Assuming 95% specificity in the training set, 1309.45 ng/mL was appropriate as the cut‐off value of CTAPIII/CXCL7 in NSCLC diagnosis (training set: sensitivity 42.3%, specificity 95%; test set: sensitivity 45.9%, specificity 96.1%). The gene discussed is PPBP; the disease is non-small cell lung carcinoma.