MD, PhD, FMedSci, FSB, FRCP, FRCPEd

meta-analysis

The discussion whether acupuncture is more than a placebo is as long as it is heated. Crucially, it is also quite tedious, tiresome and unproductive, not least because no resolution seems to be in sight. Whenever researchers develop an apparently credible placebo and the results of clinical trials are not what acupuncturists had hoped for, the therapists claim that the placebo is, after all, not inert and the negative findings must be due to the fact that both placebo and real acupuncture are effective.

Laser acupuncture (acupoint stimulation not with needle-insertion but with laser light) offers a possible way out of this dilemma. It is relatively easy to make a placebo laser that looks convincing to all parties concerned but is a pure and inert placebo. Many trials have been conducted following this concept, and it is therefore highly relevant to ask what the totality of this evidence suggests.

A recent systematic review did just that; specifically, it aimed to evaluate the effects of laser acupuncture on pain and functional outcomes when it is used to treat musculoskeletal disorders.

Extensive literature searches were used to identify all RCTs employing laser acupuncture. A meta-analysis was performed by calculating the standardized mean differences and 95% confidence intervals, to evaluate the effect of laser acupuncture on pain and functional outcomes. Included studies were assessed in terms of their methodological quality and appropriateness of laser parameters.

Forty-nine RCTs met the inclusion criteria. Two-thirds (31/49) of these studies reported positive effects. All of them were rated as being of high methodological quality and all of them included sufficient details about the lasers used. Negative or inconclusive studies mostly failed to demonstrate these features. For all diagnostic subgroups, positive effects for both pain and functional outcomes were more consistently seen at long-term follow-up rather than immediately after treatment.

The authors concluded that moderate-quality evidence supports the effectiveness of laser acupuncture in managing musculoskeletal pain when applied in an appropriate treatment dosage; however, the positive effects are seen only at long-term follow-up and not immediately after the cessation of treatment.

Surprised? Well, I am!

This is a meta-analysis I always wanted to conduct and never came round to doing. Using the ‘trick’ of laser acupuncture, it is possible to fully blind patients, clinicians and data evaluators. This eliminates the most obvious sources of bias in such studies. Those who are convinced that acupuncture is a pure placebo would therefore expect a negative overall result.

But the result is quite clearly positive! How can this be? I can see three options:

  • The meta-analysis could be biased and the result might therefore be false-positive. I looked hard but could not find any significant flaws.
  • The primary studies might be wrong, fraudulent etc. I did not see any obvious signs for this to be so.
  • Acupuncture might be more than a placebo after all. This notion might be unacceptable to sceptics.

I invite anyone who sufficiently understands clinical trial methodology to scrutinise the data closely and tell us which of the three possibilities is the correct one.

Chinese proprietary herbal medicines (CPHMs) are a well-established and a hugely profitable part of Traditional Chinese Medicine (TCM) with a long history in China and elsewhere; they are used for all sorts of conditions, not least for the treatment of common cold. Many CPHMs have been listed in the ‘China national essential drug list’ (CNEDL), the official reference published by the Chinese Ministry of Health. One would hope that such a document to be based on reliable evidence – but is it?

The aim of a recent review was to provide an assessment on the potential benefits and harms of CPHMs for common cold listed in the CNEDL.

The authors of this assessment were experts from the Chinese ‘Centre for Evidence-Based Medicine’ and one well-known researcher of alternative medicine from the UK. They searched CENTRAL, MEDLINE, EMBASE, SinoMed, CNKI, VIP, China Important Conference Papers Database, China Dissertation Database, and online clinical trial registry websites from their inception to 31 March 2013 for clinical studies of CPHMs listed in the CNEDL for common cold.

Of the 33 CPHMs listed in the 2012 CNEDL for the treatment of common cold, only 7 had any type of clinical trial evidence at all. A total of 6 randomised controlled trials (RCTs) and 7 case series (CSs) could be included in the assessments.

All these studies had been conducted in China and published in Chinese. All of them were burdened with poor study design and low methodological quality, and all had to be graded as being associated with a very high risk of bias.

The authors concluded that the use of CPHMs for common cold is not supported by robust evidence. Further rigorous well designed placebo-controlled, randomized trials are needed to substantiate the clinical claims made for CPHMs.

I should state that it is, in my view, most laudable that the authors draw such a relatively clear, negative conclusion. This does certainly not happen often with papers originating from China, and George Lewith, the UK collaborator in this article, is also not known for his critical attitude towards alternative medicine. But there are other, less encouraging issues here to mention.

