We evaluated disease status in relation to age, sex and disease duration using some short term indices of disease activity, laboratory tests, and radiological features in 315 patients with rheumatoid arthritis of duration varying from 3 to 36 months (mean 12 months). No differences were observed among various age groups in disease duration, female/male ratio, incidence of radiologic lesions and other indices of disease process. Some clinical markers of the disease process such as involvement of the flexor tendons of the hands and Ritchie's index (score greater than 9) were significantly more frequent in the women (p less than 0.0013 and p less than 0.04, respectively). In the patients with disease of recent onset women were slightly more numerous (56%) than men; however, in those with disease duration of 36 months there were significantly more women (72%) (p less than 0.039), suggesting a greater tendency to chronic disease in this sex. Radiological lesions of the small joints of the hands, feet, and/or wrists were found in 37% of the cases with disease duration of up to 4 months and in 91% at 36 months (p less than 0.0001). The lesions were associated significantly more frequently with Ritchie index (p less than 0.02) and with laboratory indices of inflammatory activity (erythrocyte sedimentation rate greater than or equal to 25 mm/h) (p less than 0.001) and immune response (latex test greater than or equal to 80) (p less than 0.0001). Logistic regression analysis showed that the duration of illness is the most important factor correlating with radiologic lesions.