AQL-5D (Asthma Quality of Life Utility Index)
The AQL-5D is a tool that converts scores from the Asthma Quality of Life Questionnaire (AQLQ) into a single number representing the quality of life for people with asthma. This number can be used to compare health outcomes in economic evaluations of asthma treatments.
At a glance
Use when
Conducting economic evaluations of asthma interventions; when AQLQ data are available and utility values are needed for QALY calculation; when condition-specific sensitivity is preferred over generic measures
Avoid when
Comparing outcomes across different diseases; when a generic health-related quality of life measure is required; if dimensions of the AQL-5D do not align with the intervention's impact
Inputs
Asthma health states defined by the AQL-5D (5 dimensions, 5 levels each), typically derived from the AQLQ
Outputs
Preference-based utility index (single value between 0 and 1) representing health state valuation for use in QALY calculations
How it works
The AQL-5D is a preference-based index derived from the Asthma Quality of Life Questionnaire (AQLQ), consisting of five dimensions reflecting asthma-specific health states. Health state values were elicited from 307 members of the UK general population using the time trade-off technique. A main effects model adjusted for consistency was found to best predict utility scores across the 3,125 possible health states, with a mean absolute error of 0.047. The index enables the calculation of quality-adjusted life years (QALYs) in asthma-specific economic evaluations.
- HTA domains
- Patient and Social Aspects
- Categories
- HRQoL
- Assumptions
- Health state valuations reflect societal preferences; the AQL-5D dimensions adequately capture asthma-specific quality of life; the main effects model sufficiently represents interactions between dimensions
- Strengths
- First asthma-specific preference-based measure derived from a validated HRQoL instrument; enables economic evaluation using AQLQ data; good predictive accuracy with low mean absolute error; developed using general population valuations
- Limitations
- Limited ability to make cross-disease comparisons due to condition-specific nature; potential unreliability in model estimates due to low number of valuations per state; does not capture all aspects of health relevant outside asthma
- Also known as
- AQL-5D, Asthma Quality of Life Utility Index
Questions this answers
- › How can asthma-specific health states be converted into utility values for economic evaluation?
- › What is the impact of asthma on patients' quality of life in terms of preference-based measures?
- › How do members of the general population value different asthma health states?
- › Can the AQLQ be used to generate QALYs for cost-utility analyses?
- › What model best predicts utility values from the AQL-5D dimensions?
- › How consistent are utility values across different levels of asthma health states?
References & sources
Similar by meaning
- Mapping EQ-5D-5L utility scores from the severe asthma questionnaire in the SHARP CRC registry
- AQoL-8D (Assessment of Quality of Life - 8 Dimensions)
- Mapping the Severe Asthma Questionnaire to EQ-5D-5L health utility scores in the SHARP CRC registry
- Obtaining EQ-5D-5L utilities from the disease specific quality of life Alzheimer’s disease scale: development and results from a mapping study
- EQ-5D-Y-3L value sets
Beta record. Based on the original catalogue summary; primary-source enrichment pending.