1. Health Psychology Section, Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, Guy's Hospital King's College London London UK
2. Warwick Clinical Trials Unit, Warwick Medical School University of Warwick Coventry UK
3. Sydney Medical School, Westmead Clinical School University of Sydney Sydney New South Wales Australia
4. Department of Women and Children's Health, Faculty of Life Sciences and Medicine, St Thomas' Hospital King's College London London UK