Evaluation of specific and non-specific effects in homeopathy: feasibility study for a randomised trial

Abstract

Objective: To determine the feasibility, in terms of acceptability to patients, physicians and other staff; data return and statistical power of a study to elucidate the relative contributions of specific and non-specific effects in homeopathic treatment of dermatitis.

Design: Randomised, controlled 4-arm trial, 2 arms double-blind.

Setting: Outpatient clinic, Royal London Homoeopathic Hospital.

Participants: Seventy-five adult patients with dermatitis.

Interventions: Patients were randomly allocated to: 'fast track' open verum homeopathy, 'fast track' double-blind verum homeopathy, 'fast track' double-blind placebo homeopathy or waiting list control.

Main outcome measures: One hundred millimeter visual analogue scale of overall symptom severity; 10 point digital scores of sleep, itching, skin condition; weekly 5-point Likert scale of topical steroid use; Dermatology Life Quality Index at entry and completion.

Results: Recruitment was below target, but the study was acceptable to staff and feasible. Blinded patients were more likely to withdraw (P=0.021, chi2 test). After correction for baseline differences and multiple comparisons, no outcome measure showed statistically significant between group differences. Blindness appeared to have a negative effect, but this was confounded by differential withdrawal.

Conclusions: A definitive trial of this design is unlikely to discriminate the relative contributions of the non-specific and specific effects to the outcome of homeopathic treatment of dermatitis, because of patient preference issues.