In the discussion section of their paper, the authors mention that the CNEDL has been approved by the Chinese Ministry of Public Health and is currently regarded as the accepted reference point for the medicines used in China. They also explain that the CNEDL was officially launched and implemented in August 2009. The CNEDL is now up-dated every 3 years, and its 2012 edition contains 520 medicines, including 203 CPHMs. The CPHMs listed in CNEDL cover 137 herbal remedies for internal medicine, 11 for surgery, 20 for gynaecology, 7 for ophthalmology, 13 for otorhinolaryngology and 15 for orthopaedics and traumatology.

Moreover, the authors inform us that about 3,100 medical and clinical experts had been recruited to evaluate the safety, effectiveness and costs of CPHMs. The selection process of medicines into CNEDL was strictly in accordance with the principle that they ‘must be preventive and curative, safe and effective, affordable, easy to use, think highly of both Chinese and Western medicine’. A detailed procedure for evaluation is, however, not available because the files are confidential.

The authors finally state that their paper demonstrates that the selection of CPHMs into the CNEDL is less likely to be ‘evidence-based’ and revealed the sharp contrast between the policy and priority given to by the Chinese government to Traditional Chinese Medicine(TCM).

This surely must be a benign judgement, if there ever was one! I would say that the facts disclosed in this review show that TCM seems to exist in a strange universe where commercial interests are officially allowed to reign supreme over patients’ interests and public health.

If we go on the internet, we find no end of positive claims for TM. The official TM website, for instance, claims that more than 350 peer-reviewed research studies on the TM technique have been published in over 160 scientific journals. These studies were conducted at many US and international universities and research centers, including Harvard Medical School, Stanford Medical School, Yale Medical School, and UCLA Medical School.

This may well be true – but do those studies amount to more than a heap of beans? Let’s find out.

The objective of our Cochrane review was to determine the effectiveness of TM for the primary prevention of cardiovascular disease (CVD). We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 10); MEDLINE (Ovid) (1946 to week three November 2013); EMBASE Classic and EMBASE (Ovid) (1947 to week 48 2013); ISI Web of Science (1970 to 28 November 2013); and Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment Database and Health Economics Evaluations Database (November 2013). We also searched the Allied and complementary Medicine Database (AMED) (inception to January 2014) and IndMed (inception to January 2014). We hand searched trial registers and reference lists of reviews and articles and contacted experts in the field. We applied no language restrictions.

We included randomised controlled trials (RCTs) of at least three months’ duration involving healthy adults or adults at high risk of CVD. Trials examined TM only and the comparison group was no intervention or minimal intervention. We excluded trials that involved multi-factorial interventions. Outcomes of interest were clinical CVD events (cardiovascular mortality, all-cause mortality and non-fatal events) and major CVD risk factors (e.g. blood pressure and blood lipids, occurrence of type 2 diabetes, quality of life, adverse events and costs). Two authors independently selected trials for inclusion, extracted data and assessed the risk of bias.

We identified 4 RCTs with a total of 430 participants for inclusion in this review. The included trials were small, short term (three months) and at risk of bias. In all studies, TM was practised for 15 to 20 minutes twice a day. None of the included studies reported all-cause mortality, cardiovascular mortality or non-fatal endpoints as trials were short term, but one study reported survival rate three years after the trial was completed. In view of the considerable statistical heterogeneity between the results of the studies for the only outcomes reported, systolic blood pressure (I2 = 72%) and diastolic blood pressure (I2 = 66%), we decided not to undertake a meta-analysis. None of the four trials reported blood lipids, occurrence of type 2 diabetes, adverse events, costs or quality of life.

We concluded that there are few trials with limited outcomes examining the effectiveness of TM for the primary prevention of CVD. Due to the limited evidence to date, we could draw no conclusions as to the effectiveness of TM for the primary prevention of CVD. There was considerable heterogeneity between trials and the included studies were small, short term and at overall serious risk of bias. More and larger long-term, high-quality trials are needed.

Even though I am a co-author of this review, I am not entirely sure that the last sentence of our conclusion is totally correct. The TM movement has, in my view, all the characteristics of a cult with all its the dangers that cults entail. This means, I think, we ought to be cautious about TM and sceptical about their research and results. At the risk of provoking harsh criticism, I would even say we should be distrustful of their aims and methods.

As promised, I will try with this post to explain my reservations regarding the new meta-analysis suggesting that individualised homeopathic remedies are superior to placebos. Before I start, however, I want to thank all those who have commented on various issues; it is well worth reading the numerous and diverse comments.

