title: Comparison of the preference-based EQ-5D-5L and SF-6D in patients with end-stage renal disease (ESRD).
abstract: OBJECTIVE
  The objective of this study was to compare the performance of the 5-level EuroQol 5-dimension (EQ-5D-5L) and the Short Form 6-dimension (SF-6D) instruments in assessing patients with end-stage renal disease (ESRD) in Singapore.
  
  
  METHODS
  In a cross-sectional study, ESRD patients attending a tertiary hospital were interviewed using a battery of questionnaires including the EQ-5D-5L, the kidney disease quality of life instrument (KDQOL-36), and questions assessing dialysis history and socio-demographic characteristics. We reviewed patients' medical records for their clinical information. We assessed the construct validity of the EQ-5D-5L and SF-6D index scores and compared their ability to distinguish between patients differing in health status and the magnitude of between-group difference they quantified.
  
  
  RESULTS
  One hundred and fifty ESRD patients on dialysis (mean age, 60.1 years; female, 48.7%) participated in the study. Both EQ-5D-5L and SF-6D demonstrated satisfactory known-groups validity; the EQ-5D-5L was more sensitive to differences in clinical outcomes and the SF-6D was more sensitive to differences in health outcomes measured by KDQOL scales. The intraclass correlation coefficient between the measures was 0.36. The differences in the EQ-5D-5L index score for patients in better and worse health status were greater than those measured by the SF-6D index score.
  
  
  CONCLUSIONS
  Both EQ-5D-5L and SF-6D are valid instruments for assessing ESRD patients. However, the two preference-based measures cannot be used interchangeably and it appears that EQ-5D-5L would lead to more favorable cost-effectiveness results than SF-6D if they are used in economic evaluations of interventions for ESRD.
authors.affiliation: Saw Swee Hock School of Public Health, National University of Singapore, 12 Science Drive 2, MD 1, Singapore, 117549, Singapore.
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.affiliation: Division of Nephrology, University Medicine Cluster, National University Health System, 1E Kent Ridge Road, NUHS Tower Block, Singapore, 119228, Singapore.
authors.forename: Titus
authors.initials: T
authors.lastname: Lau
authors.affiliation: Division of Nephrology, University Medicine Cluster, National University Health System, 1E Kent Ridge Road, NUHS Tower Block, Singapore, 119228, Singapore.
authors.forename: Evan
authors.initials: E
authors.lastname: Lee
authors.affiliation: Division of Nephrology, University Medicine Cluster, National University Health System, 1E Kent Ridge Road, NUHS Tower Block, Singapore, 119228, Singapore.
authors.forename: A
authors.initials: A
authors.lastname: Vathsala
authors.affiliation: Saw Swee Hock School of Public Health, National University of Singapore, 12 Science Drive 2, MD 1, Singapore, 117549, Singapore.
authors.forename: Kee Seng
authors.initials: KS
authors.lastname: Chia
authors.affiliation: Saw Swee Hock School of Public Health, National University of Singapore, 12 Science Drive 2, MD 1, Singapore, 117549, Singapore. nan_luo@nuhs.edu.sg.
authors.forename: Nan
authors.initials: N
authors.lastname: Luo
mesh_terms: D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006801:Humans; D007407:Interviews as Topic; D007676:Kidney Failure, Chronic / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D057240:Patient Preference; D011788:Quality of Life; D015203:Reproducibility of Results; D012846:Singapore; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires / Q000592:standards*; D062606:Tertiary Care Centers
keywords: Discriminative ability; EQ-5D-5L; ESRD; SF-6D