Understanding health state valuations: a qualitative analysis of respondents' comments

Exploring potential EQ-5D bolt-on dimensions with a qualitative approach: an interview study in Hong Kong SAR, China

PURPOSE

The introduction of bolt-on dimensions in EQ-5D instruments is growing common, but most bolt-on studies have targeted the diseased population and obtained bolt-on from other existing Health-related Quality of Life (HRQoL) instruments. As the qualitative approach offers important evidence to support the consistency and design of the potential bolt-on items, this paper studies the Hong Kong SAR community's perception of the current EQ-5D-5 L instrument and identifies potential bolt-on via a qualitative approach.

METHODS

A representative sample mix was recruited based on the age group, gender, and education level composition of the Hong Kong SAR community by quota sampling. Semi-structured interviews were conducted and the interviews were transcribed and coded to identify emergent and recurrent themes.

RESULTS

Thirty interviews were conducted and the majority of the interviewees considered the EQ-5D-5 L insufficiently comprehensive to illustrate their HRQoL. While some key HRQoL aspects included in the EQ-5D matched with the community's HRQoL perception, respondents showed concern about the potential overlap of the existing HRQoL dimension, the optimal number or attributes, and the appropriateness of the EQ-VAS. Among the potential bolt-on dimensions that emerged, 'Sleep', 'Interpersonal Relationship', and 'Satisfaction' were the key potential bolt-on dimensions identified and emphasized in the interviews.

CONCLUSIONS

The qualitative findings of the study illustrate the possible gap between EQ-5D-5 L measurements and community HRQoL perception, while the findings support the development of EQ-5D bolt-on dimensions in the target community with content and face validity.

How Well Does the EQ-5D-Y-5L Describe Children With Intellectual Disability?: "There's a Lot More to My Child Than That She Can't Wash or Dress Herself."

OBJECTIVES

The EQ-5D-5L is a generic health utility instrument for measuring health-related quality of life (HRQoL), with self-report and proxy report versions for children (EQ-5D-Y-5L). Children with intellectual disability (ID) are a heterogeneous population whose impairments and comorbidities place them at risk of poor HRQoL. This study aimed to describe the content validity and suitability for children with ID of a proxy report version of the EQ-5D-Y-5L as seen by their caregivers.

METHODS

A proxy report EQ-5D-Y-5L was administered to caregivers of children with ID. Using cognitive think-aloud interviewing, participants were encouraged to provide the reasoning for their choices, assess the questions' relevance, comprehensibility, and comprehensiveness, and comment on the tool's strengths and weaknesses. Qualitative content analysis used both directed (deductive) and conventional (inductive) methods.

RESULTS

There were 28 interviews with 30 caregivers of children with ID (aged 8-22 years, 17 boys, with autism spectrum disorder, cerebral palsy, Down syndrome, and rare genetic disorders). The EQ-5D-Y-5L was considered clear, concise, and largely relevant, but insufficiently comprehensive for this population. Interviewees sought clarification of the definition of HRQoL, whether it included unchanging impairments (vs fluctuating health states), and what basis of comparison to use (child or peer). Many interviewees suggested inclusion of questions for other domains, including communication and social engagement, equipment and human supports required, and a wider range of mental health questions.

CONCLUSIONS

The study suggests that further work is required to ensure accurate responses to the EQ-5D-Y-5L from caregivers of children with ID and to describe these children adequately.

Conceptual Framework for Optimised Proxy Value Set Selection Through Supra-National Value Set Development for the EQ-5D Instruments

BACKGROUND

Preference differences between countries and populations justify the use of country-specific value sets for the EQ-5D instruments. There are no clear criteria based on which the selection of value sets for countries without a national value set should be made. As part of the European PECUNIA project, this study aimed to identify factors contributing to differences in preference-based valuations and develop supra-national value sets for homogenous country clusters in Europe.

METHODS

A literature review was conducted to identify factors relevant to variations in the EQ-5D-3L/5L health state valuations across countries. Factors fulfilling the pre-specified criteria of validity, reliability, international feasibility and comparability were used to group 27 European Union member states, the European Free Trade Association countries and the UK. Clusters of countries were developed based on the frequency of their appearance in the same grouping. The supra-national value sets were estimated for these clusters from the coefficients of existing published valuation studies using the ordinary least-squares model.

RESULTS

Ten factors were identified from 69 studies. From these, five grouping variables: (1) culture and religion; (2) linguistics; (3) healthcare system typology; (4) healthcare system financing; and (5) sociodemographic aspects were derived to define the groups of homogenous countries. Frequency-based grouping revealed five cohesive clusters: English-speaking, Nordic, Central-Western, Southern and Eastern European.

CONCLUSIONS

European countries were clustered considering variables that may relate to differences in health state valuations. Supra-national value sets provide optimised proxy value set selection in the lack of a national value set and/or for regional decision making.

Meaningful values of the EQ-5D-3L in patients undergoing primary knee arthroplasty

AIMS

The aim of this study was to report the meaningful values of the EuroQol five-dimension three-level questionnaire (EQ-5D-3L) and EuroQol visual analogue scale (EQ-VAS) in patients undergoing primary knee arthroplasty (KA).

METHODS

This is a retrospective study of patients undergoing primary KA for osteoarthritis in a university teaching hospital (Royal Infirmary of Edinburgh) (1 January 2013 to 31 December 2019). Pre- and postoperative (one-year) data were prospectively collected for 3,181 patients (median age 69.9 years (interquartile range (IQR) 64.2 to 76.1); females, n = 1,745 (54.9%); median BMI 30.1 kg/m² (IQR 26.6 to 34.2)). The reliability of the EQ-5D-3L was measured using Cronbach's alpha. Responsiveness was determined by calculating the anchor-based minimal clinically important difference (MCID), the minimal important change (MIC) (cohort and individual), the patient-acceptable symptom state (PASS) predictive of satisfaction, and the minimal detectable change at 90% confidence intervals (MDC-90).

