Whether it’s acupuncture, homeopathy or the latest supplement, placebo effects can be difficult to distinguish from real effects. Today’s post sets aside the challenge of identifying placebo effects and look at how placebos are used in routine medical practice. I’ve been a pharmacist for almost 20 years, and have never seen a placebo in practice, where the patient was actively deceived by the physician and the pharmacist. So I was quite surprised to see some placebo usage figures cited by Tom Blackwell, writing in the National Post last week:
The practice is discouraged by major medical groups, considered unethical by many doctors and with uncertain benefit, but one in five Canadian physicians prescribes or hands out some kind of placebo to their often-unknowing patients, a new study suggests.
The article references a paper in the Canadian Journal of Psychiatry which, sadly, does not have much of a web presence. The article continues:
In my recent review of Peter Palmieri’s book Suffer the Children I said I would later try to cover some of the many other important issues he brings up. One of the themes in the book is the process of critical thinking and the various cognitive traps doctors fall into. I will address some of them here. This is not meant to be systematic or comprehensive, but rather a miscellany of things to think about. Some of these overlap.
Everything is attributed to a pet diagnosis. Palmieri gives the example of a colleague of his who thinks everything from septic shock to behavior disorders are due to low levels of HDL, which he treats with high doses of niacin. There is a tendency to widen the criteria so that any collection of symptoms can be seen as evidence of the condition. If the hole is big enough, pegs of any shape will fit through. Some doctors attribute everything to food allergies, depression, environmental sensitivities, hormone imbalances, and other favorite diagnoses. CAM is notorious for claiming to have found the one true cause of all disease (subluxations, an imbalance of qi, etc.).
I saw a patient recently for parasites.
I get a sinking feeling when I see that diagnosis on the schedule, as it rarely means a real parasite. The great Pacific NW is mostly parasite free, so either it is a traveler or someone with delusions of parasitism.
The latter comes in two forms: the classic form and Morgellons. Neither are likely to lead to a meaningful patient-doctor interaction, since it usually means conflict between my assessment of the problem and the patients assessment of the problem. There is rarely a middle ground upon which to meet. The most memorable case of delusions of parasitism I have seen was a patient who I saw in clinic who, while we talked, ate a raw garlic clove about every minute.
“Why the garlic?” I asked.
“To keep the parasites at bay,” he told me.
I asked him to describe the parasite. He told me they floated in the air, fell on his skin, and then burrowed in. Then he later plucked them out of his nose.
At this point he took out a large bottle that rattled as he shook it.
“I keep them in here,” he said as he screwed off the lid and dumped about 3 cups with of dried boogers on the exam table.
To my credit I neither screamed nor vomited, although for a year I could not eat garlic. It was during this time I was attacked by a vampire, and joined the ranks of the undead. (more…)
This essay is the latest in the series indexed at the bottom.* It follows several (nos. 10-14) that responded to a critique by statistician Stephen Simon, who had taken issue with our asserting an important distinction between Science-Based Medicine (SBM) and Evidence-Based Medicine (EBM). (Dr. Gorski also posted a response to Dr. Simon’s critique). A quick-if-incomplete Review can be found here.
One of Dr. Simon’s points was this:
I am as harshly critical of the hierarchy of evidence as anyone. I see this as something that will self-correct over time, and I see people within EBM working both formally and informally to replace the rigid hierarchy with something that places each research study in context. I’m staying with EBM because I believe that people who practice EBM thoughtfully do consider mechanisms carefully. That includes the Cochrane Collaboration.
To which I responded:
We don’t see much evidence that people at the highest levels of EBM, eg, Sackett’s Center for EBM or Cochrane, are “working both formally and informally to replace the rigid hierarchy with something that places each research study in context.”
Well, perhaps I shouldn’t have been so quick to quip—or perhaps that was exactly what the doctor ordered, as will become clear—because on March 5th, nearly four months after writing those words, I received this email from Karianne Hammerstrøm, the Trials Search Coordinator and Managing Editor for The Campbell Collaboration, which lists Cochrane as one of its partners and which, together with the Norwegian Knowledge Centre for the Health Services, is a source of systematic reviews:
Calcium is good for us, right? Milk products are great sources of calcium, and we’re told to emphasize milk products in our diets. Don’t (or can’t) eat enough dairy? Calcium supplements are very popular, especially among women seeking to minimize their risk of osteoporosis. Osteoporosis prevention and treatment guidelines recommend calcium and vitamin D as an important measure in preserving bone density and reducing the risk of fractures. For those who don’t like dairy products, even products like orange juice and Vitamin Water are fortified with calcium. The general perception seemed to be that calcium consumption was a good thing – the more, the better. Until recently. (more…)
When an article is published in a medical journal, the authors must disclose any conflicts of interest. This is important, because even if they think owning stock in the drug company won’t influence their scientific judgment, we know that subtle biases can creep in to somehow affect the findings of studies. It has been shown that studies funded by drug companies are more likely to get positive results for their drug than studies funded by independent sources. Andrew Wakefield, author of the infamous retracted Lancet study suggesting a relationship between MMR vaccine and autism, was severely chastised for not disclosing that he received money from autism litigators and expected to earn a fortune from his own patented products if the MMR vaccine could be discredited.
