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article imageHomoeopathy gets an Evidence Check in Britain (Part 1)

By Bart B. Van Bockstaele     Mar 20, 2010 in Health
The British House of Commons Science and Technology Committee (STC) has released its "Evidence Check" report of homoeopathy. The report uses current evidence to support the unequivocal advice to stop government funding of homoeopathy.
The Science and Technology Committee was formed in October 2009. They have started an innovative work programme called "Evidence Check" to examine how the government uses evidence to formulate and review its policies. The committee focusses on two questions:
1 What is the policy?
2 On what evidence is the policy based?
"Evidence Check 2: Homeopathy" is the second report of the committee, hence the '2' in the title. Work on the report was started when it became clear in September 2009 that the government's homoeopathy policy was not based on scientific evidence.
In October 2009, the committee called for written evidence on three subjects:
1 Government policy on licensing of homoeopathic products
2 Government policy on the funding of homoeopathy through the NHS
3 The evidence for homoeopathic products and services
The authors of the 275-page report state that it is not an inquiry into homoeopathy per se. The evidence for homoeopathy is nevertheless examined, because this must be part of the evidence the government uses to create and review its policies.
The report contains two main chapters. Chapter 2 looks at the evidence for providing homoeopathy through the NHS. Chapter 3 addresses the evidence for the licensing scheme of the MHRA for homoeopathic products. This article looks at Chapter 2 and its conclusions. Another article will look at Chapter 3.
Chapter 2 starts by briefly mentioning what homoeopathy is:
Homeopathy is a 200-year old system of medicine that seeks to treat patients with highly diluted substances that are administered orally. Homeopathy is based on two principles:
“like-cures-like” whereby a substance that causes a symptom is used in diluted form to treat the same symptom in illness and “ultra-dilution” whereby the more dilute a substance the more potent it is (this is aided by a specific method of shaking the solutions, termed “succussion”). It is claimed that homeopathy works by stimulating the body’s selfhealing mechanisms.
This is essentially correct, except maybe that it does not mention the patient-homoeopath contact, something that Samuel Hahnemann, the man who dreamed up homoeopathy, considered very important, and with him, most homoeopaths. However, the authors do show that they know this is important later in the report.
Many people confuse homoeopathy and herbalism. They are not the same, and the authors of the report are aware of the confusion:
Homeopathic products should not be confused with herbal remedies. Some homeopathic products are derived from herbal active ingredients, but the important distinction is that homeopathic products are extremely diluted and administered according to specific principles.
Although it is assumed that the amounts of money spent on homoeopathy are very small in comparison to the total budget of the NHS, there are no official figures and the committee advises the government to find out more and to publish the figures.
The report then goes on to look at what should be expected of the evidence upon which the funding of homoeopathy should be based. It starts by quoting part of the NHS constitution, which outlines patients' rights:
You have the right to expect local decisions on funding of [...] drugs and treatments to be made rationally following a proper consideration of the evidence.
The authors agree with this and add that they would expect funding of homoeopathy to be evidence-based. What is the evidence they expect?
Scientific plausibility: We should expect a plausible explanation of how a treatment works, while keeping in mind that it is more important to know whether a treatment works than how it works.
Evidence of efficacy: Should be provided by well-designed and rigorous randomised controlled trials or RCTs. Many RCTs use only small numbers of participants, and this leads to highly variable, even contradictory results. In cases like this, people on both sides of an argument can cherry-pick the data to support their argument. This can be avoided by doing meta-analyses.
A meta-analysis combines the data of several trials into one analysis. If the trials included in the analysis are of high quality, this has the effect of increasing the sample size and the statistical power (reliability). Such meta-analyses can reveal statistical trends that are not apparent in the original trials.
Systematic reviews can also produce interesting evidence.
The committee expects the conclusions on the evidence for the efficacy of homoeopathy to give particular weight to properly conducted meta-analyses and systematic reviews of RCTs.
The report makes a distinction between efficacy and effectiveness and links these to the placebo/nocebo effect.
The authors show that a non-efficacious medicine may sometimes be effective (the patient feels better) because of the placebo effect. This is why the authors put more weight on evidence of efficacy than on evidence of effectiveness. They also expect the government to have a proper understanding of the placebo effect and the ethical issues surrounding it.
This subject is related to the issue of patient satisfaction and whether this should be considered as evidence. They quote the 1999-2000 House of Lords Science and Technology Committee report on complementary and alternative medicines and conclude that patient satisfaction does not help to distinguish between efficacious and placebo treatments.
Homoeopathic provings are not considered evidence of efficacy, not even by homoeopaths.
The authors conclude this section stating that:
We would expect the Government to have a view on the efficacy of homeopathy so as to inform its policy on the NHS funding and provision of homeopathy. Such a view should be based on the best available evidence, that is, rigorous randomised controlled trials and meta-analyses and systematic reviews of RCTs. If the effects of homeopathy can be primarily attributed to the placebo effect, we would expect the Government to have a view on the ethics of prescribing placebos.
Evidence check
The report then goes on to check the evidence for homoeopathy, and they start by looking at the scientific plausibility of homoeopathy and its principles.
The authors take note of the fact that both critics and supporters of homoeopathy doubt the scientific plausibility of any direct physiological mode of action. They quote the Royal Pharmaceutical Society of Great Britain (RPSGB), a firm critic, as saying that "no plausible scientific reason has yet been proposed as to why it should work".
The Prince's Foundation for Integrated Health, a strong advocate for alternology, is quoted as saying that "any specific mechanism of action based on extreme dilution is implausible and regarded as unsupportable by the majority of scientists working in this field".
