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In 1998 the Annual Representative Meeting of the British Medical Association passed a Resolution requesting the Board of Science and Education to look into the scientific basis and efficacy of acupuncture and the quality of training and competence of its practitioners. The Board’s

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report appeared in 2000 and was broadly sympathetic to acupuncture; more so than two earlier reports published in 1986 and 1993. The report accepted that acupuncture seems to be useful for back and neck pain, osteoarthritis, headache, and nausea and vomiting. It found that acupuncture was ineffective for smoking cessation, weight loss, tinnitus, and asthma. It also made the important point that scientific evidence of effectiveness is not necessarily the same as cost-effectiveness; even if the value of a treatment can be partially or wholly ascribed to the placebo effect, it may still be useful in clinical practice and should not be ignored on that ground alone. However, the dangers of acupuncture were also pointed out in the report and this led to a number of recommendations about training.

The BMA report made the usual plea for more research. This is in danger of becoming a ritual incantation in such documents, but it does signal a real and serious lack. Medicine these days is expected to be ‘evidence-based’, and it has to be admitted that the evidence base for acupuncture is still fairly weak. There is a large amount of Chinese research material but this commands little respect in the West (Hayhoe, 1998). Even when it is available in translation, the norms of research that apply in China for traditional medicine are mostly very different from those prevailing in the West. Hardly any trials are randomized controlled trials. Most claim success rates that strike Western acu- puncturists as improbably large – 100 per cent in many cases – and a recent review found no trial with a reported success rate lower than 87.5 per cent. Such claims excite scepticism in Western readers, but they really reflect a different way of describing the results, which tends to exaggerate the benefits. If lesser degrees of benefit are excluded, and only ‘cure’ or ‘marked improvement’ are accepted as indicating success, the response rate reduces to about 70 per cent, which is more reasonable. Most Chinese research in acupuncture is never translated, and even those articles that do appear in the West contain mistransla- tions of medical terms. For all these reasons, the Chinese literature is unlikely to have much impact on Western medical opinion in the foreseeable future.

Research in the West isn’t without its problems either (Lewith & Vincent, 1998). Hitherto, many who have published papers on acu- puncture have been inexperienced in research techniques. They have been working alone or in small hospital centres, with inadequate patient numbers, difficulty in finding suitable controls, and no statistical advice. University departments don’t always show much interest in acupuncture research, and even when they do, the academics don’t always know a great deal about acupuncture.

A recurrent difficulty attends the question of choosing a suitable control procedure. To the mildly interested onlooker with no particular interest in acupuncture it might seem that it would be enough to compare ‘real’ acupuncture with needling at non-acupuncture points,

and a number of trials have used this method, which they call sham acupuncture. This approach is, at best, only suitable for the investiga- tion of traditional acupuncture; it won’t work for acupuncture which neglects or radically reinterprets the concept of ‘points’. Fortunately, more researchers are now beginning to realize that ‘sham’ acupuncture is not equivalent to an inert placebo. An attempt has now been made, by Park and coworkers (1999) at the University of Exeter, to design a sham needle which doesn’t pierce the skin but produces a sensation that patients would think was due to acupuncture. Evaluation of this instrument is now going on, and if it is successful it will be an advance, though it may not be without problems of its own. In view of such difficulties many researchers have concluded that placebo acupuncture is not a real possibility, and that a better idea is to compare acupuncture with other kinds of treatment.

Two fairly comprehensive reviews of acupuncture research appeared in the 1980s. Lewith and Machin (1983) reviewed 32 papers and concluded that the response rate is about 30 per cent for placebo, 50 per cent for ‘sham’ acupuncture, and 70 per cent for ‘real’ acupuncture. Most of the published trials, they believe, would not be capable of detecting differences of this order, hence one cannot necessarily conclude from these trials that acupuncture is merely a placebo treatment. They suggest that instead of comparing acupuncture and placebo it would be better to analyse the time for which a patient obtains relief from a given treatment.

Vincent and Richardson (1986) reviewed 40 studies. They, too, found serious shortcomings in most of them, but they concluded that there is good evidence for the short-term effectiveness of acupuncture in relieving a number of kinds of pain (mainly headache and backache but also some other painful disorders). They found the short-term response rate to be 50–80 per cent – higher, that is, than the expected placebo response rate of 30–35 per cent. The good initial response was not so well maintained, however, unless patients received booster treatments at intervals; this, of course, accords with what is found in ordinary clinical practice. No conclusions could be drawn about whether certain points are more effective than others.

Like Lewith and Machin, Vincent and Richardson were sceptical about the value of double-blind trials in acupuncture. They argued that single- blind trials are adequate ‘provided efforts are made to monitor independently the impact of nonspecific effects and/or ensure that they do not vary between groups’. They also made a plea, which I would certainly endorse, for authors of research papers to give as much information as possible about what they actually did (number of sessions, duration and frequency of stimulation, whether de qi was sought, method of point selection and so forth).

In spite of the difficulties that attend the carrying out of good research in acupuncture, it’s very important that it be done. Acupuncture has come

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and gone more than once in the West in the last couple of centuries, and there is no guarantee that it will not fall into disuse yet again. That would be a pity, for it has a valuable, if limited, contribution to make to medicine. At present it is more than half-way across the gulf that separates charlatanry from science in the minds of doctors, but if it is to complete the transition medical acupuncturists will have to produce evidence that it works.

An important review by Ezzo and colleagues (2000) was concerned with evidence for the effectiveness of acupuncture in the treatment of chronic pain. These authors had four aims: to summarize the effectiveness of acupuncture for chronic pain according to the type of control group; to see whether low-quality acupuncture trials are associated with positive outcomes; to see which features of the treatment are associated with positive results; and to identify areas of future research. Reports of trials in English were reviewed. They were included if they were randomized, had a comparison group, had a study population with pain longer than 3 months, used needles, and had a measurement of pain relief.

In all, 51 trials representing 2423 chronic pain patients were reviewed. Overall, 21 were positive, 3 negative, and 27 neutral. Most were small. Two-thirds were classed as low quality, and there was a significant trend for low quality to be associated with positive outcome. Trials in which equal therapeutic time was not spent with control and experimental groups tended to be positive. All these findings, of course, support the view of critics who dismiss acupuncture as ineffective.

Four types of control groups were used: waiting list, inert controls (sham TENS, sugar pills, placebo acupuncture), sham acupuncture, and active control (TENS). There was limited evidence that acupuncture is better than no treatment (waiting list); the evidence for the other kinds of control was inconclusive.

For me the most interesting finding was that so-called sham acupuncture was as effective as ‘real’ acupuncture but both were more effective than inert placebo. This, the authors say, suggests that so-called sham acupuncture may not be a true placebo but may have analgesic effects of its own. On the view of acupuncture that I have been advocating in this book, this finding is, of course, exactly what would be predicted; I don’t believe that there is such a thing as sham acupuncture, but only more effective versus less effective needling.

An interesting finding is that six or more treatments were significantly associated with positive outcome even when the quality of the trials was taken into account. This suggests that repeated acupuncture has a cumulative effect, although other interpretations (chance, or patient ‘investment’ in the outcome) may also explain it. However, my own experience, which is in line with that of many others, is that the maximum effect may be achieved in considerably fewer than six treatments at times, so there should be no question of stipulating this number as an irreducible minimum; each patient needs to be assessed individually.