1. Department of Palliative Medicine, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
2. Department of Palliative Medicine, National Cancer Center Hospital, Tokyo, Japan
3. Center for Palliative and Supportive Care, University of Tsukuba Hospital, Tsukuba, Japan
4. Department of Psychosomatic Internal Medicine, National Hospital Organization Kinki-Chuo Chest Medical Center, Sakai, Japan
5. Palliative Care Center, Cancer Center, Kindai University Hospital, Osaka, Japan
6. Faculty of Health, University of Technology Sydney, Australia
7. Division of Medical Oncology, Sasaki Foundation Kyoundo Hospital, Tokyo, Japan
8. Department of Palliative Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
9. Department of Biostatistics, JORTC Data Center, Tokyo, Japan
10. Division of Biostatistics, Tohoku University Graduate School of Medicine, Sendai, Japan
11. Department of Palliative Medicine, Saitama Medical University, Saitama, Japan