FAQS
The EuroQol Office offers answers to frequently asked questions relating to the EQ-5D-3L, EQ-5D-5L, EQ-5D-Y-3L and EQ-5D-Y-5L instrument, registration procedure, licensing fees, copyright notice and quality control. Please click on a subject heading below to view questions and answers relating to your selection.
Translation certificates for Paper Self-Complete versions are applicable for all corresponding modes of administration and can be provided upon request. Translation certificates only confirm and reflect the most extensive translation procedure and will not be revised whenever minor or major modifications are being made which in itself does not change the procedure.
EQ-5D is used by scientists across the world in different settings and for many different diseases. It is used by academia (e.g. universities, research institutes), governments (national, regional, municipal), industry (e.g. pharmaceuticals, medical devices) and by hospitals and clinics (e.g. hospitals, GP practices). At an international level, the pharmaceutical industry and scientific groups are the foremost users of the instrument. EQ-5D is frequently used in (multinational) clinical trials by pharmaceutical companies.
Several valuation techniques have been used to generate these value sets: time trade-off (TTO), visual analogue scale (VAS), and more recently, discrete choice experiments (DCE).
Please contact the EuroQol office.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g.EQ-5D-5L health state 21143 represents a patient who indicates slight problems on the mobility dimension, no problems on the self-care and usual activities dimensions, severe pain or discomfort and moderate problems on the anxiety/depression dimension. These health states can be converted into a single index value using one of the standard EQ-5D-5L value sets. These value sets reflect the preferences of the general population. In contrast, the EQ VAS scores are self-reported and are therefore not representative of the general population. The EQ VAS self-rating records the respondent’s own assessment of their health status. Furthermore, the EQ VAS scores are anchored on 100 = the best health you can imagine and 0 = the worst health you can imagine, whereas the value sets are anchored on 11111 = 1 (representing full health) and dead = 0 and can therefore be used in QALY calculations.
EQ-5D is the name of the instrument and is not an acronym. EQ-5D is the correct term to use in print or verbally.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g. EQ-5D-5L health state 11313 represents a patient who indicates moderate problems on the usual activities and anxiety/depression dimensions and no problems on the remaining dimensions. Please note that this is just a ‘shorthand’ way of describing an EQ-5D health state; the numbers are simply code for the level in each dimension and have no arithmetic properties whatsoever. Therefore, they should not, for example, be added to give an overall score.
A member of the EuroQol Office team will confirm safe receipt of the Translation Request and provide you with feasibility information, an estimated timeline and corresponding Approval Letter for signature within 10 business days. After confirmation of receipt of the signed Approval Letter, EuroQol will initiate the translation project. Default timelines EQ translation process: 10 business days from confirmation of receipt Translation Request to estimated project timeline from specialist translation agencies 10 business days from confirmation of receipt signed Approval Letter to project initiation 5 months on average to project completion
Note: these are our default response times. The overall timeline is also determined by the responsiveness of our clients and available linguistic resources for the requested language/country/mode of administration.
When publishing results obtained with the EQ-5D-Y, the following key references can be used:
- Wille N, Badia X, Bonsel G, Burstrom K, Cavrini G, Devlin N, Egmar AC, Greiner W, Gusi N, Herdman M, Jelsma J. Development of the EQ-5D-Y: a child-friendly version of the EQ-5D. Qual Life Res 2010 Aug;19(6):875-886.
- Ravens-Sieberer U, Wille N, Badia X, Bonsel G, Burstrom K, Cavrini G, Devlin N, Egmar AC, Gusi N, Herdman M, J. Feasibility, reliability, and validity of the EQ-5D-Y: results from a multinational study. Qual Life Res 2010 Aug;19(6):887-897.
When publishing results obtained with the EQ-5D-5L, the following key references can be used:
- The EuroQol Group (1990). EuroQol-a new facility for the measurement of health-related quality of life. Health Policy 16(3):199-208.
- Brooks R (1996). EuroQol: the current state of play. Health Policy 37(1):53-72.
- Rabin, R., & de Charro, F (2001). EQ-5D: a measure of health status from the EuroQol Group. Annals of Medicine 33(5):337-343.
- Herdman M, Gudex C, Lloyd A, Janssen MF, Kind P, Parkin D, Bonsel G, Badia X (2011). Development and preliminary testing of the new five-level version of EQ-5D (EQ-5D-5L). Quality of Life Research 20(10):1727-36.
- Janssen MF, Pickard AS, Golicki D, Gudex C, Niewada M, Scalone L, Swinburn P, Busschbach J (2013). Measurement properties of the EQ-5D-5L compared to the EQ-5D-3L across eight patient groups: a multi-country study. Quality of Life Research 22(7):1717-27.
- Buchholz I, Janssen MF, Kohlmann T, Feng YS (2018). A systematic review of studies comparing the measurement properties of the three-level and five-level versions of the EQ-5D. Pharmacoeconomics 36(6):645-661.
- Janssen MF, Bonsel GJ, Luo N (2018). Is EQ-5D-5L Better Than EQ-5D-3L? A Head-to-Head comparison of descriptive systems and value sets from seven countries/regions. Pharmacoeconomics 36(6):675-697.
