Table 3

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

Treatment target at 6 months: SDAI remission	Specificity (when 80% sensitivity)	3-month SDAI improvement	PPV	NPV	LR+	LR−
All patients	0.68	56.9%	0.23	0.97	2.41	0.29
Baseline SDAI MDA	0.70	53.4%	0.32	0.95	2.68	0.28
Baseline SDAI HDA	0.79	72.0%	0.22	0.98	3.89	0.24
Disease duration ≤12 months	0.67	62.3%	0.25	0.96	2.46	0.29
Disease duration >12 months	0.72	56.9%	0.24	0.97	2.88	0.27
DMARD-naïve starting MTX	0.65	62.3%	0.25	0.96	2.29	0.30
bDMARD-naïve starting TNFi	0.63	58.5%	0.30	0.94	2.19	0.32
Treatment target at 6 months: SDAI low disease activity
All patients	0.51	33.8%	0.59	0.74	1.65	0.39
Baseline SDAI MDA	0.59	24.2%	0.74	0.67	1.94	0.34
Baseline SDAI HDA	0.65	51.2%	0.54	0.86	2.27	0.31
Disease duration ≤12 months	0.50	35.8%	0.64	0.69	1.60	0.40
Disease duration >12 months	0.52	32.3%	0.55	0.78	1.67	0.38
DMARD-naïve starting MTX	0.49	36.6%	0.66	0.66	1.55	0.42
bDMARD-naïve starting TNFi	0.59	44.3%	0.67	0.74	1.97	0.33

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.