point. Of course, the flaw here is glaringly obvious. He assumes that improvements in the clinical laboratory values measured was due to his therapy. This is the post hoc ergo propter hoc fallacy, and it ignores the fact that medical problems can improve for all sorts of reasons other than the ones we assume. Some possibilities include:

1. Self-Limiting Disease Many diseases are self-limiting. If the condition is not chronic or fatal, the body’s own recuperative processes usually restore the sufferer to health. Thus, to demonstrate that a therapy is effective, its proponents must show that the number of patients improved exceeds the number expected to recover without any treatment at all. Without detailed records of successes and failures for a large enough number of patients with the same complaint, someone cannot legitimately claim to have exceeded the norms for unaided recovery.

2. Waxing and Waning Chronic Disease
(also known as Regression to the Mean) Such conditions as arthritis, allergies, and gastrointestinal problems normally have “ups and downs.” Naturally, clients tend to seek therapy during the period or greatest clinical symptoms. In this way, a treatment will have repeated opportunities to coincide with upturns that would have happened anyway.


3. Multiple Concurrent Therapies If improvement occurs after a pet has had several interventions, and probably other unremarked changes in the owner’s treatment of the sick pet, one or another of the changes often gets a disproportionate share of the credit or blame. Frequently, the latest in a series of interventions or the newest thing tried is credited with improvement even though many things were done.

The overall tone of Dr. M’s response is that I am somehow on a crusade against “natural” medicine. That cannot be true for the simple reason that “natural medicine” is a meaningless term filled with assumptions and the naturalistic fallacy. I am actually on the same crusade as Dr. M. I am dedicated to giving my patients the best, most effective care and the highest quality of life possible, and to protecting them from things that are useless or harmful. The difference is not one of intention, but one of philosophy. I believe there is such a thing as truth and that the best way to  care for our pets is to know what is true and what is false about the therapies we offer. I believe that we often don’t know what we think we know, and that our confidence in our own intuition and judgments is often excessive and unjustified. I believe that science is the most powerful tool we’ve ever invented for separating truth from mythology, and that with it we have done, and will continue to do, better in medicine that we did in all the thousands of ears we relied exclusively on storytelling, respect for tradition and authority, and random trial and error to decide what works and what doesn’t.

If this blog is controversial or challenging, it is because when I find the evidence doesn’t support the claims people make about veterinary medicine I have the temerity to say so. I try to do so in a civil way, and I try to focus on the problems of reasoning and evidence rather than personality, though I won’t claim I never give in to irritation at the persistence of mischaracterization and misinformation in some people’s arguments. But helping pet owners to take better care of their companions isn’t accomplished by ignoring the evidence or by letting unsupported claims or misleading arguments stand, and I make no apologies for trying to help people filter the information available to them and separate the strong, reliable claims from the weak or thoroughly bogus ones. I’m happy to discuss what the evidence is and what it means with anyone, but Dr. M prefers simply to insinuate and allege motives, to throw around meaningless marketing terms, and to talk about anything but the specific evidence for or against the therapies he advocates.

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Give a Dog a Bone (Not!)–FDA warns of dangers of feeding bones to dogs

The Food and Drug Administration issue a warning about feeding bones to dogs recently. Just like feeding milk to cats (which also isn’t a very good idea), giving bones to dogs is a cultural cliché that we learn about as children. Bones are often the symbol for all things canine. Unfortunately, the idea that they are a fun and healthy part of the domestic dog’s diet is a myth. Eating bones can result in all sorts of medical problems, some minor and some serious. The FDA warning lists some of the more important:

