As I write these words, I am travelling back from a medical conference. The organisers had invited me to give a lecture which I concluded saying: “anyone in medicine not believing in evidence-based health care is in the wrong business”. This statement was meant to stimulate the discussion and provoke the audience who were perhaps just a little on the side of those who are not all that taken by science.
I may well have been right, because, in the coffee break, several doctors disputed my point; to paraphrase their arguments: “You don’t believe in the value of experience, you think that science is the way to know everything. But you are wrong! Philosophers and other people, who are a lot cleverer than you, tell us that science is not the way to real knowledge; and in some forms of medicine we have a wealth of experience which we cannot ignore. This is at least as important as scientific knowledge. Take TCM, for instance, thousands of years of tradition must mean something; in fact it tells us more than science will ever be able to. Qi-energy, for instance, is a concept based on experience, and science is useless at verifying it.”
I disagreed, of course. But I am afraid that I did not convince my colleagues. The appeal to tradition is amazingly powerful, so much so that even well-seasoned physicians fall for it. Yet it nevertheless is a fallacy, I am sure.
So what does experience tell us, how is it generated and why should it be unreliable?
On the level of the individual, experience emerges when a clinician makes similar observations several times in a row. This is so persuasive that few doctors are immune to the phenomenon. Let’s assume the experience is about acupuncture, more precisely about acupuncture for smoking cessation. The acupuncturist presumably has learnt during his training that his therapy works for that indication via stimulating the flow of Qi, and promptly tries it on several patients. Some of them come back for more and report that they find it easier to give up cigarettes after consulting him. This happens repeatedly, and our clinician forthwith is convinced – in fact, he knows – that acupuncture is effective for smoking cessation.
If we critically analyse this scenario, what does it tell us? It tells us very little of relevance, I am afraid. The scenario is entirely compatible with a whole host of explanations which have nothing to do with the effects of acupuncture per se:
- Those patients who did not manage to stop smoking might not have returned. Only seeing his successes without his failures, the acupuncturist would have got the wrong end of the stick.
- Human memory is selective such that the few patients who did come back and reported failure might easily get forgotten by the clinician. We all remember the good things and forget the disappointments, particularly if we are clinicians.
- The placebo-effect might have played a dirty trick on the experience of our acupuncturist.
- Some patients might have used nicotine patches that helped him to stop smoking without disclosing this fact to the acupuncturist who then, of course, attributed the benefit to his needling.
- The acupuncturist – being a very kind and empathetic clinician – might have involuntarily induced some of his patients to show kindness in return and thus tell porkies about their smoking habits which would have created a false positive impression about the effectiveness of his treatment.
- Being so empathetic, the acupuncturists would have provided lots of encouragement to stop smoking which, in some patients, might have been sufficient to kick the habit.
The long and short of all this is that our acupuncturist gradually got convinced by this interplay of factors that Qi exists and that acupuncture is an ineffective treatment. Hence forth he would bet his last shirt that he is right about this – after all, he has seen it with his own eyes, not just once but many times. And he will doubt anyone who shows him evidence that says otherwise. In fact, he is likely become very sceptical about scientific evidence in general – just like the doctors who talked to me after my lecture.
On a population level, such experience will be prevalent in not just one but most acupuncturists. Our clinician’s experience is certainly not unique; others will have made it too. In fact, as an acupuncturist, it is hard not to make it. Acupuncturists would have told everyone else about it, perhaps reported it on conferences or published it in articles or books. Experience of this nature is passed on from generation to generation, and soon someone will be able to demonstrate that acupuncture has been used ’effectively’ for smoking cessation since decades or centuries. The creation of a myth out of unreliable experience is thus complete.
Am I saying that experience of this nature is always and necessarily wrong or useless? No, I am not. It can be and often is correct. But, at the same time, it is frequently incorrect. It can serve as a valuable indicator but not more. Experience is not a tool for reliably informing us about the effectiveness of medical interventions. Experience based-medicine is an obsolete pseudo-medicine burdened with concepts that are counter-productive to optimal health care.
Philosophers and other people who are much cleverer than I am have been trying for some time to separate good from bad science and evidence from experience. Most recently, two philosophers, MASSIMO PIGLIUCCI and MAARTEN BOUDRY, commented specifically on this problem in relation to TCM. I leave you with some extensive quotes from what they wrote.
