Table 2

Multivariate regression models for BASDAI50 response and ASAS partial remission using variables with p<0.1 on univariate screening, stepwise selection and final selection of variables for both the ASSERT and the GO–RAISE datasets

	ASSERT			GO–RAISE			Combined
	All	Select	Final	All	Select	Final	All	Select	Final	Final category
Age	√, x	√, x	√, x	√, x		√, x	√, x		√, x	>/≤40 years
BASDAI score	√, x			√, x			√, x
BASFI score	√, x	√	√, x	√, x	√, x	√, x	√, x	√, x	√, x	Tertiles
BASMI score	√, x	x		√, x			√, x
Cervical rotation	√, x			√, x			√, x	x
Intermalleolar distance	√, x			√, x			√, x
Tragus to wall distance	√, x			√, x			√, x
Enthesitis score	√, x		√, x	√, x	x	√, x	√, x	√, x	√, x	0/≥1
CRP	√, x	√, x	√, x	√, x	√	√, x	√, x	√, x	√, x	Tertiles
PGA	√, x			√, x			√, x
HLA-B27	√, x		√, x	√, x	√	√, x	√, x	√, x	√, x	+/−
Treatment	√, x	√, x	√, x	√, x	√, x	√, x	√, x	√, x	√, x	Anti-TNF/placebo
R²	0.40, 0.34	0.36, 0.27	0.37, 0.27	0.27, 0.24	0.23, 0.18	0.24, 0.22	0.29, 0.26	0.27, 0.25	0.28, 0.24	0.32, 0.28
ROC–AUC (95% CI)	0.83, 0.84	0.81, 0.80	0.82, 0.80	0.77, 0.78	0.75, 0.74	0.75, 0.77	0.78, 0.79	0.77, 0.79	0.77, 0.78	0.80 (0.76–0.83), 0.77 (0.73–0.82)

R² and the area under the receiver operating characteristics curve (ROC–AUC) are presented for the different models. √ represents Bath ankylosing spondylitis disease activity index (BASDAI) 50, x represents assessment of spondyloarthritis (ASAS) partial remission. R² and ROC–AUC values are presented for BASDAI50 response, ASAS partial remission.

CRP, C-reactive protein; PGA, patient global assessment.