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Table 1 Characteristics of the development and test cohorts

From: Predicting clinical outcomes among hospitalized COVID-19 patients using both local and published models

Characteristics

Development cohort (N = 309)

Test cohort (N = 207)

P

Missing Data

Missing Data

Outcome variables(N, (%))

       

Mortality

38

(12.3)

 

21

(10.1)

 

0.45

Criticality

80

(25.9)

 

46

(22.2)

 

0.34

Demographics

       

Age (Mean, (SD))

56.5

(16.0)

 

53.3

(18.5)

 

0.008*

Female (%)

49.8

  

48.3

  

0.73

Race (N (%))

  

1%

  

1.4%

0.22

African American

152

(49.2)

 

86

(41.5)

  

Hispanic

37

(12)

 

25

(12.1)

  

Other, Non- Hispanic

94

(30.4)

 

82

(39.6)

  

White

23

(7.4)

 

11

(5.3)

  

Vital signs on admission (mean (SD))

       

Systolic blood pressure

135

(25)

 

134

(24.7)

 

0.80

Diastolic blood pressure

78.3

(15)

 

77.9

(14.3)

 

0.92

Hearth rate

102

(21)

 

97.1

(20.1)

 

0.70

Respiratory rate

23.6

(6.9)

 

22.7

(6.6)

 

0.52

Temperature

37.5

(1.1)

 

37.2

(1.0)

 

0.095

Oxygen saturation

93.4

(7.5)

 

97.7

(62.4)

 

0.16

Clinical and radiological features

       

BMI, mean (SD)

32.3

(10.5)

 

32.0

(9.6)

 

0.56

GCS, mean (SD)

14.9

(0.8)

0%

14.8

(1.2)

1%

0.28

Dyspnea (N (%))

125

(40.5)

 

90

(43.5)

 

0.49

Coma (N (%))

3

(1)

 

1

(0.5)

 

0.54

Pregnant (N (%))

10

(3.2)

 

14

(6.8)

 

0.062

Abnormal chest X-ray (N (%))

228

(75)

1.9%

136

(74)

10.6%**

0.67

Laboratory findings (mean, (SD)

       

White blood cells

6.8

(3.1)

0%

7.7

(3.9)

1%

0.001*

Neutrophiles

5.2

(3.6)

0%

5.6

(3.7)

3.4%

0.038*

Lymphocytes

1.1

(0.7)

0%

1.3

(1)

3.4%

0.024*

Hemoglobin

13.0

(2.2)

0%

12.7

(2.3)

1%

0.57

Hematocrit

39.4

(6.3)

0%

37.9

(6.8)

1%

0.36

RDW

14.9

(2)

0%

15.1

(2.2)

1%

0.68

Platelets

215

(91)

0%

236

(105)

1%

0.15

Creatinine

1.8

(3)

0%

1.9

(2.6)

2.4%

0.47

Lactic acid

1.6

(1.6)

23.3%

1.8

(1.9)

30.4%

0.11

Lactate dehydrogenase

353

(227)

16.5%

386

(521)

27.5%**

0.14

Pro-calcitonin

1.4

(6.7)

16.8%

2.2

(10.4)

32.9%**

0.12

Troponin I

0.11

(0.8)

32.4%

0.04

(0.1)

31.4%

0.076

B-type natriuretic peptide

527

(1939)

57%

369

(664)

63.8%

0.10

Albumin

3.7

(0.5)

3.9%

3.6

(0.6)

7.2%

0.009*

ALT

38.8

(44.4)

3.9%

37.8

(49.9)

7.2%

0.88

AST

48.2

(58.3)

3.9%

52.3

(81.3)

7.2%

0.20

Total bilirubin

0.7

(0.9)

3.9%

0.8

(0.7)

7.2%

0.76

Direct bilirubin

0.2

(0.5)

3.9%

0.2

(0.3)

7.2%

0.57

Creatine kinase

281

(471)

63.8%

3071+

(22,782)

67.6%

0.012*

C-reactive protein

101

(84)

15.5%

98.6

(86.7)

19.8%

0.46

Interleukin 6

24.9

(33.9)

75.1%

28.1

(40.2)

87.9%**

0.17

D-dimer

1.9

(2.6)

40.8%

2.2

(3)

27.5%**

0.46

Ferritin

884

(1562)

7.1%

930

(1360)

17.4%**

0.45

Medical condition

       

Hypertension

178

(57.6)

 

111

(53.6)

 

0.37

Heart disease

94

(30)

 

56

(27)

 

0.41

Stroke

23

(7.4)

 

11

(5.3)

 

0.34

Diabetes

161

(52.1)

 

96

(46)

 

0.20

Asthma

65

(21)

 

45

(22)

 

0.85

COPD

24

(7.8)

 

13

(6.3)

 

0.52

Chronic kidney disease

52

(17)

 

38

(18)

 

0.65

End-stage renal disease

30

(9.7)

 

24

(12)

 

0.49

Cancer

33

(11)

 

23

(11)

 

0.88

Transplant

1

(0.3)

 

1

(0.5)

 

0.78

Human immunodeficiency virus

7

(2.3)

 

1

(0.5)

 

0.11

Immunosuppression

2

(0.6)

 

9

(4.3)

 

0.004*

Sickle cell disease

6

(2)

 

6

(2.9)

 

0.48

Nicotine use

34

(11)

 

32

(16)

 

0.14

Alcohol use

59

(19)

 

45

(22)

 

0.46

Substance use

16

(5)

 

11

(5.3)

 

0.95

Variables needed for external models only

       

Blood urea nitrogen, mean (SD)

   

23.5

(20.7)

1.9%

 

eGFR, mean (SD)

   

70.9

(40.6)

2.4%

 

Partial thromboplastin time, mean (SD)

   

34.4

(6.5)

42.5%

 
  1. ALT, alanine aminotransferase; AST, aspartate aminotransferase; BMI, body mass index; COPD, chronic obstructive pulmonary disease; eGFR, estimated glomerular filtration rate; GCS, Glasgow coma scale; RDW, red blood cell distribution width; SD, standard deviation
  2. *Continuous variables were compared using a t-test and categorical variables, including missingness, were compared using a Chi-square test
  3. **P < 0.05 using a chi-square test, development versus test cohort
  4. Significance was set at 0.05
  5. +A single very high, but clinically consistent creatine kinase accounted for the very large mean in this group
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