Construct and criterion validity of several proposed DAS28-based rheumatoid arthritis flare criteria: an OMERACT cohort validation study

Abstract

An increase in DAS28 >1.2 or >0.6 if DAS28 ≥3.2 appears most discriminating and valid by our predefined validation criteria. Considering the other criteria, sensitivity and specificity shown here might facilitate use in different settings.

Measuring Flares in Rheumatoid Arthritis. (Why) Do We Need Validated Criteria?

“…Looking at the validation of patient-reported flare criteria and the joint score and laboratory testing-based flare criteria, researchers used either patients' report on worsening, or a worsening in joint score and vice versa, thus mutually anchoring their flare criterion. For example, where Bykerk, et al (published in this journal) demonstrate a relation between patients reporting a flare and the DAS28, we in turn reported a relation between DAS28-based flare criteria and patients reporting disease worsening 15 . This well-known, back-and-forth stepping stone technique remains the solution for validation studies when no gold standard is available.…”

Evaluation of the Disease Activity Score in Twenty‐Eight Joints–Based Flare Definitions in Rheumatoid Arthritis: Data From a Three‐Year Clinical Trial

“…In this post hoc analysis, all available observations from the ACT‐RAY intent‐to‐treat (ITT) population were used to examine the occurrence of flares according to the second criterion proposed by van der Maas et al 2: increase in DAS28, between 2 visits, of >1.2 or >0.6 if the current DAS28 ≥3.2 (termed “DAS28‐2 flare”). Analyses were performed for the other proposed flare criteria (see Supplementary Table 1, available in the online version of this article at http://onlinelibrary.wiley.com/doi/10.1002/acr.22633/abstract).…”

“…This schedule is more frequent than in most published studies, which rely on assessments every 3 months. In a study phase characterized by constant treatment, in stable disease activity and minimal efficacy‐related withdrawals, the DAS28‐based flare criteria from a published validation study 2 were met quite often; however, they were mostly in relation to disease activity fluctuations isolated to a single visit, potentially due to normal variability of clinical assessments. Recent modeling work supports the existence of high random variability in DAS28 over time 5.…”

“…In this context, Outcome Measures in Rheumatology (OMERACT) has launched an initiative aimed at defining flare 1. A preliminary investigation of 6 proposed Disease Activity Score in 28 joints (DAS28)–based criteria identified an increase in DAS28 >1.2 or >0.6, if DAS28 ≥3.2, as the most discriminating and valid criterion 2.…”

“…Two specific phases of the ACT‐RAY study offer a unique opportunity to investigate relevant aspects of flares: 1) assessment of the flare rate (according to published criteria [2]) between weeks 24 and 52, during which a large patient subgroup received constant treatment 3, 4, and 2) comparison (using sensitivity and specificity) of the flare criteria implicitly used by the investigators with published criteria 2 in the second year, during which patients reaching sustained DAS28 remission discontinued tocilizumab (TCZ) and subsequently other treatments, which were re‐started after investigators diagnosed a disease flare based on their clinical judgment.…”