Until recently, no value sets were available for EQ-5D-Y-3L because research showed that the approach used to value EQ-5D-3L health states for use in adult populations was not appropriate when valuing EQ-5D-Y-3L health states for use in economic evaluations of healthcare interventions for paediatric-age populations. Evidence has showed that health states are valued differently when used to describe an adult compared to a child, that valuation techniques suitable for valuing ‘adult’ health states may be unsuitable for valuing ‘youth’ health states, and that health state values are affected by the wording used in the instrument (the wording of EQ-5D-Y-3L health states differs somewhat from that of EQ-5D-3L health states). Consequently, EQ-5D-3L value sets should not be used to assign values to EQ-5D-Y-3L health states.
To undertake a utility analysis, you will need to use a value set. Generally speaking, utility analysis requires a value set based on preferences from a general population. The rationale behind this is that the values are supposed to reflect the preferences of local taxpayers and potential receivers of healthcare. The EQ-5D value sets are therefore based on the values of the general population.
If you need to obtain health state utility values for the EQ-5D-5L, the recommendation is to use the United States EQ-5D-5L value set from Pickard et al. (2019) as the United Kingdom valuation study is currently ongoing. If you need to obtain health state utility values for the EQ-5D-3L, it is recommended to use the United Kingdom value set from Dolan et al. (2002).
A standardized valuation study protocol (called EQ-VT) was developed by the EuroQol Group to create standard value sets for the EQ-5D-5L. This protocol is based on the use of the composite time trade-off (cTTO) valuation technique, supplemented by a discrete choice experiment (DCE). We recommend EQ-5D-5L users to use the standard value sets, as these were produced with the EuroQol Group’s standardised valuation technology EQ-VT.
Several valuation techniques have been used to generate these value sets: time trade-off (TTO), visual analogue scale (VAS), and more recently, discrete choice experiments (DCE).
The time trade-off (TTO), visual analogue scale (VAS) and discrete choice experiment (DCE) value sets differ in the technique used to elicit the values for the models.
In the TTO task, respondents are asked to imagine they live in a certain suboptimal health state for 10 years and then to specify the amount of time they would be willing to give up to live in full health instead. For example, someone might consider that 8 years in full health is equivalent to 10 years in the suboptimal health state.
The VAS technique asks people to indicate where they think a health state should be positioned on a vertical thermometer-like scale ranging from best imaginable health to worst imaginable health.
The DCE asks people to choose between two (or more) health states of varying severity across the five EQ-5D health domains (e.g. which is better, state A [32233] or state B [32321]?).
There has been much discussion about the theoretical and empirical properties of these three methods, and whether it is justified to calculate QALYs using values based on these methods, although all three techniques have been used to calculate QALYs. Currently, EQ-5D-5L value sets which are developed using the EQ-VT platform are based either on a combination of TTO and DCE values, or on TTO values only.
Please note that this is a large subject area and the brief answer provided above includes minimal details. For further information, the reader is encouraged to review the literature.
The responses to the five EQ-5D dimensions (i.e. an EQ-5D health state or profile) can be converted into a single number called an index value. The index value reflects how good or bad the health state is according to the preferences of the general population of a country/region. The collection of index values for all possible EQ-5D states is called a value set.
Please see this webpage on choosing a value set. Many factors determine if another country’s value set can be used, such as geography, religion, language, level of development of the country, healthcare system etc. In addition, local HTA guidelines may come into play. Therefore, it is advised to contact local regulatory authorities about their requirements.
Please note, if a standard EQ-5D-5L value set is not available for your country, then an interim “crosswalk” value set can be used, if available. A crosswalk value set is one that has been created for the EQ-5D-3L and then adapted to fit the EQ-5D-5L descriptive system. More information on the crosswalk can be found here.
Data on EQ-5D health states gathered in the context of a multinational trial may be converted into a single summary index using one of the available EQ-5D-3L value sets. There are different options available to do this using appropriate value sets, however, the choice depends on the context in which researchers or decision makers will use the information.
In cases where data from a multinational trial are to be used to inform decision makers in a specific country, it seems reasonable to expect decision makers to be interested primarily in value sets that reflect the values for EQ-5D-3L health states in that specific country. For example, if applications for reimbursement of a drug are rolled out from country to country, then country-specific value sets should be applied and reported in each pharmaco-economic report. This is no different from the requirement to use country-specific costs. In the absence of a country-specific value set, the researcher should select another set of values for a population that most closely approximates that country.
Sometimes information about utilities is required to inform researchers or decision makers in an international context. In these instances, it is probably more appropriate to apply one value set to all the EQ-5D health state data. The decision about which value set to use will depend on whether the relevant decision-making body in each country specifies any requirements or preferences in regard to the methodology used in different contexts (e.g. TTO, standard gamble (SG), VAS or discrete choice modelling (DCM)). These guidelines are the topic of an international ongoing debate, but the EuroQol Group is planning to provide a summary of health-care decision-making bodies internationally, including their stated requirements regarding the valuation of health states.
Detailed information regarding the EQ-5D-3L valuation protocols, guidelines for choice of value set and tables of all available value sets have been published by Springer in: EuroQol Group Monograph series: Volume 2: EQ-5D value sets: inventory, comparative review and user guide’ (see section 8 for more information). Chapter 4 by Nancy Devlin and David Parkin will be of special interest to researchers pondering the issue of which value set to use.
Please contact our scientific director.
To undertake a utility analysis, you will need to use a value set. Generally speaking, utility analysis requires a value set based on preferences from a general population. The rationale behind this is that the values are supposed to reflect the preferences of local taxpayers and potential receivers of healthcare. The EQ-5D value sets are therefore based on the values of the general population.