  1. Broken teeth. This may call for expensive veterinary dentistry.
  2. Mouth or tongue injuries. These can be very bloody and messy and may require a trip to see your veterinarian.
  3. Bone gets looped around your dog’s lower jaw. This can be frightening or painful for your dog and potentially costly to you, as it usually means a trip to see your veterinarian.
  4. Bone gets stuck in esophagus, the tube that food travels through to reach the stomach. Your dog may gag, trying to bring the bone back up, and will need to see your veterinarian.
  5. Bone gets stuck in windpipe. This may happen if your dog accidentally inhales a small enough piece of bone. This is an emergency because your dog will have trouble breathing. Get your pet to your veterinarian immediately!
  6. Bone gets stuck in stomach. It went down just fine, but the bone may be too big to pass out of the stomach and into the intestines. Depending on the bone’s size, your dog may need surgery or upper gastrointestinal endoscopy, a procedure in which your veterinarian uses a long tube with a built-in camera and grabbing tools to try to remove the stuck bone from the stomach.
  7. Bone gets stuck in intestines and causes a blockage. It may be time for surgery.
  8. Constipation due to bone fragments. Your dog may have a hard time passing the bone fragments because they’re very sharp and they scrape the inside of the large intestine or rectum as they move along. This causes severe pain and may require a visit to your veterinarian.
  9. Severe bleeding from the rectum. This is very messy and can be dangerous. It’s time for a trip to see your veterinarian.
  10. Peritonitis. This nasty, difficult-to-treat bacterial infection of the abdomen is caused when bone fragments poke holes in your dog’s stomach or intestines. Your dog needs an emergency visit to your veterinarian because peritonitis can kill your dog.

Now, I can already hear the BARF and other raw diet and bone folks rattling off anecdotes about all the dogs they have fed bones who lived perfectly happy, healthy lives. That this proves nothing shouldn’t need saying, but of course it does. Plenty of people who smoke never get lung cancer, and some people who do get it never smoked. Does that mean smoking doesn’t increase your risk of getting cancer? Of course not. 90% of lung cancers are associated with smoking cigarettes, so the fact that lots of people get lucky doesn’t mean it’s a risk worth taking.

The same is true for dogs eating bones. Sure, many of them will get away with it. But why take the risk? As I’ve explained before, the idea that domestic dogs are functionally the same as wolves from the point of view of nutrition and should eat whatever wild wolves eat is a fairy tale (see HERE and HERE). There is no evidence that bones are a necessary part of a healthy diet for dogs, and in fact plenty of evidence they are not. Even true wild canine predators, such as wolves, live longer and are healthier when fed commercial diets in captivity. Sure, chewing bones can be a source of pleasure for dogs, but there are plenty of other materials safer for recreational chewing, and given the risks of feeding bones the potential benefits simply aren’t enough to justify the practice.

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Does science affect people’s beliefs? For good or ill?

The fundamental belief underlying this blog is that the truth matters, and that science is the best hope we have of approaching a true understanding of health and disease. I make an effort to investigate and understand the scientific evidence behind veterinary medical approaches and then communicate those findings to my clients and the public because I believe that this is the best way to make the right healthcare decisions for our pets and to avoid the harm and waste of  time, effort, and resources involved in utilizing approaches that don’t work. While I am a realist, and I understand that no amount of objective evidence can change the beliefs of someone with a deep faith in a particular approach or a compelling personal experience that is contrary to the rational, scientific conclusions about it, I still hope that information will truly be power for veterinarians and pet owners, and that we can learn to compensate for our biases and cognitive blind spots and make better, informed decisions.

I do, however, have my doubts. Most polls show that Americans trust scientists more than politicians, but really what does that prove? I trust chiropractors more than, say, the government of Iran, but that doesn’t mean my faith in chiropractors is all that deep. And while polls show most Americans believe science has made life better, most Americans also can’t distinguish between legitimate science and pseudoscience. Purveyors of bogus medical therapies can take advantage of the public’s trust in science easily by simply borrowing or manufacturing jargon than gives the impression of scientific credentials regardless of the real evidence for or against their snake oils. The media can easily manufacture “scientific controversies,” such as those between evolution and intelligent design or between proponents and opponents of the concept of anthropogenic global warming, simply by present on an equal footing two “experts” with differing opinions, regardless of the underlying difference in plausibility or evidence behind these opinions.  So while people trust science to some extent, this is a poor safeguard against the unscientific.

