Maxime Verhoeven

195 Development and validation of DAS-OST Table 4 (continued) Validation cohort Disease activity state AU-ROC Sensitivity (95%CI) Specificity (95%CI) PPV (95%CI) NPV (95%CI) accuracy External DAS-OST Remission 0.95 0.79 (0.67 - 0.91) 0.92 (0.86 - 0.97) 0.79 (0.67 - 0.91) 0.92 (0.86 - 0.97) 0.88 Boolean - - - - - - LDA 0.93 0.91 (0.84 - 0.99) 0.80 (0.72 - 0.88) 0.75 (0.65 - 0.85) 0.94 (0.88 - 0.99) 0.85 HDA 0.92 0.43 (0.26 - 0.59) 0.96 (0.93 - 1.00) 0.79 (0.61 - 0.97) 0.85(0.78 - 0.91) 0.84 DAS-OST(JC) Remission 0.95 0.84 (0.73 - 0.95) 0.91 (0.84 - 0.95) 0.77 (0.64 - 0.89) 0.93 (0.88 - 0.98) 0.89 Boolean - - - - - - LDA 0.93 0.91 (0.84 - 0.99) 0.80 (0.72 - 0.89) 0.75 (0.65 - 0.85) 0.94 (0.88 - 0.99) 0.85 HDA 0.92 0.42 (0.26 - 0.58) 0.96 (0.93 - 1.00) 0.79 (0.61 - 0.97) 0.84 (0.78 - 0.90) 0.84 DAS-OST without patient VAS Remission 0.75 0.58 (0.43 - 0.73) 0.73 (0.64 - 0.81) 0.46 (0.33 - 0.60) 0.81 (0.73 - 0.89) 0.68 Boolean - - - - - - LDA 0.74 0.93 (0.87 - 1.00) 0.47 (0.37 - 0.58) 0.53 (0.43 - 0.63) 0.91 (0.84 - 0.99) 0.65 HDA 0.83 0.00 (0.00 - 0.00) 1.00 (1.00 - 1.00) n.a. 0.77 (0.70 - 0.83) 0.77 Internal validation cohort consisted of 1120 observations from MMC cohort, not used in development cohort. External validation cohort consisted of 151 observations from the ACURA cohort. DAS-OST consisted of total OST-score, gender, ESR and VAS; DAS-OST(JC) consisted of √JC-OST, gender, ESR and VAS; DAS-OST without patient VAS consisted of total OST-score, gender and ESR. AU-ROC= area under the receiver operating characteristic curve; DAS28 Remission= DAS28≤2.6; LDA= low disease activity (DAS28≤3.2); HDA= high disease activity (DAS28>5.1); PPV= positive predictive value; NPV= negative predictive value; CI= confidence interval. 10