Clinically Important Changes in Rheumatoid Arthritis

Proper interpretation of the results of clinical trials requires an assessment of not only the statistical significance of treatment differences but also the clinical importance of such differences. Efforts to define criteria for important improvement in rheumatoid arthritis (RA) activity have thus far not considered the patient's perspective. The aim of this project is to determine if criteria for important improvement in arthritis activity measures can be defined. This will be done by assessing the agreement among patients of judgments of important changes in arthritis activity. We will also determine if preference measures, which are a group of measures of the desirability of a particular state of health, can be used to assess when patients experience an important change in their arthritis. This prospective longitudinal observational study will measure changes in 12 arthritis activity measures, changes in preference measures, and judgments of the importance of changes in arthritis activity over one to four months in 300 patients with active RA. Consensus among patients regarding the degree of change considered important would allow group criteria for important improvement to be defined that were based on patients' evaluations.