1. Department of Surgery; Institute of Clinical Sciences, Sahlgrenska Academy, the University of Gothenburg; Gothenburg Sweden
2. Department of Research; Royal College of Surgeons of England, Lincoln's Inn Fields; London UK
3. Department of Pediatrics; Institute of Clinical Sciences, Sahlgrenska Academy, the University of Gothenburg; Gothenburg Sweden
4. Childhood Obesity Unit; Skåne University Hospital; Malmö Sweden
5. Department of Clinical Science; Intervention and Technology (CLINTEC), Karolinska Institute, Karolinska University Hospital; Stockholm Sweden