This study aims to evaluate, using real-world clinical practice data, the efficacy of tofacitinib in improving the clinical control of juvenile idiopathic arthritis (JIA) after 12 months of treatment.

Inclusion criteria:

Diagnosis of juvenile idiopathic arthritis (JIA) documented in the medical record by the treating rheumatologist.

Documentation in the medical record of the medical indication for tofacitinib treatment, with a diagnostic justification related to JIA.

Age under 18 years at the time of the treatment indication with tofacitinib.

Exclusion criteria:

Participants diagnosed with any of the following conditions:

Reactive arthritis

Arthritis associated with inflammatory bowel disease

Arthritis associated with another autoimmune disease

Patients with JIA

IPD (without personal identification data) could be shared by requirement from other researchers after the end of the study, and only for research purposes and previous approval of promotor center of the study (CSAPG). Anyway, Spanish and European Union legal policy about data protection will strictly be followed (IPD will not be transferred outside European Union).

After publication of main results of the study.

IPD will be shared only for scientific research purposes and following the Spanish and European Union normative law about data protection. The requirements will be directed to the IP of the study. The IP will evaluate the request to verify and evaluate the data that is requested and the purposes for which it is requested. Next, the IP will transfer the request to the promotor center the study for the final decision.