Randomised clinical trials (RCTs) are regarded as a ‘gold standard’ method for assessing the effects of treatments. But how did they come to be accepted? Here Sir Iain Chalmers describes an often overlooked MRC trial of a potential treatment for the common cold, and explains the role it played on the road to randomisation.
When people look back on the history of clinical trials, the MRC trial of streptomycin for pulmonary tuberculosis reported in 1948 tends to receive a lot of attention. But there’s an earlier MRC trial that helped to develop methods to ensure that there is no bias in how patients are allocated to particular treatment groups, to ensure that ‘like is compared with like’. And, unlike the streptomycin trial, this earlier trial used placebos to reduce bias in measuring treatment outcomes.
The trial had been prompted by conflicting reports about possible beneficial effects on the common cold of patulin, a fungal toxin often found in rotting apples. Between 18 January and 11 April 1944, volunteers at three London units of the General Post Office, along with four Royal Ordnance factories, and seven other factories participated in the MRC’s first well-controlled multicentre clinical trial. Read more