Table 6. Multivariate analysis for the factors predicting longer overall survival (Cox regression model) at the time of progression of glioblastoma.

Variables	Hazard ratio	95% CI	p value
Age (<50 yrs vs. ≥50 yrs)	1.326	0.759–1.893	0.352
Surgical extent
(STR+GTR vs. Bx)	2.443	1.261–3.625	0.027
(GTR vs. STR)	1.543	0.885–2.201	0.208
RPA class
(III vs. IV+V)	2.517	1.436–3.598	0.021
(IV vs. V)	1.229	0.704–1.754	0.413
Methylation status of MGMT gene promoter (methylated vs. unmethylated)	1.402	0.963–1.841	0.117
KPS score (≥80 vs. <80)	2.007	1.313–2.701	0.035
ECOG/WHO performance status (0–1 vs. 2–5)	1.321	0.810–1.832	0.143
NANO scale (0–7 vs. 8–23)	3.182	1.993–4.371	0.002

Bx, biopsy; CI, confidence interval; ECOG, Eastern Cooperative Oncology Group; GTR, gross total resection; KPS, Karnofsky Performance Scale; MGMT, O6-methyl guanine DNA methyltransferase; NANO, Neurological Assessment of Neuro-Oncology; RPA, recursive partitioning analysis; STR; subtotal resection; WHO, World Health Organization