1. Division of General Internal Medicine, Department of Internal Medicine, St. Marianna University School of Medicine, Kanagawa, Japan
2. Division of General Internal Medicine, Department of Internal Medicine, Kawasaki Municipal Tama Hospital, Kanagawa, Japan
3. Department of Biomedical Informatics, University of Pittsburgh, Pennsylvania, USA
4. Department of Behavioral and Community Health Sciences, University of Pittsburgh Graduate School of Public Health, Pennsylvania, USA