ROMO1 and rheumatoid arthritis: In RA, ROMO1 showed exceptional performance: the training set (GSE56649) achieved an AUC of 0.991 (95% CI: 0.968-1.000), validation set 1 (GSE15573) reached 0.781 (95% CI: 0.620–0.943), and validation set 2 (GSE205962) attained a perfect 1.000 (95% CI: 1.000–1.000), demonstrating high diagnostic accuracy and good generalizability(Fig. 5A).