PT  - JOURNAL ARTICLE
AU  - Maarten Boers
AU  - Jennifer J Anderson
AU  - David T Felson
TI  - Deriving an operational definition of low disease activity state in rheumatoid arthritis.
DP  - 2003 May 01
TA  - The Journal of Rheumatology
PG  - 1112--1114
VI  - 30
IP  - 5
4099  - http://www.jrheum.org/content/30/5/1112.short
4100  - http://www.jrheum.org/content/30/5/1112.full
SO  - J Rheumatol2003 May 01; 30
AB  - 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.