PT - JOURNAL ARTICLE AU - Sogol S. Amjadi AU - Paul M. Maranian AU - Harold E. Paulus AU - Robert M. Kaplan AU - Veena K. Ranganath AU - Daniel E. Furst AU - Puja P. Khanna AU - Dinesh Khanna TI - Validating and Assessing the Sensitivity of the Health Assessment Questionnaire-Disability Index-derived Short Form-6D in Patients with Early Aggressive Rheumatoid Arthritis AID - 10.3899/jrheum.080959 DP - 2009 Apr 01 TA - The Journal of Rheumatology PG - jrheum.080959 4099 - http://www.jrheum.org/content/early/2009/04/14/jrheum.080959.short 4100 - http://www.jrheum.org/content/early/2009/04/14/jrheum.080959.full AB - Objective New methodologies allow the scores for the Health Assessment Questionnaire-Disability Index (HAQ-DI) to be translated into preferences/utility scores. We evaluated the construct validity of the HAQ-DI-derived Short Form-6D (SF-6D) score and assessed its responsiveness to change over 6- and 12-month followup periods in patients with early aggressive rheumatoid arthritis (RA). Methods Patients (n = 277) participating in an RA observational study completed self-reported measures of symptoms and the HAQ-DI at baseline and at 6 and 12 months. Total Sharp scores, C-reactive protein, and erythrocyte sedimentation rate were assessed along with clinical data. Construct validity was assessed by examining the association between SF-6D score and patientreported and clinical measures using Spearman correlation coefficients. The responsiveness of SF-6D to change was assessed using patient and physician assessments of the disease as clinical anchors. The magnitude of responsiveness was calculated using SF-6D effect size (ES). Results Mean SF-6D scores were 0.690, 0.720, and 0.723 at baseline and 6 and 12-month followup, respectively. Baseline patient-reported measures had moderate to high correlations with baseline SF-6D (r = 0.43 to 0.52); whereas clinical measures had negligible to low correlations with SF-6D (r = 0.001 to 0.32). ES was moderate for the groups that were deemed to have improved (ES 0.63–0.75) but negligible to small for those that did not (ES 0.13–0.46). Conclusion Our data support the validity and responsiveness of the HAQ-DI derived SF-6D score in an early RA cohort. These results support the use of the HAQ-DI derived SF-6D in RA cohorts and clinical trials lacking preference-based measures.