1 General Surgery Department, University of Vermont Medical Center, Burlington, Vermont; Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
2 Department of Internal Medicine & Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
3 Faculty of Medicine, University of Iceland, Reykjavik, Iceland; Department of Gastroenterology and Hepatology, Landspitali University Hospital, Reykjavik, Iceland.