1. Department of Internal Medicine, Okayama Saiseikai General Hospital, Okayama City, Japan
2. Department of Patient Support Center, Okayama Saiseikai General Hospital, Okayama City, Japan
3. Health Screening Center, Okayama Saiseikai Health Checkup Center, Okayama City, Japan
4. Department of Internal Medicine, Saiseikai Kibi Hospital, Okayama City, Japan