Estimating a Minimal Important Difference for the EQ-5D-5L Utility Index in Dialysis Patients

Amanda N Siriwardana; Anna T Hoffman; Rachael L Morton; Brendan Smyth; Mark A Brown

doi:10.1016/j.jval.2024.01.011

Estimating a Minimal Important Difference for the EQ-5D-5L Utility Index in Dialysis Patients

Value Health. 2024 Apr;27(4):469-477. doi: 10.1016/j.jval.2024.01.011. Epub 2024 Feb 1.

Authors

Amanda N Siriwardana¹, Anna T Hoffman², Rachael L Morton³, Brendan Smyth⁴, Mark A Brown⁵

Affiliations

¹ Renal and Metabolic Division, The George Institute for Global Health, Sydney, NSW, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, Australia; Department of Renal Medicine, Royal North Shore Hospital, Sydney, NSW, Australia. Electronic address: asir3810@uni.sydney.edu.au.
² Department of Renal Medicine, St George Hospital, Sydney, NSW, Australia.
³ NHMRC Clinical Trials Centre, University of Sydney, Sydney, NSW, Australia.
⁴ Department of Renal Medicine, St George Hospital, Sydney, NSW, Australia; NHMRC Clinical Trials Centre, University of Sydney, Sydney, NSW, Australia.
⁵ Department of Renal Medicine, St George Hospital, Sydney, NSW, Australia; Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia.

PMID: 38307389
DOI: 10.1016/j.jval.2024.01.011

Abstract

Objectives: The EQ-5D-5L is a commonly used health-related quality of life instrument for evaluating interventions in patients receiving dialysis; however, the minimal important difference (MID) that constitutes a meaningful treatment effect for this population has not been established. This study aims to estimate the MID for the EQ-5D-5L utility index in dialysis patients.

Methods: 6-monthly EQ-5D-5L measurements were collected from adult dialysis patients between April 2017 and November 2020 at a renal network in Sydney, Australia. EQ-VAS and Integrated Palliative care Outcome Scale Renal symptom burden scores were collected simultaneously and used as anchors. MID estimates for the EQ-5D-5L utility index were derived using anchor-based and distribution-based methods.

Results: A total of 352 patients with ≥1 EQ-5D-5L observation were included, constituting 1127 observations. Mean EQ-5D-5L utility index at baseline was 0.719 (SD ± 0.267), and mean EQ-5D-5L utility decreased over time by -0.017 per year (95% CI -0.029 to -0.006, P = .004). Using cross-sectional anchor-based methods, MID estimates ranged from 0.073 to 0.107. Using longitudinal anchor-based methods, MID for improvement and deterioration ranged from 0.046 to 0.079 and -0.111 to -0.048, respectively. Using receiver operating characteristic curves, MID for improvement and deterioration ranged from 0.037 to 0.122 and -0.074 to -0.063, respectively. MID estimates from distribution-based methods were consistent with anchor-based estimates.

Conclusions: Anchor-based and distribution-based approaches provided EQ-5D-5L utility index MID estimates ranging from 0.034 to 0.134. These estimates can inform the target difference or "effect size" for clinical trial design among dialysis populations.

Keywords: EQ-5D-5L; health-related quality of life; minimal important difference; patient outcome assessment; renal dialysis.

MeSH terms

Adult
Cross-Sectional Studies
Humans
Psychometrics
Quality of Life*
Renal Dialysis*
Surveys and Questionnaires