Development and Validation of the RCOS Prognostic Index: A Bedside Multivariable Logistic Regression Model to Predict Hypoxaemia or Death in Patients with SARS-CoV-2 Infection

Table 1

Characteristics of patients in the development and the validation cohorts.

	Development cohort		Validation cohort
	Median (IQR) or no (%)	Missing	Median (IQR) or no (%)	Missing
Age (years)	48 (34–60)	9	47 (33–58)	0
Systolic BP (mm Hg)	120 (110–120)	1111	120 (110–120)	4
Diastolic BP (mm Hg)	80 (70–80)	1111	80 (70–80)	4
Heart rate (min)	88 (82–92)	1112	86 (80–90)	5
Respiratory rate (min)	20 (20–22)	1117	20 (20–22)	5
Temperature (°F)	99 (99–99)	1110	99 (98–99)	5
AST (IU/L)	25 (18–36)	16	22 (17–31)	3
ALT (IU/L)	27 (18–42)	18	26 (18–40)	3
Albumin (g/dL)	4.5 (4.2–4.8)	18	4.6 (4.3–4.9)	3
LDH (IU/L)	385 (269–495)	7	375 (284–467)	1
Creatinine (mg/dL)	0.8 (0.7–1)	6	0.7 (0.6–0.8)	3
Urea (mg/dL)	22 (17–29)	7	22 (18–29)	3
C-reactive protein (mg/dL)	0.5 (0.2–3)	5	0.5 (0.3–2.8)	1
Sodium (mmol/L)	141 (139–143)	5	141 (139–143)	3
Haemoglobin (g/dL)	13 (12–14)	82	13 (12–14)	0
Platelet count (×10^9/L)	265 (207–333)	82	304 (243–364)	0
White cell count (×10^9/L)	7 (5.5–9.1)	82	6.9 (5.4–9)	0
Neutrophil count (×10^9/L)	4.5 (3.3–6.2)	82	4.4 (3.3–6.2)	0
Lymphocyte count (×10^9/L)	1.9 (1.4–2.6)	82	1.9 (1.4–2.4)	0
Neutrophil/Lymphocyte ratio	2.3 (1.6–3.7)	82	2.3 (1.6–3.8)	0
Female gender	1593 (39.5)	0	752 (36.8)	0
Deaths	172 (4.3)	0	53 (2.6)	0
Hypoxaemia	959 (23.8)	0	545 (26.6)	0

IQR, interquartile range; BP, blood pressure; ALT, alanine transaminase; AST, aspartate transaminase; LDH, lactate dehydrogenase.