1. Department of Biostatistics, Korea University College of Medicine, Seoul 02842, Republic of Korea
2. Medical Science Research Center, Korea University Ansan Hospital, Ansan 15355, Republic of Korea
3. Department of Otorhinolaryngology-Head and Neck Surgery, Ansan Hospital, Korea University College of Medicine, Ansan 15355, Republic of Korea
4. Department of Medical Informatics, Korea University College of Medicine, Seoul 02842, Republic of Korea