047. Rheumatoid Factor Testing in Spanish Primary Care Costs€ 1432 Per True Positive Case of Rheumatoid Arthritis; A Study Using Electronic Data from the Information System for …

Background: Early treatment of patients with RA is important to prevent long-term joint damage and disability. Many general practitioners (GPs) undertake RF testing to distinguish early RA from a larger number of patients with non-inflammatory joint pain. The aim of the study was to examine the impact of negative RF tests on time to RA diagnosis between 2000 and 2010 using the UK Clinical Practice Research Datalink (CPRD).Methods: Incident cases of RA, with at least 2 years of data in their record before diagnosis, were identified from the CPRD using a previously validated algorithm. We identified all RF tests in the 2 years before diagnosis and classified them as positive or negative based on the recorded upper value for the normal range (UNR). Where...