Sunday, April 13, 2014

Assessment of Homeopathy by NHMRC

by Felipe Nogueira

Homeopathy is type of complementary and alternative (CAM) medicine based on two principles. The first, "like cure like", states that substances can be used to treat the same symptoms they cause. The second principle is the potentisation: the substance is diluted and agitated several times. Homeopaths use the C notation to indicate that 1 part of the substance was diluted in 100 parts of water (or alcohol). Then, 200C, used in the prepation of Oscillococcinum, indicates that, firstly, 1 part of the substance was diluted in 100 parts of water. After that, 1 part of the result of each dilution was diluted in 100 parts of water until it totalizes 200 dilutions. This means that, by the end of 200 dilutions, 1 part of the original substance was diluted in 100200 parts of water. Homeopaths called this process potentisation because they believe - as crazy as it sounds - the more diluted the homeopathic preparation, more strong it is.

The National Health and Medical Research Council (NHMRC), as stated on its website, is Australia’s leading expert body promoting the development and maintenance of public and individual health standards. Its mission is working to a make a more healthy Australia.  

Recently, NHMRC realized a big assessment of the evidence of the effectiveness of Homeopathy. This assessment had been done because is NHMRC's role to provide the best evidence to help australians to make health decisions. And this includes decisions regarding the use of CAM. NHMRC published a draft for public consultation*. Any aditional evidence may be submitted for analysis until the end of May. 

Evidence analysed by NHMRC
As described on the draft, the assessment objective is to answer the question "Is homeopathy an effective treatment for health conditions, compared with no homeopathy, or compared to other treatments?". To achieve that goal, NHMRC considered 57 systematic reviews that assessed the effectiveness of homeopathy for tretating 68 health conditions. It is important to highlight the following:
  • NHMRC considered "evidence" only prospective and controlled studies in humans; it does not included individual experience, testimonials or case reports, or research that was not done using standard methods
  • NHMRC considered papers submitted by the public, Australian Homeopathy Association and Australian Medical Fellowship of Homeopathy
  • NHMRC did not consider evidence whether or not homeopathy is effective for preventing health conditions or whether it's good for general health. 
Homeopathy compared with placebo
The systematic reviews considered by NHMRC found studies that compared homeopathy with placebo for 55 health conditions.

For 13 health conditions, it was found that homeopathy was reported to be not better than placebo in at least the large majority of reliable studies (well-done and with enough participants). These conditions were: adenoid vegetation in children, asthma, anxiety or strees-related conditions, diarrhoea in children, headache and migraine, muscle soreness, inducing or shortening labour, pain due to dental work, pain due to orthopaedic surgery, postoperative ileus, premenstrual syndrome, upper respiratory tract infections, warts.

For 14 conditions, some studies reported that homeopathy was more effective than placebo, but NHMRC considered those studies not reliable, because they were not well done or had too few participants. These conditions were: allergic rhinitis, attention deficit/hyperactivity disorder in children, bruising, chronic fatigue syndrome, diarrhoea in children, fibromyalgia, hot flushes in women who have had brest cancer, HIV infection, influenza-like illness, rheumatoid arthritis, sinusitis, sleep disturbances or circadian rhythm disturbances, stomatitis due to chemotherapy, ulcers.

For 29 health condition, only one study that compared homeopathy with placebo was found. These studies were considered not realible, because they were poor or unknow quality, or they had too few participants It was not possible to make any conclusion about whether homeopathy was effective or not for these conditions that were the following: acne vulgaris, acute otitis media in children, acute ankle sprain, acute trauma, amoebiasis and giardiasis, ankylosing spondylitis, boils and pyoderma, Broca's aphasia in people who have had a stroke, bronchitis, cholera, cough,  chronic polyarthritis,  dystocia, eczema,  heroin addiction, knee joint haematoma,  lower pack pain, nausea and vomiting associated with chemotherapy, oral lichen planus, osteoarthrits, proctocolitis, postoperative pain-agitation syndrome, radiodermatitis, seborrhoeic dermatitis, supression in lactation after childbirth in woman who elect not to breastfeed, stroke, traumatic brain injury, uraemic pruritis, vein problems due to cannulas in people receiving chemotherapy. 

Homeopathy compared with other treatments
For 8 conditions, some studies reported that homeopathy was more effective than Placebo. NHMRC considered those studies not reliable, because they were not well done or had few participants. Those conditions were: acute otitis media or acute otitis media with effusion in children, allergic rhinitis, anxiety or stress-related conditions, depression, eczema, non-allergic rhinitis, osteoarthritis, upper respiratory tract infection. 

For 7 conditions, only one study that compared with homeopathy with placebo was found. These studies were considered not realible, because they were poor or unknow quality, or they had too few participantsFor these conditions, it was not possible to make any conclusion about whether homeopathy was effective or not. These conditions were: burns (second and third degree), fibromyalgia, irritable bowel syndrome, malaria, proctocolitis, recurrent vulvovaginal candidiasis, rheumatoid arthritis. 

Studies that were not found
The sytematic reviews considered by NHMRC searched but didn't find studies for the following 7 health conditions: borderline personality disorder, dementia, constipation in children, glaucoma, nocturnal enuresis, lower urinary tract symptoms in men, and chronic facil pain. 

Conclusion
The conclusion by NHMRC is very clear and can be read on the page 10 of the draft's document: 

NHMRC concludes that the assessment of the evidence from research in humans does not show that homeopathy is effective for treating the range of health conditions considered. 
There were no health conditions for which there was reliable evidence that homeopathy was effective. No good-quality, well-designed studies with enough participants for a meaningful result reported either that homeopathy caused greater health improvements than a substance with no effect on the health condition (placebo), or that homeopathy caused health improvements equal to those of another treatment.  
Comments
NHMRC published four very detailed documents*. The systematic reviews considered were extensively discussed on those documents; the forms for assessment of the quality of each study were published. These information are all avaiable on-line.  Not surprisingly, Edzard Ernst, the first professor of CAM in the world, considered the NHMRC's assessment the most through and most independent in the history of homeopathy. According to Enrst, this assessment merged two perspectives on homeopathy - skeptics' and evidence based medicine advogates' - isolating the believers and rendering their position no longer tenable. I don't think I need to say anything else besides the following comment by Ernst:
it appears more and more as though homeopathy is fast degenerating into a cult characterised by the unquestioning commitment and unconditional submission of its members who are too heavily brain-washed to realize that their fervour has isolated them from the rational sections of society. And a cult is hardly what we need in heath care, I should think. It seems to me therefore that these intriguing developments might finally end the error that homeopathy represented for nearly 200 years.
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All documents published by NHMRC regarding its assessment of homeopathy can be found here

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