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Marijuana and cancer – Sanjay Gupta’s anecdotes are not science

Editor’s note–this article has been updated and included into a multi-part series on marijuana and medicine. Check it out there. 

Unless you were hiking in the Amazon River jungles, with no access to the internet or American TV, you probably have heard that CNN’s chief medical correspondent, Dr. Sanjay Gupta, changed his mind about marijuana (or “weed” as he keeps saying). Of course, this has become big news, because he’s such a “respected doctor” (why is that? Because he’s on TV?), and because a few years ago he was vociferously anti-cannabis.

I have no doubt that Dr. Gupta’s “conversion” to being pro-weed is genuine (and that his previous stance of anti-weed was similarly authentic), but we need to weed out what is real and what’s just smoke about his comments. His first major point about cannabis* was that the United States Drug Enforcement Agency (DEA) considers marijuana to be a Schedule 1 drug, which is defined as “drugs with no currently accepted medical use and a high potential for abuse.”

Dr. Gupta thinks this classification is ridiculous, and on the surface, many people, even those who are not devoted pot smokers, would probably agree. However, this is a political discussion, at least in the USA, and it is hardly a medical/scientific one. The chances of any political party having the fortitude to correct this classification is about as close to 0 as you can get, without actually stating that there is a 0 chance. But if Gupta wants to make a big deal of this, or that he’s so self-centered that he thinks he’ll change the mind of politicians, more power to him. But for me as a skeptic, it is not the most important thing he says.

In his article, he mentions a young girl who “started having seizures soon after birth. By age 3, she was having 300 a week, despite being on seven different medications. Medical marijuana has calmed her brain, limiting her seizures to 2 or 3 per month.” This is simply an anecdote of no quality whatsoever. Did he thoroughly investigate her case to determine if the number of seizures actually went down? Do we know that cannabis has anything to do with the change? Is this nothing more than a Post hoc ergo propter hoc fallacy, that just because she consumed cannabis and the seizures decreased does not mean anything about cannabis’ causative properties with regards to this type of seizure. And then, Dr. Gupta continues with the anecdotes by stating, “I have seen more patients like Charlotte first hand, spent time with them and come to the realization that it is irresponsible not to provide the best care we can as a medical community, care that could involve marijuana.” Why do these TV doctors (like Dr. Oz) think that their anecdotes are better than anyone else’s.

Anecdotes are useless because they aren’t controlled, because they are subject to all levels of bias, and because these stories aren’t peer-reviewed. In other words, anecdotes have no value in science-based medicine. Anecdotes do have value in formulating testable scientific hypotheses, but assuming that anecdote=data, and more anecdotes=more data is simply pseudoscientific. I don’t care what Sanjay Gupta writes or says publicly, but providing these stories as “evidence” that marijuana has a medical benefit is essential like telling me that he observed homeopathy (which is just water) working. It’s laughable.

Read More »Marijuana and cancer – Sanjay Gupta’s anecdotes are not science

The one study to rule them all–the vaccine denier’s dream

If you spend any time in the “debate” (actually, one side has scientific evidence and the antivaccination side denies all science, so to avoid falling for a false equivalency, debate gets scare quotes), you’ll hear every dumb argument to deny science. But one thing that you’ll see repeatedly from the vaccine deniers is that they would support vaccinations if there were better clinical trials.

The problem with the vaccine denier’s clinical trial proposals is that they are a moving target, relying on a form of the Argument from ignorance, claiming that if we can’t absolutely “prove” that vaccines are safe, then it must be absolutely unsafe. For example, there are dozens of articles, including one of the latest (published here and discussed here).

The actual process for vaccine clinical trials.

The actual process for vaccine clinical trials.

My good friend Allison Hagood, co-author of Your Baby’s Best Shot: Why Vaccines Are Safe and Save Lives, wrote a commentary about the antivaccine community’s perfect clinical trial. Follow along! (Allison’s commentary is presented in whole, but I’ve edited the formatting and added links where necessary).