And as a culture, we are deeply faith driven. The overwhelming majority of Americans believe in God, and a solid majority believe God and other spiritual powers are active in daily life, affecting health and disease among other things (for example). So the habit of believing in what cannot be scientifically evaluated is natural to many of us. This makes it difficult to convince people that the scientific evidence against a particular medical therapy should outweigh the personal convictions or testimonials of believers in it, which are generally viewed as at least as good, perhaps better a form of evidence than that provided by science.

A friend recently passed along a social psychology study which, while not definitive by any stretch, does suggest that the picture is even bleaker than this, and that the conclusions of scientists may actually influence people to believe even more strongly in something science demonstrates is not true. The study is called Social influences on paranormal belief: Popular versus scientific support (Curr Res in Soc Psych 2009;15(3)).

Briefly, the investigators gave subjects (the usual undergraduate volunteers) some information about the popular belief and scientific consensus concerning ESP according to four conditions:

Condition 1: Participants read that 25% of the American public believes in ESP and that the scientific community rejects the possibility of ESP.

Condition 2: Participants read that over 90% of the American public believes in ESP and that the scientific community rejects the possibility of ESP.

Condition 3: Participants read that 25% of the American public believes in ESP and that the scientific community is becoming more open to the possibility of ESP.

Conditions 4: Participants read that 90% of the American public believes in ESP and that the scientific community becoming more open to the possibility of ESP.

The subjects then watched a video of a person supposedly demonstrating ESP by guessing the suit of playing cards they could not see. In the video, the guesser is actually informed of the suit and so does much better than one would expect by chance, as someone with ESP would be expected to do. The subjects then completed a questionnaire evaluating their belief in ESP and whether the video was a demonstration of ESP powers.

The mean belief scores were as follows:

Condition 1 (25% of public believes; science rejects): 4.58 (SD = 1.92)

Condition 2 (90% of public believes; science rejects): 4.50 (SD = 1.60)

Condition 3 (25% of public believes; science accepts): 3.58 (SD = 1.84)

 Condition 4 (90% of public believes; science accepts): 4.80 (SD = 1.70)

Analysis of these results showed a significant effect of public belief, with subjects being more likely to believe in ESP if told that most people do. Overall, the scientific community opinion on ESP did not affect the subjects’ level of belief, a depressing hint that science doesn’t have as much influence on the acceptance or rejection of an idea as the popularity of the idea does. However, there was a statistically significant effect of scientific consensus on subject’s belief when ESP was described as not commonly accepted. In this condition, people were more likely to accept ESP as real if scientists rejected it, and more likely to reject ESP if scientists accepted it as possible.

These are not particularly strong findings easily applicable to popular tendencies towards accepting or rejecting the scientific view on implausible propositions, and I don’t mean to make too much of them. However, my personal biases are affected by my own experiences, as everyone’s biases are. I am confronted with depressing regularity by the attitude that what everyone believes cannot be wrong regardless of the soundness of the scientific evidence against it. Personal experience and faith seem in most of us to be far stronger influences on belief than scientific evidence, and even the hint that scientific rejection of an idea may be seen as a reason to believe in that idea worries me.

CAM proponents frequently dismiss scientific evidence with ad hominem reasoning, claiming that the ideological biases or financial interests of those promoting science-based medicine make their conclusions untrustworthy. It is almost automatic for those with unconventional beliefs to assume any evidence provided by commercial researchers (such as those in the pharmaceutical or pet food industries) is worthless at best, if not intentionally deceptive. Could we actually get to the point where the same suspicion was widely applied to science in general, and where scientists were assumed to have ideological or more venal biases that invalidated their conclusions on any idea that claimed itself to be outside the purview of science and more properly in the realm of faith and personal experience? Am I wasting my time trying to convince people that intuitive and traditional ways of knowing the truth about health and disease are inferior to scientific ways? Am I actually promoting the very therapies I criticize because mistrust of science and scientists may incline people to decide in favor of those propositions science argues against?

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Primal Defense-An example of why I am suspicious of probiotics.

