Table 6.

Multivariate analysis of factors affecting overall survival

	Relative risk of death (95% CI)	P overall
Main effect		< .001†
1989-1994	1.00 (reference)
1995-2000	0.83 (0.69-1.01)	.05
2001-2005*
≤ 6 mo after transplantation	0.41 (0.32-0.53)	< .001
> 6 mo after transplantation	0.98 (0.76-1.26)	.86
Other significant factors
Age, continuous	1.01 (1.00-1.02)	.04
Time from diagnosis to transplant
≤ 24 mo	1.00 (reference)
> 24 mo	1.24 (1.06-1.45)	.01
Donor
HLA-identical sibling	1.00 (reference)
Others	1.79 (1.52-2.11)	< .001

^*Different relative risks in early and late time periods after transplantation indicates a covariate with nonproportional hazards (P < .001).

^†Three degrees of freedom.