Multivariable Poisson regression evaluating predictors of lag time
| Predictor | Category | IRR | 95% CI | p Value |
| Profession | Non-physician | Reference | ||
| Physician | 1.75 | 1.65 to 1.87 | <0.0001 | |
| Severity of injury | Minor | Reference | ||
| Major | 1.34 | 1.15 to 1.56 | 0.0002 | |
| Hospital | BWH | Reference | ||
| KUH | 2.95 | 2.84 to 3.06 | <0.0001 | |
BWH, Brigham and Women's Hospital; IRR, incidence–rate ratio; KUH, Kyoto University Hospital.