Read More »The one study to rule them all–the vaccine denier’s dream

Court says Freedom of Speech applies to Big Pharma Sales Reps

pills and pill bottlesIn a strange decision, the United States 2nd Circuit Court of Appeals, which has jurisdiction over  ConnecticutNew York, and Vermont, ruled that a drug sales representative who promotes “off-label” uses of a particular drug is exercising their “freedom of speech.” The Court decided in a 2-1 vote, in United States v. Caronia (pdf), that the criminal conviction of Alfred Caronia, a former sales representative for a pharmaceutical company, be vacated. The case was an appeal of the sales representative’s conviction for promoting an off-label use of the drug Xyrem, which is approved for treatment of narcolepsy. The Court stated that “we construe the FDCA as not criminalizing the simple promotion of a drug’s off-label use because such a construction would raise First Amendment concerns.”

The Court also found that the FDA allows off-label use by physicians, but “prohibits the free flow of information that would inform that outcome,” while “the government’s prohibition of off-label promotion by pharmaceutical manufacturers provides only ineffective or remote support for the government’s purpose.” The Court also ruled that it construes “the misbranding provisions of the FDCA as not prohibiting and criminalizing the truthful off-label promotion of FDA-approved prescription drugs.”  It also stated “that the government cannot prosecute pharmaceutical manufacturers and their representatives under the FDCA for speech promoting the lawful, off-label use of an FDA-approved drug.”Read More »Court says Freedom of Speech applies to Big Pharma Sales Reps

Chronic Lyme disease–myth or science?

This article has been substantially updated and re-published. Please view that article and comment there.

Lyme disease is an infectious disease caused by at least three species of bacteria belonging to the genus Borrelia. Of the three species, Borrelia burgdorferi is the main cause of Lyme disease in North America, whereas Borrelia afzelii and Borrelia garinii are more prevalent in Europe. The disease is named after the towns of Lyme and Old Lyme, Connecticut, where a number of cases were initially identified in 1975.

Borrelia is transmitted to humans when bitten by infected ticks belonging to a few species of the genus Ixodes, called “hard bodied” ticks. Although deer ticks, Ixodes scapularis, Ixodes pacificus, or Ixodes ricinus, are commonly considered to be the vectors for Borrelia infection, some of the other Ixodes species can transmit the disease.

The initial symptoms of Lyme disease include feverheadachefatiguedepression, and a circular skin rash called erythema migrans (EM). If the Borrelia infection is not treated quickly, later symptoms may involve the joints, heart, and central nervous system. In general, the infection and its symptoms can be treated, if started early, by antibiotics. Lyme disease is the most common tick-borne disease in the United States.

Read More »Chronic Lyme disease–myth or science?

“Homeopaths without Borders” going to Haiti to provide water

Yes, there is a group called Homeopaths without Borders. Apparently, the group that does lifesaving work across the world, Doctors without Borders, are too busy, utilizing real evidence-based medicine with real medications, risking their own lives, and doing great works, to be worried about homeopathy, a pseudoscientific concept, even if this group steals their imprimatur without shame.

Homeopaths without Borders are sending their water magicians to Haiti, a country that has had to suffer so much during the past few years. During their time their, “the team will be in Port-au-Prince to complete the final session of the Fundamentals Program—a foundational curriculum in homeopathic therapeutics incorporating theoretical and clinical training.” Clinical training on the poor residents of Haiti? Have they not suffered enough?Read More »“Homeopaths without Borders” going to Haiti to provide water

The Placebo Effect–Myth vs. Science


There has been a large uptick in interest about the so-called placebo effect, mostly from the complementary and alternative junk medicine (CAM) crowd. Evidently, they feel that being equivalent to doing nothing is good enough to be real. A recent article in the Wall Street JournalWhy Placebos Work Wonders, is indicative of this recent pro-placebo point-of-view.  

What exactly is the placebo effect? The definition is often misused, implying some beneficial effect from a sugar pill or sham treatment. But in medicine, a placebo is actually a failure. If a new pharmaceutical, procedure or medical device shows no difference in efficacy compared to a placebo, then it is rejected.  But the CAM-pushing herd thinks that proves its a success when one of its potions and lotions is equivalent to a placebo. What? A failure of a modality in evidence-based medicine is somehow converted into a successful product in the CAM world?

