Ludtke R, Rutten AL. The conclusions on the effectiveness of homeopathy highly depend on the set of analyzed trials. Journal of Clinical Epidemiology. 2008, 61(12):1197-204. [PubMed abstract]
Rutten AL, Stolper CF. The 2005 meta-analysis of homeopathy: the importance of post-publication data. Homeopathy. 2008, 97(4):169-77. [PubMed abstract]
Based on all high-quality studies, homeopathy had a significant effect beyond placebo…. Shang’s results and conclusions are less definite than had been presented.
Read about more scientific research into homeopathy
The identity of the trials analysed was not revealed.
In this re-analysis, the 21 higher quality trials of homeopathy were identified, re-extracted and analysed with sensitivity analysis for the influence of single indications and other meaningful subsets of the high quality trials.
Subsets were defined according to sample size, type of homeopathy, type of publication, and treated condition. The overall odds ratios (ORs) were estimated using random effect meta-analyses.
The results show that the ‘larger high quality’ trials of homeopathy on which the original conclusions were based were highly heterogeneous, comprising 8 trials on 8 different indications, and were not matched by indication with those of conventional medicine.
The method of assessment of trial quality was unclear and differed from previous meta-analyses. However the quality of trials of homeopathy is better than of trials conventional of conventional medicine.
Based on all high-quality studies, homeopathy had a significant effect beyond placebo. When the set of analyzed trials was successively restricted to larger patient numbers, the ORs varied and the P-values increased. Shang’s negative results were largely due to one trial on preventing muscle soreness in 400 long-distance runners.
The authors concluded that the results of the meta-analysis are very sensitive to the threshold defining ‘large’ clinical trials and that, because of the heterogeneity between the trials and methodological issues, Shang’s results and conclusions are less definite than had been presented.
*Shang A, Huwiler-Müntener K, Nartey L, Jüni P, Dörig S, Sterne JA, Pewsner D, Egger M. Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy. Lancet. 2005 Aug 27-Sep 2;366(9487):726-32. [PubMed abstract]
From The Society of Homeopath’s website:
Common findings throughout these studies included problems with variable trial quality, variable trial design, publication bias and the small number of studies available in total. Despite these limitations, four of the five reviews found that even high quality trials produced positive results in favour of homeopathy. The authors called for more research with a focus on the role of homeopathy in the treatment of specific disease conditions and an emphasis on larger, high quality studies.
The most recent review by the Swiss team of Shang et al. was published in the Lancet alongside an editorial entitled The End of Homeopathy. This understandably sparked an intense media debate. The study now lacks credibility since scientists worldwide have drawn attention to serious flaws in how the study was conducted and how the results were presented.[10] ,[11] ,[12] . Most notably the study does not meet the ‘quality-control’ criteria for publication of meta-analyses as described in the Lancet itself in 1999.[13]
Find out more…Systematic reviews should be ‘transparent and reproducible’ (Ernst, 2007) yet the initial study gave no information about which trials had been used in the analysis. This is unacceptable in scientific publications. When the necessary information was finally released allowing other researchers to replicate the study, a team produced two articles challenging Shang’s findings, describing flaws which make the results unreliable (Ludtke 2008, Rutten 2008).
Ernst E. Understanding Research in Complementary and Alternative Medicine. Holistic Therapy Books, 2007
Ludtke R, Rutten ALB. The conclusions on the effectiveness of homeopathy highly depend on the set of analyzed trials. J Clin Epidemiol, 2008
Rutten ALB, Stolper CF. The 2005 meta-analysis of homeopathy: the importance of post-publication data. Homeopathy, 2008
10. Bell, I. All Evidence is Equal, but Some Evidence is More Equal than Others: Can Logic Prevail over Emotion in the Homeopathy Debate? 2005, JACM, 11(5): 763-9
11. Frass, M et al. Bias in the Trial and Reporting of Trials of Homeopathy: A Fundamental Breakdown in Peer Review and Standards? JACM, 2005, 11(5): 780-2
12. Helmut K, et al. Failure to Exclude False Negative Bias: A Fundamental Flaw in the Trial of Shang et al. JACM, 2005; 11(5): 783
13. Moher D, et al. Improving the quality of reports of meta-analyses of randomised controlled trials: the QUOROM statement. Quality of Reporting of Meta-analyses. Lancet, 1999; 354(9193):1896-900