Nomogram contruction and Cox regression analysis
REGRESSION
In order to construct, 70% of patients were randomly allocated to the training cohort (n = 787) and 30% to the validation cohort (n = 338). We applied with univariate Cox regression to identify relevant prognostic factors, subsequent to multivariate Cox regression to determine independent risk factors in the training set. Hazard ratios (HR) and 95% confidence intervals (CI) were simultaneously recorded during this analysis. The nomogram was constructed based on a Cox regression model to identify significant variables for determining the 3-, 5-, and 8-year OS rates in patients with CVC.Through the allocation of weights to each variable, multiple lines are created, with each variable corresponding to a specific point. Through the cumulative sum of points assigned to all variables, an overall score is obtained, which can be used to predict survival rates at different points in time.