For those who have read what I have previously written about probiotics, you’ll know that I am cautiously optimistic about their potential usefulness as a medical therapy, despite the tendency towards overstating the results of the limited clinical trials so far done in veterinary species. The theoretical principle, that administering living organisms orally can have beneficial effects on the GI tract and, potentially, systemically, is certainly reasonable. And there is clinical evidence supporting benefit in humans for some causes of diarrhea and other GI tract disease. The literature concerning veterinary use is very limited and preliminary, with both possible risks and benefits reported but no clear, indisputable evidence for clinical benefit. Still, I certainly think additional research is warranted, and I do sometimes use some probiotic products in my own patients for antibiotic-associated diarrhea.

However, I have a number of concerns about probiotics. Little is known and less understood about the composition and function of the normal GI flora, and what role, if any, organisms not normally found in the gut can have when given therapeutically is unclear. Independent testing of many probiotic  products has also identified serious quality control problems, so it is currently impossible to trust that what you think you are getting is really in many of the commercial probiotics. However, my biggest concern about probiotics is that their widespread acceptance and use goes well beyond what is justified by the available evidence, and this can easily lead to direct harm and even more easily to the kind of indirect harm that comes from substituting unproven remedies for well-demonstrated ones. Exaggerated claims and unscientific, deceptive marketing practices are common in the promotion of such products, and this raises the chances of their doing more harm than good.  The assumption of safety and efficacy that is often made about CAM products has certainly proven, in the case of some such products, to be unfounded, with real harm resulting.

One of the most egregious examples of this is a product which I recently looked into after hearing a number of my clients talking about using it in their pets. Primal Defense is marketed by Garden of Life, and the marketing materials are a laundry list of exaggerated and unsupported claims. Some examples:

“Healthy people usually have a ratio of approximately 85% good to 15% potentially harmful organisms in the intestinal tract. In some cases, even those who appear to be well might have an unfavorable ratio as a result of daily exposure to environmental toxins and a modern lifestyle. “

Here we have the usual vague “toxin” gambit, suggesting that normal life is full of poisons that we need their product to protect us from.

” Large scale use of pesticides, herbicides and other chemicals has changed the bacterial balance of the soil. In order to obtain the benefits we historically acquired from consuming foods cultivated in healthy soil, Garden of Life developed a Homeostatic Soil Organism Probiotic Blend utilizing 12 species of beneficial microorganisms.” 

The idea that modern agricultural practices can affect soil ecology is pretty obvious. The suggestion that this somehow creates deficiencies in nutrients or human/pet gut ecologies that we need this product to correct is totally manufactured and unsubstantiated in any way.

The very use of the term “Homeostatic” is a bit of pseudoscience marketing, since this term has no recognized meaning with regard to probiotics and was apparently made up just for the purpose of making this product sound “sciency.”

The story, however, gets a lot scarier. The marketing of this product involves a great deal of outright lying and deception. The founder of Garden of Life, Jordan Rubin, was fined by the Federal Trade Commission (FTC) for false advertising in connection with Primal Defense and other product in 2006. This including fabricating claims about clinical research studies to support his product claims. He was also ordered by the Food and Drug Administration (FDA) to desist from making false and unsubstantiated health claims in 2004. Mr. Rubin has also claimed to have several academic credentials, including a NMD (naturopathic medical doctor) and PhD. Both degrees, and other credentials he has claimed, come from unaccredited correspondence schools, one of which was actually ordered to close by the state of Hawaii in 2003 for fraudulent practices.

Marketers of Primal Defense frequently state that there is clinical evidence to support their claims for the product. However, no real clinical trials seem to have been published in any recognized scientific journals. For example, claims are made on a number of websites regarding a clinical trial of Primal Defense supposedly published in the journal Progress in Nutrition (Goldberg, P.A. “Primal Defense Homeostatic Soil Organisms As Applied To Medically Unresponsive Chronic Disease Conditions In Adults” Progress In Nutrition Supplement Volume 4 January 2002). The journal is not listed on PubMed, Science Citation Index Expanded, or any other resources listing legitimate scientific journals. The accusation has been made that it is a fake journal funded by Garden of Life, but I cannot confirm this. In any case, it is clearly not a legitimate peer-reviewed scientific publication, and the author is a chiropractor who seems to publish predominantly in chiropractic journals and newsletters, not real science journals.

