American College of Rheumatology criteria at inception, and accrual over 5 years in the SLICC inception cohort.

Objective: To determine the frequency of each American College of Rheumatology (ACR) criterion met at time of enrollment, and the increase in each of the criteria over 5 years.

Methods: In 2000 the Systemic Lupus International Collaborating Clinics (SLICC) recruited an international inception cohort of patients with systemic lupus erythematosus (SLE; ≥ 4 ACR criteria) who were followed at yearly intervals according to a standard protocol. Descriptive statistics were used to assess the total and cumulative number of ACR criteria met at each visit.