Table 2.
Summary statistics of subject and episode characteristics*.
| Overall | Before | After | p-value | |
|---|---|---|---|---|
| Number of events | 7403 | 4897 | 2506 | NA |
| Age – mean (sd) | 65.3 (16.9) | 65.0 (16.8) | 65.8 (16.9) | 0.038 |
| Male – N (%) | 4873 (62.7) | 3179 (63.0) | 1694 (62.3) | 0.54 |
| Public Location – N (%) | 1196 (15.4) | 759 (15.0) | 437 (16.1) | 0.23 |
| Home – N (%) | 5582 (71.8) | 3658 (72.4) | 1924 (70.7) | 0.10 |
| Response time – mean (sd) | 5.8 (8.9) | 5.8 (10.7) | 5.7 (3.7) | 0.54 |
| ALS among responders – N (%) | 7270 (93.5) | 4622 (91.5) | 2648 (97.2) | <0.0001 |
| Bystander witnessed – N (%) | 3117 (46.5) | 1999 (45.4) | 1118 (48.6) | 0.012 |
| Bystander CPR – N (%) | 2395 (30.8) | 1449 (28.7) | 946 (34.7) | <0.0001 |
| Initial EMS rhythm VT/VF – N (%) | 1774 (23.5) | 1129(23.1) | 645 (24.2) | 0.28 |
| EMS schocked – N (%) | 2637 (33.9) | 1669 (33.1) | 968 (35.5) | 0.03 |
*
For continuous variables mean and standard deviation are of those with non-missing values. For discrete variables the number and percent are of subjects with non-missing values.