Group 1: No CPR prior to call (CPRduring) | Copenhagen (N = 200) | Stockholm (N = 200) | Oslo (N = 200) | p-value |
 Consciousness addressed | 168/200 (84) | 189 /200 (95) | 199/200 (100) | p = 0.001 |
 Unknown | 17/200 (9) | – | – | |
 Breathing addressed | 169/200 (85) | 196 /200 (98) | 199/200 (100) | p < 0.001 |
 Unknown | 19/200 (10) | – | – | |
 Abnormal breathing addressed | 68/200 (34) | 13/200 (7) | 195/200 (98) | p < 0.001 |
 Unknown | 15/200 (8) | 1/200 (1) | – | |
 OHCA recognition | 142/200 (71) | 165/200 (83) | 192/200 (96) | p < 0.001 |
 Unknown | 13/200 (7) | – | 1/200 (1) | |
 CPR instructions started | 99/200 (50) | 120/200 (60) | 160/200 (80) | p < 0.001 |
 Unknown | 24/200 (12) | – | – | |
  Dispatcher is assertive when providing CPR instructions | 84/99 (85) | 101/120 (84) | 145/160 (91) | p = 0.2 |
  Unknown | – | 3/120 (3) | – | |
  Quality assessment | 79/99 (80) | 89/120 (74) | 119/160 (74) | p = 0.2 |
  Unknown | – | 7/120 (6) | – | |
  Encouraging/motivating techniques in use | 69/99 (70) | 99/120 (83) | 132/160 (83) | p < 0.001 |
 Chest compressions performed | 109/200 (55) | 119/200 (60) | 157/200 (79) | p < 0.001 |
 Unknown | – | 5/200 (3) | 4/200 (2) | |
 Type of CPR |  |  |  | p = 0.3 |
  30:2 | 24/109 (22) | 30/119 (25) | 46/157 (29) |  |
  Compressions only | 85/109 (78) | 77/119 (65) | 102/157 (65) |  |
  Unknown | – | 20/119 (17) | 9/157 (6) |  |
 BLS competence addressed | 88/200 (44) | 101/200 (51) | 63/200 (32) | p < 0.001 |
 Unknown | 30/200 (15) | 1/200 (1) | – | |
 AED addressed | 22/200 (11) | 8/200 (4) | 6/200 (3) | p < 0.001 |
 Unknown | 51/200 (26) | – | – | |
 Call continued until EMS arrival | 85/200 (43) | 128/200 (64) | 163/200 (82) | p < 0.001 |
 Unknown | 14/200 (7) | – | 3/200 (2) | |
 Time intervals for recognition and CPR instructions | ||||
  Time to OHCA recognition (min:sec) | 01:16 [IQR 00:50–02:11] | 01:53 [IQR 1:01–3:13] | 01:19 [IQR 0:50–2:09] | p < 0.001 |
  Time to chest compression instructions (min) | 02:10 [IQR 01:27–03:25] | 03:20 [IQR 02:03–04:56] | 02:24 [IQR 01:37–04:00] | p < 0.001 |
  Time to chest compressions performed (min) | 02:35 [IQR 01:45–03:05] | 03:50 [IQR 02:30–05:27] | 02:58 [IQR 02:09–04:36] | p < 0.001 |
Group 2: CPR initiated prior to call (CPRprior) | Copenhagen (N = 69) | Stockholm (N = 9) | Oslo (N = 38) |  |
 CPR instructions started | 28/69 (41) | 2/9 (22) | 15/38 (40) |  |
 Unknown | 8/69 (12) | – | – |  |
  Dispatcher is assertive when providing CPR instructions | 24/28 (86) | 2/2 (100) | 15/15 (100) |  |
  Quality assessment | 20/28 (71) | 2/2 (100) | 12/15 (80) |  |
  Encouraging/motivating techniques in use | 20/28 (71) | 2/2 (100) | 14/15 (93) |  |
 Type of CPR | ||||
  30:2 | 17/69 (25) | 1/9 (11) | 7/38 (18) |  |
  Compressions only | 30/69 (43) | 1/9 (11) | 12/38 (32) |  |
  Unknown | 22/69 (32) | 7/9 (78) | 19/38 (50) |  |
 AED addressed | 27/69 (39) | 3/9 (33) | 4/38 (11) |  |
 Call continued until EMS arrival | 25/69 (36) | 4/9 (44) | 19/38 (50) |  |