Articles

Archive for Science and Medicine

Short Attention Span SBM

The bar on this blog is set high. The entries are often complete, with no turn left unstoned. Yet, not every topic needs the full monty with every post. The blog has extensive evaluations on many topics, and new medical literature doesn’t require another complete analysis. Many new articles add incrementally to the literature and their conclusions need to be inserted into the conversation of this blog, like a car sliding into heavy traffic. My eldest son just received his driver’s license, and car metaphors are on my mind. As are crash metaphors and insurance metaphors.

So in response to this need, a need only recognized by me, I give you Short Attention Span SCAM. Occasionally I will summarize a few recent studies and their key points as they relate to prior posts at SBM.

(more…)

Posted in: Acupuncture, Herbs & Supplements, Science and Medicine, Vaccines

Leave a Comment (18) →

Christiane Northrup: more bad medicine

A question popped up on facebook the other day about Dr. Christiane Northrup, an OB/GYN who has been a frequent guest on Oprah.  I hadn’t heard much about her for a while, but a foul taste still lingered from previous encounters with her work.  So I went over to her website to see what fare she’s currently dishing up.  It isn’t pretty. (Cached version).

This month’s news item is titled “Angst Over Not Vaccinating Children is Unwarranted.” Regular readers will be expecting a typical antivax screed, and they won’t be disappointed, but I’d like to highlight some of the propaganda techniques Northrup uses to advance her dangerous lies.

She begins her story with this:

In June, 2010 there was an outbreak of pertussis (whooping cough) in California that reporters were calling the worst epidemic in 50 years.

There are two problems with this opening sentence.  The outbreak is ongoing, and it’s not “reporters” who are calling it “the worst epidemic in 50 years.”  The California Department of Public Health reports that the state has seen the largest number of cases in the last 55 years.  Of course the state was much smaller 55 years ago, so for comparison they give us an incidence rate: 10.3 cases/100,000 in 2010, the highest rate in 48 years (when the rate was 10.9 cases/100,000).  So far in California, there have been 9 deaths.  All of the deaths were in babies eight of whom were unvaccinated and one of whom had been vaccinated only days before becoming ill, not early enough to develop immunity.
(more…)

Posted in: Science and Medicine

Leave a Comment (57) →

CFLs, Dirty Electricity and Bad Science

Governments and environmental advocates are promoting compact fluorescent lightbulbs (CFLs) as a way of reducing electricity use, saving money, and reducing our carbon footprint. CFLs are not a perfect technology – when turned on they take a moment to fully brighten and they contain a small amount of mercury which requires special procedures for disposal. CFLs are likely also to be a transitional technology, as more energy efficient light sources (such as LEDs) are already coming onto the market.  But CFLs are a safe and energy efficient alternative to incandescent bulbs.

It seems, however, with any new technology comes a wave of internet fearmongering, and CFLs are now a prime target. YouTube videos are circulating claiming that CFLs cause headaches, mercury toxicity, a host of symptoms from electromagnetic sensitivity, and something called “type 3 diabetes.”  Let’s take a look at the claims and the science.

Mercury in CFLs

There is a small amount of mercury in each CFL, necessary for the function of the bulb, about 4mg on average, with some newer bulbs having as little as 1.4mg. There is no exposure to mercury from using CFLs, as long as they are not broken. Even if a bulb is broken the exposure to mercury is negligible, far less than eating a tuna fish sandwich. But still, there are recommended procedures for cleaning up and disposing of a broken bulb to further minimize exposure, such as not using a vacuum, and ventilating the area. These procedures represent the cautionary principle in action, but make it easy to fearmonger about the risks of the mercury in the bulb.

(more…)

Posted in: Public Health, Science and Medicine

Leave a Comment (53) →

How not to consult your biostatistician before doing an experiment

A friend of mine at work sent this video to me in great amusement.

I just hope he wasn’t making a comment on my behavior when it comes to dealing with our biostatisticians. I have, of course, seen investigators approach biostatistians this late in the game. Not that I’ve ever flirted with this sort of behavior, of course. At least the researcher in the video above actually consulted the biostatistician before doing the experiment, rather than after doing an experiment with inadequate statistical power to answer the question asked. On the other hand, I guess it doesn’t matter if the researcher doesn’t listen, does it?

Posted in: Humor, Science and Medicine

Leave a Comment (8) →

Evidence-Based Medicine, Human Studies Ethics, and the ‘Gonzalez Regimen’: a Disappointing Editorial in the Journal of Clinical Oncology Part 2

NB: If you haven’t yet read Part 1 of this blog, please do so now; Part 2 will not summarize it.

