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.