Article
Author: Sinnathurai, Premarani ; Holt, Robert J ; Leung, Ying Ying ; Halls, Serena ; Lyddiatt, Anne ; Hill, Catherine L ; Kirwan, John R ; Leong, Amye L ; Alten, Rieke ; Campbell, Ina ; Hewlett, Sarah ; Mackie, Sarah L ; Bingham, Clifton O ; Hughes, Rod ; Bartlett, Susan J ; March, Lyn ; Orbai, Ana-Maria ; Neill, Lorna
OBJECTIVE:The objectives of the Outcome Measures in Rheumatology (OMERACT) Stiffness special interest group (SIG) are to characterize stiffness as an outcome in rheumatic disease and to identify and validate a stiffness patient-reported outcome (PRO) in rheumatology.
METHODS:At OMERACT 2016, international groups presented and discussed results of several concurrent research projects on stiffness: a literature review of rheumatoid arthritis (RA) stiffness PRO measures, a qualitative investigation into the RA and polymyalgia rheumatica patient perspective of stiffness, data-driven stiffness conceptual model development, development and testing of an RA stiffness PRO measure, and a quantitative work testing stiffness items in patients with RA and psoriatic arthritis.
RESULTS:The literature review identified 52 individual stiffness PRO measures assessing morning or early morning stiffness severity/intensity or duration. Items were heterogeneous, had little or inconsistent psychometric property evidence, and did not appear to have been developed according to the PRO development guidelines. A poor match between current stiffness PRO and the conceptual model identifying the RA patient experience of stiffness was identified, highlighting a major flaw in PRO selection according to the OMERACT filter 2.0.
CONCLUSION:Discussions within the Stiffness SIG highlighted the importance of further research on stiffness and defined a research agenda.