1 Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan. Electronic address: chenlin@ntu.edu.tw.
2 Division of Gastroenterology and Hepatology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Clinical Medicine, National Taiwan, University College of Medicine, Taipei, Taiwan.
3 Division of Thoracic Surgery, Department of Surgery, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
4 Department of Pediatrics, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan.