Table 2 Univariate correlations between mSASSS and BASFI or DFI for the entire population and stratified for different levels of the BASDAI
Correlation for mSASSS with:
BASFIDFI
All patients (n = 217)0.45*0.38
Patients with BASDAI 0–2 (n = 68)0.680.60
Patients with BASDAI >2–4 (n = 60)0.580.47
Patients with BASDAI >4–6 (n = 60)0.430.31
Patients with BASDAI >6–8 (n = 22)0.400.15
Patients with BASDAI >8–10 (n = 7)−0.20−0.20

  • *Values are Spearman correlation coefficients.

  • BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; DFI, Dougados Functional Index; mSASSS, modified Stoke Ankylosing Spondylitis Spine Score.