Hui-Chuan Hsu1,2, Wen-Chiung Chang3,4. 1. Department of Health Care Administration, Asia University, Taichung, Taiwan. 2. Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan. 3. Surveillance and Research Division, Health Promotion Administration, Ministry of Health and Welfare, Taipei, Taiwan. 4. Institute of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.