Wednesday, October 12, 2016

Researching the Magic of Homeopathy


A Canadian academic, Dr. Mark Loeb, who is a respected infectious disease researcher who knows how to conduct high quality research, wants to study homeopathic nosodes. Nosodes are essentially homeopathic vaccines.

Tim Caulfield, a Canadian professor of health law and policy, thinks the study is misguided and unethical. The two are having a respectful public debate about the risks and merits of doing such a study.

David Gorski and I have actually published in the peer-reviewed literature on the broader question of studying alternative medicine: Clinical trials of integrative medicine: testing whether magic works? So we have both weighed in already on this debate, but since this is a major theme of science-based medicine I thought it was important to bring the discussion here as well.  It is an interesting dilemma worth discussing, and we are seeing that exact dilemma play out on the question of this specific proposed study.

Homeopathy is Pseudoscience

For quick background, both sides in this debate agree that homeopathy is 100% pseudoscientific nonsense. Homeopathy was invented by one person, Samuel Hahnemann, about 200 years ago. It was not based on any scientific research or knowledge base, it did not develop out of emerging knowledge of biology or physiology. It was simply invented out of whole cloth based loosely on the superstitious belief in sympathetic magic – the notion that substances contain a mysterious “essence” that can be transferred to the body and stimulate the life force.

The result is the homeopathy practices of like cures like and extreme dilutions. Take a substance that causes symptoms in regular doses then dilute it out of existence so that only the “essence” remains, and use that to cure the same symptoms. After 200 years, these principles are still magic and superstition. They are pre-scientific, and have not been validated by any subsequent scientific research.
Despite this utter lack of scientific plausibility, there have been a number of clinical trials using homeopathy. Most use poor research quality, but some are well controlled. The entirely unsurprising result of this research, when viewed in total, is that homeopathy does not work. Even after two centuries, homeopathy has not been shown to work for a single indication.

The Debate

Despite the complete lack of scientific plausibility and the negative clinical trials, homeopathy is still a multi-billion dollar industry and enjoys approval by most governments. In the US homeopathic potions are classified as drugs and given automatic approval, although the FDA is reviewing that policy.

Because of this, Mark Loeb argues, it is helpful to conduct high quality research into homeopathy. Even if this research does not convince the true believers, the results, assuming they are negative, can be used to pressure governments to more appropriately regulate homeopathy.

Loeb argues that on this specific question, that of nosodes, there has not been any high quality research. He intends to compare nosodes to vaccines to placebos, looking at the production of antibodies and B and T-cell responses. His hypothesis is that nosodes will be no different than placebo.

Caulfield takes the position closer to what David and I took in our article. If 200 years of science is not enough to convince someone that homeopathy is bunk, or to convince regulators, then one more study is not going to do it.

There are also a number of very real downsides to conducting such research. First, the very fact that homeopathy is being researched by a respected researcher at a university will be used by believers to argue that homeopathy is legitimate. Why else would they be studying it? At the very least, it’s an open question.

Second, this is a waste of limited research resources. We know the answer. Both sides agree on what the answer is overwhelmingly likely to be. The time, money, and infrastructure would be better used studying valid scientific questions.

There is also the question of ethics. It is actually unethical to subject people to treatments that the researcher knows to be worthless. There is the principle of equipoise – there has to be a legitimate scientific question at stake. As David and I pointed out in our published article:

Even so, the major assumption underlying EBM is that by the time an investigational treatment is ready for RCTs it has passed all preclinical tests and has thus demonstrated biological plausibility. Before, CAM or IM, treatments without biological plausibility and compelling evidence from preclinical studies and pilot clinical trials usually did not reach the stage of RCTs. Indeed, so integral to this process is biological plausibility based on preclinical data that the Declaration of Helsinki [8] states, ‘medical research involving human subjects must conform to generally accepted scientific principles, be based on a thorough knowledge of the scientific literature, other relevant sources of information, and adequate laboratory and, as appropriate, animal experimentation’.

This gets to the difference between evidence-based medicine and science-based medicine. Loeb is taking an EBM approach here, thinking that clinical evidence will settle this debate. However, SBM differs in that it explicitly holds that clinical trials are only meaningful if they are done in the context of supporting basic science. This is partly because clinical trials are difficult and are rife with false positives. The only way to know where to set the threshold for how much clinical evidence is convincing is to know what the prior probability is from basic science and existing clinical research.

In the case of homeopathy, the prior probability is effectively zero. Therefore, taking a Bayesian approach, one even very rigorous clinical trial cannot possibly change the prior plausibility to any significant degree.

History also suggests the study will not convince anyone of anything. Believers in homeopathy will simply argue that nosodes work through another mechanism not captured by measuring antibodies and white cells. That is a reductionist approach, when homeopathy is holistic and works in a much more subtle way through life essence, or some similar complete nonsense.

The hope that one more study is going to push us over some threshold and now regulators are going to start doing the right thing is not impossible, but is wishful thinking.

One could argue, as a compromise, to do the study in rats. At least then we won’t have the ethical issue of subjecting human subjects to a treatment known to be worthless.

The Real Problem

The real underlying problem that is creating this dilemma is the tolerance for pseudoscience in medicine. I understand Loeb’s intent, and it seems like a rational thing to do. Just do high quality research and use the results to convince everyone, or at least government officials, to do the rational thing. If only the world worked that way.

As Jonathan Swift said: “Reasoning will never make a Man correct an ill Opinion, which by Reasoning he never acquired.”

The truth is a bit more complicated, and there are always exceptions, but recent psychological research shows this to be essentially correct. If you hold a belief for ideological reasons, and you are emotionally invested in that belief, then evidence and reason will not dissuade you. Rather, you will dig in your heels when confronted with evidence.

However, not everyone has an emotionally-invested opinion about homeopathy or alternative medicine. For those without a strong conviction, evidence and reason do matter. So you might argue that doing a study might help convince the uncommitted.

But again – I would argue that we already have enough evidence. Loeb’s position would be semi-legitimate if there were no quality studies of homeopathy. We are simply way past that point – there is overwhelming scientific evidence that homeopathy cannot work and does not work, and any further evidence is redundant. Homeopathy is not an implausible unknown, it is a known failure.

What we really need, as Caulfield points out, is for the scientific, academic, and medical communities to get their shit together. There is a strong consensus that homeopathy is nonsense, the problem is that most academics don’t care. They are shruggies. They think it is harmless nonsense not worth their time or attention. They have either not bothered to look into it enough to know what nonsense it is, or they don’t want to dirty their hands by pointing out that it’s nonsense.

This is a cultural problem within academia. They are collectively failing society. Loeb is not going to fix this underlying problem with one high quality study.

Another way to look at the situation is this – further studies should only be conducted when they are explicitly and directly connected to regulatory action. In other words, do the research if the results of that research will be used to modify regulation. We need more than the hope that it will – we need a commitment ahead of time. Otherwise the research is truly pointless.

Researching the Magic of Homeopathy Steven Novella

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