Table 1 Patient characteristics
From: Weather conditions associated with subarachnoid hemorrhage: a multicenter case-crossover study
| Â | No | % |
|---|---|---|
Overall population | 791 | Â |
 Woman | 496 | 63 |
 Men | 295 | 37 |
Age | ||
 Young (< 60) | 522 | 66 |
 Old (≥ 60) | 269 | 34 |
Etiology | ||
 Aneurysmal | 568 | 72 |
 Non-aneurysmal / unknown | 223 | 28 |
Aneurysm size | ||
  < 7 mm | 219 | 28 |
  ≥ 7 mm | 209 | 26 |
 Undetermined | 363 | 46 |
WFNS | ||
 1–2 | 494 | 62 |
 3–5 | 297 | 38 |
Fisher grading | ||
 1–3 (no intracerebral or intraventricular clots) | 420 | 53 |
 4 (intracerebral or intraventricular clots) | 371 | 47 |