GPR183 and rheumatoid arthritis: For diagnostic value, the AUCs of FAS, GPR183, and TFRC for RA vs. HC group were 0.9199, 0.9605, and 0.9605, respectively (Figure 5(b)), while the AUCs of FAS, GPR183, and TFRC were 0.8914, 0.8532, and 0.8203 in RA vs. OA group (Figure 5(c)).