… pointing out that some traditional Chinese remedies (like drinking fresh turtle blood to alleviate cold symptoms) may in fact work, and therefore should not be dismissed as pseudoscience… risks confusing the possible effectiveness of folk remedies with the arbitrary theoretical-metaphysical baggage attached to it. There is no question that some folk remedies do work. The active ingredient of aspirin, for example, is derived from willow bark…
… claims about the existence of “Qi” energy, channeled through the human body by way of “meridians,” though, is a different matter. This sounds scientific, because it uses arcane jargon that gives the impression of articulating explanatory principles. But there is no way to test the existence of Qi and associated meridians, or to establish a viable research program based on those concepts, for the simple reason that talk of Qi and meridians only looks substantive, but it isn’t even in the ballpark of an empirically verifiable theory.
…the notion of Qi only mimics scientific notions such as enzyme actions on lipid compounds. This is a standard modus operandi of pseudoscience: it adopts the external trappings of science, but without the substance.
…The notion of Qi, again, is not really a theory in any meaningful sense of the word. It is just an evocative word to label a mysterious force of which we do not know and we are not told how to find out anything at all.
Still, one may reasonably object, what’s the harm in believing in Qi and related notions, if in fact the proposed remedies seem to help? Well, setting aside the obvious objections that the slaughtering of turtles might raise on ethical grounds, there are several issues to consider. To begin with, we can incorporate whatever serendipitous discoveries from folk medicine into modern scientific practice, as in the case of the willow bark turned aspirin. In this sense, there is no such thing as “alternative” medicine, there’s only stuff that works and stuff that doesn’t.
Second, if we are positing Qi and similar concepts, we are attempting to provide explanations for why some things work and others don’t. If these explanations are wrong, or unfounded as in the case of vacuous concepts like Qi, then we ought to correct or abandon them. Most importantly, pseudo-medical treatments often do not work, or are even positively harmful. If you take folk herbal “remedies,” for instance, while your body is fighting a serious infection, you may suffer severe, even fatal, consequences.
…Indulging in a bit of pseudoscience in some instances may be relatively innocuous, but the problem is that doing so lowers your defenses against more dangerous delusions that are based on similar confusions and fallacies. For instance, you may expose yourself and your loved ones to harm because your pseudoscientific proclivities lead you to accept notions that have been scientifically disproved, like the increasingly (and worryingly) popular idea that vaccines cause autism.
Philosophers nowadays recognize that there is no sharp line dividing sense from nonsense, and moreover that doctrines starting out in one camp may over time evolve into the other. For example, alchemy was a (somewhat) legitimate science in the times of Newton and Boyle, but it is now firmly pseudoscientific (movements in the opposite direction, from full-blown pseudoscience to genuine science, are notably rare)….
The borderlines between genuine science and pseudoscience may be fuzzy, but this should be even more of a call for careful distinctions, based on systematic facts and sound reasoning. To try a modicum of turtle blood here and a little aspirin there is not the hallmark of wisdom and even-mindedness. It is a dangerous gateway to superstition and irrationality
Realgar, a commonly used traditional Chinese medicine, has – according to the teachings of Traditional Chinese Medicine (TCM) – acrid, bitter, warm, and toxic characteristics and is affiliated with the Heart, Liver and Stomach meridians. It is used internally against intestinal parasites and treat sore throats, and is applied externally to treat swelling, abscesses, itching, rashes, and other skin disorders.
Chemically, it is nothing other than arsenic sulphide. Despite its very well-known toxicity, is thought by TCM-practitioners to be safe, and it has been used in TCM under the name ‘Xiong Huang’ for many centuries. TCM-practitioners advise that the typical internal dose of realgar is between 0.2 and 0.4 grams, decocted in water and taken up to two times per day. Some practitioners may recommend slightly higher doses (0.3-0.9 grams). Larger doses of realgar may be used if it is being applied topically.
Toxicologists from Taiwan report a case of fatal realgar poisoning after short-term use of a topical realgar-containing herbal medicine.
A 24-year-old man with atopic dermatitis had received 18 days of oral herbal medicine and realgar-containing herbal ointments over whole body from a TCM-practitioner. Seven days later, he started to develop loss of appetite, dizziness, abdominal discomfort, an itching rash and skin scaling. Subsequently he suffered generalized oedema, nausea, vomiting, decreased urine amount, diarrhoea, vesico-oedematous exanthemas, malodorous perspiration, fever, and shortness of breath.
