Table 4

SDAI improvement cut-points at 3 months when predicting achievement of the treatment targets at 6 months with 80% specificity

Treatment target at 6 months:
SDAI remission
Sensitivity (when 80% specificity)3-month SDAI improvementPPVNPVLR+LR−
All patients0.6469.2%0.280.953.190.45
Baseline SDAI MDA0.6564.2%0.360.933.300.44
Baseline SDAI HDA0.7972.7%0.220.983.960.26
Disease duration ≤12 months0.6673.0%0.320.943.360.42
Disease duration >12 months0.6865.8%0.270.963.400.40
DMARD-naïve starting MTX0.6573.0%0.320.943.300.44
bDMARD-naïve starting TNFi0.5873.0%0.370.912.980.52
Treatment target at 6 months:
SDAI low disease activity
All patients0.5360.2%0.700.662.650.59
Baseline SDAI MDA0.6246.5%0.820.593.110.48
Baseline SDAI HDA0.6365.2%0.620.813.210.46
Disease duration ≤12 months0.4866.0%0.730.582.510.64
Disease duration >12 months0.5455.6%0.670.702.760.57
DMARD-naïve starting MTX0.4666.6%0.740.552.310.67
bDMARD-naïve starting TNFi0.5464.7%0.750.622.840.57
  • b, biological; DMARD, disease-modifying antirheumatic drug; HDA, high disease activity; LR+, positive likelihood ratio; LR−, negative likelihood ratio; MDA, moderate disease activity; MTX, methotrexate; NPV, negative predictive value; PPV, positive predictive value; SDAI, Simplified Disease Activity Index; TNFi, tumour necrosis factor inhibitor.