RESULTS

The EQ-5D-3L demonstrated good internal consistency with an overall Cronbach alpha of 0.75 (preoperative) and 0.88 (postoperative), respectively. The MCID for the Index score was 0.085 (95% confidence interval (CI) 0.042 to 0.127) and EQ-VAS was 6.41 (95% CI 3.497 to 9.323). The MIC_COHORT was 0.289 for the EQ-5D and 5.27 for the EQ-VAS. However, the MIC_INDIVIDUAL for both the EQ-5D-3L Index (0.105) and EQ-VAS (-1) demonstrated poor-to-acceptable reliability. The MDC-90 was 0.023 for the EQ-5D-3L Index and 1.0 for the EQ-VAS. The PASS for the postoperative EQ-5D-3L Index and EQ-VAS scores predictive of patient satisfaction were 0.708 and 77.0, respectively.

CONCLUSION

The meaningful values of the EQ-5D-3L Index and EQ-VAS scores can be used to measure clinically relevant changes in health-related quality of life in patients undergoing primary KA.Cite this article: Bone Joint Res 2022;11(9):619-628.

'Like holding the axe on who should live or not': adolescents' and adults' perceptions of valuing children's health states using a standardised valuation protocol for the EQ-5D-Y-3L

Purpose

There is an increasing interest for using qualitative methods to investigate peoples’ cognitive process when asked to value health states. A standardised valuation protocol for the EQ-5D-Y-3L instrument was recently developed. Little is known regarding how people think, reason, and feel when asked to value health states for children. The aim was to explore how adolescents and adults perceive the task of valuing children’s health states using the standardised valuation protocol.

Methods

This was a qualitative study where adults (n = 10) and adolescents (n = 10) from the general population participated in individual video-interviews. Initially, participants reported their own health with the EQ-5D-3L instrument. Then they were asked to complete several valuations tasks for a 10-year-old child according to the standardised valuation protocol, followed by a semi-structured interview with open-ended questions to further explore participants’ perceptions. A qualitative content analysis was performed.

Results

The two main categories that emerged from the data were ‘Thoughts and feelings when valuing children’s health states’ and ‘Strategies when valuing children’s health states’. Participants expressed feeling doubt, awfulness and being reluctant to trade-off life years, and questioned who has the right to value health states for children. Experience and point of view were strategies participants used to complete the valuation tasks.

Conclusion

The findings from the present study can contribute to the understanding and interpretation of quantitative results where the standardised valuation protocol has been used to derive values for the EQ-5D-Y-3L. Furthermore, results of the study support the feasibility of including adolescents in valuation studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11136-022-03107-0.

Adding a fatigue item to the EQ-5D-5L improves its psychometric performance in the general population

Background

Fatigue is a common and often disturbing sequela of serious chronic health conditions. In the widely applied HRQL instrument, the EQ-5D, this aspect is not included directly, for its assumed lack of additional information. We investigated the validity of this assumption by determining the gain—if any—of an additional fatigue item to the EQ-5D-5L in a general population sample.

Methods

A Dutch general population sample (including diseased people) completed a web-based survey including the EQ-5D-5L and the Rivermead Post-Concussion Symptoms Questionnaire (RPQ). The RPQ fatigue item was used to create the EQ-5D-5L + Fatigue. We head-to-head compared the psychometric performance contrasting the EQ-5D-5L and EQ-5D-5L + Fatigue: distribution (e.g. ceiling), informativity cf. Shannon's indices, convergent validity, domain dependency, and explanatory power. Results were compared between subgroups with and without ≥ 1 chronic health condition.

Results

The study population consisted of 3027 persons of whom 52% had a chronic health condition. The mean EQ-5D-5L utility score was 0.83 and 48% experienced some degree of fatigue. Adding the fatigue item to the EQ-5D-5L decreased the ceiling effect, increased absolute informativity (Hʹ = 6.44 vs. Hʹ = 4.90) and relative informativity (Jʹ = 0.46 vs. Jʹ = 0.42). The extra fatigue item slightly increased convergent validity (Spearman’s rank correlation coefficient = − 0.61 vs. − 0.62). Domain dependency analysis showed that all EQ-5D-5L domains are dominant over the fatigue item. Explanatory power of the EQ-5D-5L + Fatigue was higher compared to the EQ-5D-5L (R² = 0.42 vs. 0.39). The gain is substantially larger in the subgroup with chronic health conditions.

Conclusions

Adding a fatigue item to the EQ-5D-5L improved all psychometric performance criteria of the enriched instrument in the general population. Effects are substantially larger in the subgroup with chronic health conditions, indicating that adding a fatigue item to the EQ-5D-5L is especially relevant in evaluating the HRQL of diseased people.

A Review of Unsolicited Comments on the CAHPS 5.0 Health Plan Survey

The CAHPS Health Plan Survey (CAHPS 5.0) collects invaluable information regarding consumer experiences with their health plans, and these data inform healthcare policies at both the state and federal levels. The purpose of this paper was to explore unsolicited comments provided on the CAHPS 5.0 survey of one state's Medicaid program. Secondary data analysis was conducted of unsolicited, written comments received from Medicaid recipients who completed the CAHPS 5.0 adult or child postal survey between 2016 and 2018. The majority of unsolicited comments were moderately or very negative in attitude (or tone) for adult and child surveys. Analysis of unsolicited comments yielded 3 themes: positive experiences with Medicaid, limitations of coverage, and direct requests for assistance. Providing space for Medicaid patients to share comments and receiving further guidance for content analysis would provide valuable context for interpreting overall survey results. Comments may also help Medicaid program administrators respond to the frequently complex and challenging experiences of navigating a continually evolving state health insurance program by the most vulnerable populations.

The relation between EQ-5D and fatigue in a Dutch general population sample: an explorative study

Background

Fatigue negatively influences health-related quality of life. It is questionable whether fatigue is sufficiently covered by the EQ-5D. This study investigated whether fatigue is covered by the existing domains of the EQ-5D.

Methods

A Dutch general population sample completed the EQ-5D (3L and 5L version) and the Rivermead Post-Concussion Symptoms Questionnaire (RPQ), of which the fatigue item was used. Outcomes were compared between participants with and without a chronic health condition. Convergent validity was assessed, and multivariate regression analyses was used to predict the RPQ fatigue item from the EQ-5D-3L and EQ-5D-5L domains separately.

Results

3027 people completed the survey, of whom 52% had ≥ 1 chronic health condition. Fatigue was reported by 48% of the participants. Fatigue was moderately correlated to the EQ-5D domains ‘pain/discomfort’, ‘usual activities’, and ‘anxiety/depression’ for the 3L (r = 0.379–0.426) and 5L version (r = 0.411–0.469). For the 5L, also a moderate correlation with ‘mobility’ (r = 0.335) was observed. The remaining correlations were weak. All EQ-5D-3L and 5L domains except for ‘mobility’ were significantly associated with the RPQ fatigue item (unstandardized Beta = − 0.20–0.67; p < 0.01 to p = 0.04). Comparable outcomes were found for participants with and without ≥ 1 chronic health condition.

Conclusions

The extent to which fatigue is covered by the EQ-5D domains is small to moderate, with the EQ-5D-5L being slightly more sensitive to capture fatigue compared to the EQ-5D-3L. An extra fatigue item for the EQ-5D may add value, as fatigue is not fully captured by the existing domains, both in people with and without a chronic health condition.

Acceptability of the health-related quality of life instrument EQ-5D-Y-5L among patients in child and adolescent psychiatric inpatient care

Aim

The generic EuroQol 5 Dimensions Youth 5 Level (EQ‐5D‐Y‐5L) measures health‐related quality of life among children from 8 years. Respondents report their health on five dimensions with five severity levels and rate their overall health on a visual analogue scale (EQ VAS). The aim of the study was to explore acceptability of the EQ‐5D‐Y‐5L instrument among patients in child and adolescent psychiatric inpatient care.

Methods

A convenience sample of patients within a psychiatric inpatient care clinic in Region Stockholm, Sweden, was used. Follow‐up questions were answered directly after filling in the EQ‐5D‐Y‐5L. Conventional qualitative content analysis was chosen to analyse the open‐ended questions on how they perceived answering the instrument.

Results

In total, 52 patients (83% girls), mean age 15.4 years (range 13‐17), were included. Three themes emerged: generic content of the EQ‐5D‐Y‐5L descriptive system; design and wording of the EQ‐5D‐Y‐5L descriptive system and the EQ VAS; self‐reporting health with the EQ‐5D‐Y‐5L descriptive system and the EQ VAS.

Conclusion

The inclusion of physical health dimensions was perceived as positive, but some patients considered the descriptive system too generic. The results indicate that these patients in general could self‐report their health in a meaningful way with the EQ‐5D‐Y‐5L instrument.

Reporting and valuing one's own health: a think aloud study using EQ-5D-5L, EQ VAS and a time trade-off question among patients with a chronic condition

Background

The EQ-5D-5L, the EQ VAS, and the time trade-off (TTO) are commonly used to report and value health. Still, there is a need to better understand how these questionnaires and methods are perceived by the respondents, as well as the thoughts and motives behind their responses. The aim of this study was to increase knowledge of how individuals think and reason when reporting and valuing their own current health, using EQ-5D-5L, EQ VAS, and an open-ended TTO question.

Methods

Twenty patients with type 1 diabetes participated in qualitative individual think aloud interviews in Stockholm, Sweden. Participants were asked to describe their thoughts when responding to three assessments. The interviews were transcribed verbatim and analyzed using thematic analysis.

Results

The analysis showed that participants conducted the assessments by contextualizing and interpreting instructions, relating the questions to their own health, using different recall periods and time perspectives, and using personal, interpersonal, or normative comparators. It was challenging to reduce the experience of everyday life into a response option, and the thoughts behind the responses differed between the assessments. Before deciding on what to include, participants thought of the purpose and context of the assessments. Current health or past experiences of health were applied in the EQ-5D descriptive system and in EQ VAS, while participants focused on the future in the TTO. Thoughts about the impact on others, personal goals, and expectations on future health were more clearly integrated in the TTO assessment. All participants considered the trade-off between life years and health. However, despite the use of different comparators, the concept of ‘full health’ was found difficult to imagine or relate to.

Conclusions

This study provides insights as to how responses to the EQ-5D-5L, EQ VAS, and TTO assessments are complementary and where these assessments differ in adults with a chronic condition. The findings may contribute to a better understanding when interpreting the quantitative results and contribute to the literature pertaining to possible explanations for differences in health state values depending on the valuation method.

Incorporating Mortality in Health Utility Measures

The creation of multiattribute health utility systems requires design choices that have profound effects on the utility model, many of which have been documented and studied in the literature. Here we describe one design choice that has, to the best of our knowledge, been unrecognized and therefore ignored. It can emerge in any multiattribute decision analysis in which one or more essential outcomes cannot be described in terms of the multiattribute space. In health applications, the state of being dead is such an outcome. When the remaining health is conceptualized as a multidimensional space, determining the utility of the state of being dead requires using the interval-scale properties of cardinal utility, combined with elicited utilities for the state of being dead and the all-worst state, to produce a utility function in which the state of being dead has a utility of 0 and full health has a utility of 1 (i.e., the quality-adjusted life-year scale). Although previously unrecognized, there are two approaches to accomplish that step, and they produce different results in almost all cases. As a corollary, the choice of approach determines the proportion of states rated as worse than dead by the system. For example, in the Health Utility Index 3 (HUI3), the method used classifies 78% of the 972,000 unique health states in the classification system as worse than dead, and that proportion increases to 85% when the HUI3 is recalculated using the alternative approach. Studies of populations with significant morbidity are the most likely to be sensitive to the design choice. Those who design utility measures should be aware that they are using a researcher degree of freedom when they decide how to scale the state of being dead.

Validity of an enhanced EQ-5D-5L measure with an added cognitive dimension in patients with stroke

Objective:

The 5-level EuroQoL (EQ-5D-5L) is a patient-reported outcome measure frequently used in stroke research. However, it does not assess the cognitive problems many patients with stroke experience. The aim of this article is to compare the content validity, internal consistency and discriminative ability of the EQ-5D-5L with and without an additional cognitive domain (EQ-5D-5L+C), administered three months post-stroke.

Design:

Cross-sectional study.

Setting:

Six general hospitals in the Netherlands.

Subjects:

In all, 360 individuals with stroke three months after the event.

