1. University of Arkansas for Medical Sciences (UAMS), College of Medicine, Little Rock, AR 72205, USA
2. Department of Otorhinolaryngology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
3. Department of Biostatistics, UAMS, Little Rock, AR 72205, USA
4. Department of Otolaryngology-Head and Neck Surgery, UAMS, 4301 W. Markham Street No. 543, Little Rock, AR 72205, USA