1Centre for Child Health, Bristol Medical School: Population Health Sciences, University of Bristol, Bristol, UK
2Bristol Medical School: Population Health Sciences, University of Bristol, Bristol, UK
3Bristol Randomised Trials Collaboration, University of Bristol, Bristol, UK
4Bristol Medical School: Population Health Sciences, Oakfield House, Bristol, UK
5Department for Health, University of Bath, Bath, UK
6Department for Medical Psychology, University Medical Centres Amsterdam, University of Amsterdam, Amsterdam, The Netherlands
7Department of Paediatrics, Wilhelmina Children’s Hospital, University Medical Centre, Utrecht, The Netherlands
8Radboud University Medical Center, Nijmegen, The Netherlands