Table 3.

Diagnostic value of ACPA and anti-carbVIMIgM assays using Receiver Operating Characteristic Curve analysis

Assay, area under curve (confidence interval)	Cutoff (U/mL)	Se	Sp	PPV	NPV	YI
Anti-carbVIMIgM, 0.9111 (0.8722–0.9501)	20	85.2	90.1	89.6	85.9	0.75
	30	78.2	96.3	96.3	81.8	0.75
	40	59.4	100	100	71.7	0.59
Anti-MCV IgG, 0.8479 (0.7959–0.8999)	20	86.1	75.3	77.7	84.4	0.61
	30	68.3	87.1	84.1	73.3	0.55
	40	60.4	92.1	88.4	69.9	0.52
Anti-CCP2, 0.7537 (0.6953–0.8122)	20	54.5	92.1	87.3	66.9	0.47
	30	52.5	95.1	91.4	66.9	0.48
	40	51.5	98.1	96.3	66.9	0.50
Anti-carbVIMIgM and anti-MCV IgG	20	74.2	96.0	94.9	78.9	0.70
Anti-carbVIMIgM or anti-MCV IgG	20	97.0	69.3	76.0	95.9	0.66
Anti-carbVIMIgM and anti-CCP2	20/40	46.5	99.0	97.9	64.9	0.46
Anti-carbVIMIgM or Anti-CCP2	20/40	91.1	89.1	89.3	90.9	0.80

MCV mutated citrullinated vimentin, carbVIM carbamylated vimentin, Ig immunoglobulin, Se sensitivity, Sp specificity, PPV positive predictive value, NPV negative predictive value, YI Youden index