Table 3.

Diagnostic value of individual autoantibodies for rheumatoid arthritis

	Sensitivity	Specificity	PPV	NPV	Accuracy
RF	0.66	0.87	0.80	0.76	0.78
AFA	0.33	0.93	0.79	0.63	0.66
Anti-Sa	0.22	0.98	0.88	0.61	0.64
Anti-CCP	0.41	0.91	0.78	0.66	0.69
AKA	0.26	0.84	0.56	0.58	0.58
RF+ and one or more*	0.50	0.96	0.90	0.70	0.75
RF- and one or more*	0.31	0.73	0.26	0.77	0.63

^* Includes antifilaggrin antibody (AFA), anti-Sa, cyclic citrullinated peptide (anti-CCP) and antikeratin antibody (AKA). PPV, positive predictive value; NPV, negative predictive value; RF, rheumatoid factor.