1. Epidemiology and Public Health, School of Health and Related Research, University of Sheffield , Sheffield , UK
2. School of Health and Related Research, University of Sheffield , UK
3. Clinical Decision Science, School of Health and Related Research, University of Sheffield , UK
4. Department of Landscape Architecture, University of Sheffield , Sheffield , UK
5. Medical Statistics and Clinical Trials, School of Health and Related Research, University of Sheffield , Sheffield , UK
6. Sheffield Vascular Institute, Sheffield Teaching Hospitals NHS Foundation Trust , UK