Fig. 3

Construction and model diagnosis of prognostic nomogram. The prognostic nomogram was constructed based on the multivariate Cox model including CEA, which could predict the 3-week and 5-week overall survival probability of COVID-19 patients (A). The significant prognostic factors in multivariate Cox model were marked with asterisks (*) in the nomogram (*: P < 0.05; **: P < 0.01). The time-related ROC curve suggested acceptable discrimination of the nomogram (B). Besides, the risk score (RS) was calculated by the formula generated by the multivariate Cox model. Kaplan–Meier curve suggested the prognostic value of the RS (C, P < 0.001). Eventually, in univariate (HR = 4.105, 95% CI (2.140 − 7.874), P < 0.001) (D) and multivariate (HR = 1.053, 95% CI (1.026 − 1.082), P < 0.001) (E) Cox regression model corrected by demographics, the RS was shown to be an independent prognostic indicator for COVID-19 patients