Recently, a joint working group of the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR) was formed to develop new classification criteria for rheumatoid arthritis (RA),1 2 and announced the 2010 ACR/EULAR classification criteria for identifying patients with early RA.3 The present study was performed in order to determine whether the newly developed 2010 ACR/EULAR criteria would include patients who were previously diagnosed with early RA according to the 1987 ACR criteria.4

We studied 170 patients with early RA patients, who had been classified as having RA according to the 1987 ACR criteria. Early RA was defined by less than 12 months of symptoms. The 2010 ACR/EULAR criteria were applied to patients at the exact time point when they were identified as fulfilling the 1987 ACR criteria. The clinical characteristics and laboratory findings …