1. Division of Gastroenterology & Hepatology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
2. Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
3. Vatche & Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California
4. Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, Maryland
5. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
6. Division of Gastrointestinal and Liver Diseases, Department of Medicine, Keck School of Medicine of the University of Southern California, Los Angeles
7. Division of Gastroenterology, Department of Medicine, University of California San Francisco School of Medicine, San Francisco