Systematic review and meta-analysis of randomised controlled trials (RCTs) in homeopathy
Authors: Robert T Mathie,1 Lynn A Legg,2 Jürgen Clausen,3 Jonathan R T Davidson,4 Suzanne M Lloyd,5 Ian Ford 5
1 British Homeopathic Association, Luton, UK
2 Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
3 Karl und Veronica Carstens-Stiftung, Essen, Germany
4 Department of Psychiatry and Behavioral Science, Duke University Medical Center,
Durham, North Carolina, USA
5 Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UK
Enabled by a research grant from the Manchester Homeopathic Clinic, the programme of work will ultimately examine all relevant papers previously identified in a comprehensive overview of the research literature (Mathie et al. 2013). The review work reflects the key differences between the following: peer-reviewed and non-peer-reviewed articles; placebo-controlled and other-than-placebo controlled trials; individualised and non-individualised homeopathy; treatment and prevention.
The first phase of the review programme, whose methods are outlined in the study protocol, examined 32 eligible peer-reviewed, placebo-controlled trials of individualised homeopathic treatment. The paper reporting the findings of this review (Mathie et al. 2014) was published in December 2014 in the journalSystematic Reviews: a statistically significant overall effect of individualised homeopathic treatment was identified over that of placebos.
Such significant effects may be difficult to observe readily in any one given placebo-controlled trial of individualised homeopathy, in which both groups of participants have had exactly the same type of empathetic homeopathic consultation, followed by the homeopathic prescription or the placebo. Our findings cautiously suggest that individually prescribed homeopathic medicines have a specific effect, at least for the majority of medical conditions included in our meta-analysis.
The overall quality of the RCT evidence was judged to be low or unclear: only 3 of the trials in the systematic review were judged to comprise ‘reliable evidence’ (Bell et al. 2004; Jacobs et al. 1994; Jacobs et al. 2001). This indicates the need for caution in interpreting the review’s findings, and an obvious requirement for new and higher-quality research in this field.
Exploring a less strict data extraction approach, thereby relaxing the criteria for ‘reliable evidence’, we identified a fourth RCT in that higher-quality category (White et al. 2003): inclusion of this trial in meta-analysis did not produce an overall different statistical result or conclusion.
The second phase of the review programme, whose methods are outlined in a separate study protocol, is examining 96 peer-reviewed, placebo-controlled trials of non-individualised homeopathic treatment. From March 2016, this grant-funded work has been continuing under the management of the Homeopathy Research Institute (HRI).
As stated in the study protocols, the aims of this systematic review programme reflect matters of study quality (including internal validity and model validity), and focusing on two key issues: (1) in a global meta-analysis, to ascertain if treatment using homeopathic medicines can be distinguished from the same form of treatment but using placebo medicines; (2) in condition-specific meta-analyses, to quantify any effect of homeopathic treatment for medical conditions in which there is greater than one placebo-controlled RCT.
Bell I, Lewis D, Brooks A, Schwartz G, Lewis S, Walsh B, Baldwin C (2004). Improved clinical status in fibromyalgia patients treated with individualized homeopathic remedies versus placebo. Rheumatology; 43:577–582.
Jacobs J, Jimenez LM, Gloyds SS, Gale JL, Crothers D (1994). Treatment of acute childhood diarrhea with homeopathic medicine; a randomized clinical trial in Nicaragua. Pediatrics; 93:719–725.
Jacobs J, Springer DA, Crothers D (2001). Homeopathic treatment of acute otitis media in children: a preliminary randomized placebo-controlled trial. Pediatric Infectious Disease Journal; 20:177–183.
Mathie RT, Hacke D, Clausen J, Nicolai T, Riley DS, Fisher P (2013). Randomised controlled trials of homeopathy in humans: characterising the research journal literature for systematic review. Homeopathy; 102: 3–24.
Mathie RT, Lloyd SM, Legg LA, Clausen J, Moss S, Davidson JRT, Ford I (2014). Randomised placebo-controlled trials of individualised homeopathic treatment: systematic review and meta-analysis. Systematic Reviews; 3: 142.
White A, Slade P, Hunt C, Hart A, Ernst E (2003). Individualised homeopathy as an adjunct in the treatment of childhood asthma: a randomised placebo controlled trial. Thorax; 58:317–321.