Baseline characteristics of the cohorts
| Training cohort | Internal validation cohort | P value* | External validation cohort | P value† | |
| n=643 | n=271 | n=502 | |||
| Age, years, mean (SD) | 66.6 (11.9) | 66.4 (11.3) | 0.807 | 65.1 (12.6) | 0.035 |
| Men, n (%) | 394 (61.3) | 172 (63.5) | 0.533 | 305 (60.8) | 0.858 |
| Hypertension, n (%) | 428 (66.6) | 171 (63.1) | 0.314 | 312 (62.2) | 0.121 |
| Diabetes, n (%) | 111 (17.3) | 51 (18.8) | 0.574 | 95 (18.9) | 0.468 |
| Atrial fibrillation, n (%) | 297 (46.2) | 137 (50.6) | 0.228 | 207 (41.2) | 0.1 |
| Baseline NIHSS score, median (IQR) | 16 (13–20) | 15 (12–19) | 0.231 | 16 (12–21) | 0.286 |
| Baseline ASPECT score, median (IQR) | 9 (8–10) | 9 (7–10) | 0.769 | 9 (8–10) | 0.001 |
| IVT, n (%) | 149 (23.2) | 54 (19.9) | 0.281 | 164 (32.7) | <0.001 |
| TOAST classification, n (%) | 0.262 | <0.001 | |||
| Atherosclerotic | 222 (34.5) | 86 (31.7) | 224 (44.6) | ||
| Cardioembolic | 337 (52.4) | 157 (57.9) | 248 (49.4) | ||
| Others | 84 (13.1) | 28 (10.3) | 30 (6.0) | ||
| OTP, min, median (IQR) | 279 (218–350) | 292 (215–360) | 0.586 | 280 (205–360) | 0.535 |
| OTR, min, median (IQR) | 359 (289–446) | 368 (300–455) | 0.241 | 395 (307–495) | 0.001 |
| Collateral status, n (%) | 0.256 | 0.254 | |||
| Poor | 351 (54.6) | 159 (58.7) | 257 (51.2) | ||
| Good | 292 (45.4) | 112 (41.3) | 245 (48.8) | ||
| First treatment, n (%) | 0.930 | <0.001 | |||
| Stent retriever | 427 (66.4) | 177 (65.3) | 469 (93.4) | ||
| Contact aspiration | 133 (20.7) | 59 (21.8) | 0 | ||
| Angioplasty | 82 (12.8) | 35 (12.9) | 33 (6.6) | ||
| Tandem, n (%) | 69 (10.7) | 36 (13.3) | 0.269 | 44 (8.8) | 0.069 |
| Occlusion site, n (%) | 0.471 | 0.541 | |||
| MCA | 356 (55.4) | 143 (52.8) | 215 (42.8) | ||
| ICA | 287 (44.6) | 128 (47.2) | 287 (57.2) | ||
| mTICI 2b-3, n (%) | 532 (82.7) | 203 (74.9) | 0.006 | 427 (85.1) | 0.290 |
| MBE, n (%) | 135 (21.0) | 57 (21.0) | 0.990 | 130 (25.9) | 0.051 |
| FBG, mmol/L, mean (SD) | 7.17 (3.18) | 7.46 (7.10) | 0.411 | 7.82 (3.15) | 0.001 |
| LDL, mmol/L, mean (SD) | 2.36 (0.84) | 2.30 (0.89) | 0.307 | 2.57 (0.86) | <0.001 |
| BUN, mmol/L, mean (SD) | 6.22 (2.83) | 7.70 (26.6) | 0.217 | 6.25 (4.29) | 0.232 |
| Cr, μmol/L, mean (SD) | 83.3 (40.40) | 80.38 (37.93) | 0.268 | 80.47 (38.26) | 0.264 |
| sICH, n (%) | 58 (9) | 39 (14.4) | 0.016 |
*P indicates training cohort compared with internal validation cohort.
†P indicates training cohort compared with external validation cohort.
ASPECT, Alberta Stroke Program Early CT; BUN, blood urea nitrogen; Cr, creatinine; FBG, fasting blood glucose; ICA, internal carotid artery; IVT, intravenous thrombolysis; LDL, low-density lipoprotein; MBE, malignant brain edema; MCA, middle cerebral artery; mTICI, modified Thrombolysis In Cerebral Infarction; NIHSS, National Institutes of Health Stroke Scale; OTP, symptom onset to groin puncture time; OTR, time from stroke onset to recanalization; sICH, symptomatic intracranial hemorrhage; TOAST, the Trial of ORG 10172 in Acute Stroke Treatment.