PHASES score
| Items | Points |
|---|---|
| (P) Population | |
| North American, European (except Finnish) | 0 |
| Japanese | 3 |
| Finnish | 5 |
| (H) Hypertension | |
| No | 0 |
| Yes | 1 |
| (A) Age | |
| < 70 years | 0 |
| ≥ 70 years | 1 |
| (S) Size of aneurysm | |
| < 7.0 mm | 0 |
| 7.0–9.9 mm | 3 |
| 10.0–19.9 mm | 6 |
| ≥ 20 mm | 10 |
| (E) Earlier SAH from another aneurysm | |
| No | 0 |
| Yes | 1 |
| (S) Site of aneurysm | |
| Internal carotid artery | 0 |
| Middle cerebral artery | 2 |
| Anterior cerebral artery/posterior communicating artery/posterior circulation | 4 |
| Risk of rupture of intracranial aneurysms in 5 years | |
| 0.4% | ≤ 2 |
| 0.7% | 3 |
| 0.9% | 4 |
| 1.3% | 5 |
| 1.7% | 6 |
| 2.4% | 7 |
| 3.2% | 8 |
| 4.3% | 9 |
| 5.3% | 10 |
| 7.2% | 11 |
| 17.8% | ≥ 12 |
SAH: subarachnoid hemorrhage; mm: millimeters; PHASES: population, hypertension, age, size of aneurysm, earlier SAH from another aneurysm, site of aneurysm