He was taken to hospital on day 19 when the dyspnoea became worse. Toxic epidermal necrolysis complicated with soft tissue infection and sepsis were then diagnosed. The patient died shortly afterwards of septic shock and multiple organ failure. Post-mortem blood arsenic levels were elevated at 1225 μg/L. The analysis of the patient’s herbal remedies yielded a very high concentration of arsenic in three unlabelled realgar-containing ointments (45427, 5512, and 4229 ppm).
The authors of this report concluded that realgar-containing herbal remedy may cause severe cutaneous adverse reactions. The arsenic in realgar can be absorbed systemically from repeated application to non-intact skin and thus should not be extensively used on compromised skin.
The notion that a treatment that ‘has stood the test of time’ must be safe and effective is very wide-spread in alternative medicine. This, we often hear, applies particularly to the external use of traditional remedies – what can be wrong with putting a traditional Chinese herbal cream on the skin?? This case, like so many others, should teach us that this appeal to tradition is a classical and often dangerous fallacy. And the ‘realgar-story’ also suggests that, in TCM, the ‘learning-curve’ is very flat indeed.
Chinese and Ayurvedic remedies are often contaminated with toxic heavy metals. But the bigger danger seems to be that some of these traditional ‘medicines’ contain such toxins because, according to ‘traditional wisdom’, these constituents have curative powers. I think that, until we have compelling evidence that any of these treatments do more good than harm, we should avoid taking them.
Australian researchers wanted to know whether acupuncture is effective for alleviating the symptoms of fibromyalgia, a common painful condition for which no universally accepted treatment exists. For this purpose, they conducted a Cochrane review. After extensive literature searches, they identified 9 RCTs, extracted their data and assessed risk of bias.
The results show that all studies except one were at low risk of selection bias; five were at risk of selective reporting bias; two were subject to attrition bias (favouring acupuncture); three were subject to performance bias (favouring acupuncture) and one to detection bias (favouring acupuncture).
Three studies utilised electro-acupuncture (EA) and the remainder manual acupuncture (MA) without electrical stimulation.
Low quality evidence from one study (13 participants) showed EA improved symptoms with no adverse events at one month following treatment.
Moderate quality evidence from six studies (286 participants) indicated that acupuncture (EA or MA) was no better than sham acupuncture, except for less stiffness at one month. Subgroup analysis of two studies (104 participants) indicated benefits of EA. Mean pain was 70 points on 0 to 100 point scale with sham treatment; EA reduced pain by 13% (5% to 22%).
Low-quality evidence from one study suggested that MA resulted in poorer physical function: mean function in the sham group was 28 points (100 point scale); treatment worsened function by a mean of 6 points.
Moderate quality evidence from one study (58 participants) found that, compared with standard therapy alone (antidepressants and exercise), adjunct acupuncture therapy reduced pain at one month after treatment.
Low quality evidence from one study (38 participants) showed a short-term benefit of acupuncture over antidepressants in pain relief.
Moderate-quality evidence from one study (41 participants) indicated that deep needling with or without deqi did not differ in pain, fatigue, function or adverse events.
Four studies reported no differences between acupuncture and control or other treatments described at six to seven months follow-up.
No serious adverse events were reported, but there were insufficient adverse events to be certain of the risks.
The authors draw the following conclusions: There is low to moderate-level evidence that compared with no treatment and standard therapy, acupuncture improves pain and stiffness in people with fibromyalgia. There is moderate-level evidence that the effect of acupuncture does not differ from sham acupuncture in reducing pain or fatigue, or improving sleep or global well-being. EA is probably better than MA for pain and stiffness reduction and improvement of global well-being, sleep and fatigue. The effect lasts up to one month, but is not maintained at six months follow-up. MA probably does not improve pain or physical functioning. Acupuncture appears safe. People with fibromyalgia may consider using EA alone or with exercise and medication. The small sample size, scarcity of studies for each comparison, lack of an ideal sham acupuncture weaken the level of evidence and its clinical implications. Larger studies are warranted.
