Table 1 Baseline characteristics of individuals by cohorts
Characteristics | Training cohort | Internal validation cohort | External validation cohort |
|---|---|---|---|
(N = 111) | (N = 111) | (N = 228) | |
Demographics | |||
 Age, years | 62 (54.5-72) | 64 (52-70.5) | 63 (50-70) |
 Sex | |||
  Female | 65 (58.56%) | 53 (47.75%) | 116 (50.88%) |
  Male | 46 (41.44%) | 58 (52.25%) | 112 (49.12%) |
Clinical characteristics | |||
 Comorbidity number | 1 (0-2) | 1 (1-2) | 1 (0-2) |
 Comorbidity | |||
  Hypertension | 40 (36.04%) | 52 (46.85%) | 86 (37.72%) |
  Diabetes | 21 (18.92%) | 26 (23.42%) | 41 (17.98%) |
  Coronary heart disease | 6 (5.41%) | 12 (10.81%) | 16 (7.02%) |
  Tumor | 8 (7.21%) | 12 (10.81%) | 17 (7.46%) |
  COPD | 1 (0.9%) | 2 (1.8%) | 2 (0.88%) |
Symptoms at admission | |||
 Fever | 97 (87.39%) | 90 (81.08%) | 166 (72.81%) |
 Temp (max) ≥ 39 °C | 28 (25.23%) | 24 (21.62%) | 45 (19.74%) |
 Cough | 78 (70.27%) | 79 (71.17%) | 170 (74.56%) |
 Dyspnea | 56 (50.45%) | 51 (45.95%) | 88 (38.6%) |
 Sputum | 44 (39.64%) | 49 (44.14%) | 108 (47.37%) |
 Fatigue | 48 (43.24%) | 49 (44.14%) | 56 (24.56%) |
 Diarrhea | 31 (27.93%) | 34 (30.63%) | 35 (15.35%) |
 Myalgia | 23 (20.72%) | 36 (32.43%) | 34 (14.91%) |
 Nausea or vomiting | 3 (2.7%) | 7 (6.31%) | 2 (0.88%) |
Vital status | |||
 Critical illness | 12 (10.81%) | 16 (14.41%) | 25 (10.96%) |
 Noncritical illness | 99 (89.19%) | 95 (85.59%) | 203 (89.04%) |
Follow-up | |||
 Time to critical illness, days | 25 (14.5-34) | 25 (10-30.5) | 18.5 (11.75-30.25) |