Table 3.

Cox proportional hazards model of overall survival by the covariants identified as significant or near-significant on univariate analysis.

Covariant	p-Value
ECOG 0 or 1 vs. ≥2	0.0001
Controlled vs. uncontrolled extracranial disease	0.001
Multiple GKRS sessions vs. one GKRS session	0.003
Prior metastasectomy vs. no prior metastasectomy	0.09
Breast vs. all other histologies	0.11
Less than 4 metastases vs. ≥4 metastases	0.38
RPA Stage I vs. RPA ≥II	0.41
Commercial insurance or Medicare vs. Medicaid or uninsured	0.49
Prior chemotherapy vs. no prior chemotherapy	0.88

GKRS, Gamma Knife^® Radiosurgery; RPA, recursive partitioning analysis.