What does all that mean? In my view, it means that there is no sound evidence base for acupuncture as a treatment of fibromyalgia – or as we expressed it in our own systematic review of 2007: The notion that acupuncture is an effective symptomatic treatment for fibromyaligia is not supported by the results from rigorous clinical trials. On the basis of this evidence, acupuncture cannot be recommended for fibromyalgia.
Tai Chi, as we know it in the West, is said to promote the smooth flow of “energy” throughout the body by performing postures, slow meditative movements and controlled breathing. Tai Chi is also supposed to help increasing flexibility, suppleness, balance and coordination. According to enthusiasts, the smooth, gentle movements of Tai Chi aid relaxation and help to keep the mind calm and focused.
Tai Chi has become popular in Western countries and is being considered for a surprisingly wide range of conditions. The patient/consumer is taught to perform postures, slow meditative movements and controlled breathing. The concepts underlying Tai Chi are strange, but that does not necessarily mean that the treatment is not effective for certain illnesses or symptoms.
There has been a surprising amount of research in this area, and some studies have generated encouraging results. A recent study which is unfortunately not available electronically ( Wu, WF; Muheremu, A; Chen, CH; Liu, WG; Sun, L. Effectiveness of Tai Chi Practice for Non-Specific Chronic Low Back Pain on Retired Athletes: A Randomized Controlled Study. JOURNAL OF MUSCULOSKELETAL PAIN 2013, 21:1, p.37-45) tested the effectiveness of Tai Chi for chronic back pain. Specifically, the researchers wanted to determine whether regular Tai Chi practice is superior to other means of sports rehabilitation in relieving non-specific chronic low back pain [LBP] in a younger population. They randomized 320 former athletes suffering from chronic LBP into a treatment [tai chi practice] and several control groups [regular sessions with swimming, backward walking or jogging, or no such interventions]. At the beginning, middle, and end of a six-month intervention, patients from all groups completed questionnaires assessing the intensity of LBP; in addition, a physical examination was conducted.
After 3 and 6 months, no statistically significant difference in the intensity of LBP was demonstrated between the Tai Chi and swimming. However, significant differences were demonstrated between the Tai Chi and backward walking, jogging, and no exercise groups.
The authors’ concluded that “Tai chi has better efficacy than certain other sports on the treatment of non-specific chronic LBP.”
This is only the second RCT of Tai chi for back pain. The first such study consisted of 160 volunteers between ages 18 and 70 years with persistent nonspecific low back pain. The experimental group (n = 80) had 18 Tai Chi sessions over a 10-week period. The waitlist control group continued with their usual health care. Bothersomeness of symptoms was the primary outcome, and secondary outcomes included pain intensity and pain-related disability. Tai Chi reduced bothersomeness of back symptoms by 1.7 points on a 0-10 scale, reduced pain intensity by 1.3 points on a 0-10 scale, and improved self-report disability by 2.6 points on the 0-24 Roland-Morris Disability Questionnaire scale. The authors of this RCT concluded that a 10-week Tai Chi program improved pain and disability outcomes and can be considered a safe and effective intervention for those experiencing long-term low back pain symptoms.
My own team have conducted their fair share of Tai Chi research. Specifically,we have published several systematic reviews of Tai Chi as an adjunctive or supportive treatment of various conditions, and the conclusions (in italics) have been mixed.
DIABETES: The existing evidence does not suggest that tai chi is an effective therapy for type 2 diabetes.
HYPERTENSION: The evidence for tai chi in reducing blood pressure in the elderly individuals is limited.
BREAST CANCER: the existing trial evidence does not show convincingly that tai chi is effective for supportive breast cancer care.
IMPROVEMENT OF AEROBIC EXCERCISE CAPACITY: the existing evidence does not suggest that regular tai chi is an effective way of increasing aerobic capacity.
PARKINSON’S DISEASE: the evidence is insufficient to suggest tai chi is an effective intervention for Parkinson’s Disease.
OSTEOPOROSIS: The evidence for tai chi in the prevention or treatment of osteoporosis is not convincing.
OSTEOARTHRITIS: there is some encouraging evidence suggesting that tai chi may be effective for pain control in patients with knee OA.
RHEUMATOID ARTHRITIS: Collectively this evidence is not convincing enough to suggest that tai chi is an effective treatment for RA.
Finally, an overview over all systematic reviews of Tai Chi suggested that the only area where the evidence is convincing is the prevention of falls in the elderly.
