TY - JOUR T1 - How to Define Baseline Erosiveness to Predict Radiologic Progression in Rheumatoid Arthritis JF - The Journal of Rheumatology JO - J Rheumatol SP - 1624 LP - 1625 DO - 10.3899/jrheum.130319 VL - 40 IS - 9 AU - LING YIN HO AU - DIEDERIK P.C. de ROOY AU - ANNETTE H.M. van der HELM-van MIL Y1 - 2013/09/01 UR - http://www.jrheum.org/content/40/9/1624.abstract N2 - To the Editor:Baseline erosiveness is a potent predictive factor used in daily practice for predicting a severe destructive disease course in rheumatoid arthritis (RA). However, there is no uniform definition of erosive disease at disease onset. The definitions used in some studies were highly variable: radiological evidence of erosions1,2, a cortical break ≥ 2 mm3, or presence of ≥ 2 or ≥ 3 erosions4,5. The lack of a generally accepted definition makes studies on this subject difficult to compare. Moreover, it prevents the use of radiological information at disease presentation in a consistent manner in clinical practice.The radiologic criterion to classify RA, according to the 2010 criteria, was presented and defined as the presence of at least 3 erosive joints6,7. An erosive joint was defined as a metacarpophalangeal (MCP), proximal inter-phalangeal (PIP), metatarsophalangeal (MTP), or wrist joint with a broken cortex on a radiograph. This measure is easily applicable in clinical practice. This prompted us to (1) … Address correspondence to Dr. D.P.C. de Rooy, Department of Rheumatology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands. E-mail: d.p.c.de_rooy{at}lumc.nl ER -