1. Department of Physical Medicine and Rehabilitation, Japanese Red Cross Ashikaga Hospital, Ashikaga, Japan
2. Dysphagia Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
3. Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
4. Department of Internal Medicine, Japanese Red Cross Ashikaga Hospital, Ashikaga, Japan