Table 1

Final diagnoses and participant characteristics in the prevalence and diagnostic performance studies

CharacteristicsPrevalence study
(n=220)
Diagnostic performance study subset of patients
(n=184)
Final diagnosis
 LVO stroke, n (%)30 (13.6)29 (15.8)
 M1 occlusions77
 Tandem extracranial ICA and M144
 Tandem intracranial ICA and M133
 ICA terminus, M1, and A111
 Extra and intracranial ICA11
 Isolated M2 occlusions1010
 Tandem extracranial ICA and M211
 Tandem extracranial ICA and P210
 Basilar occlusions22
 Intracranial haemorrhage, n (%)35 (15.9)19 (10.3)
 ICH ≥30 mL, n84
 Non-LVO ischaemic stroke, n (%)45 (20.5)43 (23.4)
 Mimics, n (%)110 (50)93 (50.5)
Age in years, median (IQR)70 (61–81)70 (61–80)
Sex (male), n (%)118 (54)94 (51)
Hypertension, n (%)138 (63)116 (63)
Hyperlipidaemia, n (%)74 (37)63 (34)
Diabetes, n (%)76 (35)65 (35)
Atrial fibrillation by history or at presentation, n (%)33 (15)28 (15)
Seizure or seizure history, n (%)25 (11)19 (10)
Prior ischaemic stroke, n (%)41 (19)36 (20)
Prior haemorrhagic stroke, n (%)12 (5)10 (5)
Known anticoagulation use, n (%)17 (8)13 (7)
Baseline NIHSS, median (IQR)*8 (4–14)7 (3–14)
Baseline NIHSS <6, n (%)91 (46)75 (41)
Received intravenous alteplase, n (%)50 (23)46 (25)
Alteplase given prior to CTA, n (%)23 (10)21 (11)
Time between arrival and NCHCT, min, median (IQR)†11 (9–16)11 (9–16)
CTA done on arrival, n (%)166 (75)145 (79)
Time between arrival and CTA, min, median (IQR)‡25 (20–32)25.5 (19–32)
Intubated on arrival imaging, n (%)10 (5)4 (2)
  • Documentation of arrival NIHSS subitem scores was required for inclusion in the diagnostic performance study.

  • *Total NIHSS scores were known for only 197 of the 220 participants in the prevalence study.

  • †One patient in the prevalence study did not have an NCHCT, thus time between arrival and NCHCT is based on 219 patients rather than 220.

  • ‡One patient had missing arrival CTA time data, thus time between arrival and CTA is based on 165 rather than 166 patients in the prevalence study and 144 patients rather than 145 in the diagnostic performance study.

  • A1, first division of the anterior cerebral artery; CTA, CT angiography; ICA, internal carotid artery; ICH, intracerebral haemorrhage; LVO, large vessel occlusion; M1, first division of the middle cerebral artery; M2, second division of the middle cerebral artery; NCHCT, non-contrast head CT; NIHSS, National Institutes of Health Stroke Scale; P2, second division of the posterior cerebral artery.