1. Division of Surgery, Department of Clinical and Experimental Medicine, Faulty of Health Sciences, Linköping University, Department of Surgery, County Council of Östergötland, Linköping, Sweden
2. Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Stockholm, Sweden
3. Division of Clinical Epidemiology, Department of Medicine Solna, Stockholm, Sweden
4. Department of Molecular Medicine and Surgery, Stockholm, Sweden
5. Centre for Digestive Disease, Division of Coloproctology, Karolinska University Hospital, Stockholm, Sweden
6. Department of Gastroenterology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
7. Department Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
8. Department of Paediatrics, Örebro University Hospital, Örebro University, Örebro, Sweden
9. Division of Epidemiology and Public Health, School of Medicine, University of Nottingham, Nottingham, UK
10. Department of Medicine, Columbia University College of Physicians and Surgeons, New York, USA
11. Department of Paediatric Gastroenterology and Nutrition, Sachs' Children and Youth Hospital, Stockholm, Sweden