I was recently contacted by an acupuncturist who plans to critique an article I wrote. It was a commentary in the journal Pain that accompanied a systematic review of systematic reviews of acupuncture by Ernst et al. For details of Ernst’s and my articles, see my previous post. He challenged my statement that I had no conflicts of interest to report. He apparently thinks I should have said I have a conflict of interest in that I am anti-CAM and anti-acupuncture. When he writes about my article, he plans to attack me for not declaring this alleged conflict of interest and he plans to set a good example with a conflict of interest statement of his own, divulging that he makes his living practicing acupuncture, has financial investments in it and many personal relationships, that his self-identity and prestige are dependent on his belief in acupuncture’s efficacy, and that he is biased towards constructivism and away from positivism. (I think this is a fancy way of saying he favors experience over the scientific method.) I agree that he has conflicts of interest, but was I wrong to say I had no conflicts of interest? I don’t think so. (more…)
After spending the first 21 years of life in New Jersey and Philadelphia, I ventured to the University of Florida for graduate school. For those who don’t know, UF is in the north-central Florida city of Gainesville – culturally much more like idyllic south Georgia than flashy south Florida.
It was in Gainesville – “Hogtown” to some – that I first encountered the analgesic powder. I believe it was BC Powder, first manufactured just over 100 years ago within a stone’s throw of the Durham, NC, baseball park made famous by the movie, Bull Durham. I remember sitting with my grad school buddy from Kansas City watching this TV commercial with hardy men possessing strong Southern accents enthusiastically espousing the benefits of BC. I looked at Roger – a registered pharmacist – and asked, “what in the hell is an analgesic powder?”
Despite the variety of health systems across hundreds of different countries, one feature is near-universal: We all depend on private industry to commercialize and market drug products. And because drugs are such an integral part of our health care system, that industry is generally heavily regulated. Yet despite this regulation, little is publicly known about drug development costs. But aggregate research and development (R&D) data are available, and the pharmaceutical industry spends billions per year.
Before we had EBM (evidence-based medicine) we had another kind of EBM: experience-based medicine. Mark Crislip has said that the three most dangerous words in medicine are “In my experience.” I agree wholeheartedly. On the other hand, it would be a mistake to discount experience entirely. Dynamite is dangerous too, but when handled with proper safety precautions it can be very useful in mining, road-building, and other endeavors.
When I was in med school, the professor would say “In my experience, drug A works better than drug B.” and we would take careful notes, follow his lead, and prescribe drug A unquestioningly. That is no longer acceptable. Today we ask for controlled studies that objectively compare drug A to drug B. That doesn’t mean the professor’s observations were entirely useless: experience, like anecdotes, can draw attention to things that are worth evaluating with the scientific method.
We don’t always have the pertinent scientific studies needed to make a clinical decision. When there is no hard evidence, a clinician’s experience may be all we have to go on. Knowing that a patient with disease X got better following treatment Y is a step above having no knowledge at all about X or Y. A small step, but arguably better than no step at all. (more…)
Editors Note: This is a guest contribution from two medical students, one from Chicago and one from Queensland. If you like their work, we’ll consider having them write more for us.
University of Queensland School of Medicine
Igor Irvin Bussel
Chicago Medical School
Rosalind Franklin University of Medicine and Science
In hopes of joining the SBM movement as medical students, we wanted to take aim at a topic that has yet been finely dissected a la Novella or logorrheicly dismembered a la Gorski. Having realized that a fellow medical student, Tim Kreider, is already addressing integrative medicine on campus, we decided that we would attempt to find a controversial topic that has yet to be addressed on SBM. A serendipitous question from a friend sent us on a mission to explore the pseudo-scientific underbelly of the web and science-based rationale of the claim that vitamin C can induce abortion.
The World Wide Web is a stranger place than we can ever imagine. Most users are aware that they can’t believe everything they read on the Internet, yet they often feel like Sherlock Holmes when they find an esoteric and isolated clue to their own unique health puzzle. Recently, we were asked if there was a connection between vitamin C, menstruation and abortion. We were caught off guard by the question, finding it such a strange connection to make. The story, it seems, is that our friend had come down with a cold and taken mega doses of vitamin C to stave it off (another false belief, but not the subject here). A couple of days later her menses began and she was surprised since it was 4 days earlier than normal. She of course turned to Dr. Google and was quickly provided with numerous sources indicating that indeed, vitamin C would induce the start of a menstrual cycle and can even act as a “natural” abortefacient and a substitute for the ‘morning after’ pill. Being a bit more keen than your average Dr. Google user, she was surprised and continued searching, trying to find evidence to contradict these claims. Alas, she found nothingexcept more sites parroting and corroborating the claim. Then she realized she knew a couple of medical students and asked us what we thought. Our literature review turned up a slew of websites using the standard repertoire of trite pseudo-scientific tactics. Any attempt to find a credible source, validated claim, or independent consensus proved futile.