To remind us of the actual meta-analysis, it might be useful to re-publish its abstract (the full article is also available online):

BACKGROUND:

A rigorous and focused systematic review and meta-analysis of randomised controlled trials (RCTs) of individualised homeopathic treatment has not previously been undertaken. We tested the hypothesis that the outcome of an individualised homeopathic treatment approach using homeopathic medicines is distinguishable from that of placebos.

METHODS:

The review’s methods, including literature search strategy, data extraction, assessment of risk of bias and statistical analysis, were strictly protocol-based. Judgment in seven assessment domains enabled a trial’s risk of bias to be designated as low, unclear or high. A trial was judged to comprise ‘reliable evidence’ if its risk of bias was low or was unclear in one specified domain. ‘Effect size’ was reported as odds ratio (OR), with arithmetic transformation for continuous data carried out as required; OR > 1 signified an effect favouring homeopathy.

RESULTS:

Thirty-two eligible RCTs studied 24 different medical conditions in total. Twelve trials were classed ‘uncertain risk of bias’, three of which displayed relatively minor uncertainty and were designated reliable evidence; 20 trials were classed ‘high risk of bias’. Twenty-two trials had extractable data and were subjected to meta-analysis; OR = 1.53 (95% confidence interval (CI) 1.22 to 1.91). For the three trials with reliable evidence, sensitivity analysis revealed OR = 1.98 (95% CI 1.16 to 3.38).

CONCLUSIONS:

Medicines prescribed in individualised homeopathy may have small, specific treatment effects. Findings are consistent with sub-group data available in a previous ‘global’ systematic review. The low or unclear overall quality of the evidence prompts caution in interpreting the findings. New high-quality RCT research is necessary to enable more decisive interpretation.

Since my team had published an RCTs of individualised homeopathy, it seems only natural that my interest focussed on why the study (even though identified by Mathie et al) had not been included in the meta-analysis. Our study had provided no evidence that adjunctive homeopathic remedies, as prescribed by experienced homeopathic practitioners, are superior to placebo in improving the quality of life of children with mild to moderate asthma in addition to conventional treatment in primary care.

I was convinced that this trial had been rigorous and thus puzzled why, despite receiving ‘full marks’ from the reviewers, they had not included it in their meta-analysis. I thus wrote to Mathie, the lead author of the meta-analysis, and he explained: For your trial (White et al. 2003), under domain V of assessment, we were unable to extract data for meta-analysis, and so it was attributed high risk of bias, as specified by the Cochrane judgmental criteria. Our designated main outcome was the CAQ, for which we needed to know (or could at least estimate) a mean and SD for both the baseline and the end-point of the study. Since your paper reported only the change from baseline in Table 3 or in the main text, it is not possible to derive the necessary end-point for analysis.

It took a while and several further emails until I understood: our study did report both the primary (Table 2 quality of life) and secondary outcome measure (Table 3 severity of symptoms). The primary outcome measure was reported in full detail such that a meta-analysis would have been possible. The secondary outcome measure was also reported but not in full detail, and the data provided by us would not lend themselves to meta-analyses. By electing not our primary but our secondary outcome measure for their meta-analysis, Mathie et al were able to claim that they were unable to use our study and reject it for their meta-analysis.

Why did they do that?

The answer is simple: in their methods section, they specify that they used outcome measures “based on a pre-specified hierarchical list in order of greatest to least importance, recommended by the WHO“. This, I would argue is deeply flawed: the most important outcome measure of a study is usually the one for which the study was designed, not the one that some guys at the WHO feel might be important (incidentally, the WHO list was never meant to be applied to meta-analyses in that way).

By following rigidly their published protocol, the authors of the meta-analysis managed to exclude our negative trial. Thus they did everything right – or did they?

Well, I think they committed several serious mistakes.

  • Firstly, they wrote the protocol, which forced them to exclude our study. Following a protocol is not a virtue in itself; if the protocol is nonsensical it even is the opposite. Had they proceeded as is normal in such cases and used our primary outcome measure in their meta-analyses, it is most likely that their overall results would not have been in favour of homeopathy.
  • Secondly, they awarded our study a malus point for the criterium ‘selective outcome reporting’. This is clearly a wrong decision: we did report the severity-outcome, albeit not in sufficient detail for their meta-analysis. Had they not committed this misjudgment, our RCT would have been the only one with an ‘A’ rating. This would have very clearly highlighted the nonsense of excluding the best-rated trial from meta-analysis.

