Baseline characteristics of patients in the safety cohort
| Characteristic | Safety cohort N=191 |
| Age at etanercept start, median (Q1, Q3), years | 10.0 (6.0, 14.0) |
| Age at start of follow-up, median (Q1, Q3), years | 12.0 (8.0, 15.0) |
| Sex, n (%) | |
| Female | 126 (66.0) |
| Male | 65 (34.0) |
| Race, white, n (%) | 154 (80.6) |
| Disease duration at start of follow-up, median (Q1, Q3), years | 2.4 (0.5, 5.3) |
| Concomitant use of non-biologic therapy at start of follow-up, n (%) | 113 (59.2) |
| Methotrexate | 107 (56.0) |
| Leflunomide | 4 (2.1) |
| Sulfasalazine | 5 (2.6) |
| Any etanercept use before CARRA Registry enrolment, n (%) | 119 (62.3) |
| Number of patients with biologic use prior to etanercept, n (%) | 17 (8.9) |
| Adalimumab, n (%) | 16 (8.4) |
| Tocilizumab, n (%) | 1 (0.5) |
| Ongoing etanercept use at time of CARRA Registry enrolment, n (%) | 107 (56.0) |
| Among patients with ongoing etanercept use at time of CARRA Registry enrolment | |
| Cumulative duration of etanercept use before CARRA Registry enrolment | |
| Mean (SD), months (number of patients with available data) | 29.5 (32.4) (107) |
| Median (Q1, Q3), months (number of patients with available data) | 14.9 (5.8, 38.8) (107) |
| Elapsed time since etanercept initiation | |
| Mean (SD), months (number of patients with available data) | 31.0 (33.7) (107) |
| Median (Q1, Q3), months (number of patients with available data) | 15.9 (5.8, 42.9) (107) |
N=number of patients who met the criteria for the safety cohort, that is, had a rheumatologist-diagnosed JIA category of PsA, did not have ongoing concurrent biologic use at etanercept initiation and had observed time on etanercept during CARRA Registry enrolment; n=number of patients with the characteristic.
CARRA, Childhood Arthritis and Rheumatology Research Alliance; JIA, juvenile idiopathic arthritis; PsA, psoriatic arthritis; Q1, quartile 1; Q3, quartile 3.