Table 1

Formulae of the four draft ASDAS scores

ASDAS A = 0.122×Back pain+0.061×Duration morning stiffness+0.119×Patient global+0.210×√(ESR)+0.383×Ln(CRP+1)
ASDAS B = 0.079×Back pain+0.069×Duration morning stiffness+0.113×Patient global+0.086×Peripheral pain/swelling+0.293×√(ESR)
ASDAS C = 0.121×Back pain+0.058×Duration morning stiffness+0.110×Patient global+0.073×Peripheral pain/swelling+0.579×Ln(CRP+1)
ASDAS D = 0.152×Back pain+0.069×Duration morning stiffness+0.078×Fatigue+0.224×√(ESR)+0.400×Ln(CRP+1)

  • √(ESR), square root of the erythrocyte sedimentation rate (mm/h); Ln(CRP+1), natural logarithm of C-reactive protein (mg/l) + 1.

  • Back pain, patient global, duration of morning stiffness, peripheral pain/swelling and fatigue are all assessed on a visual analogue scale (0–10 cm) or on a numerical rating scale (0–10).

  • Back pain: BASDAI Q2; duration of morning stiffness: BASDAI Q6; fatigue: BASDAI Q1; peripheral pain/swelling: BASDAI Q3.