1 Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, California, United States; Trinity College of Arts and Sciences, Duke University, Durham, North Carolina, United States.
2 Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, California, United States.
3 Division of Gastroenterology and Hepatology, Stanford University Medical Center, Palo Alto, California, United States; Department of Epidemiology and Population Health, Stanford University School of Medicine, Palo Alto, California, United States. Electronic address: mindiehn@stanford.edu.