There are several other oddities as well. For instance, Mathie et al judge our study to be NOT free of vested interest. I asked Mathie why they had done this and was told it is because we accepted free trial medication from a homeopathic pharmacy. I would argue that my team was far less plagued by vested interest than the authors of their three best (and of course positive) trials who, as I happen to know, are consultants for homeopathic manufacturers.

And all of this is just in relation to our own study. Norbert Aust has uncovered similar irregularities with other trials and I take the liberty of quoting his comments posted previously again here:

I have reason to believe that this review and metaanalysis in biased in favor of homeopathy. To check this, I compared two studies (1) Jacobs 1994 about the treatment of childhood diarrhea in Nicaragua, (2) Walach 1997 about homeopathic threatment of headaches. The Jacobs study is one of the three that provided ‘reliable evidence’, Walach’s study earned a poor C2.2 rating and was not included in the meta-analyses. Jacobs’ results were in favour of homeopathy, Walach’s not.

For the domains where the rating of Walach’s study was less than that of the Jacobs study, please find citations from the original studies or my short summaries for the point in question.

Domain I: Sequence generation:
Walach:
“The remedy selected was then mailed to a notary public who held a stock of placebos. The notary threw a dice and mailed either the homeopathic remedy or an appropriate placebo. The notary was provided with a blank randomisation list.”
Rating: UNCLEAR (Medium risk of bias)

Jacobs:
“For each of these medications, there was a box of tubes in sequentially numbered order which had been previously randomized into treatment or control medication using a random numbers table in blocks of four”
Rating: YES (Low risk of bias)

Domain IIIb: Blinding of outcome assessor
Walach:
“The notary was provided with a blank randomization list which was an absolutely unique document. It was only handed out after the biometrician (WG) had deposited all coded original data as a printout at the notary’s office. (…) Data entry was performed blindly by personnel not involved in the study. ”
Rating: UNCLEAR (Medium risk of bias)

Jacobs:
“All statistical analyses were done before breaking the randomisation code, using the program …”
Rating: YES (Low risk of bias)

Domain V: Selective outcome reporting

Walach:
Study protocol was published in 1991 prior to enrollment of participants, all primary outcome variables were reported with respect to all participants and the endpoints.
Rating: NO (high risk of bias)

Jacobs:
No prior publication of protocol, but a pilot study exists. However this was published in 1993 only after the trial was performed in 1991. Primary outcome defined (duration of diarrhea), reported but table and graph do not match, secondary outcome (number of unformed stools on day 3) seems defined post hoc, for this is the only one point in time, this outcome yielded a significant result.
Rating: YES (low risk of bias)

Domain VI: Other sources of bias:

Walach:
Rating: NO (high risk of bias), no details given

Jacobs:
Imbalance of group properties (size, weight and age of children), that might have some impact on course of disease, high impact of parallel therapy (rehydration) by far exceeding effect size of homeopathic treatment
Rating: YES (low risk of bias), no details given

In a nutshell: I fail to see the basis for the different ratings in the studies themselves. I assume bias of the authors of the review.

Conclusion

So, what about the question posed in the title of this article? The meta-analysis is clearly not a ‘proof of concept’. But is it proof for misconduct? I asked Mathie and he answered as follows: No, your statement does not reflect the situation at all. As for each and every paper, we selected the main outcome measure for your trial using the objective WHO classification approach (in which quality of life is clearly of lower rank than severity). This is all clearly described in our prospective protocol. Under no circumstances did we approach this matter retrospectively, in the way you are implying. 

Some nasty sceptics might have assumed that the handful of rigorous studies with negative results were well-known to most researchers of homeopathy. In this situation, it would have been hugely tempting to write the protocol such that these studies must be excluded. I am thrilled to be told that the authors of the current new meta-analysis (who declared all sorts of vested interests at the end of the article) resisted this temptation.

On this blog and elsewhere, I have repeatedly cast doubt on the efficacy of homeopathy – not because I have ‘an axe to grind’, as some seem to believe, but because

  1. the assumptions which underpin homeopathy fly in the face of science,
  2. the clinical evidence fails to show that it works beyond a placebo effect.

But was I correct?

A new systematic review and meta-analysis seems to indicate that I was mistaken. It tested the hypothesis that the outcome of an individualised homeopathic treatment (homeopaths would argue that this is the only true approach to homeopathy) is distinguishable from that with placebos.

