TABLE 1

Demographics and Characteristics of the Study Population

VariableOverall Population (n = 71 377)Pneumonia (n = 1818)No Pneumonia (n = 69 559)Pa
Sex, n (%)
 Female24 448 (34.3)518 (28.5)23 930 (34.4)<.0001
 Male46 885 (65.7)1300 (71.5)45 585 (65.6)
Age, n (%)
 0–517 643 (24.7)220 (12.1)17 423 (25.1)<.0001
 6–108524 (11.9)140 (7.7)8384 (12.1)
 11–1515 959 (22.4)316 (17.4)15 643 (22.5)
 16–1829 251 (41.0)1142 (62.8)28 109 (40.4)
Race/ethnicity, n (%)
 White37 280 (52.2)1039 (57.2)36 241 (52.1).0007
 African American14 508 (20.3)332 (18.3)14 176 (20.4)
 Hispanic12 380 (17.3)293 (16.1)12 087 (17.4)
 Asian1264 (1.8)28 (1.5)1236 (1.8)
 Other/unknown5945 (8.3)126 (6.9)5819 (8.4)
Injury region, n (%)
 Multisite with head and neck29 056 (40.7)1255 (69.0)27 801 (40.0)<.0001
 Multisite without head and neck13 170 (18.5)200 (11.0)12 970 (18.7)
 Isolated head and neck29 151 (40.8)363 (20.0)28 788 (41.4)
Injury mechanism n (%)
 MVC31 232 (43.8)1128 (62.1)30 104 (43.3)<.0001
 Pulmonary951 (1.3)40 (2.2)911 (1.3)
 Fall12 639 (17.7)144 (7.9)12 495 (18.0)
 Firearm3509 (4.9)164 (9.0)3345 (4.8)
 Blunt trauma6014 (8.4)63 (3.5)5951 (8.6)
 Other/unspecified17 032 (23.9)279 (15.4)16 753 (24.1)
ISS
 Mean (SD)12.1 (9.9)26.6 (12.6)11.8 (9.6)<.0001
 Median (IQR)10 (5–17)26 (17–34)10 (5–17)
 <16, n (%)41 469 (64.3)162 (11.0)41 307 (65.5)<.0001
 ≥16, n (%)23 074 (35.8)1317 (89.1)21 757 (34.5)
GCS score
 Mean (SD)13.3 (3.6)7.4 (4.8)13.4 (3.4)<.0001
 Median (IQR)15 (14–15)6 (3–12)15 (14–15)
 <8, n (%)6446 (11.1)989 (61.3)5457 (9.7)<.0001
 ≥8, n (%)51 422 (88.9)624 (38.7)50 798 (90.3)
LOS (d)
 Mean (SD)6.0 (8.4)24.2 (18.6)5.5 (7.4)<.0001
 Median (IQR)3 (2–6)20 (13–31)3 (2–6)
Intensive care days
 Mean (SD)2.5 (5.8)16.7 (13.9)2.1 (4.9)<.0001
 % with days49.788.718.0
Ventilation days
 Mean (SD)1.2 (4.4)12.4 (12.1)0.9 (3.5)<.0001
 % with days19.997.048.4
Comorbidities, n (%)
 061 074 (85.6)1451 (79.8)59 623 (85.7)<.0001
 ≥110 303 (14.4)367 (20.2)9936 (14.3)
  • IQR, interquartile range.

  • a P value from t test (continuous variables) or χ2 (categorical variables).