Fig. 4From: A nomogram for predicting pathological complete response in patients with human epidermal growth factor receptor 2 negative breast cancerValidation of the Nomogram. a Internal validation using receiver operating characteristic (ROC) curve. The area under the ROC curve (AUC) is 0.779, 95 % confidence intervals (CI): 0.718–0.839. b External validation using ROC. The AUC is 0.703, 95 % CI: 0.622–0.780Back to article page