Table 6 Variable assignment

Age

 < 58 Y = 0, ≥ 58 Y = 1

History of hypertension

No = 0, Yes = 1

Preoperative intracranial hematoma volume

 < 20 mL = 0, ≥ 20 mL = 1

Aneurysm size

 < 8 mm = 0, ≥ 8 mm = 1

Preoperative Hunt–Hess grade

Grade I = 1, grade II = 2, grade III = 3, grade IV = 4

Later surgery

Within 24 h = 1, within 48 h = 2, within 72 h = 3

Postoperative complications

No = 0, Yes = 1

NIHSS score

 < 13 points = 0, ≥ 13 points = 1