1. School of Public Health, Seoul National University, South Korea,
2. Division of Gastroenterology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea,
3. Drug Price Management Council, Health Insurance Review Agency, Seoul, South Korea,
4. School of Public Health, University of North Carolina, Chapel Hill, USA and
5. Glaxo Wellcome Research and Development, Middlesex, UK