Table 2

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 strokePPV %
(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 =330 (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 ≥232 (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 ≥442 (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 ≥330 (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 ≥625 (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 ≥623 (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 ≥1034 (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 ≥225 (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 ≥536 (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 ≥227 (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 ≥783 (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 ≥653 (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 =350 (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 ≥755 (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 ≥223 (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 ≥442 (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 ≥222 (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 ≥220 (14 to 27)100 (90 to 100)100 (88 to 100)23 (17 to 31)1.3 (1.2 to 1.4)0
 NIHSS ≥623 (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 ≥119 (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 ≥330 (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 ≥227 (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.