1. Department of Behavioural Science and Health, University College London , London , UK
2. SPECTRUM Consortium , London , UK
3. Institute of Health Informatics, University College London , London , UK
4. UCL Institute of Ophthalmology, University College London , London , UK
5. Centre for Emerging, Endemic and Exotic Diseases, Royal Veterinary College , London , UK
6. Weight Control and Diabetes Research Center, The Miriam Hospital , Providence, RI , USA
7. Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University , Providence, RI , USA
8. Behavioural and Implementation Science Research Group, School of Health Sciences, University of East Anglia , Norwich , UK