EQ-5D is used by scientists across the world in different settings and for many different diseases. It is used by academia (e.g. universities, research institutes), governments (national, regional, municipal), industry (e.g. pharmaceuticals, medical devices) and by hospitals and clinics (e.g. hospitals, GP practices). At an international level, the pharmaceutical industry and scientific groups are the foremost users of the instrument. EQ-5D is frequently used in (multinational) clinical trials by pharmaceutical companies.
There is growing evidence on the comparative psychometric performance of the EQ-5D-3L and EQ-5D-5L descriptive systems. A published systematic review by Buchholz and colleagues found that the 5-level version performed better, or at least the same in terms of measurement properties when compared to the 3-level version. This review supports the use of both the 3-level and 5-level versions in a broad range of patients, populations and countries/regions and shows that the EQ-5D-5L is to be preferred from a psychometric point of view. In addition, the EQ-5D-5L is accompanied by recent and up to date value sets, derived using the standardized EQ-VT protocol, for a large number of countries all around the world. These value sets are likely to be more appropriate compared to value sets that were derived before the introduction of the EQ-VT protocol.
Please contact the EuroQol office.
The time trade-off (TTO), visual analogue scale (VAS) and discrete choice experiment (DCE) value sets differ in the technique used to elicit the values for the models.
In the TTO task, respondents are asked to imagine they live in a certain suboptimal health state for 10 years and then to specify the amount of time they would be willing to give up to live in full health instead. For example, someone might consider that 8 years in full health is equivalent to 10 years in the suboptimal health state.
The VAS technique asks people to indicate where they think a health state should be positioned on a vertical thermometer-like scale ranging from best imaginable health to worst imaginable health.
The DCE asks people to choose between two (or more) health states of varying severity across the five EQ-5D health domains (e.g. which is better, state A [32233] or state B [32321]?).
There has been much discussion about the theoretical and empirical properties of these three methods, and whether it is justified to calculate QALYs using values based on these methods, although all three techniques have been used to calculate QALYs. Currently, EQ-5D-5L value sets which are developed using the EQ-VT platform are based either on a combination of TTO and DCE values, or on TTO values only.
Please note that this is a large subject area and the brief answer provided above includes minimal details. For further information, the reader is encouraged to review the literature.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g.EQ-5D-5L health state 21143 represents a patient who indicates slight problems on the mobility dimension, no problems on the self-care and usual activities dimensions, severe pain or discomfort and moderate problems on the anxiety/depression dimension. These health states can be converted into a single index value using one of the standard EQ-5D-5L value sets. These value sets reflect the preferences of the general population. In contrast, the EQ VAS scores are self-reported and are therefore not representative of the general population. The EQ VAS self-rating records the respondent’s own assessment of their health status. Furthermore, the EQ VAS scores are anchored on 100 = the best health you can imagine and 0 = the worst health you can imagine, whereas the value sets are anchored on 11111 = 1 (representing full health) and dead = 0 and can therefore be used in QALY calculations.
The responses to the five EQ-5D dimensions (i.e. an EQ-5D health state or profile) can be converted into a single number called an index value. The index value reflects how good or bad the health state is according to the preferences of the general population of a country/region. The collection of index values for all possible EQ-5D states is called a value set.
EQ-5D is the name of the instrument and is not an acronym. EQ-5D is the correct term to use in print or verbally.
The EuroQol Office team will determine if a license agreement needs to be drawn up and whether a license fee is applicable, in accordance with our EQ-5D User License Policy.
EQ-5D paper versions will be provided as a Word document. For electronic versions, an Excel sheet will be provided with the EQ-5D labels, together with a document describing the EQ-5D electronic representation standards. The EQ-5D Demo versions on the website were created fully in line with our standards, so you can check how EQ-5D should look like on your system.
Please see this webpage on choosing a value set. Many factors determine if another country’s value set can be used, such as geography, religion, language, level of development of the country, healthcare system etc. In addition, local HTA guidelines may come into play. Therefore, it is advised to contact local regulatory authorities about their requirements.
Please note, if a standard EQ-5D-5L value set is not available for your country, then an interim “crosswalk” value set can be used, if available. A crosswalk value set is one that has been created for the EQ-5D-3L and then adapted to fit the EQ-5D-5L descriptive system. More information on the crosswalk can be found here.
To undertake a utility analysis, you will need to use a value set. Generally speaking, utility analysis requires a value set based on preferences from a general population. The rationale behind this is that the values are supposed to reflect the preferences of local taxpayers and potential receivers of healthcare. The EQ-5D value sets are therefore based on the values of the general population.
EQ-5D is used by scientists across the world in different settings and for many different diseases. It is used by academia (e.g. universities, research institutes), governments (national, regional, municipal), industry (e.g. pharmaceuticals, medical devices) and by hospitals and clinics (e.g. hospitals, GP practices). At an international level, the pharmaceutical industry and scientific groups are the foremost users of the instrument. EQ-5D is frequently used in (multinational) clinical trials by pharmaceutical companies.
A standardized valuation study protocol (called EQ-VT) was developed by the EuroQol Group to create standard value sets for the EQ-5D-5L. This protocol is based on the use of the composite time trade-off (cTTO) valuation technique, supplemented by a discrete choice experiment (DCE). We recommend EQ-5D-5L users to use the standard value sets, as these were produced with the EuroQol Group’s standardised valuation technology EQ-VT.
