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Quality of Life Research

, Volume 12, Issue 1, pp 87–92 | Cite as

Validity and reliability of the EQ-5D self-report questionnaire in English-speaking Asian patients with rheumatic diseases in Singapore

  • N. Luo
  • L.H. Chew
  • K.Y. Fong
  • D.R. Koh
  • S.C. Ng
  • K.H. Yoon
  • S. Vasoo
  • S.C. Li
  • J. Thumboo
Article

Abstract

Validity and reliability of a Singaporean English EQ-5D self-report questionnaire (EQ-5D) were evaluated among consecutive outpatients with rheumatic diseases attending a tertiary referral hospital in Singapore (a multi-ethnic, urban Asian country). Subjects were interviewed twice within a 2-week period using a standardized questionnaire containing the EQ-5D, Short Form 36 Health Survey (SF-36) and assessing demographic and psychosocial characteristics. To assess validity of the EQ-5D, 13 hypotheses relating responses to EQ-5D dimension/Visual Analogue Scale (EQ-VAS) to SF-36 scores or other variables were examined using the Mann–Whitney test, Kruskal–Wallis test, or Spearman's correlation coefficient. Test–retest reliability was assessed using Cohen's κ. Sixty-six subjects were studied (osteoarthritis: 9, rheumatoid arthritis: 26, systemic lupus erythematosus: 23, spondyloarthropathy: 8; female: 72.7%; mean age: 44.3 years). Ten of 13 a-priori hypotheses relating EQ-5D responses to external variables were fulfilled, supporting the validity of the EQ-5D. Cohen's κ for test–retest reliability (n = 52) ranged from 0.29 to 0.61. The Singaporean English EQ-5D appears to be valid in measuring quality of life in Singaporeans with rheumatic diseases; however, its reliability requires further investigation. These data provide a basis for further studies assessing the validity of the EQ-5D in Singapore.

Psychometrics Quality of life Reliability of results Rheumatic diseases Singapore 

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Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • N. Luo
    • 1
  • L.H. Chew
    • 2
  • K.Y. Fong
    • 3
    • 4
  • D.R. Koh
    • 3
    • 4
  • S.C. Ng
    • 4
  • K.H. Yoon
    • 3
    • 4
  • S. Vasoo
    • 4
  • S.C. Li
    • 1
  • J. Thumboo
    • 3
    • 4
  1. 1.Department of PharmacyNational University of SingaporeSingapore
  2. 2.School of Health SciencesNanyang PolytechnicSingapore
  3. 3.Department of MedicineNational University of SingaporeSingapore
  4. 4.Department of MedicineNational University HospitalSingapore

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