A bit more investigation into Mr. Rubin explains pretty clearly his lack of respect for legitimate scientific research or academic credentials. He is the paragon of faith-based medicine whose books, including The Maker’s Diet and Patient Heal Thyself, detail his belief that his own GI disease was cured through a combination of prayer and changes in diet based on “biblical principles.” As he puts it:

“My father had just gotten through telling me he had spoken to an eccentric nutritionist on the phone. My father didn’t want me to get my hopes up so he had investigated the man’s program himself. The nutritionist told my father he believed I was ill because I was not eating the diet of my ancestors, based upon Biblical principles.

When my father told me about all of this, naturally, I was curious…It fit into my belief system. In an effort to start all over, I took myself off all nutritional products and read the Bible to see what people ate thousands of years ago. I also learned that the longest living cultures in the world had one thing in common: they consumed living foods that abounded with beneficial microorganisms.

A few weeks later, I got on a plane, still bound to my wheelchair, and headed for southern California to live closer to the man who would teach me how to eat from the Bible. After integrating into that particular nutritionist’s program some of my own findings about nutrition and health from the Bible I saw some improvement…During my forty days and nights of parking my motor home close to the beach, I prayed, listened to music and planned everything around buying, preparing and eating my food…The combination of the Biblical diet and the HSOs had restored my health.”

The use of science to try and justify Mr. Rubin’s unscientific nutritional theories are pure marketing, taking advantage of the respectability that real science has earned through the results it produces. His approach is ultimately based, as so much CAM is, on personal revelation, and supported primarily through anecdote and testimonial. His books, his Garden of Life company, his Biblical Health Institute, and all the other pieces to his lucrative nutrition business are paradigms of snake oil marketing.  

Such a marketing approach can turn a potentially legitimate, if not yet ready for primetime, therapy like probiotics into pure quackery. If you can’t trust Mr. Rubin’s claims about his own credentials or the research evidence behind his products, why should you have any faith in his products themselves, even if they claim to be something potentially useful like probiotics? CAM marketers like to attack the honesty and ethics of mainstream medical product manufacturers, such as pharmaceutical companies and commercial pet food makers. And all too often, there are real reasons to be skeptical of these industries. But for all that, they have an established, public record of legitimate science behind many of their products, often thanks to vigorous government regulation requiring it. Companies like Garden of Life illustrate why the unregulated supplement industry (aka Big CAM) is not only not entitled to the assumption of better ethics that they often receive, but it quite likely gets away with even more ethically questionable practices than the mainstream medical and diet industries, which are at least better supervised and regulated. I do not often feel justified in prescribing probiotics, but when I do I certainly have no intention of using a product such as Primal Defense marketed by a man who not only bases clearly unscientific advice and products on personal divine revelation but who seems to have no discomfort promoting his ideas and products with obvious and egregious deceit.

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Dr. Shawn on Alison Averis’ Essay Fooling Yourself

The tireless promoter of “natural” veterinary medicine (whatever that is) and himself, Dr. Shawn Messonier, has applied his characteristic fuzzy logic and love of strawmen and misleading hyperbole to a recent guest post by Alison Averis on Fooling yourself: An example of how to fool yourself and how the placebo effect can work in animals. I shall reproduce his post below, with appropriate commentary and clarification (in bracketed, boldface type).

“I recently came across a post on another blog purporting to show that there is no proof that natural/alternative therapies work. [Actually, actually reading Alison’s post will make it clear that this is not the point of it at all. Throughout his essay, Dr. Shawn seems unable to distinguish between an anecdote used appropriately as an illustration and example of a phenomenon, and his preferred use of it as proof of something. Alison’s story was a parable illustrating how easy it is for one’s expectations to color one’s judgment about the efficacy of a therapy not evaluated in an objective, scientific way, not a statement or proof that “natural/alternative” therapies do not work.] This particular blog is devoted to debunking any therapy that falls outside the mainstream. [Actually, this blog is devoted to, as it says at the top of the page, taking a “Science-Based Look at Complementary and Alternative Medicine.” I am happy to validate any non-mainstream therapy that can be demonstrated to be effective in an appropriately scientific way, and I am equally happy to condemn any mainstream therapy that cannot.] The writer of this blog constantly seeks to show that there is no proof that any natural therapy ever works or helps anyone or any pet. [strawman and flagrant demonization]

The post I read was submitted by a reader of this particular blog. Briefly, she shared the following information in her post.
An “alternative therapist” told the owner of a horse that she would “work on” the horse for free if the owner would give her feedback on how the horse performed following the “free therapy session.” Unknown to the owner, the “therapist” never worked on the horse but led the owner to believe she had done so.

