1. Mental Health and Addiction Research Group, Department of Health Sciences, University of York, York, UK
2. York Trials Unit, Department of Health Sciences, University of York, York, UK
3. Epidemiology and Cancer Statistics Group, Department of Health Sciences, University of York, York, UK
4. Northern Lincolnshire and Goole NHS Foundation Trust, Scunthorpe General Hospital, Scunthorpe, UK
5. Leeds and York Partnership NHS Foundation Trust, Bootham Park Hospital, York, UK
6. Department of Health Sciences, University of York, York, UK
7. Hull York Medical School, York, UK
8. Patient and public involvement representative, York, UK
9. Harrogate and District NHS Foundation Trust, Harrogate District Hospital, Harrogate, UK