I think, this indicates that we should not pin our hopes too high as to the therapeutic value of Tai Chi. In particular, for back pain, the evidence might be optimistically judged as encouraging, but it is by no means convincing; the effect size seems to be small and two studies are not enough to issue general recommendations. On the other hand, considering that there is so little to offer to back pain patients, I concede that this is an area that should be studied further. Meanwhile, one could argue that Tai Chi can be fun and is devoid of risks – so, why not give it a try?
A stroke is a condition where brain cells get irreversibly damaged either by a haemorrhage in the brain or by a blood clot cutting off oxygen supply. This process leaves most patients with neurological deficits such as difficulties in moving, speaking, concentrating etc. As other parts of the brain learn to take over, these problems can partly or completely resolve themselves over time, but many patients are left with permanent handicaps. Stroke-rehabilitation can minimise these problems, and there is a long-standing debate as to which measures are most effective. Acupuncture has been discussed as a method to improve the results of stroke-rehabilitation, but the evidence is hotly disputed. This is why a new study in this area is an important contribution to our existing knowledge.
The aim of this randomised trial was to test the effectiveness of acupuncture in promoting the recovery of patients with ischaemic stroke and to determine whether the outcomes of combined physiotherapy and acupuncture are superior to those with physiotherapy alone. The Chinese investigators recruited 120 patients who received one of three daily treatments: 1) acupuncture, 2) physiotherapy, 3) physiotherapy combined with acupuncture. Motor function in the limbs was measured with the Fugl-Meyer assessment (FMA); the modified Barthel index (MBI) was used to rate activities of daily living; both of these measures are validated and well-established. All evaluations were performed by assessors blinded to treatment allocation.
At baseline, FMA and MBI scores did not significantly differ among the treatment groups. Compared with baseline, on day 28 of therapy, the mean FMA scores of the physiotherapy, acupuncture, and combined treatment groups had increased by 65.6%, 57.7%, and 67.2%, respectively; on day 56, FMA scores had increased by 88.1%, 64.5%, and 88.6%, respectively. The respective MBI scores in the three groups had increased by 85.2%, 60.4%, and 63.4% at day 28 and by 108.0%, 71.2%, and 86.2% at day 56, respectively. However, FMA scores did not significantly differ between the three treatment groups on the 28th day. By the day 56, the FMA and MBI scores of the physiotherapy group were 46.1% and 33.2% greater, respectively, than those in the acupuncture group. No significant differences were seen between the combined treatment group and the other groups. The FMA subscores for the upper extremities did not show significant improvements in any group on day 56.
The authors draw the following conclusion: “Acupuncture is less effective for the outcome measures studied than is physiotherapy. Moreover, the therapeutic effect of combining acupuncture with physiotherapy was not superior to that of physiotherapy alone. A larger-scale clinical trial is necessary to confirm these finding.”
Our own study arrived at similarly disappointing conclusions: “Acupuncture is not superior to sham treatment for recovery in activities of daily living and health-related quality of life after stroke, although there may be a limited effect on leg function in more severely affected patients“. Our review of all 10 sham-controlled RCTs in this area is also in line with the results of this new study: “Our meta-analyses of data from rigorous randomized sham-controlled trials did not show a positive effect of acupuncture as a treatment for functional recovery after stroke”
I am quite sure that some acupuncture-enthusiasts will dispute this evidence. They might argue that I am too critical, the trials were not done optimally, that acupuncturists have seen plenty of good results in their clinical practice, that acupuncture is a complex intervention that does not fit into the straight jacket of an RCT, that this or that “prestigious” organisation recommends acupuncture for stroke patients, that it would be wrong not to give acupuncture a try etc. etc. I would counter that the reliable evidence available to date is sufficiently conclusive to stop claiming that acupuncture is effective and thus give false hope to severely suffering, vulnerable patients. Moreover, I would advocate using the sparse available resources to help stroke victims with treatments that demonstrably work.
Whenever we consider alternative medicine, we think of therapeutic interventions and tend to forget that alternative practitioners frequently employ diagnostic methods which are alien to mainstream health care. Acupuncturists, iridologists, spiritual healers, massage therapists, reflexologists, applied kinesiologists, homeopaths, chiropractors, osteopaths and many other types of alternative practitioners all have their very own ways of diagnosing what might be wrong with their patients.