At the end of Part 1, I wrote:

We do not need formal statistics or a new, randomized trial with a larger sample size to justify dismissing the Gonzalez regimen.

In his editorial for the JCO, Mark Levine made a different argument:

Can it be concluded that [the] study proves that enzyme therapy is markedly inferior? On the basis of the study design, my answer is no. It is not possible to make a silk purse out of a sow’s ear.

That conclusion may be correct in the EBM sense, but it misses the crucial point of why the trial was (ostensibly) done: to determine, once and for all, whether there was anything to the near-miraculous claims that proponents had made for a highly implausible “detoxification” regimen for cancer of the pancreas. Gonzalez himself had admitted at the trial’s inception that nothing short of an outcome matching the hype would do:

DR. GONZALEZ: It’s set up as a survival study. We’re looking at survival.

SPEAKER: Do you have an idea of what you’re looking for?

DR. GONZALEZ: Well, Jeff [Jeffrey White, the director of the Office of Cancer Complementary and Alternative Medicine at the NCI—KA] and I were just talking a couple weeks ago. You know, to get any kind of data that would be beyond criticism is—-always be criticism, but at least three times.

You would want in the successful group to be three times — the median to be three times out from the lesser successful groups.

So, for example, if the average survival with chemo, which we suspect will be 5 months, you would want my therapy to be at least — the median survival to be at least 15, 16, 17 months, as it was in the pilot study.

We’re looking for a median survival three times out from the chemo group to be significant.

Recall that the median survival in the Gonzalez arm eventually turned out to be 4.3 months.

(more…)

Posted in: Cancer, Clinical Trials, Health Fraud, Medical Academia, Medical Ethics, Politics and Regulation, Science and Medicine

Leave a Comment (30) →

Evidence-Based Medicine, Human Studies Ethics, and the ‘Gonzalez Regimen’: a Disappointing Editorial in the Journal of Clinical Oncology Part 1

Background: the distinction between EBM and SBM

An important theme on the Science-Based Medicine blog, and the very reason for its name, has been its emphasis on examining all the evidence—not merely the results of clinical trials—for various claims, particularly for those that are implausible. We’ve discussed the distinction between Science-Based Medicine (SBM) and the more limited Evidence-Based Medicine (EBM) several times, for example here (I began my own discussion here and added a bit of formality here, here, and here). Let me summarize by quoting John Ioannidis:

…the probability that a research finding is indeed true depends on the prior probability of it being true (before doing the study), the statistical power of the study, and the level of statistical significance.

EBM, in a nutshell, ignores prior probability† (unless there is no other available evidence) and falls for the “p-value fallacy”; SBM does not. Please don’t bicker about this if you haven’t read the links above and some of their own references, particularly the EBM Levels of Evidence scheme and two articles by Steven Goodman (here and here). Also, note that it is not necessary to agree with Ioannidis that “most published research findings are false” to agree with his assertion, quoted above, about what determines the probability that a research finding is true.

The distinction between SBM and EBM has important implications for medical practice ethics, research ethics, human subject protections, allocation of scarce resources, epistemology in health care, public perceptions of medical knowledge and of the health professions, and more. EBM, as practiced in the 20 years of its formal existence, is poorly equipped to evaluate implausible claims because it fails to acknowledge that even if scientific plausibility is not sufficient to establish the validity of a new treatment, it is necessary for doing so.

Thus, in their recent foray into applying the tools of EBM to implausible health claims, government and academic investigators have made at least two, serious mistakes: first, they have subjected unwary subjects to dangerous but unnecessary trials in a quest for “evidence,” failing to realize that definitive evidence already exists; second, they have been largely incapable of pronouncing ineffective methods ineffective. At best, even after conducting predictably disconfirming trials of vanishingly unlikely claims, they have declared such methods merely “unproven,” almost always urging “further research.” That may be the proper EBM response, but it is a far cry from the reality. As I opined a couple of years ago, the founders of the EBM movement apparently “never saw ‘CAM’ coming.”

(more…)

Posted in: Cancer, Clinical Trials, Medical Academia, Medical Ethics, Politics and Regulation, Science and Medicine

Leave a Comment (59) →

Chronic Fatigue Syndrome: Lots of Speculation

Humans love to find patterns in the world. Sometimes patterns exist, sometimes they are imaginary. Sometimes you can see a pattern that may be interesting and ignore its significance. As a resident I used to say that anyone who smokes three packs of cigarettes a day has to be schizophrenic, it was meant more as a joke, when, in fact, it was later discovered that tobacco helps ameliorate the symptoms of schizophrenia. I need to pay more attention.

