1. Department of Biostatistics, University of Liverpool, Liverpool, UK
2. Medicines for Children Research Network Clinical Trials Unit, University of Liverpool, Liverpool, UK
3. Bristol Randomised Trials Collaboration Unit, University of Bristol, Bristol, UK
4. Centre for Population Health Sciences, Edinburgh University, Edinburgh, UK
5. Centre for Healthcare Randomised Trials (CHaRT), University of Aberdeen, Aberdeen, UK
6. MRC Clinical Trials Unit, University College London, London, UK
7. London Hub for Trials Methodology Research, University College London, London, UK