This is the first paragraph from Ben Goldacre’s recent comment piece Benefits and risks of homeopathy in The Lancet‘s November 17 edition.
Five large meta-analyses of homoeopathy trials have been done. All have had the same result: after excluding methodologically inadequate trials and accounting for publication bias, homoeopathy produced no statistically significant benefit over placebo. 1–5
(1) Kleijnen J, Knipschild P, ter Riet G. Clinical trials of homoeopathy. BMJ 1991; 302: 316–23.
(2) Boissel JP, Cucherat M, Haugh M, Gauthier E. Critical literature review on the effectiveness of homoeopathy: overview of data from homoeopathic medicine trials. Brussels, Belgium: Homoeopathic Medicine Research Group. Report to the European Commission. 1996: 195–210.
(3) Linde K, Melchart D. Randomized controlled trials of individualized homeopathy: a state-of-the-art review. J Alter Complement Med 1998; 4: 371–88.
(4) Cucherat M, Haugh MC, Gooch M, Boissel JP. Evidence of clinical efficacy of homeopathy: a meta-analysis of clinical trials. Eur J Clin Pharmacol 2000; 56: 27–33
(5) Shang A, Huwiler-Müntener K, Nartey L, et al. Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy. Lancet 2005; 366: 726–32
Note that Goldacre omits the Linde et al meta-analysis published in The Lancet in 1997 (6) from his listed studies.
Below are comments and conclusions from each of these studies. Remember, Goldacre is saying that they each support his assertion that homeopathy has no statistically significant benefit over placebo.