1. Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
2. Department of Internal Medicine, School of Medicine, Korea University, Ansan 02841, Republic of Korea
3. Department of Biomedical Science and Technology, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
4. Department of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea