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. 2021 Jul 30;9(7):e26823. doi: 10.2196/26823

Table 4.

Percentage of models in which a variable was statistically significant; percentage of models in which a variable had a positive coefficient sign; the percentage of models in which a variable had a negative coefficient sign for the covariates present in the joint models fitted for data sets A, B, C, and D; and the average of those percentages across all data sets.

Variable Data set (%) Average (%)
A B C D
ssa posb negc ss pos neg ss pos neg ss pos neg ss pos neg
Male (ref: female) N/Ad N/A N/A N/A N/A N/A N/A N/A N/A 0 46 54 0 46 54
Year of disease onset N/A N/A N/A N/A N/A N/A 92 75 25 N/A N/A N/A 92 75 25
Year biologic therapy initiation 82 36 64 83 67 25 N/A N/A N/A N/A N/A N/A 83 52 45
Age at start of the first biologic therapy 82 0 100 N/A N/A N/A N/A N/A N/A N/A N/A N/A 82 0 100
Disease years until start of the first biologic therapy N/A N/A N/A N/A N/A N/A N/A N/A N/A 15 0 100 15 0 100
HLA-B27e N/A N/A N/A N/A N/A N/A 83 0 100 N/A N/A N/A 83 0 100
Years of education 82 100 0 100 100 0 N/A N/A N/A 85 100 0 91 100 0
Baseline CRPf N/A N/A N/A N/A N/A N/A N/A N/A N/A 44 100 0 44 100 0
Baseline BASFIg 50 100 0 75 100 0 25 63 37 50 100 0 50 91 9
CRP 67 100 0 100 100 0 100 100 0 100 100 0 92 100 0
ESRh 50 100 0 100 100 0 100 100 0 100 100 0 88 100 0
BASDAIi 100 100 0 100 100 0 100 100 0 100 100 0 100 100 0
BASFI 33 33 66 50 50 50 50 50 50 60 60 40 48 48 52
ASDASj 100 100 0 100 100 0 100 100 0 100 100 0 100 100 0

ass: percentage of models in which variable is statistically significant.

bpos: percentage of models in which variable has positive coefficient.

cneg: percentage of models in which variable has negative coefficient.

dN/A: not applicable.

eHLA-B27: human leukocyte antigen B27.

fCRP: C-reactive protein.

gBASFI: Bath Ankylosing Spondylitis Functional Index.

hESR: erythrocyte sedimentation rate.

iBASDAI: Bath Ankylosing Spondylitis Disease Activity Index.

jASDAS: Ankylosing Spondylitis Disease Activity Score.