John Saltzman, MD, is professor of medicine, part-time at Harvard Medical School, long-term director of Endoscopy at the Brigham and Women's Hospital; and the director of the Brigham and Women's Hospital Advanced Endoscopy Fellowship Program in Boston, MA.

Richard S. Blumberg, MD, is professor of medicine, Harvard Medical School; and chief of the Division of Gastroenterology, Hepatology and Endoscopy at Brigham and Women's Hospital in Boston, MA.

Norton J. Greenberger, MD, was an attending physician and clinical professor of medicine at Harvard Medical School. He was a past president of the American Gastroenterological Association, the American College of Physicians, the Central Society for Clinical Research, and the Association of Professors of Medicine. Greenberger was the author or co-author of numerous original publications, chapters in major medical texts and textbooks.