Comprehensive data about new treatments for rheumatoid arthritis (RA), including their potential for disease remission, efficacy, and safety, are derived from clinical research. Often these studies can significantly influence management strategies for patients with RA. Virtually all recent studies on RA report disease characteristics relevant to outcome. Factors such as the presence of rheumatoid factor, the number of tender and swollen joints, measurements of acute phase reactants, the presence of radiographic erosions, and prior treatments with disease modifying antirheumatic drugs define the severity of disease, and also, the potential for responses to treatments. The age and sex of the study population are also …