Structural construct validity of SDAI response cutpoints in the active treatment arms of ASPIRE and ATTRACT (response status at 6 month, radiographic progression over year 1; mean±SD)
| ASPIRE | ATTRACT | ||
|---|---|---|---|
| SDAI response category | MTX | MTX+IFX | IFX |
| No response | 5.6±12.6 (n=59) | 1.8±6.4 (n=107) | 2.9±8.5 (n=50) |
| SDAI50 | 3.9±9.8 (n=42) | 0.6±4.5 (n=79) | 0.3±3.5 (n=61) |
| SDAI70 | 2.2±6.6 (n=35) | 0.3±4.3 (n=98) | 0.1±5.5 (n=49) |
| SDAI85 | −0.3±5.9 (n=44) | −0.4±5.2 (n=179) | 0.3±4.5 (n=43) |
| p=0.09 | p=0.01 | p=0.67 | |
IFX, infliximab; MTX, methotrexate; SDAI, Simplified Disease Activity Indices.