Deriving an operational definition of low disease activity state in rheumatoid arthritis.
This article summarizes the process proposed to come to a definition of low disease activity in rheumatoid arthritis (RA). The purpose of this definition is to aid the interpretation of trial and longitudinal study results. A conceptual proposal is "a disease activity state that is deemed a useful treatment target by both physicians and patients." An operant definition can be derived by judgmental (opinion-based) or statistical (data-based) approaches, but the first seems more appropriate. Once a few candidate definitions have been selected, their usefulness and prognostic validity can be tested in longitudinal datasets.
VU University Medical Centre, Amsterdam, The Netherlands. m.boers@azvu.nl
Maarten
M
Boers
Jennifer J
JJ
Anderson
David T
DT
Felson
D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D006801:Humans; D010043:Outcome and Process Assessment, Health Care; D012720:Severity of Illness Index