The day following the supposed “therapy,” the owner was happy to report that the horse actually “rode better than normal.” The writer of the blog used this one example to prove that natural therapies don’t work and that the reason the owner thought the horse rode better was simply due to the power of suggestion, or the placebo effect. [Again, the example was never purported to prove that “natural therapies,” or even the specific therapy referred to, don’t work. It was intended to illustrate how subjective, uncontrolled observations are an unreliable basis for making a judgment on what works and what doesn’t.]

While this was an interesting post to read, and it can easily deceive people into thinking that this one simple experiment proved that all natural therapies only work by the placebo effect, a more careful examination of the post leaves a lot to be desired.

First, I don’t know what an “alternative therapist” is or what one does. I assume the writer of this blog is referring to some sort of physical therapy such as massage therapy, but that is never explained.

Second, there’s a big difference between someone who claims to be an “alternative therapist” and a licensed doctor trained in integrative medicine. [How, exactly, does one get “licensed” to practice “integrative medicine?” This is a buzzword that simply means the use of unproven therapies alongside scientifically validated ones, and there is no process by which one becomes licensed to do this.]

Third, this particular website on which the blog appears always chastises alternative medicine for the lack of proof for alternative therapies since there are so few well controlled, double-blind placebo-controlled studies. [I have rebutted this charge of relying only on double-blind placebo controlled trials before HERE, yet Dr. Shawn continues to state the falsehood that I rely solely on such evidence.] It’s interesting that this website now uses an example of a poorly designed “study” (if an observation of one patient even constitutes a study) to prove that no natural therapies ever work! [Yet again, the hypocrisy that he gleeful implies is not present, despite his inability to distinguish an example from a proof.]

Fourth, the observation in this case was entirely subjective rather than objective. Rather than using an owner’s observation that the horse “rode better” after a particular therapy, why not use a more objective measurement such as gait analysis or forced plate analysis? In my practice, I can objectively measure things such as a pet’s blood pressure or blood count and easily determine if my therapy (conventional or natural) is working. This can totally eliminate the subjective assessment an owner may make in determining if a pet simply “feels better.” [I would be very interested in how much “objective” measuring of outcomes Dr. Shawn actually does. He seems to imagine he can “eliminate” subjective owner assessments in his practice, but I find this hard to believe. He routinely claims better outcomes for his patients with cancer, for example, than those possible through scientific medicine, yet I am unaware of any formal, scientifically controlled or objective research he has published on the subject, so I wonder how exactly he makes his assessments of his interventions more objective and independent of owner history than the rest of us in clinical practice.]

Fifth and finally, the same “conclusion” could easily be reached in this case if a conventional drug had been used rather than an alternative therapy. For example, suppose a doctor told the same horse owner that he was going to give the horse a pill which would improve its performance. But suppose the doctor secretly did not give the horse the medication but the owner still reported that the horse “rode better” the next day. If we follow the blogger’s (lack of) logic, we have to draw the same conclusion-namely that this one example proves that conventional drug therapy doesn’t work! [No, as I’ve made clear, and as should be obvious from reading the post, the conclusion we would draw would be that the owner report of how the horse performed subsequent to the sham therapy, be it conventional or alternative, is not a reliable assessment of the efficacy of the therapy. The point is that we must have a better level of evidence, and my evaluations of alternative practices such as those advocated by Dr. Shawn is intended to identify whether such evidence is or is not available. He is the one who routinely relies on his personal experiences and intuition and anecdotes as evidence to justify implausible or simply “made up” theories and practices. The whole purpose of this blog is to do better than this sloppy and outdated approach, not to replicate it in favor of or in opposition to any particular therapy.]

