The Validity and Responsiveness of Generic Utility Measures in Rheumatoid Arthritis: A Review

MARK J. HARRISON, LINDA M. DAVIES, NICK J. BANSBACK, MARY INGRAM, ASLAM H. ANIS, and DEBORAH P.M. SYMMONS

ABSTRACT.

Objective. Cost-utility analysis is increasingly important as healthcare providers aim to invest scarce resources in interventions offering the greatest health benefit. The ability to attach utility values to health states is essential, and is increasingly performed using generic scales. However, the evidence regarding the validity of generic utility scales in rheumatoid arthritis (RA) is unclear. We summarize and review evidence on the validity and comparative performance of generic utility scales in RA.

Methods. We searched the English-language medical literature for studies using utilities in RA between 1980 and mid-2006. Reports describing primary evidence of the validity or performance of a generic utility scale in RA were selected, summarized, and reviewed using the OMERACT filter.

Results. In total 923 articles were identified, of which 228 reported the use of utility scales in RA; 26 studies related to the validation or evidence of generic utility scales in RA, the EQ-5D, Health Utility Index-2 (HUI2) and HUI3, SF-6D, and Quality of Well-Being Scale. The EQ-5D, HUI2 and HUI3, and SF-6D all have consistent evidence of construct validity and responsiveness in RA, but each has limitations.

Conclusion. The EQ-5D and HUI3 have been the most extensively studied instruments and show validity and responsiveness for use in RA, but both instruments have limitations. The SF-6D is relatively new and appears to have potential for use in milder RA, but needs further evaluation. More longitudinal head-to-head evaluation of measures is needed across the spectrum of RA disease severity to further investigate their comparative properties, and to seek consensus on the best utility measure for use in economic evaluation. (First Release Feb 15 2008; J Rheumatol 2008;35:592-602)

Key Indexing Terms:

RHEUMATOID ARTHRITIS
UTILITIES
QUALITY OF LIFE
QUALITY-ADJUSTED LIFE-YEARS
COST-EFFECTIVENESS
VALIDITY

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From the Arthritis Research Campaign (arc) Epidemiology Unit, and Health Economics Research at Manchester (HERMAN), The University of Manchester, Manchester, UK; Centre for Health Evaluation and Outcome Sciences, St. Paul's Hospital, Vancouver, British Columbia; and Department of Healthcare and Epidemiology, University of British Columbia, Vancouver, British Columbia, Canada.

M.J. Harrison, MSc, Research Assistant; M. Ingram, MSc, Librarian-Information Officer; D.P.M. Symmons, MD, Professor of Rheumatology and Musculoskeletal Epidemiology, Arthritis Research Campaign (arc) Epidemiology Unit; L.M. Davies, MSc, Reader, Director of Health Economics Research, Health Economics Research at Manchester; N.J. Bansback, MSc, Health Economist, Centre for Health Evaluation and Outcome Sciences, St. Paul's Hospital; A.H. Anis, PhD, Professor of Health Economics, Centre for Health Evaluation and Outcome Sciences, St. Paul's Hospital, and Department of Healthcare and Epidemiology, University of British Columbia.

Address reprint requests to Prof. D.P.M. Symmons, arc Epidemiology Unit, Stopford Building, The University of Manchester, Oxford Road, Manchester, M13 9PT, UK. E-mail: deborah.symmons@manchester.ac.uk

Accepted for publication November 17, 2007.

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