First, they examine homoeopathy's like-cures-like principle. Among other arguments, they cite Dr Peter Fisher's position on hormesis and show that this is not good evidence for this principle. They conclude that the like-cures-like principle is theoretically weak and that it fails to provide a credible physiological mode of action for homoeopathic products.
Where the principles of ultra-dilutions commonly used in homoeopathy are concerned, they take note of Peter Fisher's description and his emphasis on the importance of succussion, even though he admits that it is not really known how much succussion should be done.
The authors also note that a number of theories have been proposed to explain how water that does not contain a single molecule of an active ingredient would still somehow have an effect in a patient and they note that the unlikely "molecular memory" is the most frequently mentioned. The authors conclude:
We consider the notion that ultra-dilutions can maintain an imprint of substances previously dissolved in them to be scientifically implausible.
Disappointing as the lack of scientific plausibility may be, this does not necessarily mean that homoeopathy does not work. Therefore, the committee looked at the available evidence of efficacy. They note that opinions are conflicting.
On the one hand, the British Homeopathic Association (BHA) is quoted as claiming that four out of five comprehensive reviews of RCTs in homoeopathy have reached the qualified conclusion that homoeopathy differs from placebo.
On the other hand, Professor Edzard Ernst, a former homoeopath himself and Director of the Complementary Medicine Group at the Peninsula Medical School is quoted as disputing this evidence in detail. He also comes close to accusing the BHA of willfully ommitting negative systematic reviews and meta-analyses.
The authors conclude that the systematic reviews and meta-analyses conclusively demonstrate that homoeopathic products perform no better than placebos and they asked the Minister of Health, Mike O'Brien, if the government had any credible evidence that homoeopathy works better than placebos and he responded: "the straight answer is no".
The Committee also regrets that advocates of homoeopathy are selecting the evidence in such a way that they risk confusing or misleading the public, the media and the policy-makers by relying on and promulgating cherry-picking the evidence, and that they did this even in their submissions to the inquiry.
While Robert Wilson, the Chairman of the British Association of Homeopathic Manufacturers (BAHM) and Dr. Robert Mathie advocated in favour of more research, Professor David Harper, Chief Scientist of the Department of Health, and Dr. Ben Goldacre disagreed.
The Committee concluded that there have been enough tests of homoeopathy and that there is plenty of evidence that it is not efficacious. The Committee thinks that further research is not justified in the face of competing priorities. The members of the Committee also think that it is unethical to enter patients into trials to answer questions that have already been answered.
In light of this information, the Committee concludes that homoeopathy is not supported by evidence of efficacy and is therefore no more than a placebo, albeit a popular one.
This does not mean that homoeopathy may be effective and the Committee looked into that as well. The conclusion is that they do not doubt that homoeopathy makes some patients feel better. However, this can be achieved through the placebo effect alone and it is therefore not proof that homoeopathy is efficacious.
The Committee did not think that it was possible to determine the cost-effectiveness of homoeopathy on a national level because the cost has not been determined. It does, however, mention such a study on a local level that has concluded that funding homoeopathy was not cost-effective in light of competing priorities, regardless of whether it works or not.
The next two sections of the report are intimately related. The authors note that the lack of evidence is preventing NICE from evaluating homoeopathy while it is not preventing the NHS from spending money on it.
When a doctor prescribes a placebo, he or she must claim that it is an effective therapy. The patient is therefore being deceived and the doctor risks damaging the trust relationship between the doctor and her/his patient.
What about patient choice? In the past, patients had no choice. Medicine was a highly paternalistic system and the doctor simply "knew" what was best. Modern medicine has shied away from this and prefers to give patients options to choose from.
It is precisely this freedom of choice that is often used as an argument to publicly fund homoeopathy. However, this implies that the patient fully understands the implications of her/his choice. In other words, the choice must be an informed one. Professor Ernst is quoted as saying that patient choice that is not guided by evidence is not choice but arbitrariness.
The RPSGB has the same view and says that it is essential that the patient is given the appropriate information to make these informed choices and as a consequence it should be clear to the patient that there is no scientific evidence for homoeopathy.
The Committee concludes that for the patient to have a real choice, he/she must be informed that homoeopathy is a placebo. Without it, patient choice is meaningless and with it, the placebo effect of homoeopathy may be diminished. The authors say that providing homoeopathy on the NHS, in effect, diminishes, not increases informed patient choice.
The report also touches on the safety of homoeopathy or, as it is called, the risk of harm to patients. It is pointed out that homoeopathic treatment may seem harmless enough, but that patients whose symptoms improve after treatment, because of the placebo effect or because the symptoms would improve without treatment, may delay seeking a proper medical diagnosis and proper medical care. The result can be harm or, in serious cases, death, as the report shows.
One problem medical practitioners are facing is that homoeopathic products are provided through the NHS. This may lead patients to reasonably conclude that homoeopathy is an evidence-based treatment.
The authors note that the government's position regarding homoeopathy is confused: even though the government accepts the evidence-based view that homoeopathy is a placebo, it does pay for homoeopathy on the NHS without having a view on the ethics of prescribing placebos.
The report concludes that placebos should not be routinely prescribed on the NHS, that homoeopathy is a placebo and that the government should stop allowing the funding of homoeopathy on the NHS. It also concludes that the funding of homoeopathic hospitals should stop and that NHS doctors should not refer patients to homoeopaths.
More about Evidence check, Homeopathy, Evidence science, House commons
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