Baseline characteristics of the study groups
| Total | Breathing information available | Breathing information not available | ||||
|---|---|---|---|---|---|---|
| Characteristics | (N=659) | (N=283) | (N=376) | |||
| Men, n (%) | 408 | (61.9) | 174 | (61.5) | 234 | (62.2) |
| Age, years, median (IQR) | 76 | (66–84) | 76 | (68–84) | 76 | (65–83) |
| Victims with disabilities in daily life, n (%) | 76 | (20.2) | 36 | (12.7) | 40 | (10.6) |
| Cardiac arrest at home, n (%) | 551 | (83.6) | 254* | (89.8) | 297 | (79.0) |
| Victims described as breathing in various ways, n (%) | – | – | 169 | (59.7) | – | – |
| Initial rhythm of VF/VT, n (%) | 113 | (17.1) | 43 | (15.2) | 70 | (18.6) |
| Call–arrival time, min, median (IQR) | 7 | (5–10) | 7 | (6–9) | 7 | (5–10) |
| Advanced airway management by EMS, n (%) | 449 | (68.1) | 204 | (72.1) | 245 | (65.2) |
| Epinephrine administration by EMS, n (%) | 83 | (12.6) | 42 | (14.8) | 41 | (10.9) |
| Time from call to hospital arrival, min, median (IQR) | 35 | (28–44) | 35 | (29–44) | 35 | (27–44) |
All the continuous variables were presented as medians and IQRs, and the categorical variables were expressed as numbers and percentages.
*p<0.05 by χ2 test.
EMS, emergency medical service; VF/VT, ventricular fibrillation and pulseless ventricular tachycardia.