Predictive validity of candidate remission definitions for good outcome in adiographic damage*
| Prevalence of good outcome in patients | ||||
|---|---|---|---|---|
| Candidate remission definition | In remission | Not in remission | Positive likelihood ratio (95% CI) | p† |
| TJC28, SJC28, CRP ≤1 | 69 (34/49) | 50 (154/306) | 2.0 (1.1 to 3.6) | 0.01 |
| TJC28, SJC28, CRP, PhGA ≤1 | 76 (26/34) | 51 (162/320) | 2.9 (1.3 to 6.2) | 0.004 |
| TJC28, SJC28, CRP, PtGA ≤1 | 77 (23/30) | 51 (165/325) | 2.9 (1.3 to 6.6) | 0.006 |
| TJC28, SJC28, CRP, pain ≤1 | 74 (23/31) | 51 (165/324) | 2.6 (1.2 to 5.6) | 0.01 |
| TJC28, SJC28, CRP, PhGA, PtGA ≤1 | 77 (20/26) | 51 (168/328) | 2.9 (1.2 to 7.2) | 0.01 |
| TJC28, SJC28, CRP, PhGA, pain ≤1 | 77 (20/26) | 51 (168/328) | 2.9 (1.2 to 7.2) | 0.01 |
| TJC28, SJC28, CRP, PtGA, pain ≤1 | 76 (22/29) | 51 (166/326) | 2.8 (1.2 to 6.4) | 0.001 |
| TJC28, SJC28, CRP, PhGA, PtGA, pain ≤1 | 76 (19/25) | 51 (169/329) | 2.8 (1.1 to 6.8) | 0.02 |
| DAS28 <2.6 | 60 (21/35) | 59 (93/157) | 1.0 (0.6 to 1.9) | 0.93 |
| DAS28 <2.0 | 70 (7/10) | 59 (107/182) | 1.6 (0.4 to 6.0) | 0.48 |
| SDAI ≤3.3‡ | 77 (27/35) | 50 (161/319) | 3.0 (1.4 to 6.4) | 0.003 |
| Definitions without CRP (for clinical practice) | ||||
| TJC28, SJC28, PhGA, PtGA ≤1 | 75 (24/32) | 51 (167/326) | 2.6 (1.2 to 5.7) | 0.01 |
| TJC28, SJC28, PtGA ≤1 | 75 (27/36) | 51 (164/323) | 2.6 (1.3 to 5.4) | 0.007 |
| CDAI ≤2.8§ | 75 (27/36) | 51 (164/322) | 2.6 (1.3 to 5.4) | 0.006 |
↵* Values in the first two columns are percentages, with absolute proportions shown in parentheses. Presence or absence of remission, defined according to the given candidate definition, was measured at 6 months after baseline, using combined data from methotrexate-alone treatment groups in three trials37 40 41 (limited to patients with complete data over 2 years). Good radiographic outcome was defined as a change of ≤0 in Sharp/van der Heijde scores between 12 and 24 months after baseline. CRP is in mg/dl.
↵† From χ2 analysis using logistic regression, in which the independent variable was remission (based on the given candidate definition) and the dependent variable was radiographic stability.
↵‡ SDAI is the simple sum of the TJC (using 28 joints), SJC (using 28 joints), patient global assessment (0–10 scale), physician global assessment (0–10 scale), and CRP level (mg/dl).
↵§ CDAI is the same as the SDAI, except CRP is not included.
CDAI, Clinical Disease Activity Index; CRP, C reactive protein; DAS28, 28-joint Disease Activity Score (see table 1 for other definitions); PhGA, physician/observer global assessment; PtGA, patient global assessment; SDAI, Simplified Disease Activity Index; SJC, swollen joint count; TJC, tender joint count.