1. Institute of Applied Health Sciences, University of Aberdeen, United Kingdom
2. Now affiliated with the Department of Orthodontics, Liverpool University Hospitals NHS Foundation Trust, United Kingdom
3. Institute of Dentistry, University of Aberdeen, United Kingdom
4. Liverpool Centre for Cardiovascular Science at University of Liverpool, Liverpool John Moores University and Liverpool Heart & Chest Hospital, Liverpool, United Kingdom
5. Danish Center for Clinical Health Services Research, Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
6. Department of Public Health, Policy and Systems, Institute of Population Health, University of Liverpool, United Kingdom
7. General Dental Practitioner, Aesthetique Dental Care, Leeds, United Kingdom