Fig. 3

The performance of the BLDM model comparison with ACR TI-RADS. Receiver operating characteristic (ROC) curves of the BLDM model, showcasing its performance in the discovery cohort (A), a validation cohort and an independent test cohort, respectively (B). The area under the curve (AUC) scores are presented, along with 95% confidence interval values. C Methylation scores assigned to TN specimens in the validation cohort and independent test cohort. A threshold of 0.51 was set to distinguish between MTNs and BTNs. D A comparison of the sensitivity and specificity of US and the BLDM model in predicting MTNs. E The PPV and NPV of US and the BLDM model. Sample numbers in each category are presented at the bottom of the chart. F The diagnostic performance of the BLDM model specifically in BTN patients with ACR TI-RADS category ≥ 4 in the validation cohort and independent test cohort. BTN, benign thyroid nodule; MTN, malignant thyroid nodule; TN, thyroid nodule; US, ultrasonography; TP, true positive; FP, false positive; TN, true negative; FN, false negative; PPV, positive predictive value; NPV, negative predictive value