Trick or Treatment by Simon Singh, Edzard Ernst M.D. Page A
Authors: Simon Singh, Edzard Ernst M.D.
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Blinding doctors so that they are unaware whether they are giving a real or a placebo treatment to each patient.
A trial that includes all these features is known as a randomized, placebo-controlled, double-blind clinical trial, and it is considered to be the highest possible standard of medical testing. Nowadays, the various national bodies responsible for authorizing new treatments will usually make their decisions based on the results obtained from such studies.
Sometimes, however, it is necessary to conduct trials that are closely related to this format, but which do not involve a placebo. For example, imagine that scientists want to test a new drug for a condition that is already treated with a partly effective existing drug. Point 3 indicates that the control group receives only a placebo, but this would be unethical if it deprived patients of the partly effective drug. In this situation, the control group would receive the existing drug and the outcome would be compared against the other group receiving the new drug – the trial would not be placebo-controlled, but there would still be a control, namely the existing drug. Such a trial should still adhere to all the other requirements, such as randomization and double-blinding.
These sorts of clinical trials are invaluable when conducting medical research. Although the results from other types of trial and other evidence might be considered, they are generally deemed to be less convincing when it comes to the key question: is a treatment effective for a particular condition?
Returning to acupuncture, we can re-examine the clinical trials of the 1970s and 1980s – were these trials of high quality and were they properly blinded, or is it possible that the reported benefits of acupuncture were due merely to the placebo effect?
A good example of the type of acupuncture trial that took place during this period was one conducted in 1982 by Dr Richard Coan and his team, who wanted to examine whether or not acupuncture was effective for neck pain. His treatment group consisted of fifteen patients who received acupuncture, while his control group consisted of another fifteen patients who remained on a waiting list. The results would have seemed unequivocal to fans of acupuncture, because 80 per cent of patients in the acupuncture group reported an improvement, compared to only 13 per cent of the control group. The extent of the pain relief in the acupuncture group was so great that they halved their intake of painkillers, whereas the control group reduced their intake of pills by only one tenth.
Comparing the acupuncture group against the control group shows that the improvement due to acupuncture is much greater than can be explained by any natural recovery. However, was the benefit from acupuncture due to psychological or physiological factors or a mix of the two? Did the acupuncture trigger a genuine healing mechanism, or did it merely stimulate a placebo response? The latter possibility has to be treated seriously, because acupuncture has many of the attributes that would make it an ideal placebo treatment: needles, mild pain, the slightly invasive nature, exoticism, a basis in ancient wisdom and fantastic press coverage.
So Dr Coan’s clinical trial, along with many of the others conducted in the 1970s and 1980s, suffered from the problem that they could not determine whether acupuncture was offering a real benefit or merely a placebo benefit. The ideal way to find out whether acupuncture was genuinely effective would have been to give a placebo to the control group, something that seemed identical to acupuncture but which was totally inert. Unfortunately, finding such a placebo proved difficult – how can you create a therapy that appears to be acupuncture but which is not actually acupuncture? How do you blind patients to whether or not they are receiving acupuncture?
Placebo control groups are easy to arrange in the context of conventional drug
Blinding doctors so that they are unaware whether they are giving a real or a placebo treatment to each patient.
A trial that includes all these features is known as a randomized, placebo-controlled, double-blind clinical trial, and it is considered to be the highest possible standard of medical testing. Nowadays, the various national bodies responsible for authorizing new treatments will usually make their decisions based on the results obtained from such studies.
Sometimes, however, it is necessary to conduct trials that are closely related to this format, but which do not involve a placebo. For example, imagine that scientists want to test a new drug for a condition that is already treated with a partly effective existing drug. Point 3 indicates that the control group receives only a placebo, but this would be unethical if it deprived patients of the partly effective drug. In this situation, the control group would receive the existing drug and the outcome would be compared against the other group receiving the new drug – the trial would not be placebo-controlled, but there would still be a control, namely the existing drug. Such a trial should still adhere to all the other requirements, such as randomization and double-blinding.
These sorts of clinical trials are invaluable when conducting medical research. Although the results from other types of trial and other evidence might be considered, they are generally deemed to be less convincing when it comes to the key question: is a treatment effective for a particular condition?
Returning to acupuncture, we can re-examine the clinical trials of the 1970s and 1980s – were these trials of high quality and were they properly blinded, or is it possible that the reported benefits of acupuncture were due merely to the placebo effect?
A good example of the type of acupuncture trial that took place during this period was one conducted in 1982 by Dr Richard Coan and his team, who wanted to examine whether or not acupuncture was effective for neck pain. His treatment group consisted of fifteen patients who received acupuncture, while his control group consisted of another fifteen patients who remained on a waiting list. The results would have seemed unequivocal to fans of acupuncture, because 80 per cent of patients in the acupuncture group reported an improvement, compared to only 13 per cent of the control group. The extent of the pain relief in the acupuncture group was so great that they halved their intake of painkillers, whereas the control group reduced their intake of pills by only one tenth.
Comparing the acupuncture group against the control group shows that the improvement due to acupuncture is much greater than can be explained by any natural recovery. However, was the benefit from acupuncture due to psychological or physiological factors or a mix of the two? Did the acupuncture trigger a genuine healing mechanism, or did it merely stimulate a placebo response? The latter possibility has to be treated seriously, because acupuncture has many of the attributes that would make it an ideal placebo treatment: needles, mild pain, the slightly invasive nature, exoticism, a basis in ancient wisdom and fantastic press coverage.
So Dr Coan’s clinical trial, along with many of the others conducted in the 1970s and 1980s, suffered from the problem that they could not determine whether acupuncture was offering a real benefit or merely a placebo benefit. The ideal way to find out whether acupuncture was genuinely effective would have been to give a placebo to the control group, something that seemed identical to acupuncture but which was totally inert. Unfortunately, finding such a placebo proved difficult – how can you create a therapy that appears to be acupuncture but which is not actually acupuncture? How do you blind patients to whether or not they are receiving acupuncture?
Placebo control groups are easy to arrange in the context of conventional drug
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