Table 1.
Comparison of derivation and validation cohorts
| |
Total |
Derivation |
Validation |
|
|---|---|---|---|---|
| Variable* | (n = 4,361) | (n = 2,000) | (n = 2,361) | p-value |
|
Demographics |
|
|
|
|
| Median age |
56.0 (41.0, 71.0) |
56.0 (42.0, 71.0) |
56.0 (41.0, 71.0) |
0.596 |
| Male, no. (%) |
2,422 (55.5%) |
1,104 (55.2%) |
1,318 (55.8%) |
0.680 |
| Caucasian, no. (%), n = 4,220 |
2,608 (61.8%) |
1,193 (61.6%) |
1,415 (62.0%) |
0.765 |
| Admission source, no. (%) n = 4,311 |
|
|
|
0.131 |
| Home |
3,331 (77.3%) |
1,557 (78.8%) |
1,774 (76.0%) |
|
| Nursing facility |
338 (7.8%) |
151 (7.6%) |
187 (8.0%) |
|
| Outside ED |
440 (10.2%) |
183 (9.3%) |
257 (11.0%) |
|
| Other |
202 (4.7%) |
85 (4.3%) |
117 (5.0%) |
|
| APACHE II |
10.0 (6.0, 15.0) |
10.0 (6.0, 15.0) |
10.0 (5.0, 15.0) |
0.770 |
|
Predisposing conditions |
|
|
|
|
| Shock |
395 (9.1%) |
180 (9.0%) |
215 (9.1%) |
0.903 |
| Aspiration |
210 (4.8%) |
92 (4.6%) |
118 (5.0%) |
0.541 |
| Sepsis |
1,806 (41.4%) |
856 (72.8%) |
950 (70.2%) |
0.087 |
| Pancreatitis |
323 (7.4%) |
140 (7.0%) |
183 (7.8%) |
0.345 |
| Pneumonia |
1,227 (28.1%) |
568 (28.4%) |
659 (27.9%) |
0.721 |
| High-risk trauma |
|
|
|
|
| Traumatic brain injury |
490 (11.2%) |
214 (10.7%) |
276 (11.7%) |
0.302 |
| Smoke inhalation |
27 (0.6%) |
10 (0.5%) |
17 (0.7%) |
0.356 |
| Near drowning |
3 (0.1%) |
2 (0.1%) |
1 (0.0%) |
0.597 |
| Lung contusion |
188 (4.3%) |
87 (4.4%) |
101 (4.3%) |
0.907 |
| Multiple fractures |
330 (7.6%) |
141 (7.1%) |
189 (8.0%) |
0.235 |
| High-risk surgery |
|
|
|
|
| Thoracic (noncardiac) |
5 (0.1%) |
3 (0.2%) |
2 (0.2%) |
0.526 |
| Orthopedic spine |
17 (0.4%) |
6 (0.3%) |
11 (0.5%) |
0.381 |
| Acute abdomen |
295 (6.8%) |
133 (6.7%) |
162 (6.9%) |
0.782 |
| Cardiac surgery |
20 (0.5%) |
6 (0.3%) |
14 (0.6%) |
0.154 |
| Aortic vascular |
14 (0.3%) |
5 (0.3%) |
9 (0.4%) |
0.445 |
|
Risk modifiers |
|
|
|
|
| Alcohol abuse |
421 (9.7%) |
191 (9.6%) |
230 (9.7%) |
0.831 |
| Obesity |
1,020 (29.1%) |
456 (28.5%) |
564 (29.6%) |
0.451 |
| Chemotherapy |
158 (3.6%) |
82 (4.1%) |
76 (3.2%) |
0.121 |
| Diabetes mellitus |
1,042 (23.9%) |
485 (24.3%) |
557 (23.6%) |
0.612 |
| Smoking (n = 4019) |
|
|
|
0.892 |
| None |
2,060 (51.3%) |
932 (50.9%) |
1,128 (51.6%) |
|
| Former |
888 (22.1%) |
408 (22.3%) |
480 (22.0%) |
|
| Active |
1,071 (26.7%) |
493 (26.9%) |
578 (26.4%) |
|
| Emergency surgery |
339 (7.7%) |
154 (7.7%) |
185 (7.8%) |
0.868 |
| RR |
20.0 (18.0, 24.0) |
20.0 (18.0, 24.0) |
20.0 (18.0, 24.0) |
0.658 |
| Tachypnea |
315 (7.6%) |
145 (7.6%) |
170 (7.6%) |
0.948 |
| SpO2 |
95.6 (95.4, 95.7) |
95.2 (95.2, 95.7) |
95.7 (95.5, 95.9) |
0.068 |
| SpO2 > 95% |
2,662 (62.3%) |
1,203 (61.4%) |
1,459 (63.1%) |
0.254 |
| FiO2 |
0.2 (0.2, 0.3) |
0.2 (0.2, 0.3) |
0.2 (0.2, 0.3) |
0.561 |
| FiO2 > 0.35, no. (%) |
841 (19.3%) |
381 (19.1%) |
452 (19.1%) |
0.937 |
| Albumin level |
3.5 (2.9, 4.0) |
3.5 (3.0, 4.0) |
3.5 (2.9, 4.0) |
0.068 |
| Hypoalbuminemia |
945 (47.1%) |
414 (45.4%) |
531 (48.5%) |
0.167 |
| pH median |
7.4 (7.3, 7.4) |
7.4 (7.3, 7.4) |
7.4 (7.3, 7.4) |
0.632 |
| Acidosis (pH <7.35) |
476 (45.9%) |
206 (43.6%) |
270 (47.8%) |
0.173 |
|
Outcome |
|
|
|
|
| ALI/ARDS | 303 (7.0%) | 127 (6.4%) | 176 (7.5%) | 0.153 |