Table 2. Univariate cox regression analysisof prognostic factors for overall survival rates of astrocytoma patients.

Variety	Classification	Death cases/Total cases	Median survival time	1 year/3 year overall survival	p	HR(95%CI)
Total	/	147/160	11	28.8%/6.6%	/	/
Sex	Male	80/88	11	26.1%/6.8%	0.769	1
	Female	67/72	11	31.9%/6.3%		1.05(0.76-1.44)
Age	< 40years	58/66	11	31.8%/8.6%	0.186	1
	≥40years	89/94	10	26.6%/-		1.23(0.88-1.71)
WHO classification extent of surgical resection	I-II grade	86/96	11	28.1%/	0.612	1
	III grade	61/64	11	29.7%/3.9%		1.08(0.78-1.50)
	Not all resection	98/111	9	16.3%/-	0.003	1
	Total resection	49/49	11	34.2%/9.6%		0.61(0.43-0.88)
Radiotherapy	No	11/14	12	46.2%/-	0.334	1
	Conformal radiotherapy	38/41	9	14.6%/8.8%		1.48(0.75-2.91)
	Gamma knife	99/106	11	32.1%/-		1.18(0.63-2.21)
Chemotherapy	No	96/102	9	23.5%/-	0.029	1
	Yes	51/58	12	37.9%/11.4%		0.71(0.49-0.99)

p<0.05 indicates statistical significance; HR: hazard ratios; CI: confidence interval.