1. University of Groningen, University Medical Center Groningen, Department of Plastic Surgery, Groningen, the Netherlands
2. University of Groningen, University Medical Center Groningen, Department of General Practice and Elderly Care Medicine, Academic General Practitioner Development Network, Groningen, the Netherlands
3. University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Botnar Research Centre, Oxford, UK
4. University of Oxford, Department of Plastic and Reconstructive Surgery, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, UK
5. Eindhoven University of Technology, Department of Mathematics and Computer Science, Eindhoven, the Netherlands