1. Division of Hematology & Oncology, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
2. Harvard Medical School, Boston, Massachusetts, USA
3. Department of Statistics, Massachusetts General Hospital, Boston, Massachusetts, USA
4. Department of Psychiatry, Brigham and Women's Hospital, Boston, Massachusetts, USA
5. Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, USA
6. The Mongan Institute and the Division of Palliative Care and Geriatric Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA