RheuMetric Quantitative 0 to 10 Physician Estimates of Inflammation, Damage, and Distress in Rheumatoid Arthritis: Validation Against Reference Measures

ObjectiveTo analyze a RheuMetric checklist, which includes four feasible physician 0 to 10 scores for DOCGL, inflammation (DOCINF), damage (DOCDAM), and distress (DOCSTR) for criterion and discriminant validity against standard reference measures. MethodsA prospective, cross-sectional assessment was performed at one routine care visit at Liverpool Hospital, Sydney, Australia. Rheumatologists recorded DOCGL, DOCINF, DOCDAM, DOCSTR, and 28 joint counts for swelling (SJC), tenderness (TJC), and limited motion/deformity (DJC). Patients completed a multidimensional health assessment questionnaire (MDHAQ), which includes routine assessment of patient index data (RAPID3), fibromyalgia assessment screening tool (FAST4), and MDHAQ depression screen (MDS2). Laboratory tests and radiographic scores were recorded. RheuMetric estimates of inflammation, damage, and distress were compared with reference and other measures using correlations and linear regressions. ResultsIn 173 patients with RA, variation in RheuMetric DOCINF was explained significantly by SJC and inversely by disease duration; variation in DOCDAM was explained significantly by DJC, radiographic scores, and physical function; and variation in DOCSTR was explained significantly by fibromyalgia and depression. ConclusionRheuMetric DOCINF, DOCDAM, and DOCSTR estimates were correlated significantly and specifically with reference measures of inflammation, damage, and distress, documenting criterion and discriminant validity.