Scenario analysis for early presenters based on travel time difference
| HEMS vs GEMS | HEMS (pInd; pDep; pDead) | GEMS (pInd; pDep; pDead) | ICER | % CE at £20k/QALY | % CE at £30k/QALY |
| Travel time (mins) | 60 min difference | ||||
| 300 vs 360 | 0.57; 0.36; 0.07 | 0.53; 0.39; 0.08 | £28 027 | 14.8 | 62.9 |
| 270 vs 330 | 0.59; 0.35; 0.06 | 0.53; 0.39; 0.08 | £26 318 | 17.4 | 70.6 |
| 240 vs 300 | 0.61; 0.33; 0.06 | 0.57; 0.36; 0.07 | £27 415 | 18.7 | 64.7 |
| 180 vs 240 | 0.64; 0.30; 0.06 | 0.61; 0.33; 0.06 | £41 370 | 14.1 | 26.2 |
| Travel time (min) | 45 min difference | ||||
| 315 vs 360 | 0.56; 0.37; 0.07 | 0.53; 0.39; 0.08 | £37 545 | 8.3 | 25.4 |
| 285 vs 330 | 0.58; 0.35; 0.07 | 0.55; 0.37; 0.08 | £35 266 | 9.4 | 27.7 |
| 255 vs 300 | 0.60; 0.34; 0.06 | 0.57; 0.36; 0.07 | £34 864 | 10.8 | 29.1 |
| 195 vs 240 | 0.63; 0.31; 0.06 | 0.61; 0.33; 0.06 | £58 414 | 8.8 | 16.6 |
CE, cost-effective; GBA, ground-based ambulance; GEMS, ground emergency medical services; HEMS, helicopter emergency medical services; ICER, incremental cost-effectiveness ratio; QALY, quality-adjusted life year.