1. Department of Palliative Medicine, Takeda General Hospital, Aizuwakamatsu, Japan
2. Department of Palliative Medicine, Tohoku University School of Medicine, Sendai, Japan
3. Department of Family Medicine, Dongguk University Ilsan Hospital, Goyang-si, South Korea
4. Department of Medicine, Dongguk University Medical School, Seoul, South Korea
5. Department of Family Medicine and Hospice-Palliative Care Team, Chungnam National University Hospital and School of Medicine, Chungnam National University, Daejeon, South Korea