The purpose of a diagnostic test or technique is, of course, to establish the presence or absence of an abnormality, condition or disease. Conventional doctors use all sorts of validated diagnostic methods, from physical examination to laboratory tests, from blood pressure measurements to X-rays. Alternative practitioners use mostly alternative methods for arriving at a diagnosis, and we should ask: how reliable are these techniques?
Anyone trying to answer this question, will be surprised to find how very little reliable information on this topic exists. Scientific tests of the validity of alternative diagnostic tests are a bit like gold dust. And this is why a recently published article is, in my view, of particular importance and value.
The aim of this study was to evaluate the inter-rater reliability of pulse-diagnosis as performed by Traditional Korean Medicine (TKM) clinicians. A total 658 patients with stroke who were admitted into Korean oriental medical university hospitals were included. Each patient was seen by two TKM-experts for an examination of the pulse signs – pulse diagnosis is regularly used by practitioners of TKM and Traditional Chinese Medicine (TCM), and is entirely different from what conventional doctors do when they feel the pulse of a patient. Inter-observer reliability was assessed using three methods: simple percentage agreement, the kappa value, and the AC(1) statistic. The kappa value indicated that the inter-observer reliability in evaluating the pulse signs ranged from poor to moderate, whereas the AC(1) analysis suggested that agreement between the two experts was generally high (with the exception of ‘slippery pulse’). The kappa value indicated that the inter-observer reliability was generally moderate to good (with the exceptions of ‘rough pulse’ and ‘sunken pulse’) and that the AC(1) measure of agreement between the two experts was generally high.
Based on these findings, the authors drew the following conclusion: “Pulse diagnosis is regarded as one of the most important procedures in TKM… This study reveals that the inter-observer reliability in making a pulse diagnosis in stroke patients is not particularly high when objectively quantified. Additional research is needed to help reduce this lack of reliability for various portions of the pulse diagnosis.”
This indicates, I think, that the researchers (who are themselves practitioners of TCM!) are not impressed with the inter-rater reliability of the most commonly used diagnostic tool in TCM/TKM. Imagine this to be true for a commonly used test in conventional medicine; imagine, for instance, that one doctor measuring your blood pressure produces entirely different readings than the next one. Hardly acceptable, don’t you think?
And, of course, inter-rater reliability would be only one of several preconditions for their diagnostic methods to be valid. Other essential preconditions for diagnostic tests to be of value are their specificity and their sensitivity; do they discriminate between healthy and unhealthy, and are they capable of differentiating between severely abnormal findings and those that are just a little out of the normal range?
Until we have answers to all the open questions about each specific alternative diagnostic method, it would be unwise to pretend these tests are valid. Imagine a doctor prescribing a life-long anti-hypertensive therapy on the basis of a blood pressure reading that is little more than guess-work!
Since non-validated diagnostic tests can generate both false positive and false negative results, the danger of using them should not be under-estimated. In a way, invalid diagnostic tests are akin to bogus bomb-detectors (which made headlines recently): both are techniques to identify a problem. If the method generates a false positive result, an alert will be issued in vain, people will get anxious for nothing, time and money will be lost, etc. If the method generates a false negative result, we will assume to be safe while, in fact, we are not. In extreme cases, such an error will cost lives.
It is difficult to call those ‘experts’ who advocate using such tests anything else than irresponsible, I’d say. And it is even more difficult to have any confidence in the treatments that might be administered on the basis of such diagnostic methods, wouldn’t you agree?
This post has an odd title and addresses an odd subject. I am sure some people reading it will ask themselves “has he finally gone potty; is he a bit xenophobic, chauvinistic, or what?” I can assure you none of the above is the case.
Since many years, I have been asked to peer-review Chinese systematic reviews and meta-analyses of TCM-trials submitted to various journals and to the Cochrane Collaboration for publication, and I estimate that around 300 such articles are available today. Initially, I thought they were a valuable contribution to our knowledge, particularly for the many of us who cannot read Chinese languages. I hoped they might provide reliable information about this huge and potentially important section of the TCM-evidence. After doing this type of work for some time, I became more and more frustrated; now I have decided not to accept this task any longer – not because it is too much trouble, but because I have come to the conclusion that these articles are far less helpful than I had once assumed; in fact, I now fear that they are counter-productive.