Interventions:

Not applicable.

Main measures:

The modified Rankin Scale and EQ-5D-5L+C were administered in telephone interviews three months post-stroke.

Results:

A total of 360 patients with stroke were included. Mean age was 68.8 years (standard deviation (SD) = 11.7), 143 (40%) were female, 334 (93%) had had an ischemic stroke, 165 (46%) had a National Institutes of Health Stroke Scale (NIHSS) score ⩽ 4 at presentation and the Barthel Index was 17.2 (SD = 4) four days post-stroke. Cognitive problems were reported by 199 (55%) patients three months post-stroke. Internal consistencies of the EQ-5D-5L and EQ-5D-5L+C were 0.75 and 0.77, respectively. Adding a cognitive domain resulted in a decrease of the ceiling effect from 22% to 14%. Both EQ-5D-5L and EQ-5D-5L+C showed good discriminative ability, but differences between patients with different modified Rankin Scale scores and with/without reported decrease in health and daily activities were slightly larger with the EQ-5D-5L+C compared to the EQ-5D-5L.

Conclusions:

The EQ-5D-5L+C, which includes a cognitive domain that is highly significant for stroke patients, showed increased content validity and good discriminative ability, without losing internal consistency.

Describing the Development of a Health State Valuation Protocol to Obtain Community-Derived Disability Weights

For the prioritization of the allocation of national resources, estimating the burden of disease studies play a critical role. Hence the first Global Burden of Disease study conducted in the 1990s was done for this particular estimation. By the means of introducing disability-adjusted life year (DALY) metric, the burden of various diseases was calculated using disability weights (DWs)—a component of DALY. DWs are values that capture individuals' perception regarding the severity of diseases that involve valuation tools and health state descriptions. Various studies have been conducted over the past few decades to evaluate health states and derive disease-specific disability weights using Person-Trade off, Time-trade off, etc. However, use of these complex and cognitively demanding methods has been carried out in developed countries where the bulk of the populace is more educated. Few attempts have been made in low- and middle-income countries such as India, where not only the majority is less educated but also the social construction of diseases and health conditions are diverse. Therefore, due to the absence of methodological protocols of health state valuations for application at the community-level in the developing world, we attempted to systematically describe the procedure that can be used universally and cross-culturally for various health states. We began with the tentative selection of health states and health states valuation methods by conducting a meticulous literature review, followed by community exploration and medical consultations. This led to developing vignettes (clinical description) and 6D5L pictorial narrations (functional status description). Two field tests for checking the usability and refinement of the tools was done. Final consultation by an expert panel comprising of medical and non-medical professionals was held/conducted to finalize the health state labels and functional status profiles of each health state. The methodical approach provides a robust and thorough procedure for guiding researchers to implement health state valuation studies at community level.

Exclusion Criteria as Measurements I: Identifying Invalid Responses

Background. In a systematic review, Engel et al. found large variation in the exclusion criteria used to remove responses held not to represent genuine preferences in health state valuation studies. We offer an empirical approach to characterizing the similarities and differences among such criteria. Setting. Our analyses use data from an online survey that elicited preferences for health states defined by domains from the Patient-Reported Outcomes Measurement Information System (PROMIS^®), with a U.S. nationally representative sample (N = 1164). Methods. We use multidimensional scaling to investigate how 10 commonly used exclusion criteria classify participants and their responses. Results. We find that the effects of exclusion criteria do not always match the reasons advanced for applying them. For example, excluding very high and very low values has been justified as removing aberrant responses. However, people who give very high and very low values prove to be systematically different in ways suggesting that such responses may reflect different processes. Conclusions. Exclusion criteria intended to remove low-quality responses from health state valuation studies may actually remove deliberate but unusual ones. A companion article examines the effects of the exclusion criteria on societal utility estimates.

How Prevalent Are Implausible EQ-5D-5L Health States and How Do They Affect Valuation? A Study Combining Quantitative and Qualitative Evidence

BACKGROUND

When designing a valuation study, a criterion that has been used for selecting health states for direct valuation is whether the health states are plausible for respondents, because it is assumed that inclusion of implausible states would compromise data quality.

OBJECTIVES

To understand which health states are implausible, and how their values differ from the values of the plausible counterparts.

METHODS

One thousand six hundred Chinese students valued all 3125 health states of the 5-level EuroQol 5-dimensional questionnaire (EQ-5D-5L) using the EuroQol visual analogue scale. Of these, 890 students also indicated whether each valued state was implausible or not using a binary scale. Additional qualitative interviews were conducted concerning the thought processes involved in the valuation of implausible states. We calculated an implausible score for each state. Then we examined the effect of implausibility on visual analogue scale values by fitting 2 regression models. Two independent researchers analyzed the qualitative transcripts using thematic analysis.

RESULTS

Approximately 30% of the EQ-5D-5L health states were rated as implausible by at least 50% of the respondents, but there was substantial heterogeneity in views about the plausibility of EQ-5D-5L states. Health states with dimensions that conflicted were more likely to be judged as implausible states. Health states that respondents deemed as implausible were more difficult to value and had lower values.

CONCLUSIONS

When respondents found the EQ-5D states to be implausible, they tended to give them lower values. Nevertheless, completely excluding implausible states from a valuation study is not possible because there is a lack of agreement among respondents on which states are implausible.

Do time trade-off values fully capture attitudes that are relevant to health-related choices?

Previous research has shown that demographics, beliefs, and self-reported own health influence TTO values. Our hypothesis is that attitudes towards length and quality of life influence TTO values, but should no longer affect a set of related choices that are based on respondents' own TTO scores. A representative sample of 1339 respondents was asked their level of agreement to four statements relating to the importance of quality and length of life. Respondents then went on to value 4 EQ-5D 5L states using an online interactive survey and a related set of 6 pairwise health-related choice questions, set up, so that respondents should be indifferent between choice options. We explored the impact of attitudes using regression analysis for TTO values and a logit model for choices. TTO values were correlated with the attitudes and were found to have a residual impact on the choices. In particular, those respondents who preferred quality of life over length of life gave less weight to the differences in years and more weight to differences in quality of life in these choice. We conclude that although the TTO responses reflect attitudes, these attitudes continue to affect health-related choices.

