1. Department of Palliative, Rehabilitation and Integrative Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas.
2. Division of Geriatrics and Palliative Medicine, The University of Texas Health Science Center at Houston, McGovern Medical School, Harris Health System, Lyndon B. Johnson Hospital, Houston, Texas.
3. Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas.