Table 3.

Multivariate analysis for event-free survival

Parameter	Chi-square	P	Hazard ratio	95% Confidence interval
Age, y
31-59	5.4	.02	1.51	1.07, 2.13
≥ 60	20.4	< .01	2.65	1.74, 4.05
Philadelphia chromosome	9.4	< .01	1.85	1.25, 2.74
Systemic risk classification (high)	5.5	.02	1.72	1.09, 2.71
Leukocyte count > 30 x 109/L	5.7	.02	1.49	1.07, 2.07
CD20 expression ≥ 20%	5.0	.03	1.42	1.04, 1.93