1. Departments of Endocrinology and Metabolic Diseases (M.J.E.W., N.R.B., A.M.P., F.R., J.W.A.S., J.A.R.), Leiden University Medical Center, 2300 RC Leiden, The Netherlands
2. Department of Gastroenterology and Hepatology (M.C., R.J.F.F.-B.), Vrije Universiteit Medical Center, 1081 HV Amsterdam, The Netherlands
3. Gastroenterology and Hepatology (D.W.H.), Leiden University Medical Center, 2300 RC Leiden, The Netherlands