Selecting Bolt-On Dimensions for the EQ-5D: Examining Their Contribution to Health-Related Quality of Life

BACKGROUND

Generic preference-based measures may miss dimensions important for the health-related quality of life (HRQOL) of patients. When this happens, a possible solution is to add bolt-ons. Finch et al. (Finch AP, Brazier JE, Mukuria C, Bjorner JB. An exploratory study on using principal component analysis and confirmatory factor analysis to identify bolt-on dimensions: the EQ-5D case study. Value Health 2017;10:1362-75) have recently shown that bolt-ons can be systematically identified using factor analysis. Nevertheless, because for each bolt-on option a complete re-evaluation may be required, methods to select between them are needed.

OBJECTIVES

To investigate the possibility of selecting bolt-ons using their ability to predict differences in HRQOL. It tests six factors (energy/vitality, satisfaction, relationships, hearing, vision, and speech), and 37 items loading on them, using the EuroQol five-dimensional questionnaire as a case study.

METHODS

Data were obtained from the Multi-Instrument Comparison study, an online survey on health and well-being measures carried out in six countries. Two tests were performed. In the first test, linear regressions were fitted to determine whether different bolt-ons helped explain variations in HRQOL as measured by the Health visual analogue scale. The upper anchor (100) of this scale represents excellent physical, mental, and social health, and the lower anchor (0) represents death. Bolt-on relevance was judged comparing the strength, direction, and statistical significance of unadjusted β coefficients. In the second test, linear regressions were fitted to further investigate whether different factors and items helped explain the negative effect of six chronic conditions on HRQOL. A reduction in the coefficients for the chronic condition dummies meant that the factor or item detected the effect.

RESULTS

Energy/vitality, relationships, and satisfaction reported substantially larger coefficients than did speech, vision, and hearing. Also, items loading on energy/vitality, relationships, and satisfaction generally presented larger coefficients than did those loading on speech, vision, and hearing. The second test did not detect consistent decrements in the coefficients for chronic conditions when testing factors, but it generally did detect consistent decrements when testing items.

CONCLUSIONS

The first test appeared useful for bolt-on selection. Further research is needed before using the second test.

What were they thinking when providing preference measurements for generic health states? The evidence for HUI3

Background

Multi-attribute generic preference-based measures of health-related quality of life are used as comprehensive outcome measures. Typically preferences for health states defined by these systems are elicited from a representative sample of the general population. An important element in that elicitation process is the information that respondents were instructed to consider in providing their responses.

Methods

A random sample of community-dwelling respondents in Canada was surveyed in face-to-face interviews. Respondents provided preference scores for selected Health Utilities Index Mark 3 (HUI3) health states. Respondents also answered questions about the most important attributes and the importance of various impacts of the health states in providing their preference scores.

Results

Fifty per cent of respondents reported that they focussed on two, and 21% on three, attributes of the eight HUI3 attributes. Each of the eight attributes was identified as important; pain (49%), vision (37%), cognition (34%), emotion (28%), and ambulation (28%) were the most important. The null hypothesis that all of the attributes were equally important was rejected (p < 0.001). With respect to the impacts, 89% of respondents indicated that the ability to take care of oneself was quite or very important; similarly 76% reported the same for impact on family life, 69% for impact on the happiness of others, 61% for the impact on their ability to work, and 42% for the impact on their leisure activities. The null hypothesis that all of the impacts were equally important was rejected (p < 0.001).

Conclusions

In providing preference scores for HUI3 health states, respondents thoughtfully examined the implications of the health states for their ability to live, work, socialize, and function.

Valuation of depression co-occurring with a somatic condition: feasibility of the time trade-off task

BACKGROUND

Health state valuations obtained from the general population are used for cost-utility analyses of health-care interventions. Currently, most studies have focused on valuations of somatic conditions, to a much lesser extent of mental states, that is, depression and even less on valuations of depression co-occurring with somatic conditions.

OBJECTIVE

We tested the feasibility of the time trade-off (TTO) task to elicit valuations for depression solitary or co-occurring with a somatic condition. Moreover, we explored person- and state-related factors that may affect valuations.

DESIGN

During semi-structured interviews, 10 individuals (five women, mean age: 36 years) used a TTO task to value vignettes describing mild and severe depression; and mild depression co-occurring with moderate and severe states of cancer, diabetes or heart disease. During valuations, participants were thinking aloud. Feasibility criteria were successful completion and difficulty/concentration (1-10); logical consistency of values; and comprehension of the TTO, based on qualitative analysis of think aloud data. Factors influencing valuations were generated from think aloud data.

RESULTS

Participants reported satisfactory levels of difficulty (mean: 1.9) and concentration (mean: 8.3) and assigned consistent values. Qualitative analysis revealed difficulties with imagining: living with depression for lifetime (n = 4); reaching the age of 80 (n = 6); and living with a somatic condition and mentally healthy (n = 6). Person- and state-related factors, for example perceived susceptibility to depression (n = 4), appeared to affect valuations.

CONCLUSION

Quantitative findings supported feasibility of the valuation protocol, yet qualitative findings indicated that certain task aspects should be readdressed. Factors influencing valuations can be explored to better understand valuations.

Logical Inconsistencies in 3 Preference Elicitation Methods for EQ-5D Health States: A Study in the Brazilian Population

BACKGROUND

. Logical inconsistency for health states preferences occurs when one logically worse health state, in terms of quality of life, is ranked higher than a logically better health state.

OBJECTIVE

. This study explores the presence of inconsistent responses for the EQ-5D health states valuations in a Brazilian population survey. It compares the level of inconsistency in 3 preference-based methods: ranking, visual analog scale (VAS), and time tradeoff (TTO). The influence of EQ-5D health state descriptions is explored by examining the distance between states using a city-block metric as an indicator of proximity. Moreover, it examines the association between formal education and the presence of inconsistencies, as well as the effect of removing inconsistent respondents on the estimation of social value sets from TTO and VAS.

