Radiographic evaluation of the course of articular disease.

Radiological analysis is the single most attractive objective method for assessing the long-term anatomical effects of rheumatoid arthritis. Measurement of x-ray changes has given us our most important clues on the effectiveness of disease-modifying drugs. Although no single system has been adopted by all investigators to quantify radiological changes, most investigators have used joint counts or scores which have many properties of an interval scale to measure erosions and, at times, joint space narrowing. More extensive use of radiological analysis in therapeutic trials, if based on a thorough understanding of the natural history of radiological progression in rheumatoid arthritis, should provide a more accurate appraisal of our ability to modify the course of the disease.