Figure 3. Receiver operating characteristic (ROC) curve was performed to evaluate the threshold value of TGF-β1 in differentiating malignant from benign pulmonary diseases.

TGF-β1 reached a sensitivity of 62.2%, a specificity of 60.6%, a positive predictive value of 67.5%, and a negative predictive value of 52.6% (cut-off value: 10.85 pg/ml; area under the curve: 0.695).