Comparison of the preference-based EQ-5D-5L and SF-6D in patients with end-stage renal disease (ESRD)

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.

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.

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.

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.