Please note that in the UK, as an interim measure whilst a new UK EQ-5D-5L value set is being developed, a different mapping function is recommended for use in submissions to NICE (see EQ-5D-5L valuation webpage) for more information.
There is growing evidence on the comparative psychometric performance of the EQ-5D-3L and EQ-5D-5L descriptive systems. A published systematic review by Buchholz and colleagues found that the 5-level version performed better, or at least the same in terms of measurement properties when compared to the 3-level version. This review supports the use of both the 3-level and 5-level versions in a broad range of patients, populations and countries/regions and shows that the EQ-5D-5L is to be preferred from a psychometric point of view. In addition, the EQ-5D-5L is accompanied by recent and up to date value sets, derived using the standardized EQ-VT protocol, for a large number of countries all around the world. These value sets are likely to be more appropriate compared to value sets that were derived before the introduction of the EQ-VT protocol.
Please contact the EuroQol office.
The time trade-off (TTO), visual analogue scale (VAS) and discrete choice experiment (DCE) value sets differ in the technique used to elicit the values for the models.
In the TTO task, respondents are asked to imagine they live in a certain suboptimal health state for 10 years and then to specify the amount of time they would be willing to give up to live in full health instead. For example, someone might consider that 8 years in full health is equivalent to 10 years in the suboptimal health state.
The VAS technique asks people to indicate where they think a health state should be positioned on a vertical thermometer-like scale ranging from best imaginable health to worst imaginable health.
The DCE asks people to choose between two (or more) health states of varying severity across the five EQ-5D health domains (e.g. which is better, state A [32233] or state B [32321]?).
There has been much discussion about the theoretical and empirical properties of these three methods, and whether it is justified to calculate QALYs using values based on these methods, although all three techniques have been used to calculate QALYs. Currently, EQ-5D-5L value sets which are developed using the EQ-VT platform are based either on a combination of TTO and DCE values, or on TTO values only.
Please note that this is a large subject area and the brief answer provided above includes minimal details. For further information, the reader is encouraged to review the literature.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g.EQ-5D-5L health state 21143 represents a patient who indicates slight problems on the mobility dimension, no problems on the self-care and usual activities dimensions, severe pain or discomfort and moderate problems on the anxiety/depression dimension. These health states can be converted into a single index value using one of the standard EQ-5D-5L value sets. These value sets reflect the preferences of the general population. In contrast, the EQ VAS scores are self-reported and are therefore not representative of the general population. The EQ VAS self-rating records the respondent’s own assessment of their health status. Furthermore, the EQ VAS scores are anchored on 100 = the best health you can imagine and 0 = the worst health you can imagine, whereas the value sets are anchored on 11111 = 1 (representing full health) and dead = 0 and can therefore be used in QALY calculations.
The responses to the five EQ-5D dimensions (i.e. an EQ-5D health state or profile) can be converted into a single number called an index value. The index value reflects how good or bad the health state is according to the preferences of the general population of a country/region. The collection of index values for all possible EQ-5D states is called a value set.
EQ-5D is the name of the instrument and is not an acronym. EQ-5D is the correct term to use in print or verbally.
Until recently, no value sets were available for EQ-5D-Y-3L because research showed that the approach used to value EQ-5D-3L health states for use in adult populations was not appropriate when valuing EQ-5D-Y-3L health states for use in economic evaluations of healthcare interventions for paediatric-age populations. Evidence has showed that health states are valued differently when used to describe an adult compared to a child, that valuation techniques suitable for valuing ‘adult’ health states may be unsuitable for valuing ‘youth’ health states, and that health state values are affected by the wording used in the instrument (the wording of EQ-5D-Y-3L health states differs somewhat from that of EQ-5D-3L health states). Consequently, EQ-5D-3L value sets should not be used to assign values to EQ-5D-Y-3L health states.
To undertake a utility analysis, you will need to use a value set. Generally speaking, utility analysis requires a value set based on preferences from a general population. The rationale behind this is that the values are supposed to reflect the preferences of local taxpayers and potential receivers of healthcare. The EQ-5D value sets are therefore based on the values of the general population.
EQ-5D is used by scientists across the world in different settings and for many different diseases. It is used by academia (e.g. universities, research institutes), governments (national, regional, municipal), industry (e.g. pharmaceuticals, medical devices) and by hospitals and clinics (e.g. hospitals, GP practices). At an international level, the pharmaceutical industry and scientific groups are the foremost users of the instrument. EQ-5D is frequently used in (multinational) clinical trials by pharmaceutical companies.
Please contact the EuroQol office.
The time trade-off (TTO), visual analogue scale (VAS) and discrete choice experiment (DCE) value sets differ in the technique used to elicit the values for the models.
In the TTO task, respondents are asked to imagine they live in a certain suboptimal health state for 10 years and then to specify the amount of time they would be willing to give up to live in full health instead. For example, someone might consider that 8 years in full health is equivalent to 10 years in the suboptimal health state.
The VAS technique asks people to indicate where they think a health state should be positioned on a vertical thermometer-like scale ranging from best imaginable health to worst imaginable health.
The DCE asks people to choose between two (or more) health states of varying severity across the five EQ-5D health domains (e.g. which is better, state A [32233] or state B [32321]?).
