Table 2.

The Pearson’s chi-square test of potential risk factors for atypical and anaplastic meningiomas

Characteristic	No. of atypical and anaplastic	P value
Gender
Male	77	< 0.001
Female	114
Age (years)
< 65	161	0.711
≥ 65	30
Tumor location
Skull base	36	< 0.001
Non-skull base	155
Cerebral convexity	122	< 0.001
Non-cerebral convexity	69
Falx/sagittal sinus	9	0.936
Non-falx/sagittal sinus	182
Intraventricular	8	0.907
Non-intraventricular	183