Table 1 Descriptive data of the development and the validation dataset

Year of accident

2010 - 2011

2012

Number of cases

30,866

21,918

Age

47.3/47 (21.7)

48.4/48 (21.9)

Male sex

21,899 (71.6%)

15,430 (70.4%)

Blunt mechanism

27,701 (95.5%)

19,720 (94.9%)

Head injury (AIS ≥3)

10,498 (34.0%)

6,791 (31.0%)

Chest injury (AIS ≥3)

12,126 (39.3%)

8,022 (36.6%)

Abdominal injury (AIS ≥3)

3,375 (10.9%)

2,136 (9.7)

Injury of extremities and pelvic ring (AIS ≥3)

8,252 (26.7%)

5,390 (24.6%)

Injury Severity Score (ISS)

19.3/17 (13.1)

18.0/16 (12.6)

New ISS

24.1/22 (15.8)

22.6/17 (15.4)

ISS ≥16

17,045 (55.2%)

10,995 (50.2%)

Type of injury

- traffic: car

7,183 (23.3%)

4.999 (22.8%)

- traffic: motorbike

4,129 (13.4%)

2,859 (13.0%)

- traffic: bicycle

2,492 (8.1%)

1,907 (8.7%)

- traffic: pedestrian

2,066 (6.7%)

1,476 (6.7%)

- high fall (>3 m)

5,086 (16.5%)

3,389 (15.5%)

- low fall (<3 m)

5,339 (17.3%)

4,171 (19.0%)

Length of stay in hospital (days)

17.9/13 (18.8)

16.7/12 (17.5)

Hospital mortality

3,557 (11.5%)

2,378 (10.8%)

RISC score available

26,041 (84.4%)

19,501 (89.0%)

TRISS score available

17,411 (56.4%)

12,450 (56.8%)

Transportation to hospital by helicopter

7,297 (24.3%)

4,528 (21.2%)

Hospital level of care

- supra-regional trauma centre (level 1)

18,119 (58.7%)

12,556 (57.3%)

- regional trauma centre (level 2)

10,439 (33.8%)

7,427 (33.9%)

- local trauma centre (level 3)

2,309 (7.5%)

1,935 (8.8%)