1 Division of Gastroenterology and Hepatology, Perelman School of Medicine, University of Pennsylvania, and, Department of Medicine, Corporal Michael J. Crescenz VA Medical Center, and, Leonard David Institute of Health Economics, Perelman School of Medicine, University of Pennsylvania, and, Center for Clinical Epidemiology and Biostatistics, Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
2 Division of Gastroenterology and Hepatology, Perelman School of Medicine, University of Pennsylvania, and, Department of Medicine, Corporal Michael J. Crescenz VA Medical Center, and, Leonard David Institute of Health Economics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.
3 Division of Gastroenterology and Hepatology, Perelman School of Medicine, University of Pennsylvania, and, Department of Medicine, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, Pennsylvania.