1. Department of Plastic and Reconstructive Surgery, Haukeland University Hospital, Bergen, Norway;
2. Department of Clinical Medicine, University of Bergen, Bergen, Norway;
3. Department of Plastic and Reconstructive Surgery, Helsinki University Hospital, Helsinki, Finland;
4. Department of Plastic and Reconstructive Surgery, Herlev-Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark;
5. Department of Plastic and Reconstructive Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden;
6. Department of Clinical Sciences Malmö, Lund University, Lund, Sweden