1. Department of Health Policy Management, Graduate School of Public Health, Yonsei University, Seoul, Korea.
2. Institute of Health Services Research, Yonsei University, Seoul, Korea.
3. Department of Public Health, Graduate School, Yonsei University, Seoul, Korea.
4. Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea.
5. Department of Policy Analysis and Management, College of Human Ecology, Cornell University, Ithaca, NY, USA.