Table 1

Baseline characteristics

Characteristics*Repeated imaging (n=165)No repeated imaging (n=386) p value
Age, years – mean±SD71±15.370±13.30.40
Male sex – no./total (%)79/165 (48%)200/386 (52%)0.40
Hypertension – no./total (%)68/164 (41%)150/382 (39%)0.63
Diabetes mellitus – no./total (%)21/164 (13%)56/382 (15%)0.57
Atrial fibrillation – no./total (%)34/164 (21%)95/382 (25%)0.30
Coronary artery disease – no./total (%)14/164 (9%)80/382 (21%)<0.01
Previous stroke – no./total (%)30/164 (18%)66/382 (17%)0.78
Pre-stroke mRS score† – median (IQR)1 (0–1)1 (0–1)0.72
Systolic blood pressure (mm Hg) – mean±SD150±28.1148±23.90.37
Diastolic blood pressure (mm Hg) – mean±SD83±17.082±16.50.65
NIHSS score at PSC arrival‡ – median (IQR)11 (7–15)13 (9–17)<0.01
NIHSS score at CSC arrival§ – median (IQR)9 (4–17)16 (10–20)<0.01
Intracranial occlusion site (on PSC imaging) – no./total (%)0.07
 ICA26/164 (16%)76/386 (20%)
 M190/164 (55%)228/386 (59%)
 Proximal M231/164 (19%)38/386 (10%)
 Anterior cerebral artery0/164 (0%)1/386 (0%)
 Basilar artery13/164 (8%)31/386 (8%)
 No LVO (misread by radiologist at PSC)4/164 (2%)12/386 (3%)
Reason for repeating imaging – no./total (%)
 Clinical improvement86/165 (52%)NA
 Clinical deterioration40/165 (24%)NA
 Additional imaging characteristics for assessing indication for EVT**11/165 (7%)NA
 Other6/165 (4%)NA
 Reason not recorded22/165 (13%)NA
Presentation outside office hours – no./total (%)74/150 (49%)233/365 (64%)<0.01
Time from stroke onset to arrival at PSC (min)¶ – median (IQR)50 (30–81)58 (32–95)0.14
Treatment with IVT – no./total (%)135/165 (82%)276/386 (72%)0.01
  • *All baseline characteristics were measured on arrival at the CSC, unless reported otherwise.

  • †Number of missing values: 350.

  • ‡28.

  • §4.

  • ¶178.

  • **For example, ASPECTS, collaterals, core/penumbra ratio <6 hours.

  • ASPECTS, Alberta Stroke Program Early CT Score; CSC, comprehensive stroke center; EVT, endovascular treatment; ICA, intracranial part of internal carotid artery; IVT, intravenous thrombolysis; LVO, large vessel occlusion; M1, first segment of the middle cerebral artery; M2, proximal part of the second segment (after first bifurcation) of the middle cerebral artery; mRS, modified Rankin Scale; NA, not applicable; NIHSS, National Institutes of Health Stroke Scale; no., number; PSC, primary stroke center.