OBJECTIVES: In patients with rheumatoid arthritis (RA), remission may be 
assessed by various composite measures. We assessed achievement of remission as 
defined by Boolean criteria, Simplified Disease Activity Index (SDAI), Clinical 
Disease Activity Index (CDAI), and 28-joint Disease Activity Score using 
C-reactive protein (DAS28[CRP]) and determined the components that limit 
patients in SDAI, CDAI, or DAS28(CRP) remission from achieving Boolean 
remission.
METHODS: The proportions of patients achieving Boolean, SDAI, CDAI, or 
DAS28(CRP) remission were calculated for 3 trials: PREMIER and OPTIMA in 
patients with early RA and DE019 in patients with established RA. At the first 
visit that remission was recorded during the first 52 weeks of the trial, the 
following were assessed: swollen/tender joint count at 28 and 66/68 joints, CRP, 
Patient's/Physician's Global Assessment (PGA/PhGA), SDAI, DAS28(CRP), and Health 
Assessment Questionnaire-Disability Index.
RESULTS: The majority of patients (61-66%) who achieved SDAI or CDAI remission 
also attained Boolean remission. Although DAS28(CRP) remission was most 
frequently attained, 74-77% of patients in DAS28(CRP) remission did not achieve 
Boolean remission. Compared with patients in Boolean remission, patients in SDAI 
or CDAI remission but not Boolean remission had higher PGA scores, while 
patients with DAS28(CRP) remission but not Boolean remission had higher joint 
counts, and PGA and PhGA scores.
CONCLUSIONS: Differences in PGA limit patients in SDAI/CDAI remission from 
meeting the Boolean remission criteria, suggesting that these criteria otherwise 
can be used interchangeably. In contrast, patients in DAS28(CRP) remission are 
limited by differences in multiple disease activity measures from achieving 
Boolean remission.