Characteristics of the study participants and sites evaluated
| Characteristics | Site 1 | Site 2 | Site 3 |
| Yearly visits | 46 000 | 32 000 | 28 000 |
| Shifts per day | 6–7 | 4 | 3–4 |
| Shifts evaluated | 4444 | 2920 | 2458 |
| Physicians working during the study period | 22 | 17 | 25 |
| Maximum number of concurrent physicians | 3 | 2 | 2 |
| Hours of single provider coverage | 6 | 12 | 12 |
| Hours of mid-level provider coverage | 16 | 18 | 14 |
| Mean patients per shift | 15.0 (SD 4.7) | 20.9 (SD 6.4) | 13.2 (SD 3.8) |
| Percentage Emergency Severity Index 3 or more acute | 73.1 | 76.2 | 76.9 |