Part of my job is to look for patterns as a key to the patients diagnosis. Diseases and pathogens tend to (more or less) cause reproducible signs and symptoms and looking for that pattern is often the most helpful clue towards finding the diagnosis. Of course things are never as easy as one would like, as you have to consider whether you are seeing common manifestations of a common disease, uncommon manifestations of a common disease, common manifestations of a uncommon disease and, the hardest, uncommon manifestations of an uncommon disease. When I have a complex or uncertain cause, I explicitly run through that, and other, litanies so I do not miss a unusual diagnosis.

Chronic Fatigue Syndrome (CFS) has, at least to my way of thinking, two patterns. I see the occasional CFS patient in clinic and, I hope, pay attention to their disease patterns. I keep in mind I may be seeing a pattern that does not exist, but looking for disease patterns is what doctors are trained to do.

(more…)

Posted in: Basic Science, Science and Medicine

Leave a Comment (27) →

Your disease, your fault

Earlier this week, my colleague Dr. Gorski explored a common theme in alternative medicine: the idea that all disease is preventable.  This implies that all disease has a discrete cause and that individual behavior can mitigate this cause.

If biology worked this way, my job as an internist would be very different.   Many people would love to believe that life is this predictable, and that they have that much control over their health, but they don’t.  Most disease represents the interaction of environment and genetics, and you can’t change your genes (with a few exceptions, of course).

It’s natural to want to be able to exert an impossible level of control over your health, but when unscrupulous charlatans (redundant redundancy alert!) play on these beliefs and fears, they can cause, rather than prevent problems.

(more…)

Posted in: Science and Medicine

Leave a Comment (62) →

Ghostwriting As Marketing Tool

An article in the latest issue of PLOS Medicine, The Haunting of Medical Journals: How Ghostwriting Sold “HRT”, details the use of ghostwriting as a marketing tool for pharmaceutical companies. It is a chilling discussion of how at least one pharmaceutical company, Wyeth, used the peer-reviewed literature as a method of distributing marketing messages to physicians.

The author, Adriane J. Fugh-Berman, details a practice that cuts at the heart of science-based medicine – the exploitation and distortion of the literature. The medical profession needs to jealously guard the legitimacy and purity of the peer-review process and the medical scientific literature. I am never one to gratuitously bash “Big Pharma” – this is often used as a method of casually dismissing inconvenient scientific evidence. But at the same time, pharmaceutical companies are in the business of making money. While they are a carefully regulated industry, some in the industry seek ways to skirt around regulations that limit their ability to market their products.

While most physicians consider themselves savvy with respect to pharmaceutical marketing, the story told by Fugh-Berman is one of profound naivete. I guess it should not be a surprise that some academics were bamboozled by expert salespersons who spent a lot of time and effort, apparently, figuring out ways to deceive and manipulate them. But now that the story is out, naivete is no longer an excuse. Here is what happened:

(more…)

Posted in: Medical Ethics, Pharmaceuticals, Politics and Regulation, Science and Medicine

Leave a Comment (32) →

Direct-to-Consumer Genetic Testing: Road Map or Tarot Cards?

A topic of growing interest (and concern) at SBM is laboratory and diagnostic test pseudoscience. Bogus tests are everywhere, and Kimball Atwood recently discussed several of them. But over the past several years, diagnostic tests have emerged that appear to be science-based and offer gene-level insights into your health. And these tests don’t even require a physician’s visit – just a swab of saliva and a credit card get you reams of information on your genetics, traits, and risks of dozens of diseases. It looks like the ultimate in consumer health information, with the potential to offer truly personalized treatment strategies. Companies like 23andme, deCODEme, and Navigenics all promise “genetic insights” to improve your health. How could this information be anything but helpful?

Personalized medicine describes medical practices that use information about a person’s genes, proteins, and environment to prevent, diagnose and treat disease. Science-based practice has routinely incorporated environmental advice (e.g., diet and exercise) into medical management. And there are a number of genetic tests in routine use that are well established, clinical validated, and are highly predictive of future outcomes, such as tests for Huntington’s disease and hereditary breast cancer.
(more…)

Posted in: Science and Medicine

Leave a Comment (19) →
Page 30 of 75 «...10202829303132...»