Table 2. Summary table of categorical variables relating to ambulance transports to hospital stratified by prealert (% prealerted for each category).
| Characteristic | Site 1 prealert/total (%) | Site 2 prealert/total (%) | Site 3 prealert/total (%) | Total prealert/ total (%) |
| Overall | 60 549/413 140 (14.7) | 51 142//623 325 (8.2) | 31 104/326 809 (9.5) | 142 795/1 363 274 (10.5) |
| Simplified clinician role | ||||
| Paramedic | 46 665/305 549 (15) | 39 342/485 978 (8.1) | 21 302/211 206 (10) | 107 309/1 002 733 (11) |
| Non-paramedic | 13 884/107 591 (13) | 11 800/137 347 (8.6) | 9802/115 603 (8.5) | 35 486/360 541 (9.8) |
| Patient sex | ||||
| Male | 31 550/196 484 (16) | 26 922/298 979 (9.0) | 16 263/157 058 (10) | 74 735/652 521 (11) |
| Female | 27 871/210 636 (13) | 23 835/319 200 (7.5) | 14 764/168 699 (8.8) | 66 470/698 535 (9.5) |
| Not specified | 0/0 | 385/5146(7.5) | 53/691(7.7) | 438/5837(7.5) |
| Transgender | 15/163(9.2) | 0/0 | 22/355(6.2) | 37/518(7.1) |
| Working Impression (conditions with >5 k prealerts only) | ||||
| Sepsis | 6705/10 138(66) | 11 402/20 679 (55) | 3372/4004(84) | 21 479/34 821 (62) |
| Unspecified medical condition | 5668/62 620(9.1) | 8673/165 959 (5.2) | 2470/48 208(5.1) | 16 811/276 787 (6.1) |
| Acute stroke | 5881/8308(71) | 6417/13 812(46) | 2571/5663(45) | 14 869/27 783 (54) |
| Other working impression | 5791/71 923(8.1) | 3848/90 264(4.3) | 2134/54 066(3.9) | 11 773/216 253 (5.4) |
| COVID-19 | 3525/13 942(25) | 4481/25 550(18) | 928/4285(22) | 8934/43 777 (20) |
| Respiratory problem | 5839/26 628(22) | 676/6479(10) | 2070/15 144(14) | 8585/48 251 (18) |
| Arrhythmia | 2504/6740(37) | 1530/10 335(15) | 1970/8069(24) | 6004/25 144 (24) |
| Lower respiratory tract infection | 926/5059(18) | 2321/19 489(12) | 2532/13 287(19) | 5779/37 835 (15) |
| Cardiac problem | 1919/21 419(9.0) | 701/22 097(3.2) | 2687/34 571(7.8) | 5307/78 087 (6.8) |
| Any RCEM prealert criteria triggered | 40 437/98 149 (41) | 40 250/145 989 (28) | 22 536/80 461 (28) | 103 223/324 599 (32) |
| Any RCEM physiological criteria triggered | 28 990/79 956 (36) | 29 027/117 873 (25) | 18 911/71 907 (26) | 76 928/269 736 (29) |
| Any RCEM non-physiological criteria triggered | 22 566/34 267 (66) | 24 722/57 871 (43) | 8658/17 209 (50) | 55 946/109 347 (51) |
Further details are provided in online supplemental additional file 4.
RCEMRoyal College of Emergency Medicine