1. Medizinisch-Diagnostische Laboratorium West OG; Vienna Austria
2. Division of Gastroenterology and Hepatology; Mayo Clinic; Rochester MN USA
3. Division of Gastroenterology; McMaster University; Hamilton ON Canada
4. Division of Biomedical Statistics and Informatics; Mayo Clinic; Rochester MN USA
5. Faculty of Health and Medicine; University of Newcastle; New Lambton NSW Australia