A Propensity Score-Matched Comparison of In-Hospital Mortality between Dedicated Regional Trauma Centers and Emergency Medical Centers in the Republic of Korea
Table 1
General characteristics of the study population and the propensity score-matched samples. Continuous variables were compared using the independent t-test, and categorical variables were compared using the chi-square test.
Original study population
value
Matched samples
value
RTC (N = 27108)
EMC (N = 1000026)
RTC (N = 26694)
EMC (N = 26694)
Male sex
17382 (64.1)
566882 (56.7)
<0.001
17060 (63.9)
15838 (59.3)
<0.001
Age
46.7 ± 19.1
46.3 ± 18.8
0.001
46.6 ± 19.1
46.8 ± 19.5
0.280
Insurance type
<0.001
0.001
National health
16520 (60.9)
738396 (73.8)
16468 (61.7)
16789 (62.9)
Automobile
6917 (25.5)
168181 (16.8)
6728 (25.2)
6487 (24.3)
Occupational hazard
548 (2.0)
5960 (0.6)
492 (1.8)
521 (2.0)
Health aid type 1
821 (3.0)
32408 (3.2)
817 (3.1)
860 (3.2)
Health aid type 2
248 (0.9)
8922 (0.9)
246 (0.9)
275 (1.0)
Others
46159 (4.6)
2054 (7.6)
1943 (7.3)
1762 (6.6)
Mechanism
<0.001
<0.001
Traffic car
4487 (16.6)
127319 (12.7)
4424 (16.6)
4071 (15.3)
Traffic bicycle
864 (3.2)
19894 (2.0)
846 (3.2)
909 (3.4)
Traffic motorcycle
1626 (6.0)
28134 (2.8)
1555 (5.8)
1543 (5.8)
Traffic others
1845 (6.8)
33091 (3.3)
1745 (6.5)
1683 (6.3)
Fall from heights
2526 (9.3)
51973 (5.2)
2401 (9.0)
2400 (9.0)
Fall from level
5062 (18.7)
201653 (20.2)
5059 (19.0)
5324 (19.9)
Struck by person or object
5177 (19.1)
179780 (18.0)
5159 (19.3)
5297 (19.8)
Firearm, cut, or pierce
3776 (13.9)
176449 (17.6)
3766 (14.1)
3693 (13.8)
Machine
392 (1.4)
14974 (1.5)
386 (1.4)
359 (1.3)
Others
1353 (5.0)
166759 (16.7)
1353 (5.1)
1415 (5.3)
Intent
<0.001
<0.001
Accidental-unintentional
25108 (92.6)
926081 (92.6)
24728 (92.6)
24794 (92.9)
Intentional or self-harm
511 (1.9)
9032 (0.9)
495 (1.9)
557 (2.1)
Violence or assault
1186 (4.4)
46437 (4.6)
287 (1.1)
160 (0.6)
Others
303 (1.1)
18476 (1.8)
1184 (4.4)
1183 (4.4)
Mode of transport
<0.001
0.044
Ambulance
13394 (49.4)
289841 (29.0)
12988 (48.7)
12754 (47.8)
Others
13714 (50.6)
710185 (71.0)
13706 (51.3)
13940 (52.2)
Respiratory rate (min−1)
19.2 ± 2.6
19.2 ± 2.2
0.268
19.1 ± 2.5
19.4 ± 3.2
<0.000
Pulse oxygen saturation (%)
97.3 ± 4.0
97.9 ± 3.9
<0.001
97.4 ± 3.7
97.6 ± 4.2
0.001
Body temperature (°C)
36.6 ± 0.5
36.5 ± 0.6
<0.001
36.6 ± 0.6
36.6 ± 0.5
0.000
Systolic blood pressure (mmHg)
135.0 ± 24.0
134.8 ± 21.6
0.085
135.2 ± 23.7
135.5 ± 24.7
0.134
Heart rate (min−1)
85.3 ± 15.5
82.8 ± 13.6
<0.001
85.0 ± 15.2
84.9 ± 15.6
0.395
Responsiveness
<0.001
0.173
Alert
24940 (92.0%)
988403 (98.8%)
24835 (93.0)
24716 (92.6)
Response to voice
1176 (4.3%)
7826 (0.8%)
1021 (3.8)
1059 (4.0)
Response to pain
789 (2.9%)
3261 (0.3%)
660 (2.5)
733 (2.7)
Unresponsive
203 (0.7%)
536 (0.1%)
178 (0.7)
186 (0.7)
SRR of primary diagnosis
0.99 ± 0.02
1.00 ± 0.01
<0.001
0.99 ± 0.02
0.99 ± 0.02
0.041
KTAS
<0.001
<0.001
1
517 (1.9)
1064 (0.1)
416 (1.0)
430 (1.6)
2
3684 (13.6)
15387 (1.5)
3372 (12.6)
3527 (13.2)
3
5160 (19.0)
154128 (15.4)
5159 (19.3)
4622 (17.3)
4
14459 (53.3)
669423 (66.9)
14459 (54.2)
14830 (55.6)
5
3288 (12.1)
160024 (16.0)
3288 (12.3)
3285 (12.3)
Anatomic locations of injury
Head injury
12874 (47.5)
311749 (31.2)
<0.001
12528 (46.9)
12707 (47.6)
0.123
Neck injury
2532 (9.3)
80550 (8.1)
<0.001
2478 (9.3)
2043 (7.7)
<0.001
Chest
4341 (16.0)
68075 (6.8)
<0.001
4030 (15.1)
3614 (13.5)
<0.001
Abdomen or pelvis
3834 (14.1)
100413 (10.0)
<0.001
3630 (13.6)
3122 (11.7)
<0.001
Upper limb
6548 (24.2)
273027 (27.3)
<0.001
6426 (24.1)
6171 (23.1)
0.010
Lower limb
5311 (19.6)
213899 (21.4)
<0.001
5213 (19.5)
4870 (18.2)
<0.001
Unspecified
3108 (11.5)
174816 (17.5)
<0.001
3105 (11.6)
3283 (12.3)
0.018
Number of involved anatomic locations of injury
1.3 ± 1.0
1.0 ± 0.8
<0.001
1.3 ± 1.0
1.2 ± 0.9
<0.001
Disposition from the ED
<0.001
<0.001
Admission to ICU
3830 (14.1)
10462 (1.0)
3471 (13.0)
1819 (6.8)
Admission to ward
4304 (15.9)
4304 (15.9)
4268 (16.0)
3561 (13.3)
Admission to other units
0 (0.0)
22 (0.0)
0 (0.0)
1 (0.0)
Discharge
18864 (69.6)
872682 (87.3)
18859 (70.7)
21107 (79.1)
Hopeless discharge
1 (0.0)
24 (0.0)
1 (0.0)
3 (0.0)
Death
31 (0.1)
253 (0.0)
17 (0.1)
100 (0.4)
Others
70 (0.3)
3536 (0.4)
70 (0.3)
102 (0.4)
RTC: regional trauma center; EMC: emergency medical center; SRR: survival risk ratio; KTAS: Korean Triage and Acuity Scale.
