Table 3

Test characteristics of FANA as screening test for rheumatic diseases (boys and girls combined)

FANA endpoint titre	Sensitivity	Specificity	Positive predictive value	Negative predictive value
⩾1:1280	0.18	0.98	0.80	0.74
1:640	0.24	0.96	0.69	0.75
1:320	0.32	0.88	0.53	0.76
1:160	0.42	0.75	0.41	0.76
1:80	0.53	0.60	0.36	0.76
1:40	0.63	0.47	0.33	0.75
1:20	0.67	0.36	0.30	0.73