Rheumatoid arthritis: assessing disease activity and outcome.

The range of treatments for rheumatoid arthritis (RA) has increased significantly in recent years, with a parallel improvement in patient outcome. The development and assessment of new therapies and therapeutic strategies relies on the availability of valid and reliable outcome measures to assess the diverse impact of RA on the patient's life. This paper reviews the outcome measures in current use which assess disease activity, joint damage, physical function and health-related quality of life. Some measures have been combined into composite indices which are useful for summarising the patient's current condition and as primary outcome measures for clinical trials. There is still a need for better and more relevant tools especially for imaging multiple joints and for assessing fatigue.