Table 2

Cox Regression analysis estimating association of prehospital care on times to CT request and scan

PredictorUnadjustedAdjusted*
HR95% CIp ValueHR95% CIp Value
Onset time recorded vs not recorded by EMS
 Time to scan request0.670.480.940.0200.730.521.030.070
 Time to scan0.600.420.840.0030.610.420.880.008
FAST+ vs FAST−/Not done
 Time to scan request0.540.370.800.002 0.540.370.800.002
 Time to scan0.740.501.090.123 0.720.481.080.108
Hospital prealerted vs not prealerted by EMS
 Time to scan request0.230.160.34<0.001 0.260.180.38<0.001
 Time to scan0.460.320.65<0.001 0.630.430.940.022
  • HR represents the likelihood of the CT request/scan being delayed in those who have a known onset time, are FAST+ or where a hospital prealert message was sent.

  • *HRs were adjusted for EMS recording of onset time, FAST status, patient age, route to hospital, arrival in hospital within 4 h of symptom onset, Glasgow Coma Score, and whether the hospital was prealerted by EMS staff prior to arrival in the ED provided they were independent of the explanatory and outcome variables. Full details of each proportional hazards model can be found in online supplementary table S2.

  • EMS, emergency medical service; FAST, Face Arm Speech Test.