Figure 1.

The workflow of model development. (a) Schematic workflow of the study for training and external validation of a CT image-based DNN model. (b) Flowchart of the proposed two-stage DNN model. The stage I DNN model was used to classify benign and malignant GGNs. The stage II DNN model was used to predict the invasiveness risk of malignant tumors. FUSCC = Fudan University Shanghai Cancer Center. HZCH = Huzhou Central Hospital. TZMH = Taizhou Municipal Hospital. SHPH = Shanghai Pulmonary Hospital.