1. Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, UK
2. Department of Mathematics and Statistics, Lancaster University, UK
3. Department of Biostatistics, Institut de Recherches Internationales Servier (IRIS), France
4. Dipartimento di Scienze Matematiche (DISMA) Giuseppe Luigi Lagrange, Politecnico di Torino, Italy
5. MRC Biostatistics Unit, University of Cambridge, UK