Table 2. Population Characteristics by Trauma Level in Full Population and After Propensity Score Matching.
| Characteristic | No. (%) | Level III (n = 62 830) | Non-trauma center (n = 206 275) | ||||
|---|---|---|---|---|---|---|---|
| Level I (n = 67 485) | Level II (n = 94 007) | SMDa | No. (%) | SMDa | No. (%) | SMDa | |
| Full population | |||||||
| Age group, y | |||||||
| 65-74 | 15 804 (23.4) | 18 865 (20.1) | −0.12 | 12 144 (19.3) | −0.13 | 35 198 (17.0) | −0.06 |
| 75-84 | 23 218 (34.4) | 32 638 (34.7) | 22 228 (35.4) | 70 002 (33.9) | |||
| ≥85 | 28 463 (42.2) | 42 574 (45.3) | 28 458 (45.3) | 101 475 (49.1) | |||
| CCI score | |||||||
| 0 | 21 320 (31.6) | 30 066 (31.9) | 0.04 | 19 525 (31.1) | 0.03 | 66 675 (32.3) | 0.02 |
| 1 | 16 072 (23.8) | 22 749 (24.2) | 15 282 (24.3) | 50 377 (24.4) | |||
| 2 | 11 130 (16.5) | 15 463 (16.4) | 10 466 (16.7) | 34 183 (16.5) | |||
| ≥3 | 18 963 (28.1) | 25 799 (27.4) | 17 557 (27.9) | 55 440 (26.8) | |||
| Frail | 33 847 (50.2) | 48 800 (51.9) | 0.05 | 32 748 (52.1) | −0.06 | 110 001 (53.2) | −0.02 |
| Sex | |||||||
| Female | 42 694 (63.3) | 63 330 (67.3) | −0.12 | 44 207 (70.4) | −0.21 | 148 754 (71.9) | −0.07 |
| Male | 24 694 (36.7) | 30 677 (32.7) | 18 623 (29.6) | 57 521 (28.1) | |||
| Race | |||||||
| Asian | 1265 (1.9) | 1082 (1.2) | 0.08 | 404 (0.6) | 0.16 | 3109 (1.5) | 0.01 |
| Black | 4345 (6.4) | 3142 (3.3) | 0.20 | 1875 (2.9) | 0.23 | 7894 (3.8) | 0.04 |
| Hispanic | 766 (1.1) | 952 (1.0) | 0.02 | 758 (1.2) | −0.01 | 2757 (1.3) | −0.01 |
| White | 59 781 (88.6) | 87 567 (93.1) | −0.22 | 58 894 (93.7) | −0.26 | 190 078 (91.9) | −0.04 |
| Otherb | 1083 (1.6) | 1104 (1.2) | 0.05 | 761 (1.2) | 0.05 | 2361 (1.1) | 0.01 |
| Unknown | 245 (0.4) | 230 (0.2) | 0.03 | 138 (0.2) | 0.04 | 476 (0.2) | 0.01 |
| Trauma center proximity | |||||||
| In county | 53 621 (79.5) | 70 214 (74.6) | −0.17 | 46 424 (73.9) | −0.19 | 118 550 (57.4) | −0.17 |
| Adjacent county | 11 297 (16.7) | 1872 (20.1) | 12 870 (20.5) | 67 008 (32.4) | |||
| No trauma center | 2567 (3.8) | 4991 (21.8) | 3536 (14.6) | 21 117 (10.2) | |||
| AIS score ≥3 | |||||||
| Head and neck | 14 677 (21.8) | 14 649 (15.6) | 0.22 | 5118 (8.2) | 0.59 | 14 218 (6.9) | 0.17 |
| Face | 59 (0.1) | 38 (0.1) | 0.12 | <10c | 0.27 | 21 (0.1) | 0.07 |
| Chest | 5926 (8.8) | 5104 (5.4) | 0.20 | 2566 (4.1) | 0.34 | 5322 (2.6) | 0.11 |
| Abdomen and pelvis | 1069 (1.6) | 782 (0.8) | 0.10 | 303 (0.5) | 0.19 | 562 (0.3) | 0.05 |
| Extremity | 25 614 (37.9) | 41 384 (43.9) | −0.20 | 34 562 (55.0) | −0.55 | 112 604 (54.5) | −0.14 |
| External | 245 (0.4) | 114 (0.1) | 0.13 | 89 (0.1) | 0.27 | 216 (0.1) | 0.08 |
| Injury subtype | |||||||
| Cervical spine fracture | 1664 (2.5) | 2097 (2.2) | NA | 733 (1.2) | NA | 1991 (1.0) | NA |
| Hip fracture and TBI | 830 (1.2) | 1359 (1.4) | NA | 754 (1.2) | NA | 2122 (1.0) | NA |
| Isolated fracture | |||||||
| Hip | 23 827 (35.3) | 40 363 (42.9) | NA | 34 244 (54.5) | NA | 115 471 (55.9) | NA |
| Rib | 3058 (4.5) | 3838 (4.1) | NA | 2327 (3.7) | NA | 6621 (3.2) | NA |
| Isolated TBI | 10 581 (15.7) | 11 978 (12.7) | NA | 4575 (7.3) | NA | 13 680 (6.6) | NA |
| Other extremity fractured | 8725 (12.9) | 13 235 (14.1) | NA | 9500 (15.1) | NA | 32 455 (15.7) | NA |
| Other injurye | 7970 (11.8) | 10 825 (11.5) | NA | 6575 (10.5) | NA | 24 106 (11.7) | NA |
| Multiple traumas | 10 830 (16.1) | 10 382 (11.0) | NA | 4122 (6.6) | NA | 10 229 (5.0) | NA |
| After propensity score matching | |||||||
| Total No. | 51 638 | 51 638 | 51 638 | 51 638 | |||
| Age group, y | |||||||
