Remission of rheumatoid arthritis: should we care about definitions?

A state of remission can be achieved in more and more rheumatoid arthritis (RA) patients. The combination of several RA disease activity measures seems to be important to provide an overall view of disease activity. Remission can be defined by two different approaches: one using a categorical model, requiring criteria for multiple variables to be fulfilled, each with its own threshold value (remission "criteria"); the other using a dimensional model, providing single measures of activity, which allow definition of remission by a single cut point (remission cut points for composite indices). The face validity of remission as defined by composite indices surpasses the one for the "criteria". Likewise, the ones that are not weighted seem to surpass the weighted ones, as can be seen by the significant proportion of patients that continues to have considerable swollen joint counts despite being in Disease Activity Score (DAS)-28 remission. All composite indices seem to perform similarly well as tests for remission using expert judgments as the gold standard.