1. Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
2. Division of Gastroenterology, University of Massachusetts, Department of Medicine, Amherst, Massachusetts, USA
3. Department of Medicine, Meharry Medical College, Nashville, Tennessee, USA
4. Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA