THU0706 Low disease activity after a short course of drug therapy and rehabilitation is associated to a greater improvement in functional capacity in rheumatoid arthritis

Abstract

specificity of MRI-detected inflammation increased from 22% to 56% in CSApatients, and from 10% to 36% in UA-patients. The sensitivity was not affected; it was 88% and 85% in CSA-patients and 93% and 93% in UA-patients. The accuracy also increased, from 32% to 60% in CSA-patients and 22% to 44% in UA-patients. Conclusions: The use of a reference population resulted in a substantial reduction of false-positive results, without affecting the sensitivity. This is of high importance because of the potential risks of false-positive MRI-results, for example in the setting of UA as a positive MRI-result may influence the decision to initiate disease modifying medication. Although a reference population is generally used in medicine for other tests to derive a definition of a positive test result, this is the first study demonstrating the value of a reference population to define a "positive MRI".