Diagnostic performance statistics for LVO stroke (ICA, M1, M2 or basilar occlusions) including standard and alternative scale thresholds that meet PPV and NPV goals
| LVO stroke | PPV % (95% CI) | NPV % (95% CI) | Sensitivity % (95% CI) | Specificity % (95% CI) | PLR (95% CI) | NLR (95% CI) |
| Standard thresholds | ||||||
| AAW + | 24 (16 to 34) | 93 (86 to 98) | 79 (60 to 92) | 53 (45 to 61) | 1.7 (1.3 to 2.2) | 0.39 (0.19 to 0.81) |
| CPSS =3 | 30 (19 to 43) | 91 (85 to 96) | 62 (42 to 79) | 73 (65 to 80) | 2.3 (1.6 to 3.4) | 0.52 (0.32 to 0.84) |
| C-STAT ≥2 | 32 (20 to 46) | 91 (85 to 96) | 62 (42 to 79) | 76 (68 to 82) | 2.5 (1.7 to 3.8) | 0.50 (0.31 to 0.81) |
| FAST-ED ≥4 | 42 (29 to 56) | 95 (90 to 98) | 79 (60 to 92) | 79 (72 to 85) | 3.8 (2.7 to 5.5) | 0.26 (0.13 to 0.53) |
| G-FAST ≥3 | 30 (20 to 41) | 94 (88 to 98) | 79 (60 to 92) | 65 (56 to 72) | 2.2 (1.7 to 3.0) | 0.32 (0.16 to 0.66) |
| mNIHSS ≥6 | 25 (17 to 36) | 94 (87 to 98) | 79 (60 to 92) | 56 (48 to 64) | 1.8 (1.4 to 2.3) | 0.37 (0.18 to 0.76) |
| NIHSS ≥6 | 23 (15 to 32) | 95 (87 to 99) | 86 (68 to 96) | 46 (38 to 54) | 1.6 (1.3 to 2.0) | 0.30 (0.12 to 0.76) |
| NIHSS ≥10 | 34 (22 to 48) | 92 (86 to 96) | 66 (46 to 82) | 76 (69 to 83) | 2.7 (1.9 to 4.0) | 0.45 (0.27 to 0.75) |
| PASS ≥2 | 25 (16 to 37) | 91 (84 to 96) | 66 (46 to 82) | 64 (56 to 71) | 1.8 (1.3 to 2.5) | 0.54 (0.32 to 0.90) |
| RACE ≥5 | 36 (23 to 52) | 91 (85 to 95) | 59 (39 to 77) | 81 (74 to 87) | 3.0 (1.9 to 4.7) | 0.51 (0.33 to 0.80) |
| SAVE ≥2 | 27 (18 to 37) | 96 (89 to 99) | 86 (68 to 96) | 57 (49 to 65) | 2.0 (1.6 to 2.5) | 0.24 (0.10 to 0.61) |
| VAN + | 29 (20 to 40) | 95 (89 to 98) | 83 (64 to 94) | 62 (54 to 70) | 2.2 (1.7 to 2.8) | 0.28 (0.12 to 0.62) |
| PPV ≥80% with highest simultaneous NPV | ||||||
| FAST-ED ≥7 | 83 (36 to 100) | 87 (81 to 91) | 17 (6 to 36) | 99 (97 to 100) | 27 (3.2 to 220) | 0.83 (0.71 to 0.98) |
| PPV ≥50% with highest simultaneous NPV | ||||||
| FAST-ED ≥6 | 53 (27 to 79) | 88 (82 to 92) | 28 (13 to 47) | 96 (91 to 98) | 6.1 (2.4 to 15.5) | 0.76 (0.60 to 0.95) |
| PASS =3 | 50 (31 to 69) | 90 (85 to 95) | 48 (29 to 68) | 91 (85 to 95) | 5.3 (2.9 to 9.9) | 0.57 (0.40 to 0.81) |
| RACE ≥7 | 55 (32 to 76) | 90 (84 to 94) | 41 (24 to 61) | 94 (89 to 97) | 6.4 (3.1 to 13.4) | 0.63 (0.46 to 0.85) |
| NPV ≥95% with highest simultaneous PPV | ||||||
| CPSS ≥2 | 23 (15 to 31) | 96 (88 to 99) | 90 (73 to 98) | 43 (35 to 51) | 1.6 (1.3 to 1.9) | 0.24 (0.08 to 0.72) |
| FAST-ED ≥4 | 42 (29 to 56) | 95 (90 to 98) | 79 (60 to 92) | 79 (72 to 85) | 3.8 (2.7 to 5.5) | 0.26 (0.13 to 0.53) |
| G-FAST ≥2 | 22 (15 to 30) | 97 (89 to 100) | 93 (77 to 99) | 38 (30 to 46) | 1.5 (1.3 to 1.8) | 0.18 (0.05 to 0.70) |
| mNIHSS ≥2 | 20 (14 to 27) | 100 (90 to 100) | 100 (88 to 100) | 23 (17 to 31) | 1.3 (1.2 to 1.4) | 0 |
| NIHSS ≥6 | 23 (15 to 32) | 95 (87 to 99) | 86 (68 to 96) | 46 (38 to 54) | 1.6 (1.3 to 2.0) | 0.30 (0.12 to 0.76) |
| PASS ≥1 | 19 (13 to 26) | 95 (84 to 99) | 93 (77 to 99) | 25 (19 to 33) | 1.2 (1.1 to 1.4) | 0.27 (0.07 to 1.1) |
| RACE ≥3 | 30 (20 to 41) | 95 (89 to 98) | 83 (64 to 94) | 64 (56 to 71) | 2.3 (1.8 to 3.0) | 0.27 (0.12 to 0.60) |
| SAVE ≥2 | 27 (18 to 37) | 96 (89 to 99) | 86 (68 to 96) | 57 (49 to 65) | 2.0 (1.6 to 2.5) | 0.24 (0.10 to 0.61) |
| VAN + | 29 (20 to 40) | 95 (89 to 98) | 83 (64 to 94) | 62 (54 to 70) | 2.2 (1.7 to 2.8) | 0.28 (0.12 to 0.62) |
The prevalence of LVO stroke using the ICA, M1, M2 or basilar occlusion definition of LVO stroke was 15.8% in this subset of patients with NIHSS subitems documented.
AAW +, asymmetric arm weakness positive; CPSS, Cincinnati Prehospital Stroke Scale; C-STAT, Cincinnati Stroke Triage Assessment Tool; FAST-ED, Field Assessment Stroke Triage for Emergency Destination; G-FAST, Gaze-Face-Arm-Speech-Time; ICA, internal carotid artery; LVO, large vessel occlusion; M1, first division of the middle cerebral artery; M2, second division of the middle cerebral artery; mNIHSS, modified National Institutes of Health Stroke Scale; NIHSS, National Institutes of Stroke Scale; NLR, negative likelihood ratio; NPV, negative predictive value; PLR, positive likelihood ratio; PPV, positive predictive value; RACE, Rapid Arterial oCclusion Evaluation; SAVE, Speech Arm Vision Eyes; VAN +, Vision Aphasia Neglect positive.