A radical note to end the conference: forget your standalone RCT, just publish the updated meta-analysis. Or, less provocatively, place the meta-analysis center-stage in the study publication and include the RCT results later or publish them on the internet.

Alex Sutton, a medical statistician from the University of Leicester, argued that greater attention should be paid to previous research, notably meta-analyses, when designing a new RCT. The statistics in his argument are complex, but they involve working out, for example, the sample size required in the new study if the findings are to add meaningfully to existing knowledge. One possible, and controversial, consequence of this argument could be that several smaller studies prove more useful than one or two large studies.

Sutton also advocated making better use of existing data before deciding to undertake a new RCT. ‘Mixed treatment comparisons’ are the new fashion, he explained. This method enables researchers to compare