TNF and rheumatoid arthritis: Patients were included in this study if they initiated therapy with conventional synthetic disease-modifying antirheumatic drug (csDMARD) monotherapy, TNF inhibitor (TNFi) monotherapy, other (non-TNFi) biologic monotherapy, or combination therapy (index therapy); initiated therapy between January 1, 2004, and December 31, 2015 (index date), after enrollment in the Corrona RA registry; had at least 6 months of follow-up time after the index date; and had at least one follow-up visit.