There has been much discussion about the theoretical and empirical properties of these three methods, and whether it is justified to calculate QALYs using values based on these methods, although all three techniques have been used to calculate QALYs. Currently, EQ-5D-5L value sets which are developed using the EQ-VT platform are based either on a combination of TTO and DCE values, or on TTO values only.
Please note that this is a large subject area and the brief answer provided above includes minimal details. For further information, the reader is encouraged to review the literature.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g.EQ-5D-5L health state 21143 represents a patient who indicates slight problems on the mobility dimension, no problems on the self-care and usual activities dimensions, severe pain or discomfort and moderate problems on the anxiety/depression dimension. These health states can be converted into a single index value using one of the standard EQ-5D-5L value sets. These value sets reflect the preferences of the general population. In contrast, the EQ VAS scores are self-reported and are therefore not representative of the general population. The EQ VAS self-rating records the respondent’s own assessment of their health status. Furthermore, the EQ VAS scores are anchored on 100 = the best health you can imagine and 0 = the worst health you can imagine, whereas the value sets are anchored on 11111 = 1 (representing full health) and dead = 0 and can therefore be used in QALY calculations.
The responses to the five EQ-5D dimensions (i.e. an EQ-5D health state or profile) can be converted into a single number called an index value. The index value reflects how good or bad the health state is according to the preferences of the general population of a country/region. The collection of index values for all possible EQ-5D states is called a value set.
EQ-5D is the name of the instrument and is not an acronym. EQ-5D is the correct term to use in print or verbally.
The EuroQol Office team will determine if a license agreement needs to be drawn up and whether a license fee is applicable, in accordance with our EQ-5D User License Policy.
EQ-5D paper versions will be provided as a Word document. For electronic versions, an Excel sheet will be provided with the EQ-5D labels, together with a document describing the EQ-5D electronic representation standards. The EQ-5D Demo versions on the website were created fully in line with our standards, so you can check how EQ-5D should look like on your system.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g. EQ-5D-5L health state 11313 represents a patient who indicates moderate problems on the usual activities and anxiety/depression dimensions and no problems on the remaining dimensions. Please note that this is just a ‘shorthand’ way of describing an EQ-5D health state; the numbers are simply code for the level in each dimension and have no arithmetic properties whatsoever. Therefore, they should not, for example, be added to give an overall score.
A mapping study has been commissioned which will allow EQ-5D-Y-5L outcomes to be mapped to existing EQ-5D-Y-3L value sets. Until the results of that study become available, it should be remembered that there are many ways of analysing EQ-5D-Y-5L data and most of them do not require the generation of EQ-5D values (i.e. utilities, or preference weights). For more details on how to analyse EQ-5D-Y-5L data, please see the User Guide. For more information on how to analyse and report EQ-5D data in general, a comprehensive methodological guide has been published.
The EQ-5D-Y-5L provides respondents with a greater range of response options than the EQ-5D-Y-3L allowing them to describe their health more precisely. Expanding the number of severity response levels in each dimension reduces ceiling effects and improves the sensitivity of the measure in some conditions.
The five-level structure of the EQ-5D-Y-5L is also more comparable to the adult EQ-5D-5L, which leads to a smoother transition between youth and adult instruments, for example when monitoring health-related quality of life in longitudinal studies and moving from paediatric to adult populations.
Having two versions of EQ-5D-Y available provides researchers with a wider choice of tools, allowing them to select the version which best meets their study needs and which is best adapted to local conditions.
To undertake a utility analysis, you will need to use a value set. Generally speaking, utility analysis requires a value set based on preferences from a general population. The rationale behind this is that the values are supposed to reflect the preferences of local taxpayers and potential receivers of healthcare. The EQ-5D value sets are therefore based on the values of the general population.
EQ-5D is used by scientists across the world in different settings and for many different diseases. It is used by academia (e.g. universities, research institutes), governments (national, regional, municipal), industry (e.g. pharmaceuticals, medical devices) and by hospitals and clinics (e.g. hospitals, GP practices). At an international level, the pharmaceutical industry and scientific groups are the foremost users of the instrument. EQ-5D is frequently used in (multinational) clinical trials by pharmaceutical companies.
Please contact the EuroQol office.
Translation timelines are based on multiple factors (the language, availability of source files, dependencies on other projects etc.). However, given that language versions of EuroQol instruments are produced following a very rigorous translation process, we generally operate with a default timeline of 4/5 months for new language versions. Click here for delivery timelines.
A brief summary of the translation process is provided in the following video.
You can check on the EQ-5D registration page to see whether the language version you need is available. If not, you will be provided with a quote and timelines for producing the translation.
The self/complete version of EQ-5D-Y-5L is available in paper and digital format for several languages, with more in development. Other modes of administration (proxy and interviewer-administered versions) will be available for some of those country/language pairs, and more will be added on an on-going basis. Please check on the EuroQol website for the latest list of available language versions by mode of administration.
The time trade-off (TTO), visual analogue scale (VAS) and discrete choice experiment (DCE) value sets differ in the technique used to elicit the values for the models.
In the TTO task, respondents are asked to imagine they live in a certain suboptimal health state for 10 years and then to specify the amount of time they would be willing to give up to live in full health instead. For example, someone might consider that 8 years in full health is equivalent to 10 years in the suboptimal health state.
The VAS technique asks people to indicate where they think a health state should be positioned on a vertical thermometer-like scale ranging from best imaginable health to worst imaginable health.
The DCE asks people to choose between two (or more) health states of varying severity across the five EQ-5D health domains (e.g. which is better, state A [32233] or state B [32321]?).
