Concept Architecture
Concept
Theoretically, Indirect Elicitation is a health state utility assessment method in which preferences are estimated by administering a validated preference-based health-related quality of life instrument rather than asking respondents to value health states directly. It is founded on multi-attribute utility theory and uses previously derived societal preference weights to convert descriptive health states into utility values. The method exists to provide a standardised, reproducible and comparable approach to utility measurement for economic evaluation.
Mathematically, indirect elicitation has no universally recognised canonical mathematical formula. Utility values are generated by applying a validated scoring algorithm or country-specific value set to an individual's responses on a preference-based instrument. The mathematical framework maps combinations of health state responses onto a single utility index representing societal preferences for the reported health state.
In practice, indirect elicitation is implemented using validated preference-based instruments such as EQ-5D, HUI, SF-6D and AQoL. Respondents complete the descriptive questionnaire, after which published scoring algorithms are applied to estimate utility values for quality-adjusted life year calculation, cost-utility analysis and health technology assessment.
Purpose
Used to estimate health state utility values from validated preference-based health status instruments using established societal value sets for quality-adjusted life year estimation and economic evaluation.
Mathematical Formulae
Primary Formula
There is no universally recognised canonical mathematical formula.
Supporting Formulae
U = f(x?; ??)
where:
- U = estimated health state utility
- x? = vector of health state responses
- ?? = coefficients from the validated value set (tariff)
Related Mathematical Methods
- Multi-attribute utility theory
- Preference scoring algorithms
- Country-specific value set estimation
- Quality-adjusted life year (QALY) calculation
Example
A patient completes the EQ-5D-5L questionnaire and reports the health state 2-1-2-3-1. Applying the UK EQ-5D-5L value set produces a utility value of 0.742. This utility is subsequently combined with survival time to estimate QALYs in a cost-utility analysis comparing alternative interventions.
Excel Implementation
| Function | Example Formula | Health Economics Application |
|---|---|---|
| XLOOKUP | =XLOOKUP(A2,Tariff[HealthState],Tariff[Utility]) | Retrieves the utility value associated with a coded health state from a validated value set. |
| INDEX | =INDEX(Tariff[Utility],MATCH(A2,Tariff[HealthState],0)) | Returns the appropriate utility weight from a published tariff. |
| SUM | =SUM(B2:E2) | Combines scoring components where the published algorithm uses additive coefficients. |
VBA (Optional)
Automate the scoring of completed preference-based questionnaires by applying country-specific value sets to generate utility estimates.
Sources
- Drummond MF, Sculpher MJ, Claxton K, Stoddart GL, Torrance GW. Methods for the Economic Evaluation of Health Care Programmes. Oxford University Press.
- Briggs A, Claxton K, Sculpher M. Decision Modelling for Health Economic Evaluation. Oxford University Press.
- NICE. Health Technology Evaluation Manual.
- Brazier J, Ratcliffe J, Salomon JA, Tsuchiya A. Measuring and Valuing Health Benefits for Economic Evaluation. Oxford University Press.
- EuroQol Research Foundation. EQ-5D User Guides.
Related Concepts (2)
Library
Publications
1
Measuring and Valuing Health Benefits for Economic Evaluation — Brazier, Ratcliffe, Salomon & Tsuchiya, 2nd Edition ed., 2017 (Oxford University Press)
The comprehensive text on the measurement and valuation of health benefits for economic evaluation — defining health, valuation techniques (time trade-off, standard gamble), whose values to use, preference-based measures (EQ-5D, SF-6D), and the construction of QALYs.
BookView source →
Frequently Asked Questions (6)
What is indirect elicitation?
A health state valuation approach in which a descriptive questionnaire's responses are converted into a utility value using a pre-existing scoring algorithm.
Source: Torrance GW. Measurement of health state utilities for economic appraisal. Journal of Health Economics. 1986;5(1):1-30. doi:10.1016/0167-6296(86)90020-2.
What does indirect elicitation ask of a respondent?
Under indirect elicitation the respondent is not asked to value anything. They only describe their own health by answering a standard set of questions about problems on each dimension, and the valuation has already been done by a separate population sample whose judgements are stored in a scoring formula. The respondent's task is therefore classification rather than trade-off, which makes the method quick and undemanding to complete. Brazier and colleagues (2007) contrast this division of labour with direct methods.
Source: Brazier et al. 2007
How does indirect elicitation work?
In indirect elicitation, the respondent completes a standardised descriptive questionnaire, selecting a level on each dimension, and the resulting health state is scored using a value set that gives a utility to every state the instrument can describe. The value set is developed beforehand by eliciting valuations of a sample of states from a population and modelling them. Applying it converts the respondent's description into a utility without any direct valuation task for that respondent.
Source: Torrance 1986
What are the advantages of indirect elicitation?
Indirect elicitation is practical for routine use, since respondents need only describe their health on a short questionnaire rather than complete demanding valuation tasks, making it feasible to measure many patients quickly. It uses a consistent value set, so utilities are comparable across studies and populations, and it draws on population preferences elicited once and reused. This convenience and comparability make indirect instruments the standard way to obtain utilities in economic evaluation.
Source: Torrance 1986
What are the limitations of indirect elicitation?
Indirect elicitation values a state using a pre-existing value set rather than the respondent's own valuation, so it applies population preferences that may not match those of the individual or the specific context. It is limited to the states the instrument can describe, so health not captured by its dimensions is missed, and the value set may not exist for the relevant population. The utility therefore depends on the instrument and value set chosen.
Source: Torrance 1986
How does indirect elicitation differ from direct elicitation?
Indirect elicitation has the respondent describe their health and applies a pre-existing value set to assign the utility, whereas direct elicitation has the respondent value the state themselves through a task such as the standard gamble or time trade-off. The indirect approach is practical for routine measurement and yields comparable utilities, while the direct approach values the specific state as the respondent sees it. The indirect method is usual for data collection, the direct for developing value sets.
Source: Torrance 1986
Trust Record
Verified by Dr Darrin Baines
British health economist
Professional identity: darrinbaines.org
Verification date: 29 Aug 2025
Content version: 1.0.0
Canonical Identity
- Term code
- HE-EE-HU-042
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