Table 2 summarizes the clinicopathological variables of the case and control groups. Our clinical validation trial demonstrated that the results of the analysis were broadly similar to those of the main bioinformatic analysis. The expression levels of IGF1 (p = 0.0002), RET (p = 0.0021), and IGFBP2 (p = 0.012) were significantly higher in IPF blood samples than in normal blood samples, while those of CDKN2A, JUN, and TFAP2A (p values are all greater than 0.05) were comparable between the two groups (Figure 9). This evidence concerns the gene CDKN2A and idiopathic pulmonary fibrosis.