| TNF Yes (n = 358) Mean (SD) | TNF No (n = 350) Mean (SD) | Standardised mean difference | |
| ASDAS A | 3.87 (1.01) | 2.71 (0.96) | 1.18 |
| ASDAS B | 3.52 (0.97) | 2.43 (0.95) | 1.14 |
| ASDAS C | 3.49 (0.99) | 2.44 (0.98) | 1.07 |
| ASDAS D | 3.94 (1.02) | 2.81 (0.96) | 1.14 |
| BASDAI | 5.45 (2.05) | 3.75 (2.17) | 0.81 |
| Ln (CRP+1) | 2.72 (1.07) | 1.99 (0.96) | 0.71 |
| CRP (mg/l)*, median (range) | 13 (0.50–120) | 3 (0.50–80) | |
| √(ESR) | 5.45 (2.09) | 3.87 (1.72) | 0.82 |
| ESR* (median, range) | 25.5 (1–88) | 12 (1–66) | |
| Ln (swollen joint count+1) | 0.55 (0.81) | 0.30 (0.60) | 0.35 |
| Swollen joint count*, median (range) | 0 (0–12) | 0 (0–10) | |
| √(Tender enthesis count) | 1.78 (1.38) | 1.14 (1.26) | 0.48 |
| Tender enthesis count*, median (range) | 2.5 (0–24) | 0 (0–10) | |
| Back pain at night | 5.10 (2.80) | 3.33 (2.60) | 0.65 |
| Total spinal pain (pain spine) | 5.32 (2.57) | 3.69 (2.47) | 0.65 |
| Patient global assessment | 6.05 (2.43) | 4.02 (2.55) | 0.81 |
| BASDAI question 1 (fatigue) | 5.88 (2.60) | 3.75 (2.17) | 0.89 |
| BASDAI question 2 (back pain) | 6.52 (2.51) | 4.50 (2.66) | 0.79 |
| BASDAI question 3 (peripheral pain/swelling) | 4.22 (3.14) | 4.67 (2.69) | −0.16 |
| BASDAI question 6 (duration of morning stiffness) | 5.26 (3.07) | 4.05 (2.86) | 0.41 |
| BASFI | 5.29 (2.50) | 3.35 (2.54) | 0.77 |
*For information purposes only, actual values are presented.
ASDAS, Ankylosing Spondylitis Disease Activity Score; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; ISSAS, International Study on Starting TNF blocking agents in Ankylosing Spondylitis; TNF, tumour necrosis factor.