Factors associated with EMS use for patients arrived within 24 hours and patients arrived within 3.5 hours
| Variables | Arrival by 24 hours (n=3555), OR (95% CI) | P value | Arrival by 3.5 hours (n=2123), OR (95% CI) | P value |
| Age (per 5 year increase) | 1.06 (1.04–1.09) | <0.001 | 1.05 (1.02–1.08) | <0.001 |
| Female | 0.87 (0.79–0.97) | 0.01 | – | – |
| Atrial fibrillation | 1.71 (1.37–2.14) | <0.001 | 1.56 (1.33–1.82) | <0.001 |
| Peripheral arterial disease | 1.29 (1.02–1.64) | 0.03 | 1.58 (1.16–2.16) | 0.004 |
| Baseline NIHSS (ref: 0–4) | ||||
| 5–15 | 2.39 (1.89–3.02) | <0.001 | 3.09 (2.86–3.34) | <0.001 |
| 16+ | 9.53 (3.35–27.13) | <0.001 | 7.53 (4.64–12.19) | <0.001 |
| Unknown | 1.69 (1.23–2.33) | 0.001 | 1.85 (1.45–2.27) | <0.001 |
P values are based on logistic regressions with the generalised estimating equations, and logistic regressions with the generalised estimating equations after stepwise selection for adjusted OR.
EMS, emergency medical services; NIHSS, National Institutes of Health Stroke Scale.