1. University of Pittsburgh, Division of Gastroenterology, Hepatology and Nutrition, Pittsburgh, Pennsylvania, USA;
2. Center for Health Equity Research and Promotion, VA Veteran Affairs Pittsburgh Healthcare System, Pennsylvania, USA;
3. Pharmacy Benefits Management, Veterans Integrated Service Network 8, Bay Pines, Florida, USA;
4. Pharmacy Benefits Management, Veterans Integrated Service Network 20, Vancouver, Washington, USA;
5. Gastroenterology Section, VA Long Beach Healthcare System, Long Beach, California, USA;
6. Division of Gastroenterology, Hepatology and Nutrition, Virginia Commonwealth University Medical Center, Richmond, Virginia, USA;
7. GI Section, Central Virginia Veterans Healthcare System, Richmond, Virginia, USA.