Clinical features and risk factors of severely and critically ill patients with COVID-19

Table 3 Logistic regression results of potential risk factors for severity of coronavirus disease 2019

	Wald χ2	P value	OR	95%CI
				Upper bound	Lower bound
Intercept (Moderate)	1.800	0.180	9.816	-	-
Intercept (Severe)	1.122	0.289	0.179	-	-
Age	5.477	0.019	1.055	1.009	1.104
High-sensitivity cardiac troponin I
Normal (≤ 15.61, ≤ 34.22)
Higher (> 15.61, > 34.22)	4.094	0.043	4.019	1.045	15.467
Neutrophil to lymphocyte ratio
Higher (> 3.13)	5.477	0.042	10.126	1.088	94.247
Normal (≤ 3.13)

¹The normal and abnormal range applied to female patients.

²The normal and abnormal range applied to male patients.

Ordinal logistic regression model was adopted in JMP15.0 software to explore the risk factors associated with severity of coronavirus disease 2019 patients. Step-by-step regression method (P for inclusion = 0.05, P for exclusion = 0.05) was applied and 3 variables were included in the final model. Results showed that total model test χ² = 17.380, P < 0.001, which means at least one β in the equation did not equal to 0 and this model was preceded to constant 1. Good-to-fitness test showed χ² = 59.137, P = 0.968 > 0.05, which means this model fit well. OR: Odds ratio.