Fig. 3

Cox regression model of OS and its effect verification. a: Univariate Cox risk proportional regression model for analysis of various indicators. b: The best subset selection function filters the indicators for the multivariate Cox risk proportional regression model. c: Multivariate Cox risk proportional regression model on the selected indicators. d: Multivariate Cox risk proportional regression model with nomogram visualization. e: Calibration plot evaluation of the multivariate Cox risk proportional regression model prediction effect