1. University Hospital Wishaw, 50 Netherton Street, Wishaw, ML2 0DP, UK
2. Usher Institute of Population Health Sciences, Old Medical School, Teviot Place, Edinburgh, EH8 9AG, UK
3. Health Economics & Health Technology Assessment, Institute of Health and Wellbeing, University of Glasgow, 1 Lilybank Gardens, Glasgow G12 8RZ, UK
4. University Hospital Hairmyres, 218 Eaglesham Rd, East Kilbride, G75 8RG, UK