Fatally Flawed Study Design in Herbal Medicine Review Article 9 October 2007

Postgraduate Medical Journal, 2007:83:633-637

Fatally Flawed Study Design in Herbal Medicine Review Article 9 October 2007

Postgraduate Medical Journal, 2007: 83:633-637

Fatally Flawed Study Design in Herbal Medicine Review Article 9 October 2007

E. J. Koprowski, M.A.,
Medical Intern
Midwest College of Oriental Medicine
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Re: Fatally Flawed Study Design in Herbal Medicine Review Article

Email E. J. Koprowski, M.A.

Dear Editors,

A recent article, A systematic review of randomized clinical trials of individualized herbal medicine in any indication, published in October, 2007 in the Postgraduate Medical Journal, by R. Guo , P. H. Canter , E. Ernst, of the Peninsula Medical School, Universities of Exeter & Plymouth, Exeter, U.K., warns public health authorities that the effectiveness of individualized, herbal medicine has not been scientifically established. “The findings of this review are particularly pertinent because section 12(1) of the U.K.’s Medicines Act relating to regulation of unlicensed herbal remedies made up to meet the needs of individual patients is presently under review,” the authors note. But this thinly-veiled call for regulation – publicized in the national media in the U.K., in outlets including The Independent and The Guardian, inter alia, is fatally flawed.

The authors fail to take into account the dramatic differences that animate the diagnostic and prescriptive systems of Chinese medicine, Ayurveda, and European homeopathy. The herbs used by doctors in this complementary medical systems are not used in the same way, or for the same purposes. Chinese medicine is energy medicine – and seeks to balance the body and achieve harmony for the patient. But homeopathy is decidedly different, as it uses herbs to create a catalytic reaction in the patient, and thus stimulate his immune system. Ayurveda differs from both of these approaches.

Lumping the herbal treatments of these three, separate medical systems makes no scientific sense – and, may quite literally be comparing apples to oranges. This is a disservice to readers.

To be sure, the article is not totally without merit. The authors note that evidence of efficacy for some herbal medicines, has increased substantially during the past 20 years. The authors also note that the World Health Organization (WHO) has estimated that 80% of the population in developing countries relies primarily upon herbal medicine for basic health care.

But, the authors caution, most clinical trials of herbal medicine have focused on standardized extracts of single herbs or standardized formulae. “The individualized approach, in which patients receive tailored prescriptions comprising a mixture of herbs, is emphasized in most forms of practitioner based herbalism, including European medical herbalism, Chinese herbal medicine and Ayurvedic herbal medicine,” the authors note. “ Evidence from clinical studies of single herb extracts or standardized formulae cannot be generalized to individualized herbal medicine, and claims by practitioners that the latter has an evidence base requires confirmation. The non-standardized nature of individually prepared herbal prescriptions and the consequent increased potential for adverse events and negative interactions means that safety and effectiveness need to be firmly established before such practices can be endorsed.”

It’s an interesting statement, on the surface, but seems to be a bit of pettifoggery when examined closely. The drugs dispensed by allopathic physicians cannot withstand similar scrutiny – and it has been demonstrated, for example, individual patients react differently to the same, allopathic prescriptions. Some have side effects. Some do not. Some have adverse reactions. Some do not. Some are aided in their healing. Some are not. Is this fact cause for concern? Yes. It has given rise to the field of molecular medicine, wherein scientists are seeking to develop individualized therapies for individual patients. But it is far from the norm for conventional, Western medicine.

As the article’s authors show, they scanned Medline and other medical databases and picked studies of randomized, controlled clinical trials of different herbal treatments – and only three studies that they found featured individualized herbal medicine. This was of 1,345 references in the scientific literature.

The study claims that this methodology is rigorous and that the authors have set a new standard that all herbalists must now follow.

“This study sets a new benchmark for the tailored approach: not only must herbalists demonstrate that individualized treatment is superior to placebo, they must also show, for reasons of cost and safety, that it is superior to standardized treatment,” the authors write. “

We respectfully disagree with the authors of the study that their review has somehow set a “new benchmark” for herbalism. Far from it. In fact, we are concerned that the study design, as we outlined above, is so poorly conceived that it renders its findings and recommendations for public policy makers virtually useless. To lump Chinese medicine, Ayruvedic medicine and European homeopathy into one, undistinguishable category is, simply put, poor scholarship.

Education is needed to explain to allopathic medical practitioners and scientists whose work purports to inform allopaths and public health authorities of the differences between Chinese medicine, Ayurveda and homeopathy. The risk of failing to do so is great – regulators may be driven by hysteria, engendered by ill-conceived studies, into restricting the practice of complementary medicine, to the great disadvantage of patients.


1. R. Guo , P. H. Canter , E. Ernst, A systematic review of randomized clinical trials of individualized herbal medicine in any indication, Postgraduate Medical Journal (U.K.), October 2007. 2. Ernst E, Pittler M, Wider B, eds. The desktop guide to complementary and alternative medicine, an evidence based approach , 2nd ed. Mosby Elsevier, 2006.