It’s interesting how much hatred and negativity one encounters among people who don’t like natural/alternative medicine. [It is also interesting to see how reasoned and civil criticism and a call for real evidence rather than simply opinion is identified as “hatred and negativity.”] To use one example as this blogger has done as universal proof that integrative medicine doesn’t achieve successful results is ludicrous and deceiving. [And, fortunately, not at all what has been done with this example] Fortunately, it’s easy to see through all the hypocrisy in this blog and understand the real goal of people who write this rubbish-destroy your choice in determining what kind of therapy you would like for you, your family members, and your pets. [Wow, “rubbish.” There’s a polite and thoughtful critique for you. As for the question of choice, I’ve addressed this bit of misdirection before. Offering as alternatives treatments which have not been demonstrated to be safe or effective, or which have actually been clearly demonstrated not to be so, is not offering choice–it is offering false hope at best and lies at worst, and these are not what our patients or clients deserve from us.]”

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The Mysterious Vanishing Placebo Effect?

I have written about the placebo effect before, but a recent update to a Cochrane review entitled Placebo Interventions for All Conditions has prompted me to revisit the subject. It has been clear for some time that the so-called placebo effect is not an example of the power of the mind to overcome disease. There is no evidence that therapies which have no measurable biological affect can truly alter the progression or outcome of an illness. No matter how you feel when given a deliberate placebo or an inert CAM therapy, you don’t live longer, your tumor doesn’t get smaller, you blood sugar doesn’t become normal, and the objective effects of your disease on your body don’t change.

What has seemed reasonable to me in the past is the idea that there might be real benefits in terms of subjective symptoms, such as pain or nausea, attributable to placebo effects. However, I am a little less confident of that in light of this recent review.

The review was a metanalysis of clinical trials which included both placebo and no treatment groups. As expected, no significant clinical effects were found for any objectively measurable variable. However, even in the case of subjective variables like pain and nausea, the best the authors could say was, “in certain settings placebo interventions can influence patient-reported outcomes, especially pain and nausea, though it is difficult to distinguish patient-reported effects of placebo from biased reporting.”

For pain, some trials reported little or no effect, and those that reported a large effect were all conducted by the same group of researchers, which raises suspicions about the reliability of the findings. Findings for most other subjective measures either showed no benefit from placebo, or effects that varied enormously from one study to another, suggesting differences in the studies were responsible for differences in the findings. If the placebo effect were a consistent, reliable phenomenon one would expect it to show up about the same regardless of who is studying it.

The metanalysis also found that how much benefit patients seemed to get from placebo treatments depended heavily on whether they thought they might be getting a placebo treatment. Inert treatments worked better in trials where the subjects were told that no placebo would be given.

These findings and others like them make it seem very likely that the placebo effect is less a feature of the human mind than it is an artifact of  clinical trial design, a conglomeration of biases and measurement errors rather than mind over matter. The better one controls for biased reporting of effects, the less effect one sees. This is not how the results look when one studies an unequivocally effective therapy, even one involving subjective symptoms, such as NSAIDs for arthritis pain. Effects from real therapies are consistently seen in different studies by different researchers, and they do not disappear when the trials become better controlled for bias.

Of course, if someone tells you they have pain or nausea, and then you give them a placebo and they say they have less pain or nausea, can you really say the effect isn’t real? If these phenomena are ultimately subjective, than regardless of the biological events underlying them the perceptions of the sufferer must be the critical determinant of benefit. Still, most of the research on placebos and sham therapies suggests that when well-designed studies are conducted, these benefits are small and do not reach anything like the level of clinical significance of true therapies for these symptoms. And, as I have discussed before, taking advantage of what benefit may occur due to placebo effects requires successfully deceiving the patient, which raises significant ethical concerns.  The lesson of this review seems to be that placebo effects may turn out to be mostly illusory, artifacts of inadequate study design, and we should be hesitant to rely on them for treatment of any clinically significant symptoms.

