What do the best studies in homeopathy show?
By the ‘best studies’ people usually mean comprehensive systematic reviews, which analyse the results from all available randomised controlled trials (RCTs) on a given subject.
The most robust data on efficacy of homeopathy comes from a 2014 meta-analysis of placebo-controlled double-blind randomised controlled trials which found that homeopathic medicines, when prescribed during individualised treatment, are 1.5- to 2.0-times more likely to have a beneficial effect than placebo.1
This study is one of the four most recent comprehensive systematic reviews conducted by Dr Robert Mathie within a ten-year programme of work. When taken collectively, this programme of work includes some important positive findings for homeopathy.
Further research is needed to consolidate and expand the current clinical trial evidence base in homeopathy. However, these systematic reviews and meta-analyses have helped to identify area of most promise, helping researchers know where to focus their efforts in order to inform decision-makers and patients about the potential of homeopathic treatments.
For further details of these latest systematic reviews plus historical systematic reviews on homeopathy (1991 – 2005) see Clinical Trials Overview.
If there are positive studies, why do some people still refuse to accept what the evidence says?
The issue appears to be one of ‘plausibility bias’ i.e. those who hold a prior belief that homeopathy is impossible, will view the results of research differently from those who believe homeopathy may work or does work.
As far back as 1991, the authors of the first of these major studies expressed this very clearly in their own paper:2
“The amount of positive evidence even among the best studies came as a surprise to us. Based on this evidence we would be ready to accept that homoeopathy can be efficacious, if only the mechanism of action were more plausible.”
It is worth noting that none of Dr Mathie’s reviews were not considered for inclusion in the 2015 NHMRC Homeopathy Review because they were published at a later date and because they do not provide data on evidence for individual medical conditions. However, it is hard to understand why the 2017 EASAC position statement on homeopathy makes no mention of these four reviews, being the most relevant and robust data on the topic at the time.
