1. School of Mathematics, University of Bristol, Bristol, UK
2. Biostatistics and Data Sciences, Boehringer Ingelheim Pharmaceuticals Inc, Ridgefield, Connecticut, USA
3. Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
4. Biostatistics+Data Sciences Corp, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany