| HMCAS-D (n = 831) | HMCAS-P (n = 788) | p Value | |
| Age (years) (median (IQR)) | 67 (58–75) | 69 (59–76) | 0.03 |
| Men (n (%)) | 467 (56.2) | 466 (59.1) | 0.3 |
| Weight (kg) (mean (SD)) | 76.6 (13.8) | 77.0 (14.5) | 0.6 |
| Stroke risk factors | |||
| No of risk factors (median (IQR)) | 2 (1–2) | 2 (1–2) | 0.7 |
| Hypertension (n (%)) | 468 (56.3) | 478 (60.7) | 0.2 |
| Diabetes (n (%)) | 116 (14.0) | 114 (14.5) | 0.9 |
| Hyperlipidaemia (n (%)) | 253 (30.5) | 245 (31.1) | 0.8 |
| Smoking, current and previous (n (%)) | 326 (39.3) | 289 (36.7) | 0.3 |
| History of stroke (n (%)) | 84 (10.1) | 66 (8.4) | 0.2 |
| Atrial fibrillation (n (%)) | 229 (27.6) | 234 (29.7) | 0.6 |
| Congestive heart failure (n (%)) | 66 (8.0) | 59 (7.5) | 0.4 |
| Pre-existing disability = mRS 2–5 at baseline (n (%)) | 54 (6.5) | 63 (8.0) | 0.5 |
| Baseline treatment | |||
| Aspirin (n (%)) | 234 (28.2) | 226 (28.7) | 0.8 |
| Dipyridamol (n (%)) | 8 (1.0) | 10 (1.3) | 0.7 |
| Clopidogrel (n (%)) | 33 (4.0) | 26 (3.3) | 0.9 |
| Other antiplatelet drug (n (%)) | 10 (1.2) | 12 (1.5) | 0.5 |
| Anticoagulant IV, therapeutic dose (n (%)) | 4 (0.5) | 3 (0.4) | 0.6 |
| Anticoagulant IV, prophylactic dose (n (%)) | 23 (2.8) | 14 (1.8) | 0.1 |
| Anticoagulant oral (n (%)) | 13 (1.6) | 9 (1.1) | 0.4 |
| Antihypertensive IV (n (%)) | 42 (5.1) | 49 (6.2) | 0.2 |
| Antihypertensive oral (n (%)) | 341 (40.1) | 365 (46.3) | 0.01 |
| Time period | |||
| Onset to treatment time (min) (median (IQR)) | 135 (105–163) | 140 (110–165) | 0.1 |
| Onset to imaging time (min) (median (IQR))) | 89 (67–115) | 90 (67–120) | 0.2 |
| Onset to hospital time (min) (median (IQR)) | 63 (44–90) | 63 (44–90) | 0.9 |
| Admission data | |||
| Admission plasma cholesterol (mmol/l) (mean (SD)) | 7.8 (3.4) | 7.9 (3.4) | 0.7 |
| Admission plasma glucose (mmol/l) (mean (SD)) | 7.1 (3.1) | 7.1 (2.4) | 0.9 |
| NIHSS score on admission (median (IQR)) | 16 (12–20) | 17 (14–20) | <0.001 |
| Systolic blood pressure (mm Hg) (mean (SD)) | 147.1 (20.7) | 148.7 (22.0) | 0.3 |
| Diastolic blood pressure (mm Hg) (mean (SD)) | 81.6 (12.7) | 80.9 (13.4) | 0.4 |
| Presence of infarct on admission CT/MRI scan (n (%)) | 216 (26.0) | 256 (32.5) | 0.001 |
HMCAS-D, hyperdense middle cerebral artery sign, disappearance; HMCAS-P, hyperdense middle cerebral artery sign, persistence; IV, intravenous; mRS, median Rankin Scale Score; NIHSS, National Institute of Health Stroke Scale.