| 65-74 | 10 561 (20.5) | 10 562 (20.5) | 0 | 10 532 (20.5) | 0 | 10 565 (20.5) | 0 |
| 75-84 | 17 561 (34.0) | 17 569 (34.0) | 17 608 (34.0) | 17 546 (34.0) | |||
| ≥85 | 23 516 (45.5) | 23 507 (45.5) | 23 498 (45.5) | 23 527 (45.5) | |||
| CCI score | |||||||
| 0 | 16 496 (31.9) | 16 647 (32.2) | 0.07 | 15 965 (30.9) | 0.02 | 16 798 (32.5) | 0.08 |
| 1 | 12 091 (23.4) | 12 414 (24.0) | 12 572 (24.4) | 12 614 (24.4) | |||
| 2 | 8497 (16.5) | 8507 (16.5) | 8646 (16.7) | 8485 (16.4) | |||
| ≥3 | 14 554 (28.2) | 8646 (27.3) | 14 455 (27.9) | 13 741 (26.6) | |||
| Frail | 26 311 (50.9) | 26 579 (51.5) | −0.01 | 26 935 (52.2) | −0.03 | 27 429 (53.1) | −0.02 |
| Sex | |||||||
| Female | 34 882 (67.6) | 35 535 (68.8) | −0.01 | 36 069 (69.9) | −0.07 | 36 251 (70.2) | −0.03 |
| Male | 16 756 (32.4) | 16 103 (31.2) | 15 569 (30.1) | 15 387 (29.8) | |||
| Race | |||||||
| Asian | 897 (1.7) | 592 (1.2) | 0.01 | 322 (0.6) | 0.14 | 960 (1.9) | 0 |
| Black | 3217 (6.2) | 1746 (3.4) | 0.03 | 1585 (3.1) | 0.21 | 2171 (4.2) | 0.02 |
| Hispanic | 551 (1.1) | 519 (1.0) | 0 | 662 (1.3) | −0.03 | 836 (1.6) | −0.01 |
| White | 46 054 (89.2) | 48 061 (93.1) | −0.04 | 48 349 (93.6) | −0.22 | 46 830 (90.7) | −0.02 |
| Otherb | 743 (1.4) | 592 (1.2) | 0 | 598 (1.2) | 0.03 | 667 (1.3) | 0 |
| Unknown | 176 (0.3) | 128 (0.3) | 0 | 122 (0.2) | 0.03 | 174 (0.3) | 0 |
| Trauma center proximity | |||||||
| In county | 42 051 (81.4) | 42 103 (81.5) | 0 | 40 961 (79.3) | −0.08 | 41 794 (80.9) | −0.01 |
| Adjacent county | 8012 (15.5) | 8041 (15.6) | 8792 (17.0) | 8254 (16.0) | |||
| No trauma center | 1575 (3.1) | 1494 (2.9) | 1885 (3.7) | 1590 (3.1) | |||
| AIS score ≥3 | |||||||
| Head and neck | 5359 (10.4) | 5315 (10.3) | 0 | 5118 (9.9) | 0.01 | 5225 (10.1) | 0.01 |
| Face | <10c | <10c | 0.01 | <10c | 0 | <10c | 0 |
| Chest | 2634 (5.1) | 2576 (5.0) | 0 | 2566 (5.0) | 0 | 2399 (4.7) | 0.01 |
| Abdomen and pelvis | 343 (0.7) | 269 (0.5) | 0 | 303 (0.6) | −0.01 | 229 (0.4) | 0.01 |
| Extremity | 24 551 (47.5) | 24 507 (47.5) | 0 | 24 714 (47.9) | −0.01 | 24 515 (47.5) | 0 |
| External | 89 (0.2) | 87 (0.2) | 0 | 89 (0.2) | 0.03 | 88 (0.2) | 0.01 |
| Injury subtype | |||||||
| Cervical spine fracture | 733 (1.4) | 733 (1.4) | NA | 733 (1.4) | NA | 733 (1.4) | NA |
| Hip fracture and TBI | 754 (1.5) | 754 (1.5) | NA | 754 (1.5) | NA | 754 (1.5) | NA |
| Isolated fracture | |||||||
| Hip | 23 827 (46.1) | 23 827 (46.1) | NA | 23 827 (46.1) | NA | 23 827 (46.1) | NA |
| Rib | 2327 (4.5) | 2327 (4.5) | NA | 2327 (4.5) | NA | 2327 (4.5) | NA |
| Isolated TBI | 4575 (8.9) | 4575 (8.9) | NA | 4575 (8.9) | NA | 4575 (8.9) | NA |
| Other extremity fractured | 8725 (16.9) | 8725 (16.9) | NA | 8725 (16.9) | NA | 8725 (16.9) | NA |
| Other injurye | 6575 (12.7) | 6575 (12.7) | NA | 6575 (12.7) | NA | 6575 (12.7) | NA |
| Multiple traumas | 4122 (7.9) | 4122 (7.9) | NA | 4122 (7.9) | NA | 4122 (7.9) | NA |
Abbreviations: AIS, Abbreviated Injury Scale; CCI, Charlson Comorbidity Index; NA, not applicable; SMD, standardized mean difference; TBI, traumatic brain injury.
a
SMD compared with Level I trauma center.
b
Other race includes beneficiaries reporting a race category not otherwise listed, including those reporting 2 or more races. Beneficiaries with unknown race are reported separately.
c
Data suppressed because sample size was less than 10.
d
Other extremity fracture includes isolated fractures of the arm or leg other than hip fractures.
e
Other injury includes any National Trauma Data Bank–eligible injury diagnosis not otherwise categorized.