Table 4.

Diagnostic test statistics of AAPA to discriminate eRA versus OIRD: Sensitivity, specificity and likelihood ratios.

AAPA	Sensitivity	95% CI	Specificity	95% CI	+LR	95% CI	−LR	95% CI
Ac-lysine	32.50	24.2–41.7	93.98	89.2–97.1	5.40	2.8–10.4	0.72	0.6–0.8
Ac-lysine.inv	42.00	32.2–52.3	86.52	79.8–91.7	3.12	1.9–5.0	0.67	0.6–0.8
Ac-ornithine	39.17	30.4–48.5	88.55	82.7–93.0	3.42	2.1–5.5	0.69	0.6–0.8

AAPA, anti-acetylated peptide antibodies; CI, confidence interval; eRA, early RA; +LR, positive likelihood ratio; –LR, negative likelihood ratio; OIRD, other inflammatory rheumatic diseases.