Mapping EQ-5D-5L Utilities in Dementia: Integrating Self and Proxy Reports

Area of Science:

• Gerontology
• Health Economics
• Psychometrics

Background:

• The EQ-5D is a standard measure for health-related quality of life (HRQoL) in dementia research.
• Cognitive impairment in dementia often requires proxy (caregiver) reports, leading to discrepancies with patient (person with dementia - PwD) self-reports.
• Existing methods struggle to reconcile these differing perspectives for comprehensive HRQoL assessment.

Purpose of the Study:

• To develop and evaluate predictive models for combined EQ-5D utility values using both PwD and proxy data.
• To assess if utility values can be accurately predicted when data from only one respondent type is available.
• To enhance HRQoL assessments in dementia research by integrating diverse data sources.

Main Methods:

• Utilized data from two dementia studies (ACTIFCARE and EPIC) to build mapping models.
• Employed ordered probit models for response mapping to predict EQ-5D-5L responses from single respondent types.
• Evaluated model performance by comparing predicted and observed data across different dementia severity levels.

Main Results:

• Combined utility values more accurately reflected HRQoL and detected health status changes.
• Proxy data effectively predicted PwD responses for specific EQ-5D-5L dimensions.
• Mapping models showed good performance in mild-to-moderate dementia but were less accurate in severe dementia due to data limitations.

Conclusions:

• Integrated utility values enhance HRQoL assessments and sensitivity to health changes in mild-to-moderate dementia.
• Developed models support the use of combined utility values in economic evaluations of dementia interventions.
• Further research is needed to address data limitations in severe dementia.