METHODS

. Data came from a valuation study with 3362 literate individuals aged between 18 and 64 years living in urban areas of Minas Gerais state, Brazil. Logical inconsistency was assessed using the percentage of inconsistent respondents and inconsistency rate. A logistic model was estimated to assess the association between formal education and the logical inconsistency. Societal preferences were estimated excluding inconsistent respondents considering city-block metric.

RESULTS

. The percentage of inconsistent respondents and inconsistency rate are similar for TTO and ranking and lower for VAS. The probability of being inconsistent is higher among less educated groups in ranking and TTO. Inconsistency decreases with distance for all 3 methods. The removal of inconsistent individuals by considering city-block distance improves TTO estimation of social value sets.

CONCLUSION

. Findings suggest that removal of inconsistencies in TTO should consider city-block distance. For VAS, inconsistencies are not associated with formal education and do not affect social value set estimation.

How dead is dead? Qualitative findings from participants of combined traditional and lead-time time trade-off valuations

PURPOSE

The EuroQol Valuation Technology (EQ-VT) uses traditional time trade-off (tTTO) for health states better than dead and lead-time TTO (LT-TTO) for states worse than dead to elicit a value (-1.0 to +1.0) for each health state. In the Canadian EQ-5D-5L Valuation study which used the EQVT platform, we observed an unexpected peak in frequency of "0" values and few negative values, particularly in the range of 0 to -0.5. To better understand this finding, we sought to explore respondents' thought processes while valuing a health state, and their understanding of the tTTO and LT-TTO exercises.

METHODS

Qualitative semi-structured interviews were conducted with EQVT task respondents. Questions focused on valuations of health states as: (a) Same as dead in tTTO, (b) Worse than dead in tTTO but changed to same as dead in LT-TTO, (c) Worse than dead in LT-TTO, and (d) Worse than dead in LT-TTO with trading off all 10 years. Data were analyzed using content and thematic analysis.

RESULTS

Mean age of participants (N = 70) was 40 ± 18.1 years, 60% female, and 76% Caucasian. Participants provided similar reasons for valuing a health state same as or worse than dead. Many participants expressed confusion about worse than dead valuations, distinction between same as and worse than dead, and the transition from tTTO to LT-TTO. A few indicated that the addition of 10 years of full health in the LT-TTO influenced their valuations.

CONCLUSIONS

The transition from tTTO to LT-TTO in the EQVT was confusing to participants, whereby some health state valuations around this transition appeared to be arbitrary.

Exclusion Criteria in National Health State Valuation Studies: A Systematic Review

BACKGROUND

Health state valuation data are often excluded from studies that aim to provide a nationally representative set of values for preference-based health-related quality of life (HRQoL) instruments. The purpose was to provide a systematic examination of exclusion criteria used in the derivation of societal scoring algorithms for preference-based HRQoL instruments.

METHODS

Data sources included MEDLINE, official instrument websites, and publication reference lists. Analyses that used data from national valuation studies and reported a scoring algorithm for a generic preference-based HRQoL instrument were included. Data extraction included exclusion criteria and associated justifications, exclusion rates, the characteristics of excluded respondents, and analyses that explored consequential implications of exclusion criteria on the respective national tariff.

RESULTS

Seventy-six analyses (from 70 papers) met the inclusion criteria. In addition to being excluded for logical inconsistencies, respondents were often excluded if they valued fewer than 3 health states or if they gave the same value to all health states. Numerous other exclusion criteria were identified, with varying degrees of justification, often based on an assumption that respondents did not understand the task or as a consequence of the chosen statistical modeling techniques. Rates of exclusion ranged from 0% to 65%, with excluded respondents more likely to be older, less educated, and less healthy. Limitations included that the database search was confined to MEDLINE; study selection focused on national valuation studies that used standard gamble, time tradeoff, and/or visual analog scale techniques; and only English-language studies were included.

CONCLUSION

Exclusion criteria used in national valuation studies vary considerably. Further consideration is necessary in this important and influential area of research, from the design stage to the reporting of results.

The better than dead method: feasibility and interpretation of a valuation study

BACKGROUND

Traditionally, the valuation of health states worse than being dead suffers from two problems: [1] the use of different elicitation methods for positive and negative values, necessitating arbitrary transformations to map negative to positive values; and [2] the inability to quantify that values are time dependent. The Better than Dead (BTD) method is a health-state valuation method where states with a certain duration are compared with being dead. It has the potential to overcome these problems.

OBJECTIVES

To test the feasibility of the BTD method to estimate values for the EQ-5D system.

METHODS

A representative sample of 291 Dutch respondents (aged 18-45 years) was recruited. In a web-based questionnaire, preferences were elicited for a selection of 50 different health states with six durations between 1 and 40 years. Random-effects models were used to estimate the effects of socio-demographic and experimental variables, and to estimate values for the EQ-5D. Test-retest reliability was assessed in 41 respondents.

RESULTS

Important determinants for BTD were a religious life stance [odds ratio 4.09 (2.00-8.36)] and the educational level. The fastest respondents more often preferred health-state scenarios to being dead and had lower test-retest reliability (0.45 versus 0.77 and 0.84 for fast, medium and slow response times, respectively). The results showed a small number of so-called maximal endurable time states.

CONCLUSION

Valuating health states using the BTD method is feasible and reliable. Further research should explore how the experimental setting modifies how values depend on time.

Qualitative and Quantitative Analysis of Interviewer Help Answering the Time Tradeoff

OBJECTIVES

The time tradeoff (TTO) is an important method to directly obtain health utilities. Challenges of the TTO are, among others, "nontraders" and illogical answers. In TTO interviews, these challenges are resolved by the interviewer. In web-based TTOs, training procedures and logical checks are used based on the views of the researchers. As web-based TTOs will be used more often in the future, we investigated how respondents arrive at their ratings to determine the help they require.

METHODS

In 2 earlier studies performed by this research group, respondents valued 6 EQ-5D states on a TTO. Respondents were asked to think out loud, and all interviews were audiotaped. A random selection of these interviews were transcribed and double-coded by two independent raters, using a priori and inductive coding until saturation was reached. Based on the retrieved mistakes and comments, a list of frequently asked questions (FAQ) was developed.

