Clinical research in homeopathy: randomised, controlled or outcome studies?
22 December 2017 (online)
Much has been made of the potential role that real-world outcomes research might play in the scientific validation of homeopathy. The hope is to speak loudly to the audiences who need to be convinced of the huge contribution homeopathic medicine has to make to health care,[ 1 ] specifically the medical establishment and funders of health care—governments and insurance organizations. The place of the blinded, randomized, controlled trial (RCT) in assessing forms of complementary therapies and homeopathy has been widely questioned, with some authors even apparently advocating the view that the time for RCTs in homeopathy is past[ 2 ] and that energy, time and money spent on this form of investigation is bound to be wasted in the long run, as single RCTs of single conventionally diagnosed medical conditions will, at most sway opinion very slightly in favour for the use of homeopathy in that particular condition, but are very unlikely to change perceptions about homeopathy as a method of helping a large number of people suffering from a very wide range of diagnoses.
The opposite stance is equally strongly defended. Supporters of the continued relevance of performing RCTs in homeopathy point to the fact that this is the best and most accepted method yet devised for looking in detail at the efficacy of a particular medical intervention. If we want homeopathy to be accepted by the wider medical community, we must expect to use the standard methods of assessment. Anything else looks like cowardice and carries the message that we lack confidence that homeopathy can show itself as an effective form of therapy.[ 3 ] Meta-analyses of RCTs of homeopathy against placebo, showing positive results in favour of homeopathy have been seized upon by the homeopathic community as some kind of answer to a prayer.[ 4,5 ] Less positive results and criticisms[ 6 ] are generally conveniently forgotten in the warm glow of pleasure that at last we have acceptable evidence that we are doing something worthwhile.
Some will say ‘as if we didn’t know that already!’ and this statement goes to the heart of what kind of evidence can be collected to convince funding bodies to invest in homeopathic medicine. As homeopathic physicians, we are all sure that homeopathy is quite effective quite a lot of the time in a wide range of clinical situations, many of which are not easily amenable to other interventions. There have been a number of outcome studies which have aimed to ‘firm up’ this conviction by looking at large groups of patients treated with homeopathy in real-world settings (away from the artificial world of the RCT), sometimes by a range of practitioners in several countries in comparison with conventionally treated patients for a small number of well-defined diagnoses,[ 7 ] sometimes for many diagnoses in a tightly defined patient social group[ 8 ] (interim results only) and even by a single practitioner looking at his success with 829 consecutive patients.[ 9 ] An outcome study of an individual condition, chronic headache with very positive results for homeopathy,[ 10 ] nicely pointed up the disjunction of RCT results, which have been generally unimpressive with homeopathic treatment of headache, with those of homeopathy in the real world.[ 11 ]
- 1 Walach H, Jonas WB, Lewith G. The role of outcomes research in evaluating complementary and alternative medicine. In: Lewith G, Jonas WB, Walach H, (eds). Clinical Research in Complementary Therapies: Principles, Problems and Solutions. London: Churchill Livingstone; 2002. pp 29–45.
- 2 Walach H. Reinventing the wheel will not make it rounder: controlled trials of homeopathy reconsidered. J Altern Complement Med 2003; 9: 7–13.
- 3 Oberbaum M, Vithoulkas G, van Haselen R, Singer S. Reinventing the wheel? Or the emperor's new clothes. J Altern Complement Med 2003; 9: 613–617.
- 4 Linde K, Clausius N, Ramirez G, et al. Are the clinical effects of homeopathy placebo effects? A meta-analysis of placebo-controlled trials. Lancet 1997; 350: 834–843.
- 5 Cucherat M, et al. Evidence of clinical efficacy of homeopathy. A meta-analysis of clinical trials. Eur J Clin Pharmacol 2000; 56: 27–33.
- 6 Linde K, Scholz M, Ramirez G, et al. Impact of study quality on outcome in placebo-controlled trials of homeopathy. J Clin Epidemiol 1999; 52: 631–636.
- 7 Riley D, Fischer M, Singh B, et al. Homeopathy and conventional medicine: an outcomes study comparing effectiveness in a primary care setting. J Altern Complement Med 2001; 7: 149–159.
- 8 Walach H, Guthlin C. Effects of acupuncture and homeopathy: prospective documentation. Interim results. Br Hom J 2000; 89(suppl 1): S31–S34.
- 9 Sevar R. Audit of outcome in 829 consecutive patients treated with homeopathic medicines. Br Hom J 2000; 89: 178–187.
- 10 Muscari-Tomaioli G, Allegri F, Miali E, et al. Observational study of quality of life in patients with headache receiving homeopathic treatment. Br Hom J 2001; 90: 189–197.
- 11 Whitmarsh T. Editorial Commentary. Cephalalgia 2002; 22: 331–332.
- 12 Van Wassenhoven M, Ives G. An observational study of patients receiving homeopathic treatment. Homp 2004; 93: 3–11.