1528 The Journal of Rheumatology 2008; 35:8 Personal non-commercial use only. The Journal of Rheumatology Copyright © 2008. All rights reserved. Health-Related Quality of Life: Validity, Reliability, and Responsiveness of SF-36, EQ-15D, EQ-5D, RAQoL, and HAQ in Patients with Rheumatoid Arthritis LOUISE LINDE, JAN SØRENSEN, MIKKEL ØSTERGAARD, KIM HØRSLEV-PETERSEN, and MERETE LUND HETLAND ABSTRACT. Objective. To compare validity, reliability, and responsiveness of generic and disease specific health- related quality of life (HRQOL) instruments in rheumatoid arthritis (RA). Methods. Two samples of patients completed the Medical Outcomes Study Short Form-36 Health Survey (SF-36), EuroQol (EQ)-5D, 15D, Rheumatoid Arthritis Quality of Life Scale (RAQoL), HealthAssessment Questionnaire (HAQ), and visual analog scales (VAS) for pain, fatigue, and glob- al RA.Validity (convergent, discriminant, and known-groups) was evaluated in a cross-section of 200 patients. Reliability was evaluated by agreement (intraclass correlation coefficient; baseline to 2 weeks) and internal consistency (Cronbach’s alpha); and responsiveness by the standardized response mean stratified on improvement, status quo, or deterioration in health status after 6 months in 150 patients followed longitudinally. Followup questionnaires (at 2 weeks and 6 months) includ- ed questions about changes in health status since baseline. Results. The cross-sectional sample included 77% women, median age 57 years (range 19–87), dis- ease duration 6 years (0–58), with Disease Activity Score 28-joint count (DAS28) of 3.10 (1.21–6.47). The longitudinal sample included 80% women, median age 60 years (22–82).Validity: all instruments discriminated between low, moderate, and high DAS28. Reliability: RAQoL and HAQ displayed good repeatability (ICC > 0.95) and internal consistency (Cronbach’s alpha > 0.90). Responsiveness: SF-36 bodily pain scale andVAS pain were responsive to both improvement and deterioration. Conclusion. All instruments were valid measures for HRQOL in RA. The RAQoL and HAQ dis- played the best reliability, while the SF-36 bodily pain scale andVAS pain were the most responsive. The choice of instrument should depend on the study objectives. (First Release May 15 2008; J Rheumatol 2008;35:1528–37) KeyIndexingTerms: RHEUMATOIDARTHRITIS HEALTH-RELATED QUALITY OF LIFE VALIDITY RELIABILITY RESPONSIVENESS From the Department of Rheumatology, Copenhagen University Hospital, Hvidovre; CAST, University of Southern Denmark, Odense; and Gråsten Gigthospital, University of Southern Denmark, Gråsten, Denmark. L.Linde,MD;M.Østergaard,MD,PhD,DMSc;M.L.Hetland,MD,PhD, Department of Rheumatology at Copenhagen University Hospital; J.Sørensen,MSc,CAST,UniversityofSouthernDenmark;K.Hørslev- Petersen, MD, DMSc, Gråsten Gigthospital. AddressreprintrequeststoDr.L.Linde,DepartmentofRheumatology, 232,KettegaardAllé30,DK-2650Hvidovre,Denmark. E-mail: louiselinde@dadlnet.dk Accepted for publication February 7, 2008. Rheumatoid arthritis (RA) is a chronic disabling disease affecting physical, mental, and social aspects of patients’ lives. Traditional clinical disease markers of RA such as joint counts and serum C-reactive protein (CRP) quantify some of the physical aspects of the disease, but fail to fully identify the broad spectrum of disease effects. Con- sequently, patient-reported outcome measures of health- related quality of life (HRQOL) have been developed to complement the traditional disease markers, and the impor- tance of such measures in determining improvement in clin- ical trials has been recognized by the American College of Rheumatology (ACR) and Outcome Measures in Rheuma- toid Arthritis Clinical Trials (OMERACT) 1 . Some studies have even suggested patient-reported outcome measures to be potentially more sensitive to a clinical change in RA than traditional disease markers 2,3 . HRQOL measurement instru- ments can be either generic (i.e., general or disease-inde- pendent), such as the Medical Outcomes Study Short Form- 36 Health Survey (SF-36), or disease-specific (designed for a specific disease), such as the RheumatoidArthritis Quality of Life Scale (RAQoL) 4 . HRQOL measures are now increasingly used in clinical trials of RA, but in order to draw conclusions from the results, the properties of the measurement instruments have to be evaluated in terms of validity, reliability, and responsiveness. The psychometric properties of SF-36 have been demon- strated in various populations, and it is widely used as a www.jrheum.org Downloaded on September 28, 2021 from