1. Department of Preventive Medicine, Armed Forces Medical Command, Seongnam, Korea.
2. Preventive Medicine Program, Graduate School of Public Health, Seoul National University, Seoul, Korea.
3. Department of Preventive Medicine, Gachon University College of Medicine, Incheon, Korea.
4. Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea.
5. Department of Psychiatry, Armed Forces Capital Hospital, Seongnam, Korea.
6. Geumcheon Kidari Mental Clinic, Seoul, Korea.
7. Department of Psychiatry, Armed Forces Guri Hospital, Armed Forces Medical Command, Guri, Korea.
8. Department of Psychiatry, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.