BHA

44% of randomised controlled trials in homeopathy have reported positive effects; only 8% have been negative.

Evidence summary

homeopathic pillules
Do you need research evidence to back up your request for a homeopathy referral? Download our two page summary of the evidence here. Or look at the list of conditions with positive evidence.

The evidence for homeopathy

There is a growing body of clinical evidence to show that homeopathy has a positive effect.

Randomised controlled trials

The widely accepted method of proving whether or not a medical intervention works is called a randomised controlled trial (RCT). One group of patients, the control group, receive placebo (a “dummy” pill) or standard treatment, and another group of patients receive the medicine being tested. The trial becomes double-blinded when neither the patient nor the practitioner knows which treatment the patient is getting. RCTs are often referred to as the “gold standard” of clinical research.

A total of 156 RCTs in homeopathy (on 75 different medical conditions) have been published in good quality scientific journals. 41% of the RCTs have a balance of positive evidence, 7% have a balance of negative evidence, and 52% have not been conclusively positive or negative. For full details of all these RCTs and more in-depth information on the research in general, visit the research section of the Faculty of Homeopathy's website.

The above figures have similarities to data obtained from an analysis of 1016 systematic reviews of RCTs (and therefore of many more than that number of RCTs in total): 44% of the reviews concluded that the interventions studied were likely to be beneficial (positive), 7% concluded that the interventions were likely to be harmful (negative), and 49% reported that the evidence did not support either benefit or harm (non-conclusive). [El Dib RP, Atallah AN, Andriolo RB (2007). Mapping the Cochrane evidence for decision making in health care. Journal of Evaluation in Clinical Practice; 13:689–692.]

Systematic reviews

The most solid evidence for a treatment comes from critically assessing more than one RCT in a carefully defined way. This is known as a systematic review. Four out of five major systematic reviews of RCTs in homeopathy have concluded (with certain caveats) that homeopathy has an effect greater than placebo. Systematic reviews of RCTs in specific medical areas have presented positive conclusions for homeopathy in seven: childhood diarrhoea, hay fever, influenza treatment, post-operative ileus, respiratory tract infection, rheumatic diseases and vertigo.

For full details of all 156 RCTs and more in-depth information on the research, visit the research section of the Faculty of Homeopathy's website. This includes details of those RCTs that were either negative or non-conclusive.

Difficulties with RCTs
The RCT model of measuring efficacy of a drug poses some challenges for homeopathic research. In homeopathy, treatment is usually tailored to the individual. A homeopathic prescription is based not only on the symptoms of disease in the patient but also on a host of other factors that are particular to that patient, including lifestyle, emotional health, personality, eating habits and medical history. The “efficacy” of an individualised homeopathic intervention is thus a complex blend of the prescribed medicine together with the other facets of the in-depth consultation and integrated health advice provided by the practitioner; under these circumstances, the specific effect of the medicine itself may be difficult to quantify with precision in RCTs.

An alternative research approach, which the majority of researchers have adopted, is the “one drug fit all patients” type of RCT. Such trials are capable of quantifying efficacy of the homeopathic “drug” under investigation, but they may yield results that are of questionable relevance to the practice of homeopathy in the “real world”.

Non-randomised studies

There are other types of study that form part of the evidence base for any medical intervention. Clinical outcome studies record the patient's self-reported response after treatment. Studies of this kind are neither randomised nor controlled. Although they lie near the lower end of the “hierarchy” of research evidence, study designs such as these can reflect how homeopathy is working in practice and indicate where RCT research might be targeted.

The experience of patients
Many patients referred for homeopathic treatment have a complexity of health problems. They may suffer from more than one disease. They could be young children or elderly people. They may be pregnant. None of these sorts of patients would be accepted for a drug trial in conventional medicine, so their reactions to treatment are not reflected in the results of RCTs. The recording of clinical data from everyday practice reflects the experiences of real patients and is becoming an increasingly valued part of evidence-based medicine. View results from the homeopathic hospitals.

There are 20 non-randomised studies that have focused on a particular medical condition. References to these are listed, along with RCTs and systematic reviews, in our document: Clinical research evidence in favour of homeopathy.