1. Centre for Academic Primary Care, National Institute for Health Research School for Primary Care Research, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
2. Bristol Randomised Trials Collaboration, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
3. National Institute for Health Research School for Primary Care Research, Centre for Primary Care, Division of Population of Health, Health Services Research and Primary Care, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
4. Institute of Health and Wellbeing, University of Glasgow, Glasgow, UK
5. Population Health Sciences Division, School of Medicine, University of Dundee, Dundee, UK
6. Bristol Clinical Commissioning Group, Bristol, UK
7. Royal College of General Practitioners, London, UK