RESULTS

In total, 91 interviews were coded. In all, 85% made at least 1 mistake, 41% made a misreading/miscalculation, 70% misunderstood the tradeoff, 27% misunderstood the EQ-5D dimensions, 29% misunderstood the scenario, 45% made a comment about the TTO, and 43% expressed frustration. More misunderstandings were reported in the Peeters study, which was performed in a realistic setting, whereas the van Osch study was conducted in a more ideal setting. Misunderstandings of the scenario were mosly reported by patients.

CONCLUSIONS

Almost all respondents need interviewer help. This may have implications for the validity of interviewer-based TTO elicitations when social acceptability bias is an issue or with explicit hypothesis and the interviewer is not blinded. The FAQ list can be used to standardize interviewer help or as a help function in a web-based TTO.

Time trade-off and attitudes toward euthanasia: implications of using 'death' as an anchor in health state valuation

PURPOSE

Health state values are by convention anchored to 'perfect health' and 'death.' Attitudes toward death may consequently influence the valuations. We used attitudes toward euthanasia (ATE) as a sub-construct for attitudes toward death. We compared the influence on values elicited with time trade-off (TTO), lead-time TTO (LT-TTO) and visual analogue scale (VAS).Since the 'death' anchor is most explicit in TTO, we hypothesized that TTO values would be most influenced by ATE.

METHODS

Respondents valued eight EQ-5D health states with VAS, then TTO (n = 328) or LT-TTO (n = 484). We measured ATE on a scale from -2 (fully disagree) to 2 (fully agree) and used multiple linear regressions to predict VAS, TTO, and LT-TTO values by ATE, sex, age, and education.

RESULTS

A one-point increase on the ATE scale predicted a mean TTO value change of -.113 and LT-TTO change of -.072. Demographic variables, but not ATE, predicted VAS values.

CONCLUSIONS

TTO appears to measure ATE in addition to preferences for health states. Different ways of incorporating death in the valuation may impact substantially on the resulting values. 'Death' is a metaphysically unknown concept, and implications of attitudes toward death should be investigated further to evaluate the appropriateness of using 'death' as an anchor.

Ordering errors, objections and invariance in utility survey responses: a framework for understanding who, why and what to do

BACKGROUND

Utilities are the quantification of the perceived quality of life associated with any health state. They are used to calculate QALYs, the outcome measure in cost-utility analysis. Generally measured through surveys of individuals, utilities often contain apparent or unapparent errors that can bias resulting values and QALYs calculated from these values.

OBJECTIVE

The aim of this study was to improve direct health utility elicitation methodology through the identification of the types of survey responses that indicate errors and objections, and the reasons underlying them.

METHODS

We conducted a systematic review of the medical (PubMed), economics (EconLit) and psychology (PsycINFO) literature from 1975 through June 2010 for articles describing the types and frequency of errors and objections in directly elicited utility survey responses, and strategies to address these responses. Primary data were collected through an internet-based utility survey (standard gamble) of community members to identify responses that indicate error or objections. A qualitative telephone survey was conducted among a subset of respondents with these types of responses using an open-ended protocol to elicit rationales for them.

RESULTS

A total of 11 papers specifically devoted to errors, objections and invariance in utility responses have been published since the mid-1990s. Error/objection responses can be broadly categorized into ordering errors (which include illogical and inconsistent responses) and objections/invariance (which include missing data, protest responses and refusals to trade time or risk in utility questions). Reported frequencies of respondents making ordering errors ranged from 5% to 100%, and up to 35% of respondents have been reported as objecting to the survey or task in some manner. Changes in the design, administration and analysis of surveys can address these potentially problematic responses. Survey data (n = 398) showed that individuals who provided invariant responses (n = 26) reported the lowest level of difficulty with the survey and often identified as religious (23% of invariant responders found the survey difficult vs 63% of all responders, and 77% of invariant responders identified as religious compared with 56% of entire sample; p < 0.05 for both). Respondents who provided illogical responses (n = 50) were less likely to be college educated (56% of illogical responders vs 73% of entire sample; p < 0.05), and less likely to be confident in their responses (62% vs 75% of entire sample; p < 0.05). Qualitative interviews (n = 42) following the survey revealed that the majority of ordering errors were a result of confusion, lack of attention or difficulty in responding to the survey on the part of the respondent, while invariant responses were often considered and thoughtful reactions to the premise of valuing health using the standard gamble task.

CONCLUSIONS

Rationales for error/objection responses include difficulty in articulating preferences or misunderstanding with a complex survey task, and also thoughtful and considered protestations to the task. Mechanisms to correct unintentional errors may be useful, but cannot address intentional responses to elements of the measurement task. Identification and analysis of the prevalence of errors and objections in responses in utility data sets are essential to understanding the accuracy and precision of utility estimates and analyses that depend thereon.

Correspondence between EQ-5D health state classifications and EQ VAS scores

BACKGROUND

The EQ-5D health-related quality of life instrument comprises a health state classification followed by a health evaluation using a visual analogue scale (VAS). The EQ-5D has been employed frequently in economic evaluations, yet the relationship between the two parts of the instrument remains ill-understood. In this paper, we examine the correspondence between VAS scores and health state classifications for a large sample, and identify variables which contribute to determining the VAS scores independently of the health states as classified.

METHODS

A UK trial of management of low-grade abnormalities detected on screening for cervical pre-cancer (TOMBOLA) provided EQ-5D data for over 3,000 women. Information on distress and multi-dimensional health locus of control had been collected using other instruments. A linear regression model was fitted, with VAS score as the dependent variable. Independent variables comprised EQ-5D health state classifications, distress, locus of control, and socio-demographic characteristics. Equivalent EQ-5D and distress data, collected at twelve months, were available for over 2,000 of the women, enabling us to predict changes in VAS score over time from changes in EQ-5D classification and distress.

RESULTS

In addition to EQ-5D health state classification, VAS score was influenced by the subject's perceived locus of control, and by her age, educational attainment, ethnic origin and smoking behaviour. Although the EQ-5D classification includes a distress dimension, the independent measure of distress was an additional determinant of VAS score. Changes in VAS score over time were explained by changes in both EQ-5D severities and distress. Women allocated to the experimental management arm of the trial reported an increase in VAS score, independently of any changes in health state and distress.