There has been much discussion about the theoretical and empirical properties of these three methods, and whether it is justified to calculate QALYs using values based on these methods, although all three techniques have been used to calculate QALYs. Currently, EQ-5D-5L value sets which are developed using the EQ-VT platform are based either on a combination of TTO and DCE values, or on TTO values only.
Please note that this is a large subject area and the brief answer provided above includes minimal details. For further information, the reader is encouraged to review the literature.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g.EQ-5D-5L health state 21143 represents a patient who indicates slight problems on the mobility dimension, no problems on the self-care and usual activities dimensions, severe pain or discomfort and moderate problems on the anxiety/depression dimension. These health states can be converted into a single index value using one of the standard EQ-5D-5L value sets. These value sets reflect the preferences of the general population. In contrast, the EQ VAS scores are self-reported and are therefore not representative of the general population. The EQ VAS self-rating records the respondent’s own assessment of their health status. Furthermore, the EQ VAS scores are anchored on 100 = the best health you can imagine and 0 = the worst health you can imagine, whereas the value sets are anchored on 11111 = 1 (representing full health) and dead = 0 and can therefore be used in QALY calculations.
The responses to the five EQ-5D dimensions (i.e. an EQ-5D health state or profile) can be converted into a single number called an index value. The index value reflects how good or bad the health state is according to the preferences of the general population of a country/region. The collection of index values for all possible EQ-5D states is called a value set.
EQ-5D is the name of the instrument and is not an acronym. EQ-5D is the correct term to use in print or verbally.
The EQ-5D-Y-3L and EQ-5D-Y-5L include the same dimensions (Mobility, Looking after myself, Doing Usual Activities, Having Pain or Discomfort, Feeling Worried, Sad or Unhappy) but the EQ-5D-Y-5L has five response options (or levels of severity) per dimension compared to the EQ-5D-Y-3L’s three levels. The level structure of the EQ-5D-Y-5L and the adult EQ-5D-5L are quite similar, unlike the EQ-5D-Y-3L and EQ-5D-3L, where the differences in wording are greater. For comparisons between adult and paediatric populations it may therefore be preferable to use the EQ-5D-Y-5L and the EQ-5D-5L.
Deciding whether to use the EQ-5D-Y-3L or the EQ-5D-Y-5L in any given context depends on many factors, including a study’s characteristics and aims, and the study population. The EQ-5D-Y-3L may be more appropriate in some instances, for example in younger populations, those with low literacy, or where interviewer-administration is required, as it is likely somewhat easier to understand, and may be easier to follow in an interview setting. If increased sensitivity and reduced ceiling effects are a relevant consideration, then EQ-5D-Y-5L may be more appropriate. Likewise, in studies which follow respondents from childhood/adolescence to adulthood, or which mix adult and paediatric populations, it is probably preferable to use the EQ-5D-Y-5L in conjunction with the EQ-5D-5L (for adults) as it is likely to be easier to compare and, potentially, aggregate data between those two versions than between the EQ-5D-Y-3L and EQ-5D-3L, due to the greater differences in content between the latter two versions. In studies in which preference-weighted values (utilities) are needed, e.g. in economic analysis, it should be noted that value sets are only currently available for EQ-5D-Y-3L, though EQ-5D-Y-5L value sets will become available in the future.
The EuroQol Office team will determine if a license agreement needs to be drawn up and whether a license fee is applicable, in accordance with our EQ-5D User License Policy.
EQ-5D paper versions will be provided as a Word document. For electronic versions, an Excel sheet will be provided with the EQ-5D labels, together with a document describing the EQ-5D electronic representation standards. The EQ-5D Demo versions on the website were created fully in line with our standards, so you can check how EQ-5D should look like on your system.
The descriptive system section of the EQ-5D questionnaire produces a 5-digit health state profile that represents the level of reported problems on each of the five dimensions of health, e.g. EQ-5D-5L health state 11313 represents a patient who indicates moderate problems on the usual activities and anxiety/depression dimensions and no problems on the remaining dimensions. Please note that this is just a ‘shorthand’ way of describing an EQ-5D health state; the numbers are simply code for the level in each dimension and have no arithmetic properties whatsoever. Therefore, they should not, for example, be added to give an overall score.
When publishing results obtained with the EQ-5D-Y-5L, the following key reference can be used:
Kreimeier S, Åström M, Burström K, Egmar AC, Gusi N, Herdman M, Kind P, Perez MA, Greiner W. (2019). EQ-5D-Y-5L: developing a revised EQ-5D-Y with increased response categories. Quality of Life Research, 28, 1951-1961.
The psychometric properties of the EQ-5D-Y-5L have been published in 18 studies to date.1 Most of these studies have compared the performance of the EQ-5D-Y-5L to the EQ-5D-Y-3L. Noteworthy results include reduced ceiling effects, and evidence for improved construct validity and responsiveness on the EQ-5D-Y-5L compared to the EQ-5D-Y-3L in some populations and conditions. The EQ-5D-Y-5L performed similarly to the EQ-5D-Y-3L when assessing test-retest reliability, child-caregiver agreement and missing responses. Further publications detailing the psychometric performance of the EQ-5D-Y-5L are anticipated.
