The authors conducted a study of 47 patients with a diagnosis of systemic sclerosis in order to determine the sensitivity, specificity and Youden index and consequently the diagnostic value of the generally accepted criteria and of some other common disease features. The control population consisted of 324 patients with rheumatoid arthritis and 35 patients with systemic lupus erythematosus. In addition to proximal scleroderma, the presence of which was required for inclusion in this study, other disease features score a high to moderate Youden index: sclerodactyly, Raynaud's phenomenon, appearance of perioral grooves, cinematographic evidence of esophageal hypomotility, periarticular calcifications, widening of the periodontal membrane on teeth radiographs and specific histologic changes on fingertip biopsy. Finally, a good correlation was found with most of the ARA subcommittee criteria.