Psychometric Performance of EQ-5D-5L and VILL-UI, a New Condition-Specific Preference-Weighted Measure, in Patients With Age-Related Macular Degeneration: A Macustar Study Report

Speaker(s)

Rowen D1, Carlton J2, McDool E3, Terheyden JH4, Finger RP4
1University of Sheffield, Sheffield, UK, 2University of Sheffield, Sheffield, YOR, UK, 3University of Sheffield, Sheffield, South Yorkshire, UK, 4University of Bonn, Bonn, North Rhine-Westphalia, Germany

Presentation Documents

OBJECTIVES: The aim of this study is to assess and compare the psychometric performance of a newly developed preference-weighted measure for patients with age related macular degeneration (AMD), VILL-UI, and EQ-5D-5L in patients with AMD. Understanding the psychometric performance of preference-weighted measures is useful to inform decisions around the selection of measures and understanding and interpretation of their results.

METHODS: EQ-5D-5L and VILL-UI utilities were generated using both UK and German value sets using the MACUSTAR cross-sectional and longitudinal data at baseline, 12 months, 24 months and 36 months. Assessments examine feasibility, convergent validity and known-group validity. Responsiveness could not be assessed as the utility data cannot be linked to an intervention.

RESULTS: Both VILL-UI and EQ-5D-5L are feasible for generating utilities for patients with AMD. VILL-UI has higher levels of missing data. EQ-5D-5L has high ceiling effects, meaning a large proportion of respondents report the highest values possible (between 52.2% and 95.4% of observations with no problems across different dimensions at baseline), whereas VILL-UI does not suffer from floor or ceiling effects. Convergent validity between EQ-5D-5L and VILL-UI utility values and dimensions where a relationship would be expected are low, divergent validity where relationships would not be expected were confirmed. VILL-UI performed better for known-group validity than EQ-5D-5L across severity groups for visual acuity and visual dysfunction.

CONCLUSIONS: Whilst EQ-5D-5L is feasible and has low rates of missing data, VILL-UI has superior performance for known-group validity and fewer ceiling effects but higher missing data. The measures capture different aspects of health-related quality of life, as evidenced by divergent validity and low convergent validity.

Code

EE391

Topic

Patient-Centered Research

Topic Subcategory

Health State Utilities, Patient-reported Outcomes & Quality of Life Outcomes

Disease

No Additional Disease & Conditions/Specialized Treatment Areas, Sensory System Disorders (Ear, Eye, Dental, Skin)