- Data on file (manuscript in development)
All EQ instruments, including the EQ-5D-Y-5L are copyrighted. Without the prior written consent of the EuroQol Office, it is not permitted to alter, amend, convert, translate, publish or make available in whatever way (digital, hard-copy etc.) the EQ-5D-Y-5L and related proprietary materials.
At present, value sets for the EQ-5D-Y-5L are not available. The use of adult EQ-5D-5L value sets to generate EQ-5D values for EQ-5D-Y-5L health states is not recommended. The EQ-5D-5L and EQ-5D-Y-5L descriptive systems differ somewhat and preferences for child health may differ from preferences for adult health, which means that a value set for the EQ-5D-5L may misrepresent values for the EQ-5D-Y-5L. We therefore do not recommend using an EQ-5D-5L value set to derive preference weights (utilities) for EQ-5D-Y-5L health states.
There are currently no published EQ-5D-Y-5L value sets. A protocol is currently being developed to generate EQ-5D-Y-5L value sets, and upon completion of that protocol, value sets for the Y-5L instrument will be commissioned.
It is currently recommended to use the self-complete EQ-5D-Y-5L in children aged 8-15 years, i.e. the children should complete the questionnaire themselves. In children aged 4-7 years, researchers should consider using the proxy version of EQ-5D-Y-5L (i.e. a version in which a parent or other caregiver provides a rating of the child’s health) or an interviewer-administered version (for a self-rating by the child) . Both of these modes of administration can also be used in older children if needed. These recommendations are therefore identical for the EQ-5D-Y-5L and EQ-5D-Y-3L. Nevertheless, we advise that consideration be given to the schooling system and literacy level of the study population when deciding which version of the instrument to use, and which mode of administration
A considerable number of studies have shown that the EQ-5D-Y-5L is a psychometrically sound instrument which performs at least as well as the EQ-5D-Y-3L, and sometimes better. It has been approved for use by the EuroQol Research Foundation after a long period of development and testing which is described in several publications. Of course, researchers should decide which of the two versions of EQ-5D-Y is the most appropriate for their study, based on their study requirements, study aims, and the study population. Researchers should bear in mind that value sets for economic evaluation are currently not available for the EQ-5D-Y-5L.
The respondent will complete the EQ-5D. EQ-5D is primarily a self-complete instrument.
An interviewer will read the EQ-5D questions to the respondent and enter their responses because the respondent is either unable to read or write or is unable to be physically present for the interview. May be used interchangeably with existing Telephone- and Face-to-face versions.
This is a legacy version, and in time Interviewer-administered versions will be replacing face-to-face versions. Face-to-face versions were developed for use when participants are able to be physically present during the interview, but are unable to read or write.
This is a legacy version, and in time Interviewer-administered versions will be replacing Telephone versions. Telephone versions were developed for use when participants are unable to be physically present during the interview, but have access to a telephone.
A caregiver (the proxy) who knows the respondent well will respond to the questionnaire by providing their own impression of the respondent’s health. This version should only be used if the respondent is unable to report on their own health for any reason.
A caregiver (the proxy) who knows the respondent well will rate how they think the respondent would rate their own health, if the respondent were able to communicate it. This version should only be selected if the respondent is unable to report on their own health for any reason.
An interviewer will enter the responses of a caregiver (the proxy) who knows the respondent well. The caregiver will respond to the questionnaire by providing their own impression of the respondent’s health. This version should only be selected for respondents who are unable to report on their own health for any reason.
An interviewer will enter the responses of a caregiver who knows the respondent well. The caregiver will rate how they think the respondent would rate their own health, if the respondent were able to communicate it. This version should only be selected for respondents who are unable to report on their own health for any reason.
Please contact the EuroQol Office for the release notes from the update. These describe the changes and the reasons for them.
Minor and major changes, when they occur, will be published immediately.
New products are released as soon as they are available for use.
A list of all products and their version number is available on our website. If you have any additional questions, please contact the EuroQol Office.
All translations/adaptations of EQ-5D are produced using a standardized translation protocol that conforms to internationally recognized guidelines. These guidelines aim to ensure equivalence to the English ‘source’ version and involve a forward/backward translation process and cognitive debriefing. No translation can receive official endorsement from the EuroQol Research Foundation, unless it has been performed in strict adherence according to the EuroQol Research Foundation’s translation guidelines. The agencies we work with are compliant with our requirements.
No, your current study is not affected. The content of our products has not changed. You can use the existing EQ-5D products with confidence.
Translation certificates for Paper Self-Complete versions are applicable for all corresponding modes of administration and can be provided upon request. Translation certificates only confirm and reflect the most extensive translation procedure and will not be revised if minor or major modifications are made as the underlying translation procedure is unchanged.
There are over 30 country specific value sets for the EQ-5D-3L and more than 20 country specific value sets for the EQ-5D-5L. While we aim to produce value sets for many more countries, it is not rare that users need a value set that is not yet available. If you need to obtain health state utility values for the EQ-5D-3L, it is recommended to use the United Kingdom value set from Dolan et al. (2002). If you need to obtain health state utility values for the EQ-5D-5L, the recommendation is to use the United States EQ-5D-5L value set from Pickard et al. (2019) as the United Kingdom valuation study is currently ongoing.
If both TTO and VAS tariffs are available for your country, it would be recommended to use TTO tariffs. This is because, contrary to VAS, TTO is a choice-based preference elicitation method. This method is the preferred elicitation procedure according to the EQ-VT protocol.
The EuroQol Office team will determine if a license agreement needs to be drawn up and whether a license fee is applicable, in accordance with our EQ-5D User License Policy.