Read More »The Placebo Effect–Myth vs. Science

Science does not require faith

Science denialists, whether they are creationists, global warming deniers, or anti-vaccinationists, are pseudoskeptics, who reject or ignore vast amounts of real evidence, just to maintain their point of view. Discussions with these individuals are generally frustrating because the denialists base their arguments on a very limited amount of education or background. As I’ve said before, at least with respect to vaccine denialism, they have spent no more than a few hours of research on the internet. Then using logical fallacies, whether it’s ad hominems, or appeals to nature, or  cherry picking data, they attempt to discredit the vast scientific and medical body of work, patting themselves on the back for their incredible skills in winning a scientific argument. Of course, most of the science against which they’ve been arguing has been performed by individuals with years of scientific education, training and professional research.

Is this research perfect? No, it isn’t. Nature has reported that a Japanese anesthesiologist, who authored over 200 “peer-reviewed” papers, is suspected of fraud on an epic scale. Over half of his papers are being retracted, and he has been dismissed from his faculty position in Japan. How he got away with this level of fraud is subject to a long discussion in the Nature article, but suffice it to say, there was a massive breakdown of the peer-review system at the level of his own university (which may be cultural in Japan) and by the way he published in a wide variety of journals, some of lower quality. I constantly point out that there are differences in journals, based on their impact factor (which is one way of measuring the amount of influence a journal has within the scientific community). However, and this is important, science is self-correcting, and in this case, it has corrected itself. Based on this one story, it would be insane to assume that ALL science is fraudulent. Even assuming a significant minority of science is fraudulent would be improper and not supported by any amount of evidence. Read More »Science does not require faith

Circumcision–separating science from opinion

Circumcision is one topic that certainly brings up more emotion than just about any medical procedure. In fact, the same level of rhetoric is used for and against circumcision that one hears with regards to vaccines, or even abortion. Recently, the city of San Francisco attempted to ban the practice, but a judge ruled that only the state could regulate medical procedures. During the summer, a German court banned circumcision for religious purposes, though a German court banning a Jewish practice must have blown up irony meters across the world.

In any discussion about circumcision, there is general consensus that female circumcision, or female genital mutilation, is an abhorrent non-medical procedure that is simply an anti-female procedure in many male-dominated societies. We’re not talking about that, and any comparison between male and female circumcision is a strawman argument. It is also clear that part of the anti-circumcision argument centers around secularism and atheism, because male circumcision is integral to both the practice ofJudaism and Islam. That is a valid argument, and there could even be a concern that unskilled individuals performing ritual circumcisions could cause serious complications. I personally could care less about religious rituals as long as they don’t harm anyone, so this is where we need to determine what the evidence tell us. Read More »Circumcision–separating science from opinion

The importance of Cochrane Reviews to science based medicine (updated)

Cochrane Collaboration Copyrighted from the Cochrane Collaboration

The Cochrane Collaboration is a critically important source in evidence-based medicine, and a useful tool in providing analytical evidence that can debunk pseudoscientific beliefs. Cochrane’s goal is to organize research data and publications in an logical way that helps physicians and researchers make appropriate decisions about a proposed new therapy, medication or clinical idea. Cochrane Reviews are:

…are systematic reviews of primary research in human health care and health policy, and are internationally recognised as the highest standard in evidence-based health care. They investigate the effects of interventions for prevention, treatment and rehabilitation. They also assess the accuracy of a diagnostic test for a given condition in a specific patient group and setting.

Each systematic review addresses a clearly formulated question; for example: Can antibiotics help in alleviating the symptoms of a sore throat? All the existing primary research on a topic that meets certain criteria is searched for and collated, and then assessed using stringent guidelines, to establish whether or not there is conclusive evidence about a specific treatment. The reviews are updated regularly, ensuring that treatment decisions can be based on the most up-to-date and reliable evidence.Read More »The importance of Cochrane Reviews to science based medicine (updated)