CONCLUSION

In this sample, EQ VAS scores were predictable from the EQ-5D health state classification, although there also existed other group variables which contributed systematically and independently towards determining such scores. These variables comprised psychological disposition, socio-demographic factors such as age and education, clinically-important distress, and the clinical intervention itself.

TRIAL REGISTRATION

ISRCTN34841617.

The impact of seizures and adverse effects on global health ratings

This study was undertaken to explore the perceived impact of having a seizure (SZ) compared with having an adverse effect (AE). Patients (N=201) with partial-onset epilepsy taking two or more antiepileptic drugs (AEDs) rated their health state from 0 to100 based on their health today, hypothetical health if experiencing a SZ today, and hypothetical health if experiencing an AE today. Overall health status ratings (HLTH) declined as SZ frequency increased (P=0.01). Perceived decrements in HLTH with SZs were greatest for patients with the least frequent SZs (P=0.001) and the most recent SZs (P=0.004). Perceived decrements in HLTH with SZs compared with AEs (SZ-AE) differed across SZ recency groups (P<0.05 except for muscle incoordination and weakness). Patients with the more remote SZs were most concerned with SZ control; patients with more recent SZs were more sensitive to AED side effects. These data provide insight into the risk-benefit concerns of patients at equipoise when addressing the efficacy and AEs of AEDs.

Why people refuse to make tradeoffs in person tradeoff elicitations: a matter of perspective?

OBJECTIVE

Person tradeoff (PTO) elicitations assess people's values for health states by asking them to compare the value of treatment programs. For example, people might be asked how many patients need to be cured of health condition X to equal the benefit of curing 100 people of condition Y. However, when faced with PTO elicitations, people frequently refuse to make quantifiable tradeoffs, exhibiting 2 kinds of refusals: 1) They say that 2 treatment programs have equal value, that curing 100 of X is just as good as curing 100 of Y, even if X is a less serious condition than Y, or 2) they say that the 2 programs are incomparable, that millions of people need to be cured of X to be as good as curing 100 of Y. The authors explore whether people would be more willing to make tradeoffs if the focus was changed from trading off groups of patients to choosing the best decision or evaluating treatment benefits.

DESIGN

. Two randomized trials used diverse samples (N=2400) via the Internet to test for the effect of perspective on refusal rates. The authors predicted that perspectives that removed people from decision-making roles would increase their willingness make tradeoffs.

RESULTS

Contrary to expectations, refusal rates increased when people were removed from decision-making roles. In fact, the more pressure put on people to make a decision, the less likely they were to refuse to make tradeoffs.

CONCLUSION

To reduce PTO refusals, it is best to adopt a decision-maker perspective.

Is there a case for using visual analogue scale valuations in cost-utility analysis?

This paper critically reviews theoretical and empirical propositions regarding visual analogue scale (VAS) valuations of health states and their use in cost-utility analysis (CUA). A widely repeated assertion in the economic evaluation literature is the inferiority, on theoretical grounds, of VAS valuations. Five common criticisms are: VAS lacks a theoretical foundation; VAS values are not 'choice based'; VAS values are not consistent with utility-under-uncertainty requirements; context and range effects observed in VAS valuation data mean that they cannot even be considered to represent measurable value functions; and when completing a VAS, people are not trying to express values. We address each of these points: the VAS does have a theoretical basis, being entirely consistent with the non-welfarist foundations of QALYs and CUA; the 'choiceless' nature of the VAS is incorrectly judged by stated preference criteria relevant to monetary rather than health state valuations, and VAS valuations do in any case involve an element of choice; because valuations are intended for use in social decision-making, it may be advantageous that VAS values are elicited under conditions of certainty; although there are measurement problems with the VAS, means such as better design and transformations of data can deal with these; and with any method of eliciting values, it is unrealistic to expect people consciously to think in terms of social science constructs such as utilities.Moreover, there are problems, both theoretical and empirical, with alternative methods. Selection of the appropriate valuation method should be based on empirical performance, and in this the VAS has important advantages. We conclude that there are strong grounds for disputing the consensus view against the VAS and challenge those who hold it to deploy more convincing arguments and evidence in favour of alternative methods. However, we identify areas where further research is required to establish and consolidate the potential of the VAS as a valuation method.

Understanding VAS valuations: qualitative data on the cognitive process

Eliciting people's value is a central pursuit in health economics. We explored approaches to valuing a health state on a visual analog scale (VAS). Additionally, we examined whether dual processing (an interaction between automatic and controlled information processing) occurred during VAS valuation. In the first experiment, respondents were probed for their approach after valuation on a VAS. After inductive generalization, we grouped the approaches: (1) 'Sort-of ' (automatic processing), (2) 'Bisection of line first', (3) 'Numerical expression', and (4) 'Dividing into smaller segments'. In the second experiment, a short questionnaire followed the VAS in which these approaches were systematically assessed, as was awareness of the approach used, intention to re-use the approach the next time (confidence), and basis of the approach. Data showed that the 'Sort-of' approach was used most often, followed by the 'Bisection-first' approach. We argue that dual processing occurs during performance on the VAS. Awareness of the approach used was lower when an intuitive approach was used. A reasoned approach had a higher correlation with confidence. Thus, awareness of approach may improve reliability. Reducing the number of health states to be valued concurrently diminishes the complexity of the task; this may enhance the validity of the VAS.

A "new and improved" EQ-5D valuation questionnaire? Results from a pilot study

Notwithstanding its widespread use, the standard questionnaire used to elicit visual analogue scale valuations for EQ-5D states is well known to suffer from problems with missing values (particularly for the state "dead") and logical inconsistencies. This contribution reports on efforts to redesign the questionnaire to overcome these problems and the results from its use in a pilot study. The redesigned questionnaire asks respondents to provide a numerical score for each state (instead of drawing lines to a visual analogue scale) and employs a new method for valuing "dead". A pilot study was undertaken to gauge the effects of these innovations, over and above other cosmetic changes to the questionnaire. The redesigned questionnaire was found to result in fewer missing values, fewer exclusions and fewer logical inconsistencies. Mean re-scaled values for the health states remained virtually identical. The results suggest that scoring is a better way of eliciting self-completed valuations than scaling.