The review’s methods, including literature search strategy, data extraction, assessment of risk of bias and statistical analysis, were strictly protocol-based. Judgment in seven assessment domains enabled a trial’s risk of bias to be designated as low, unclear or high. A trial was judged to comprise ‘reliable evidence’ if its risk of bias was low or was unclear in one specified domain. ‘Effect size’ was reported as odds ratio (OR), with arithmetic transformation for continuous data carried out as required; OR > 1 signified an effect favouring homeopathy.

Thirty-two eligible RCTs studied 24 different medical conditions in total. Twelve trials were classed ‘uncertain risk of bias’, three of which displayed relatively minor uncertainty and were designated reliable evidence; 20 trials were classed ‘high risk of bias’. Twenty-two trials had extractable data and were subjected to meta-analysis; OR = 1.53 (95% confidence interval (CI) 1.22 to 1.91). For the three trials with reliable evidence, sensitivity analysis revealed OR = 1.98 (95% CI 1.16 to 3.38).

The authors arrived at the following conclusion: medicines prescribed in individualised homeopathy may have small, specific treatment effects. Findings are consistent with sub-group data available in a previous ‘global’ systematic review. The low or unclear overall quality of the evidence prompts caution in interpreting the findings. New high-quality RCT research is necessary to enable more decisive interpretation.

One does not need to be a prophet to predict that the world of homeopathy will declare this article as the ultimate proof of homeopathy’s efficacy beyond placebo. Already the ‘British Homeopathic Association’ has issued the following press release:

Clinical evidence for homeopathy published

Research into the effectiveness of homeopathy as an individualised treatment has produced results that may surprise many from the worlds of science and medicine. The conclusions are reported cautiously, but the new publication is the first of its type to present evidence that medicines prescribed in individualised homeopathy may have specific effects.

The paper, published in the peer-reviewed journal Systematic Reviews,1 reports a rigorous systematic review and meta-analysis of 32 randomised controlled trials (RCTs) in which homeopathic medicines were prescribed on an individual basis to each participant, depending on their particular symptoms.

The overall quality of the RCT evidence was found to be low or unclear, preventing the researchers from reaching decisive conclusions. Three RCTs were identified as “reliable evidence”.

The study was led by Dr Robert Mathie, research development adviser for the British Homeopathic Association, in partnership with a number of collaborators, including colleagues at the Robertson Centre for Biostatistics, University of Glasgow, who independently verified the statistical methods and findings.

“What we found from the statistics,” says Dr Mathie, “is that the effect of individualised treatment using homeopathic medicines was significantly greater than placebos, and that this effect was retained when we included only the three trials with reliable evidence. This tentatively provides proof of concept that homeopathic medicines have clinical treatment effects.”

Surprised? I was stunned and thus studied the article in much detail (luckily the full text version is available online). Then I entered into an email exchange with the first author who I happen to know personally (to his credit, he responded regularly). In the end, this conversation helped me to better understand the review’s methodology; but it also resulted in me being very much underwhelmed by the reliability of the authors’ conclusion.

Normally I would now explain why. But, in this particular case, I thought it would be interesting and helpful to give others the opportunity to examine the article and come up with their own comments. Subsequently I will add my criticisms.

SO PLEASE TAKE SOME TIME TO STUDY THIS PAPER AND TELL US WHAT YOU THINK.

Aromatherapy is one of the most popular of all alternative therapies. It is most certainly a very agreeable experience. But is it more that a bit of pampering? Does it cure any diseases?

If you believe aromatherapists, their treatment is effective for almost everything. And, of course, there are studies to suggest that, indeed, it works for several conditions. But regular readers of this blog will by now know that it is a bad idea to go by just one single trial; we always must rely on the totality of the most reliable evidence. In other words, we must look for systematic reviews. Recently, such an article has been published.

The aim of this review was to systematically assess the effectiveness of aromatherapy for stress management. Seven databases were searched from their inception through April 2014. RCTs testing aromatherapy against any type of control intervention in healthy but stressed persons assessing stress and cortisol levels were considered. Two reviewers independently performed the selection of the studies, data abstraction and validations. The risk of bias was assessed using Cochrane criteria.

Five RCTs met the authors’ inclusion criteria. Most of the RCTs had high risk of bias. Four RCTs tested the effects of aroma inhalation compared with no treatment, no aroma, and no odour oil. The meta-analysis of these data suggested that aroma inhalation had favourable effects on stress management. Three RCTs tested aroma inhalation on saliva or serum cortisol level compared to controls, and the meta-analysis of these data failed to show significant difference between two groups

The authors concluded that there is limited evidence suggesting that aroma inhalation may be effective in controlling stress. However, the number, size and quality of the RCTs are too low to draw firm conclusions.