EQ-5D paper versions will be provided as a Word document. For electronic versions, an Excel sheet will be provided with the EQ-5D labels, together with a document describing the EQ-5D electronic representation standards. The EQ-5D Demo versions on the website were created fully in line with our standards, so you can check how EQ-5D should look like on your system.
Yes, the EQ-5D is subject to copyright protection. Anyone interested in using the instrument should first register with EuroQol, as you can only obtain EQ-5D by completing the EQ-5D Registration Form. We can then provide you with the requested EQ-5D versions, languages and modes of administration you require. Please note, you are not obliged to purchase the EQ-5D by registering.
If you have already seen the EQ-5D-5L and/or have decided to go ahead and use it, please register your study/project/trial first, by completing the EQ-5D registration form. The EuroQol Office will then contact you by e-mail and inform you about the terms and conditions which apply if you decide to use the EQ-5D, including licensing fees (if applicable). Please allow approximately 5 working days to receive this reply.
EuroQol does not charge a license fee for non-commercial uses of EQ-5D. After registering to use the instrument, EQ-5D can be used free of charge for academic, educational, public health, and other non-commercial purposes. A small fee may be charged for screen shot review if data is collected digitally on a platform other than REDCAP®, LIMESURVEY®, QUALTRICS® or CASTOR EDC®.
Licensing fees are determined by the EuroQol Office based on the user information provided in the registration form. If applicable, the size of the license fee depends on the type of study, funding source, sample size and number of requested EQ-5D versions and languages. You are not obliged to purchase the EQ-5D by registering. Click here for the EQ-5D user license policy.
Licensee and it’s assisting Vendor will be responsible for creating correct digital Representations, based on the documents provided by EuroQol. The EuroQol Office team will no longer be involved in the screenshot review of all reproductions. However, the team is available if required to help with screenshot review or digital Representation issues. As a service to commercial customers, the EuroQol Office team will request to see EQ-5D implementations selected at random, as a quality check. Feedback will then be provided to customers, and vendors if applicable, on the Representation quality. The main rule is that every deviation from the Representation Design Guidelines, or from the provided Representations, is at the risk of the Licensee/Vendor.
Licensing fees are determined on the basis of the information provided on the registration form. The applicable User Policy is dependent on the type of study/trial/project, funding source, sample size and number of requested languages. Please be advised that by registering, you are not obligated to purchase a license. Note: EuroQol does not charge a license fee for non-commercial use of EQ-5D. After registering to use the instrument, EQ-5D can be used free of charge for academic, educational, public health, and other non-commercial purposes.
Yes. Please note that without the prior written consent of the EuroQol Office, you are not permitted to use, reproduce, alter, amend, convert, translate, publish or make available in whatever way (digital, hard-copy etc.) the EQ-5D and related proprietary materials.
The EuroQol Research Foundation stresses that any and all copyrights in the EQ-5D, its (digital) representations, and its translations are exclusively vested in the EuroQol Research Foundation. EQ-5D™ is a trade mark of the EuroQol Research Foundation.
No, without the prior written consent of the EuroQol Office, you are not permitted to use, reproduce, alter, amend, convert, translate, publish or make available in whatever way (digital, hard-copy etc.) the EQ-5D and related proprietary materials. Please contact the EuroQol Office if you would like to reproduce EQ-5D.
EuroQol will not be able to offer paid screenshot review services for the new digital format. Please be advised that there are commercial parties offering review services, such as translation agencies and EPRO vendors with experience with the EQ-5D. Please contact these parties directly if you are interested in these services.
Please be advised that after 6 April 2022, we will only provide new license agreements for using the new digital format, with the new license fee structure. Amendments to add languages to device-dependent license agreements will no longer be possible, because the use of device-dependent versions will be phased out.
Licensee and Vendor will be responsible for creating correct digital Representations, based on the documents provided by EuroQol. The EuroQol Office team will no longer be involved in the screenshot review of all reproductions. However, the team is available if required to help with screenshot review or digital Representation issues.
As a service to commercial customers, the EuroQol Office team will request to see EQ-5D implementations selected at random, as a quality check. Feedback will then be provided to customers, and vendors if applicable, on the Representation quality. The main rule is that every deviation from the Representation Design Guidelines, or from the provided Representations, is at the risk of the Licensee/Vendor.
Non-commercial customers who want to collect data on an unsupported digital platform will be required to download, sign and upload a “Digital Use Letter” via the EuroQol Customer Portal, after registration. The Digital Use Letter provides customers with basic guidance on how to create a correct Representation of EQ-5D on their digital platform. This is of vital importance, as an incorrect Representation of EQ-5D could invalidate the collected data.
Yes, active device-dependent license agreements will include the right to use the new digital format. However, license agreement amendments to add languages to device-dependent license agreements will not be possible, as the device-dependent license agreements will be phased out. To add languages, a new license agreement will be drawn up.
Yes, in ongoing studies the device-dependent versions can continue to be used. These will become “legacy” versions, which will not be updated in the future and will gradually be phased out.
If new languages are added to an ongoing study, these will be provided in the new digital format, as these are the most up-to-date versions. If for ongoing studies you would also like to receive the device-dependent language versions for consistency reasons, please inform your EuroQol contact person. However, please note that the use of these legacy device-dependent versions will be at your own risk, as legacy versions will no longer be maintained or updated.