1. Centre for Biostatistics, Institute of Population Health, University of Manchester and Manchester Academic Health Science Centre, Manchester, UK
2. Medical Research Council North West Hub for Trials Methodology Research, UK
3. Department of Biostatistics, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
4. Institute of Brain, Behaviour and Mental Health, University of Manchester and Manchester Academic Health Science Centre, Manchester, UK
5. Medical Research Council Biostatistics Unit, University of Cambridge, Cambridge, UK