Table 3

Diagnostic characteristics of extra-articular manifestations (EAMs) for histologically proven rheumatoid vasculitis in 81 patients suspected of rheumatoid vasculitis

	Sensitivity	Specificity	Accuracy	PPV	NPV
Accuracy, percentage patients correctly classified as either HRV or RA+EAM; PPV, positive predictive value; NPV, negative predictive value.
*Weighted EAM score; for explanation see “Patients and methods”.
EAM
Peripheral neuropathy	45	88	72	70	72
Purpura/petechiae	45	94	75	82	73
Peripheral neuropathy or purpura/petechiae	81	84	83	76	88
Number of EAM
⩾1	100	0	38	38	–
⩾2	77	46	58	47	77
⩾3	42	84	68	62	70
⩾4	23	100	70	100	68
Weighted EAM score*
⩾3	100	50	56	55	100
⩾5	58	80	72	64	76
⩾6	45	90	73	74	73
⩾9	19	100	69	100	67