Figure 4. Independent prognostic analysis of the four-gene model. (A) Univariate and multivariate Cox regression analysis of the risk score and clinicopathological characteristics in the training set. (B) Univariate and Multivariate Cox regression analysis of the risk score and clinicopathological characteristics in the validation set. (C) A nomogram for prognostic prediction based on risk score and other clinicopathological factors in patients with LUSC. (D) Calibration curve for evaluating the predictive accuracy of the prognostic model.