1. Department of Family Medicine, Yonsei University College of Medicine, Seoul, Korea
2. Department of Family Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
3. The 3rd Air and Missile Defense Brigade, Air & Missile Defense Command, Republic of Korea Air Force, Seoul, Korea
4. Department of Family Medicine, Yongin Severance Hospital, Yonsei University College of Medicine, Yongin, Korea