Table 2.
Patient cohort summary. We provide a summary of the patient cohort characteristics across the training, validation, and test sets. This includes the patient demographics, distributions of input features, and the prevalence of the deterioration labels across the different time windows.
| Characteristic | Training set | Validation set | Test set | |||||||
| Cohort demographics | ||||||||||
|
|
Patients (n=16,901), n (%) | 11,830 (70) | 3397 (20.1) | 1674 (9.9) | ||||||
|
|
|
Male patientsa | 7056 (59.6) | 2044 (60.2) | 972 (58.1) | |||||
|
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Encounters (n=26,073), n (%) | 18,319 (70.3) | 5206 (20) | 2548 (9.8) | ||||||
|
|
|
Age group (years), mean (SD) | 55.3 (19.3) | 54.9 (18.7) | 53.6 (19.1) | |||||
|
|
|
|
<40, n (%)b | 4843 (26.4) | 1371 (26.3) | 672 (26.4) | ||||
|
|
|
|
40-59, n (%)b | 5313 (29) | 1506 (28.9) | 728 (28.6) | ||||
|
|
|
|
≥60, n (%)b | 8163 (44.6) | 2329 (44.7) | 1148 (45.1) | ||||
|
|
|
Encounters with composite outcome, n (%)b | 3979 (21.7) | 1144 (22) | 549 (21.5) | |||||
|
|
|
Encounters during the COVID-19 pandemic, n (%)b | 5594 (30.5) | 1657 (31.8) | 836 (32.8) | |||||
| Observation sets (n=951,591), n (%) | 673,041 (70.7) | 182,795 (19.2) | 95,755 (10.1) | |||||||
|
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Heart rate (beats/min), mean (SD; IQR) | 78 (15.9; 68-90) | 78 (16.3; 68-89) | 79 (15.8; 70-89) | ||||||
|
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Respiratory rate (breaths/min), mean (SD; IQR) | 18 (2.8; 18-20) | 18 (2.9; 18-20) | 18 (2.9; 18-20) | ||||||
|
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Systolic blood pressure (mm Hg), mean (SD; IQR) | 122 (20.9; 109-137) | 124 (21.6; 110-139) | 122 (20.2; 109-136) | ||||||
|
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Temperature (°C), mean (SD; IQR) | 36.7 (0.4; 36.5-36.9) | 36.7 (0.5; 36.5-36.9) | 36.7 (0.4; 36.5-36.9) | ||||||
|
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Oxygen saturation (%), (SD; IQR) | 99 (2.0; 97-100) | 99 (2.0; 97-100) | 99 (2.1; 97-100) | ||||||
|
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Level of consciousness, n (%)c | |||||||||
|
|
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Alert | 537,853 (98.1) | 144,014 (97.9) | 76,376 (97.5) | |||||
|
|
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Voice, pain, or unresponsive | 10,685 (1.9) | 3086 (2.1) | 1940 (2.5) | |||||
|
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Supplementary oxygen, n (%)d | |||||||||
|
|
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Provided | 15,201 (2.3) | 3332 (1.8) | 2086 (2.2) | |||||
|
|
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Not provided | 657,840 (97.7) | 179,463 (98.2) | 93,669 (97.8) | |||||
|
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Deterioration, n | |||||||||
|
|
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Within 36 hours | 36,760 | 10,681 | 5373 | |||||
|
|
|
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Death | 1100 | 266 | 154 | ||||
|
|
|
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ICUe admission | 36,255 | 10,571 | 5319 | ||||
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Within 24 hours | 31,431 | 9306 | 4556 | |||||
|
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|
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Death | 715 | 127 | 71 | ||||
|
|
|
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ICU admission | 31,088 | 9233 | 4521 | ||||
|
|
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Within 12 hours | 25,382 | 7633 | 3658 | |||||
|
|
|
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Death | 358 | 70 | 21 | ||||
|
|
|
|
ICU admission | 25,199 | 7589 | 3643 | ||||
|
|
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Within 6 hours | 21,332 | 6476 | 2987 | |||||
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|
|
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Death | 166 | 37 | 9 | ||||
|
|
|
|
ICU admission | 21,227 | 6452 | 2979 | ||||
aTraining set: n=11,830; validation set: n=3397; test set: n=1674.
bTraining set: n=18,319; validation set: n=5206; test set: n=2548.
cTraining set: n=548,538; validation set: n=147,100; test set: n=78,316.
dTraining set: n=673,041; validation set: n=182,795; test set: n=95,755.
eICU: intensive care unit.