Disease Activity in Psoriatic Arthritis: Comparison of the Discriminative Capacity and Construct Validity of Six Composite Indices in a Real World

Table 3

Criterion values and coordinates of the ROC curve for MDA and remission criteria according to the different composite indices.

Composite activity indices	Optimal cut-off value	Sensitivity	95% CI	Specificity	95% CI	+LR	95% CI	−LR	95% CI
Minimal disease activity
DAS28-CRP	≤3.6	76.09	66.1–84.4	88.75	79.7–94.7	6.76	3.6–12.6	0.27	0.2–0.4
DAS28-ESR	≤3.6	72.83	62.6–81.6	88.75	79.7–94.7	6.47	3.5–12.1	0.31	0.2–0.4
SDAI	≤11	79.35	69.6–87.1	88.75	79.7–94.7	7.05	3.8–13.2	0.23	0.2-0.3
CPDAI	≤5	68.48	58.0–77.8	83.54	73.5–90.9	4.16	2.5–7.0	0.38	0.3–0.5
DAPSA	≤15	77.17	67.2–85.3	88.75	79.7–94.7	6.86	3.7–12.8	0.26	0.2–0.4
PASDAS	≤3.6	76.09	66.1–84.4	86.25	76.7–92.9	5.53	3.2–9.7	0.28	0.2–0.4
Remission
DAS28-CRP	<2.4	72.00	63.3–79.7	89.36	76.9–96.5	6.77	2.9–15.6	0.31	0.2–0.4
DAS28-ESR	<2.4	71.20	62.4–78.9	88.86	76.1–96.1	6.69	2.8–15	0.32	0.2–0.4
SDAI	<3.3	73.60	65.0–81.1	90.16	77.1–96.9	6.92	3.0–15.9	0.30	0.2–0.4
CPDAI	<2	68.55	59.6–76.6	85.11	71.7–93.8	4.60	2.3–9.2	0.37	0.3–0.5
DAPSA	<4	72.80	64.1–80.4	89.36	76.9–96.5	6.84	3.0–15.8	0.30	0.2–0.4
PASDAS	<2.4	75.20	66.7–82.5	85.11	71.7–93.8	5.05	2.5–10.1	0.29	0.2–0.4

LR: likelihood ratio; 95% CI: 95% confidence intervals; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein; SF36 PCS: physical component summary score of the Medical Outcome Survey Short Form-36; SF36MCS: mental component summary score of the Medical Outcome Survey Short Form-36; DLQI: Dermatology Life Quality Index; HAQ: Health Assessment Questionnaire; DAS28: 28-Disease Activity Score; SDAI: Simplified Disease Activity Index; CPDAI: Composite Psoriatic Disease Activity Index; DAPSA: disease activity in psoriatic arthritis; PASDAS: Psoriatic Arthritis Disease Activity Score.