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What Scientists Say and What the Public Hears

There are many barriers to public understanding of science and scientific research, ranging from low levels of science literacy in the general population to frequently  poor communication skills among scientists. I recently ran across a pithy summary of some common technical jargon used, in this example, in discussing vaccine safety, and the corresponding interpretation non-scientists are likely to give these terms. I have adapted it slightly from the source, an excellent book on the question of vaccine safety titled Do Vaccines Cause That?! A Guide for Evaluating Vaccine Safety Concerns by Martin G Meyers and Diego Pineda. Many of these kinds of confusion come up a lot when I am discussing the scientific evaluation of medical therapies with non-scientists, and they are a perennial source of confusion and frustration for all concerned. I’m sure you can all think of many others, so feel free to add as many as you can to the list and I will eventually try to compile something more comprehensive.

Expression/Word What Scientists Mean What the Public Hears
Adverse event Something that occurs at the same time as a medical intervention, which may or may not be related Something bad caused by the intervention
Bias Systematic error that could lead to mistaken conclusion. Not having an open mind
Favors rejection of the hypothesis The data suggest the hypothesis isn’t true, but you can never wholly prove a negative We still don’t know
The findings won’t go away We couldn’t find an alternative explanation We’re trying to fudge the data
Inadequate to accept or reject the hypothesis The data do not allow a definitive statement We don’t know
Naïve Not previously exposed to X Unsophisticated, stupid
Plausible Theoretically possible Likely, probably true
Relative risk The difference in risk between two groups or populations or conditions in an experiment The risk
Safe Insignificant risk No risk
Significant Not due to chance Important, real
Not significant Due to chance Unimportant
No evidence for X No definitive conclusion about X is possible X may be true we just can’t prove
No evidence against X No  definitive conclusion about X is possible X probably is true
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The Dunning-Kruger Effect: Why incompetence is blind to itself.

“The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt.”
Bertrand Russell

“Ignorance more frequently begets confidence than does knowledge.”
Charles Darwin

“It is one of the essential features of such incompetence that the person so afflicted is incapable of knowing that he is incompetent.”
William Ian Miller

I recently stumbled across an article on the Dunning-Kruger Effect, a theory of psychology that claims, “…the skills that engender competence in a particular domain are often the very same skills necessary to evaluate competence in that domain-one’s own or anyone else’s…” What this means in ordinary terms, is that while we all overestimate our own knowledge and skills, the less competent we are at something the more will will overestimate our abilities.

The original article is Unskilled and unaware of it: How difficulties in Recognizing one’s own incompetence lead to inflated self-assessment, and it is well worth a read. The authors conducted a number of experiments on that paradigm of Guinea pigs, the undergraduate psychology student. They gave them tests of social skills (recognizing how funny jokes were compared to a standard of professional comedians’ assessment) and cognitive skills (English grammar and logical reasoning), and they evaluated the accuracy of the subjects’ self-assessment compared with their actual performance. Those in the bottom quartile were most likely to overestimate their skills by the largest amount.

Subsequent tests and analyses indicated that this inaccurate self-assessment was tied to the lack of the same skills needed to perform well on the tests. Those subjects in the top quartile consistently underestimated their performance, but when exposed to representative samples of other subjects’ tests, these top performers were able to adjust their self-assessment appropriately, whereas the bottom quartile subjects did not correct their inaccurate self-assessment based on being able to see directly how their peers performed.

How is this relevant to medicine? Well, in the obvious way that the very people who most need to improve their knowledge and skills and those who are least likely to be able to see that they need this improvement. We all rationalize our failures under the pressure of cognitive dissonance, and we all assess ourselves more charitably than we assess others. But the Dunning-Kruger Effect suggests that those of us with the weakest skills, whether it be in medicine specifically or in the kinds of critical thinking necessary to separate truth from nonsense, we are also the least likely to be able to recognize our own deficiencies.

There is some good news, however. The study also looked at whether or not the least competent subjects could improve the accuracy of their self-assessment. As it turns out, if you make them more competent, by training them on the skills they are being tested on, they also become better able to accurately gauge their own performance. That’s a strong argument for widespread teaching of critical thinking skills and the skeptical outlook, since it suggests we can do better in both our assessments of the world around us and our judgments of our own capabilities.

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