This is by no means the only systematic review of this area. In fact, there are so many that, in 2012, we decided to do an overview of systematic reviews evaluating the effectiveness of aromatherapy. We searched 12 electronic databases and our departmental files without restrictions of time or language. The methodological quality of all systematic reviews was evaluated independently by two authors. Of 201 potentially relevant publications, 10 met our inclusion criteria. Most of the systematic reviews were of poor methodological quality. The clinical subject areas were hypertension, depression, anxiety, pain relief, and dementia. For none of the conditions was the evidence convincing. Our conclusion: due to a number of caveats, the evidence is not sufficiently convincing that aromatherapy is an effective therapy for any condition.

So, what does all of this mean? I think it indicates that most of the claims made by aromatherapists are not evidence-based. Or, to express it differently: aromatherapy is hardly more than a bit of old-fashioned pampering – nothing wrong with that, of course, as long as you don’t fall for the hype of those who promote it.

Blinding patients in clinical trials is a key methodological procedure for minimizing bias and thus making sure that the results are reliable. In alternative medicine, blinding is not always straight forward, and many studies are therefore not patient-blinded. We all know that this can introduce bias into a trial, but how large is its effect on study outcomes?

This was the research question addressed by a recent systematic review of randomized clinical trials with one sub-study (i.e. experimental vs control) involving blinded patients and another, otherwise identical, sub-study involving non-blinded patients. Within each trial, the researchers compared the difference in effect sizes (i.e. standardized mean differences) between the two sub-studies. A difference <0 indicates that non-blinded patients generated a more optimistic effect estimate. The researchers then pooled the differences with random-effects inverse variance meta-analysis, and explored reasons for heterogeneity.

The main analysis included 12 trials with a total of 3869 patients. Ten of these RCTs were studies of acupuncture. The average difference in effect size for patient-reported outcomes was -0.56 (95% confidence interval -0.71 to -0.41), (I(2 )= 60%, P = 0.004), indicating that non-blinded patients exaggerated the effect size by an average of 0.56 standard deviation, but with considerable variation. Two of the 12 trials also used observer-reported outcomes, showing no indication of exaggerated effects due lack of patient blinding.

There was an even larger effect size difference in the 10 acupuncture trials [-0.63 (-0.77 to -0.49)], than in the two non-acupuncture trials [-0.17 (-0.41 to 0.07)]. Lack of patient blinding was also associated with increased attrition rates and the use of co-interventions: ratio of control group attrition risk 1.79 (1.18 to 2.70), and ratio of control group co-intervention risk 1.55 (0.99 to 2.43).

The authors conclude that this study provides empirical evidence of pronounced bias due to lack of patient blinding in complementary/alternative randomized clinical trials with patient-reported outcomes.

This is a timely, rigorous and important analysis. In alternative medicine, we currently see a proliferation of trials that are not patient-blinded. We always suspected that they are at a high risk of generating false-positive results – now we know that this is, in fact, the case.

What should we do with this insight? In my view, the following steps would be wise:

  1. Take the findings from the existing trials that are devoid of patient-blinding with more than just a pinch of salt.
  2. Discourage the funding of future studies that fail to include patient-blinding.
  3. If patient-blinding is truly and demonstrably impossible – which is not often the case – make sure that the trialists at least include blinding of the assessors of the primary outcome measures.

If you are pregnant, a ‘breech presentation’ is not good news. It occurs when the fetus presents ‘bottom-down’ in the uterus. There are three types:

  • Breech with extended legs (frank) – 85% of cases
  • Breech with fully flexed legs (complete)
  • Footling (incomplete) with one or both thighs extended

The significance of breech presentation is its association with higher perinatal mortality and morbidity when compared to cephalic presentations. This is due both to pre-existing congenital malformation, increased incidence of breech in premature deliveries and increased risk of intrapartum trauma or asphyxia. Caesarean section has been adopted as the ‘normal’ mode of delivery for term breech presentations in Europe and the USA, as the consensus is that this reduces the risk of birth-related complications.

But Caesarian section is also not a desirable procedure. Something far less invasive would be much more preferable, of course. This is where the TCM-practitioners come in. They claim they have the solution: moxibustion, i.e. the stimulation of acupuncture points by heat. But does it really work? Can it turn the fetus into the correct position?

