By the end of 2014, 189 randomised controlled trials of homeopathy on 100 different medical conditions had been published in peer-reviewed journals1. Of these, 104 papers were placebo-controlled and were eligible for detailed review:
41% were positive (43 trials) – finding that homeopathy was effective5% were negative (5 trials) – finding that homeopathy was ineffective54% were inconclusive (56 trials)
How does this compare with evidence for conventional medicine?
An analysis of 1016 systematic reviews of RCTs of conventional medicine had strikingly similar findings2:
44% were positive – the treatments were likely to be beneficial7% were negative – the treatments were likely to be harmful49% were inconclusive – the evidence did not support either benefit or harm.
Although the percentages of positive, negative and inconclusive results are similar in homeopathy and conventional medicine, it is important to recognise a vast difference in the quantity of research carried out; chart A represents 189 individual trials on homeopathy, whereas chart B represents 1016 reviews on conventional medicine, each analysing multiple trials.
This highlights the need for more research in homeopathy, particularly large-scale high quality repetitions of the most promising positive studies.
The difference in quantity is also not surprising when one considers the tiny amounts of funding made available for research into ‘complementary and alternative medicine’ (CAM). For example, in the UK only 0.0085% of the total medical research budget is spent on CAM, of which homeopathy is only one example3.