The sponsor was required to include all patients diagnosed with rheumatoid arthritis and who were treated Humira in routine medical practice during the review period by the PMDA. The safety analysis set included all patients who met all eligibility criteria and received at least one dose of Humira. The full analysis set included all patients who were treated with Humira for at least 2 weeks and had complete DAS 28 assessments at baseline and at least one other time point.

Adverse events were assessed from the time treatment began until treatment ended after 24 weeks. Details about the adverse events and serious adverse events are presented with the adverse event section of the disclosure. This outcome is measured as a percentage of patients with adverse events.

Effectiveness was assessed according to European League Against Rheumatism (EULAR) response criteria. The investigator rated patient response as good, moderate, or none from baseline to Week 4. The DAS 28 index is a measure of activity derived from the number of swollen or tender joints, laboratory tests of inflammation, and patient assessment of global health (10 cm line ranging from very good to very bad).

Effectiveness was assessed according to European League Against Rheumatism (EULAR) response criteria. The investigator rated patient response as good, moderate, or none from baseline to Week 12. The DAS 28 index is a measure of activity derived from the number of swollen or tender joints, laboratory tests of inflammation, and patient assessment of global health (10 cm line ranging from very good to very bad).

Effectiveness was assessed according to European League Against Rheumatism (EULAR) response criteria. The investigator rated patient response as good, moderate, or none from baseline to Week 24. The DAS 28 index is a measure of activity derived from the number of swollen or tender joints, laboratory tests of inflammation, and patient assessment of global health (10 cm line ranging from very good to very bad).

Physicians' rated the level of overall patient improvement as "markedly improved," "improved," "not changed," or "not assessable" by comparing clinical conditions at Week 24 or at discontinuation with baseline conditions.