1. Department of Emergency Medicine, School of Medicine, Kyungpook National University, Daegu, Korea.
2. The Korean Association of Cardiopulmonary Resuscitation, Seoul, Korea.
3. Department of Emergency Medicine, Wonju College of Medicine, Yonsei University, Wonju, Korea.
4. National Emergency Medical Center, Seoul, Korea.
5. Department of Emergency Medicine, Soonchunhyang University Seoul Hospital, Seoul, Korea.