This new study aimed to assess the efficacy of moxibustion (heating of the acupuncture needle with an igniting charcoal moxa stick) with acupuncture for version of breech presentations to reduce their rate at 37 weeks of gestation and at delivery. It was a randomized, placebo-controlled, single-blind trial including 328 pregnant women recruited in a university hospital center between 33 4/7 and 35 4/7 weeks of gestation. Moxibustion with acupuncture or inactivated laser (placebo) treatment was applied to point BL 67 for 6 sessions. The principal endpoint was the percentage of fetuses in breech presentation at 37 2/7 weeks of gestation.

The results show that the percentage of fetuses in breech presentation at 37 2/7 weeks of gestation was not significantly different in both groups (72.0 in the moxibustion with acupuncture group compared with 63.4% in the placebo group).

The authors concluded that treatment by moxibustion with acupuncture was not effective in correcting breech presentation in the third trimester of pregnancy.

You might well ask why on earth anyone expected that stimulating an acupuncture point would turn a fetus in the mother’s uterus into the optimal position that carries the least risk during the process of giving birth. This is what proponents of this technique say about this approach:

During a TCM consultation to turn a breech baby the practitioner will take a comprehensive case history, make a diagnosis and apply the appropriate acupuncture treatment.  They will assess if moxibustion might be helpful. Practitioners will then instruct women on how to locate the appropriate acupuncture points and demonstrate how to safely apply moxa at home. The acupuncture point UB 67 is the primary point selected for use because it is the most dynamic point to activate the uterus.  Its forte is in turning malpositioned babies.  It is located on the outer, lower edge of both little toenails. According to TCM theory, moxa has a tonifying and warming effect which promotes movement and activity.  The nature of heat is also rising.  This warming and raising effect is utilised to encourage the baby to become more active and lift its bottom up in order to gain adequate momentum to summersault into the head down position. This technique can also be used to reposition transverse presentation, a situation where the baby’s has its shoulder or back pointing down, or is lying sideways across the abdomen.

Not convinced? I can’t say I blame you!

Clearly, we need to know what the totality of the most reliable evidence shows; and what better than a Cochrane review to inform us about it? Here is what it tells us:

Moxibustion was not found to reduce the number of non-cephalic presentations at birth compared with no treatment (P = 0.45). Moxibustion resulted in decreased use of oxytocin before or during labour for women who had vaginal deliveries compared with no treatment (risk ratio (RR) 0.28, 95% confidence interval (CI) 0.13 to 0.60). Moxibustion was found to result in fewer non-cephalic presentations at birth compared with acupuncture (RR 0.25, 95% CI 0.09 to 0.72). When combined with acupuncture, moxibustion resulted in fewer non-cephalic presentations at birth (RR 0.73, 95% CI 0.57 to 0.94), and fewer births by caesarean section (RR 0.79, 95% CI 0.64 to 0.98) compared with no treatment. When combined with a postural technique, moxibustion was found to result in fewer non-cephalic presentations at birth compared with the postural technique alone (RR 0.26, 95% CI 0.12 to 0.56).

In other words, there is indeed some encouraging albeit not convincing evidence! How can this be? There is no plausible explanation why this treatment should work!

But there is a highly plausible explanation why the results of many of the relevant trials are false-positive thus rendering a meta-analysis false-positive as well. I have repeatedly pointed out on this blog that practically all Chinese TCM-studies report (false) positive results; and many of the studies included in this review were done in China. The Cochrane review provides a strong hint about the lack of rigor in its ‘plain language summary':

The included trials were of moderate methodological quality, sample sizes in some of the studies were small, how the treatment was applied differed and reporting was limited. While the results were combined they should be interpreted with caution due to the differences in the included studies. More evidence is needed concerning the benefits and safety of moxibustion.

So, would I recommend moxibustion for breech conversion? I don’t think so!

The question whether infant colic can be effectively treated with manipulative therapies might seem rather trivial – after all, this is a benign condition which the infant quickly grows out of. However, the issue becomes a little more tricky, if we consider that it was one of the 6 paediatric illnesses which were at the centre of the famous libel case of the BCA against my friend and co-author Simon Singh. At the time, Simon had claimed that there was ‘not a jot of evidence’ for claiming that chiropractic was an effective treatment of infant colic, and my systematic review of the evidence strongly supported his statement. The BCA eventually lost their libel case and with it the reputation of chiropractic. Now a new article on this intriguing topic has become available; do we have to reverse our judgements?

