作者单位:Stanford Univ, Dept Med, Palliat Care, Stanford, CA 94305 USA[1]Stanford Univ, Dept Med, Quantitat Sci Unit, Stanford, CA 94305 USA[2]Kaiser Permanente, Dept Hematol Oncol, Santa Clara, CA USA[3]Stanford Univ, Dept Med Blood & Marrow Transplantat, Stanford, CA 94305 USA[4]