In order to better understand what I mean, it might be best to use an example; this recent systematic review seems as good for that purpose as any.
Its Chinese authors “hypothesized that the eligible trials would provide evidence of the effect of Chinese herbs on bone mineral density (BMD) and the therapeutic benefits of Chinese medicine treatment in patients with bone loss“. Randomized controlled trials (RCTs) were thus retrieved for a systematic review from Medline and 8 Chinese databases. The authors identified 12 RCTs involving a total of 1816 patients. The studies compared Chinese herbs with placebo or standard anti-osteoporotic therapy. The pooled data from these RCTs showed that the change of BMD in the spine was more pronounced with Chinese herbs compared to the effects noted with placebo. Also, in the femoral neck, Chinese herbs generated significantly higher increments of BMD compared to placebo. Compared to conventional anti-osteoporotic drugs, Chinese herbs generated greater BMD changes.
In their abstract, the part on the paper that most readers access, the authors reached the following conclusions: “Our results demonstrated that Chinese herb significantly increased lumbar spine BMD as compared to the placebo or other standard anti-osteoporotic drugs.” In the article itself, we find this more detailed conclusion: “We conclude that Chinese herbs substantially increased BMD of the lumbar spine compared to placebo or anti-osteoporotic drugs as indicated in the current clinical reports on osteoporosis treatment. Long term of Chinese herbs over 12 months of treatment duration may increase BMD in the hip more effectively. However, further studies are needed to corroborate the positive effect of increasing the duration of Chinese herbs on outcome as the results in this analysis are based on indirect comparisons. To date there are no studies available that compare Chinese herbs, Chinese herbs plus anti-osteoporotic drugs, and anti-osteoporotic drug versus placebo in a factorial design. Consequently, we are unable to draw any conclusions on the possible superiority of Chinese herbs plus anti-osteoporotic drug versus anti-osteoporotic drug or Chinese herb alone in the context of BMD.“
Most readers will feel that this evidence is quite impressive and amazingly solid; they might therefore advocate routinely using Chinese herbs for the common and difficult to treat problem of osteoporosis. The integration of TCM might avoid lots of human suffering, prolong the life of many elderly patients, and save us all a lot of money. Why then am I not at all convinced?
The first thing to notice is the fact that we do not really know which of the ~7000 different Chinese herbs should be used. The article tells us surprisingly little about this crucial point. And even, if we manage to study this question in more depth, we are bound to get thoroughly confused; there are simply too many herbal mixtures and patent medicines to easily identify the most promising candidates.
The second and more important hurdle to making sense of these data is the fact that most of the primary studies originate from inaccessible Chinese journals and were published in Chinese languages which, of course, few people in the West can understand. This is entirely our fault, some might argue, but it does mean that we have to believe the authors, take their words at face value, and cannot check the original data. You may think this is fine, after all, the paper has gone through a rigorous peer-review process where it has been thoroughly checked by several top experts in the field. This, however, is a fallacy; like you and me, the peer-reviewers might not read Chinese either! (I don’t, and I reviewed quite a few of these papers; in some instances, I even asked for translations of the originals to do the job properly but this request was understandably turned down) In all likelihood, the above paper and most similar articles have not been properly peer-reviewed at all.
The third and perhaps most crucial point can only be fully appreciated, if we were able to access and understand the primary studies; it relates to the quality of the original RCTs summarised in such systematic reviews. The abstract of the present paper tells us nothing at all about this issue. In the paper, however, we do find a formal assessment of the studies’ risk of bias which shows that the quality of the included RCTs was poor to very poor. We also find a short but revealing sentence: “The reports of all trials mentioned randomization, but only seven described the method of randomization.” This remark is much more significant than it may seem: we have shown that such studies use such terminology in a rather adventurous way; reviewing about 2000 of these allegedly randomised trials, we found that many Chinese authors call a trial “randomised” even in the absence of a control group (one cannot randomise patients and have no control group)! They seem to like the term because it is fashionable and makes publication of their work easier. We thus have good reason to fear that some/many/most of the studies were not RCTs at all.
