Fig. 3

The receiver operating characteristic curves (A-C), calibration curve (D-F) and decision curves (G-I) of different models in the training cohort, external validation cohort 1, and external validation cohort 2, respectively. The morphological model incorporates sphericity, major axis length and maximum 2D diameter (row). The nomogram model-1 integrates hormone receptor, human epidermal growth factor receptor-2, and global FD. The nomogram model-2 integrates hormone receptor, human epidermal growth factor receptor-2, sphericity, major axis length and maximum 2D diameter (row). The nomogram model-1 showed the best performance in predicting pCR to NAC. AUC = area under the receiver operating characteristic curve, CI = confidence interval, FD = fractal dimension