Validation of prediction models of severe disease course and non-achievement of remission in juvenile idiopathic arthritis part 2: results of the Nordic model in the Canadian cohort

Table 3 Changes to model coefficients for the Nordic model to predict non-achievement of remission made during the fine-tuning process

Variable	Original Nordic	Fine-tuned Canada to predict non-achievement of remission		Fine-tuned Canada to predict severe disease course
Variable	Original Nordic	With lab tests	No lab tests	With lab tests	No lab tests
Constant (intercept)	- 1.58 (- 0.70, -2.46)*	0.24	0.17	− 2.9	− 2.8
Active joint count**	0.04 (- 0.06, 0.14)	0.16	0.15	0.22	0.21
ESR in mm/h	0.03 (- 0.01, 0.07)	- 0.01	–	− 0.01	–
CRP > 10 mg/L	- 0.07 (- 1.45, 1.31)	0.12	–	0.08	–
Morning stiffness > 15 min	1.16 (0.26, 2.06)	0.42	0.38	0.23	− 0.03
Physician global assessment	0.16 (- 0.76, 1.08)	0.15	0.14	− 0.05	− 0.06
ANA positive	1.25 (0.25, 2.25)	0.03	–	− 0.56	–
HLA-B27 positive	1.37 (0.29, 2.45)	1.07	–	0.85	–
Ankle joint arthritis	1.10 (0.12, 2.08)	0.52	0.53	− 0.70	− 0.70
C-index (95% CI)	0.68 (0.62, 0.74)	0.74 (0.67, 0.80)	0.74 (0.67, 0.81)	0.79 (0.68, 0.91)	0.79 (0.69, 0.89)

*Numbers in parentheses are the 95% confidence interval
**The Nordic cohort used the cumulative active joint count within 6 months of disease onset, while the ReACCh-Out cohort used the active joint count at baseline

ISSN: 1478-6362