1. Division of Gastroenterology, Department of Medicine, Hepatology and Nutrition, School of Medicine, Pittsburgh, Pennsylvania, USA
2. Division of Cancer Control and Population Sciences, UPMC Hillman Cancer Center, Pittsburgh, Pennsylvania, USA
3. Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
4. Department of Epidemiology, School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
5. Department of Surgery, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA