Table 1 Patient characteristics of the training/validation cohorts

COVID-19 WHO Score 6–8 (ICU/death)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

 3 days

1276

163 (12.8%)

633

109 (17.2%)

411

120 (29.0%)

988

289 (29.3%)

190

32 (16.8%)

2815

58 (2.1%)

1037

169 (16.3%)

163

27 (16.3%)

 14 days

1276

389 (30.5%)

633

223 (35.2%)

411

171 (42.0%)

988

391 (39.6%)

190

56 (29.5%)

2815

118 (4.2%)

1037

310 (29.9%)

163

39 (23.9%)

Demographics

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

 Age (median [IQR])

1276

71.5 [57.1, 82.6]

633

73.0 [56.0, 84.0]

411

66.0 [53.0, 79.0]

988

59.0 [46.0,75.0]

190

73.5 [59.3, 82.0]

2815

60.0 [50.0, 68.0]

1037

70.0 [57.0, 82.0]

163

60.0 [48.0–74.0]

 Sex (male)

1276

742 (58.2%)

633

364 (57.5%)

411

252 (61.0%)

988

581 (58.8%)

190

120 (63.1%)

2815

1437 (51.0%)

1037

573 (55.3%)

163

95 (58.3%)

 Non-White ethnicity

960

379 (39.5%)

546

55 (10.0%)

390

156 (40.0%)

817

607 (74.3%)

190

46 (24.2%)

2815

2815 (100.0%)

892

306 (34.3%)

–

–

Comorbidities

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

N avail.

N (%)

 Hypertension

1276

695 (54.5%)

633

321 (50.7%)

411

172 (42.0%)

988

309 (31.3%)

190

117 (61.6%)

2815

821 (29.2%)

1037

637 [61.4%)

163

55 (33.7%)

 Diabetes mellitus

1276

439 (34.4%)

633

163 (25.8%)

411

105 (26.0%)

988

286 (28.9%)

190

71 (37.4%)

2815

371 (13.2%)

1037

358 (34.5%)

163

27 (16.6%)

 Heart failure

1276

117 (9.2%)

633

137 (21.6%)

410

–

988

52 (5.3%)

190

33 (17.4%)

2815

236 (8.4%)²

1037

178 (17.2%)

163

15 (9.2%)

 Ischaemic heart diseases

1276

185 (14.5%)

633

152 (24.0%)

409

108 (26.0%)¹

–

–

190

52 (27.4%)

–

–

1037

245 (23.6%)

163

21 (12.9%)

 COPD

1276

141 (11.1%)

633

115 (18.2%)

409

27 (6.6%)

988

64 (6.5%)

190

41 (21.6%)

2815

17 (0.6%)

1037

152 (14.7%)

–

–

 Asthma

1276

174 (13.6%)

633

112 (17.7%)

409

41 (10.0%)

988

85 (8.6%)

190

27 (14.2%)

–

–

1037

169 (16.3%)

–

–

 Chronic kidney disease

1276

234 (18.3%)

633

111 (17.5%)

410

40 (9.8%)

988

110 (11.1%)

190

59 (31.1%)

2815

56 (2.0%)

1037

274 (26.4%)

163

9 (5.5%)

Blood biomarker

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

 Albumin (g/L)

1153

37.0 [33.0, 40.0]

501

32.0 [29.0, 36.0]

390

38.0 [35.0, 42.0]

863

36.0 [31.0, 40.0]

190

30.0 [27.0, 33.0]

2404

38.1 [35.1, 40.5]

993

32.0 [28.0, 35.0]

120

39.0 [36.0–43.0]

 C-reactive protein (CRP, mg/L)

1240

80.0 [36.0, 141.6]

545

75.0 [25.0, 150.0]

403

97.0 [45.0, 179.0]

974

76.5 [25.0, 153.8]

190

77.0 [36.3, 138.3]

2393

2.3 [0.8, 9.0]

970

89.0 [33.2, 157.0]

163

48.0 [16.0–113.0]

 Urea (mmol/L)

1221

7.1 [4.6, 11.7]

563

6.95 [4.8, 10.6]

375

6.0 [4.0, 9.4]

489

7.4 [4.6, 12.5]

–

–

–

–

1018

6.8 [4.6, 11.8]

154

5.5 [4.3–7.5]

 Estimated GFR

1254

65.0 [41.0, 86.0]

377

62.0 [40.0, 81.0]

407

77.0 [54.0, 96.0]

965

74.0 [49.0, 100.0]

190

68.0 [43.3. 88.0]

2433

103.1 [88.2, 117.5]

757

54.0 [29.0, 72.0]

163

84.0 [57.0–99.0]

 Haemoglobin (g/L)

1223

127.0 [112.0, 141.0]

561

128.0 [111.0, 143.0]

410

130.0 [112.0, 143.0]

987

125.0 [108.0, 139.0]

190

129.0 [110.0, 141.0]

2584

124.0 [113.0, 135.0]

1009

130.0 [113.0, 144.0]

163

139.0 [129.0–148.0]

 Lymphocyte count (× 10⁹/L)

1221

0.9 [0.7, 1.3]

561

1.0 [0.7, 1.4]

410

0.9 [0.6, 1.4]

987

0.9 [0.6, 1.3]

190

0.9 [0.6, 1.2]

2584

1.5 [1.1, 1.9]

1011

0.9 [0.7, 1.4]

153

1.1 [0.8–1.5]

 Neutrophil count (× 10⁹/L)

1220

5.4 [3.8, 7.7]

560

5.8 [4.2, 8.8]

410

5.9 [3.9, 8.2]

986

5.0 [3.5, 8.1]

190

5.2 [3.5, 7.4]

2584

3.5 [2.7, 4.7]

1011

5.5 [3.8, 8.2]

153

4.4 [3.0–7.1]

 Neutrophil/lymphocyte ratio

1218

5.6 [3.4, 9.5]

559

5.8 [3.4, 10]

410

6.0 [4.0, 10.0]

986

5.6 [3.2, 10.1]

190

5.7 [3.6, 9.8]

2584

2.3 [1.7, 3.5]

1011

5.6 [3.2, 10.2]

153

4.3 [2.4–7.7]

 Lymphocyte/CRP ratio

1196

1.2 [0.6, 3.2]

559

1.3 [0.5, 4.6]

402

1.0 [0.4, 2.4]

0.0 [0.0, 0.0]

190

1.1 [0.5, 2.7]

2362

0.7 [0.1, 2.0]

962

1.1 [0.5, 3.3]

–

–

 Platelet count (× 10⁹/L)

1224

213.0 [161.8, 274.0]

560

231 [176.8, 303.5]

409

221.0 [169.0, 280.0]

986

209.0 [161.0, 275.8]

190

207.5 [150.3, 268.5]

2584

223.0 [179.8, 273.0]

1008

218.0 [165.0, 287.2]

163

205.0 [160.0–279.0]

Physiological parameters

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

N avail.

Median [IQR]

 NEWS2 Total Score

1262

2.0 [1.0, 4.0]

529

3.0 [2.0, 5.0]

404

5.0 [3.0, 7.0]

744

3.0 [1.0, 5.0]

190

3.0 [2.0, 5.0]

2804

1.0 [0.0, 3.0]

1019

4.0 [2.0, 7.0]

163

5.0 [3.0–7.0]

 Heart rate

1273

85.0 [75.0, 94.0]

560

90.5 [82.0, 102.0]

410

94.0 [81.0, 107.0]

752

85.0 [75.0, 95.0]

190

82.0 [71.0, 95.0]

2812

81.0 [76.9, 85.8]

1028

90.0 [79.0, 104.0]

160

89.5 [75.3–100.8]

 Oxygen saturation

1273

96.0 [95.0, 98.0]

561

97.0 [96.0, 99.0]

410

96.0 [94.0, 98.0]

712

96.0 [95.0, 97.0]

190

95.0 [94.0, 96.0]

2797

97.8 [97.0, 98.2]

1029

96.0 [94.0, 98.0]

163

95.0 [92.0–97.0]

 Oxygen flow rate (L/min)

1271

0.0 [0.0, 4.0]

260

3.0 [2.0, 8.0]

403

2.0 [0.0, 10.0]

978

0.0 [0.0, 0.0]

190

2.0 [0.0, 3.0]

–

–

1017

0.0 [0.0, 4.0]

125

1.0 [0.0–2.0]

 Respiration rate

1273

19.0 [18.0, 21.0]

561

20.0 [19.0, 24.0]

410

24.0 [20.0, 28.0]

755

19.0 [18.0, 22.0]

190

20.0 [18.0, 21.0]

2811

20.0 [19.0, 21.0]

1020

20.0 [18.0, 25.0]

160

24.0 [20.0–28.0]

 Systolic blood pressure

1273

125.0 [112.0, 139.0]

555

137.0 [123.0, 152.0]

411

131.0 [115.0, 143.0]

751

125.0 [115.0, 140.0]

190

123.0 [111.0, 140.8]

1431

120.0 [110.0, 128.0]

1022

128.0 [113.0, 144.0]

160

129 [116.0–142.8]

 Diastolic blood pressure

1273

71.0 [62.0, 80.0]

555

78.0 [70.0, 85.0]

411

73.0 [64.0, 81.0]

751

74.0 [66.0, 81.0]

190

72.0 [64.3, 82.0]

1433

71.0 [65.0, 78.0]

1022

75.0 [67.0, 84.0]

160

77.0 [69.0–87.0]

 Temperature

1273

36.9 [36.6, 37.4]

558

36.9 [36.7, 37.5]

410

37.3 [36.8, 38.1]

750

36.9 [36.4, 37.5]

190

37.2 [36.7, 37.9]

2815

36.5 [36.3, 36.7]

1029

36.8 [36.2, 37.5]

162

37.2 [36.5–38.3]