The aim of this new systematic review was to evaluate the efficacy or effectiveness of manipulative therapies for infantile colic. Six RCTs of chiropractic, osteopathy or cranial osteopathy alone or in conjunction with other interventions were included with a total of 325 infants. Of the 6 included studies, 5 were “suggestive of a beneficial effect” and one found no evidence of benefit. Combining all the RCTs suggested that manipulative therapies had a significant effect. The average crying time was reduced by an average of 72 minutes per day. This effect was sustained for studies with a low risk of selection bias and attrition bias. When analysing only those studies with a low risk of performance bias (i.e. parental blinding) the improvement in daily crying hours was no longer statistically significant.

The quality of the studies was variable. There was a generally low risk of selection bias but a high risk of performance bias. Only one of the studies recorded adverse events and none were encountered.

From these data, the authors drew the following conclusion: Parents of infants receiving manipulative therapies reported fewer hours crying per day than parents whose infants did not and this difference was statistically significant. Most studies had a high risk of performance bias due to the fact that the assessors (parents) were not blind to who had received the intervention. When combining only those trials with a low risk of such performance bias the results did not reach statistical significance.

Does that mean that chiropractic does work for infant colic? No, it does not!

The first thing to point out is that the new systematic review included not just RCTs of chiropractic but also osteopathy and cranio-sacral therapy.

The second important issue is that the effects disappear, once performance bias is being accounted for which clearly shows that the result is false positive.

The third relevant fact is that the majority of the RCTs were of poor quality. The methodologically best studies were negative.

And the fourth thing to note is that only one study mentioned adverse effects, which means that the other 5 trials were in breach of one of rather elementary research ethics.

What makes all of this even more fascinating is the fact that the senior author of the new publication, George Lewith, is the very expert who advised the BCA in their libel case against Simon Singh. He seems so fond of his work that he even decided to re-publish it using even more misleading language than before. It is, of course, far from me to suggest that his review was an attempt to white-wash the issue of chiropractic ‘bogus’ claims. However, based on the available evidence, I would have formulated conclusions which are more than just a little different from his; something like this perhaps:

The current best evidence suggests that the small effects that emerge when we pool the data from mostly unreliable studies are due to bias and therefore not real. This systematic review therefore fails to show that manipulative therapies are effective. It furthermore points to a serious breach of research ethics by the majority of researchers in this field.

A recent meta-analysis evaluated the efficacy of acupuncture for treatment of irritable bowel syndrome (IBS) and arrived at bizarrely positive conclusions.

The authors state that they searched 4 electronic databases for double-blind, placebo-controlled trials investigating the efficacy of acupuncture in the management of IBS. Studies were screened for inclusion based on randomization, controls, and measurable outcomes reported.

Six RCTs were included in the meta-analysis, and 5 articles were of high quality.  The pooled relative risk for clinical improvement with acupuncture was 1.75 (95%CI: 1.24-2.46, P = 0.001). Using two different statistical approaches, the authors confirmed the efficacy of acupuncture for treating IBS and concluded that acupuncture exhibits clinically and statistically significant control of IBS symptoms.

As IBS is a common and often difficult to treat condition, this would be great news! But is it true? We do not need to look far to find the embarrassing mistakes and – dare I say it? – lies on which this result was constructed.

The largest RCT included in this meta-analysis was neither placebo-controlled nor double blind; it was a pragmatic trial with the infamous ‘A+B versus B’ design. Here is the key part of its methods section: 116 patients were offered 10 weekly individualised acupuncture sessions plus usual care, 117 patients continued with usual care alone. Intriguingly, this was the ONLY one of the 6 RCTs with a significantly positive result!

The second largest study (as well as all the other trials) showed that acupuncture was no better than sham treatments. Here is the key quote from this trial: there was no statistically significant difference between acupuncture and sham acupuncture.

So, let me re-write the conclusions of this meta-analysis without spin, lies or hype: These results of this meta-analysis seem to indicate that:

  1. currently there are several RCTs testing whether acupuncture is an effective therapy for IBS,
  2. all the RCTs that adequately control for placebo-effects show no effectiveness of acupuncture,
  3. the only RCT that yields a positive result does not make any attempt to control for placebo-effects,
  4. this suggests that acupuncture is a placebo,
  5. it also demonstrates how misleading studies with the infamous ‘A+B versus B’ design can be,
  6. finally, this meta-analysis seems to be a prime example of scientific misconduct with the aim of creating a positive result out of data which are, in fact, negative.
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