The fourth issue that needs mentioning is the fact that very close to 100% of all Chinese TCM-trials report positive findings. This means that either TCM is effective for every indication it is tested for (most unlikely, not least because there are many negative non-Chinese trials of TCM), or there is something very fundamentally wrong with Chinese research into TCM. Over the years, I have had several Chinese co-workers in my team and was invariably impressed by their ability to work hard and efficiently; we often discussed the possible reasons for the extraordinary phenomenon of 0% negative Chinese trials. The most plausible answer they offered was this: it would be most impolite for a Chinese researcher to produce findings which contradict the opinion of his/her peers.
In view of these concerns, can we trust the conclusions of such systematic reviews? I don’t think so – and this is why I have problems with research of this nature. If there are good reasons to doubt their conclusions, these reviews might misinform us systematically, they might not further but hinder progress, and they might send us up the garden path. This could well be in the commercial interest of the Chinese multi-billion dollar TCM-industry, but it would certainly not be in the interest of patients and good health care.
According to Wikipedia, Gua sha involves repeated pressured strokes over lubricated skin with a smooth edge placed against the pre-oiled skin surface, pressed down firmly, and then moved downwards along muscles or meridians.This intervention causes bleeding from capillaries and sub-cutaneous blemishing which usually last for several days. According to a recent article on Gua Sha, it is a traditional healing technique popular in Asia and Asian immigrant communities involving unidirectional scraping and scratching of the skin until ‘Sha-blemishes’ appear.
Gua Sha paractitioners make far-reaching therapeutic claims, e.g.” Gua Sha is used whenever a patient has pain whether associated with an acute or chronic disorder… In addition to resolving musculo skeletal pain, Gua Sha is used to treat as well as prevent common cold, flu, bronchitis, asthma, as well as any chronic disorder involving pain, congestion of Qi and Blood“. Another source informs us that ” Gua Sha is performed to treat systemic toxicity, poor circulation, physical and emotional stress, and migraines. Gua Sha healing promotes the flow of Qi (energy) and blood throughout the body for overall health“.
Gua Sha “blemishes” can look frightful – more like the result of torture than of treatment. Yet with our current craze for all things exotic in medicine, Gua Sha is becoming popular also in Western countries. One German team has even published several RCTs of Gua Sha.
This group treated 40 patients with neck pain either with Gua Sha or locally applied heat packs. They found that, after one week, the pain was significantly reduced in the former compared to the latter group. The same team also published a study with 40 back or neck-pain patients who either received a single session of Gua Sha or were left untreated. The results indicate that one week later, the treated patients had less pain than the untreated ones.
My favoutite article on the subject must be a case report by the same German research team. It describes a woman suffering from chronic headaches. She was treated with a range of interventions, including Gua Sha – and her symptoms improved. From this course of events, the authors conclude that “this case provides first evidence that Gua Sha is effective in the treatment of headaches”
The truth, of course, is that neither this case nor the two RCTs provide any good evidence at all. The case-report is, in fact, a classic example of drawing hilariously over-optimistic conclusions from data that are everything but conclusive. And the two RCTs just show how remarkable placebo-effects can be, particularly if the treatment is exotic, impressive, involves physical touch, is slightly painful and raises high expectations.
My explanation for the observed effects after Gua Sha is quite simple: imagine you have a headache and accidentally injure yourself – say you fall off your bike and the tarmac scrapes off an area of skin on your thigh. This hurts quite a bit and distracts you from your headache, perhaps even to such an extend that you do not feel it any more. As the wound heals, it gets a bit infected and thus hurts for several days; chances are that your headache will be gone for that period of time. Of course, the Gua Sha- effect would be larger because the factors mentioned above (exotic treatment, expectation etc.) but essentially the accident and the treatment work via similar mechanisms, namely distraction and counter-irritation. And neither Gua Sha nor injuring yourself on the tarmac are truly recommendable therapies, in my view.
But surely, for the patient, it does not matter how she gets rid of her headache! The main point is that Gua Sha works! In a way, this attitude is understandable – except, we do not need the hocus pocus of meridians, qi, TCM, ancient wisdom etc. nor do we need to tolerate claims that Gua Sha is “serious medicine” and has any specific effects whatsoever. All we do need is to apply some common sense and then use any other method of therapeutic counter-irritation; that might be more honest, safer and would roughly do the same trick.
No, I am wrong! I forgot something important: it would not be nearly as lucrative for the TCM-practitioner.