Choosing which AQoL instrument to use
Choose the instrument which has questions that cover what you want to measure:
| Instrument | Items | Completion time | Dimensions included |
| AQoL-8D |
35 |
less than
6 min |
Independent Living, Happiness, Mental Health, Coping, Relationships, Self Worth, Pain, Senses |
| AQoL-7D |
26 |
3-4 min |
Independent Living, Mental Health, Coping, Relationships, Pain, Senses, Visual Impairment |
| AQoL-6D |
20 |
2-3 min |
Independent Living, Mental Health, Coping, Relationships, Pain, Senses |
| AQoL-4D |
12 |
1-2 min |
Independent Living, Mental Health, Relationships, Senses
|
Psychometric or Utility?
As generic instruments, the AQoL questionnaires are applicable to all public health and clinical interventions, and can be used in different ways.
As a 'psychometric' measure: Each instrument can be used to derive a simple psychometric score for health related quality of life (HRQoL) and to provide profile scores on the different dimensions or items of the descriptive systems. The score is derived by adding the unweighted response order of each question.
As a 'utility' measure: When utilities are computed, these instruments can provide dimension scores and an overall index of the health state utility which can be used in economic evaluations, and specifically, cost-utility analysis requiring the computation of quality-adjusted life years (QALYs). The ‘utilities’ are, in effect, preference weights and final utility scores should reflect peoples’ preferences more accurately than unweighted aggregates.
The following example question about feeling sad demonstrates the two ways of scoring:
Transformations between instruments
Results from different instruments must differ (this is observable between the different MAU instruments already in use). Spring, balance and electronic scales may all produce the same weight, but may only if they are calibrated to do so. For this reason the AQoL team at the Centre for Health Economics is producing transformations between different instruments.
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