A novel approach for health state valuation: Multiple bounded dichotomous choice compared to the traditional standard gamble.

OBJECTIVE: to assess the feasibility of a new stated preference approach, the multiple bounded dichotomous choice (MBDC), designed to generate value sets for preference-based measurement of health-related quality of life. METHODS: MBDC and standard gamble (SG) tasks were completed to derive SF-6Dv2 value sets from a sample of the general population in Quebec, Canada. Participants were randomized between the two approaches: 6 health states were evaluated in SG and 11 health states in MBDC. Several models were used to estimate data in each approach, and the preferred models were chosen by using mean absolute error (MAE), logical consistency of parameters, and significance levels. Results of MBDC were compared with SG in terms of acceptability (self-reported difficulty and quality levels in answering, and completion time), consistency (monotonicity of model coefficients), accuracy (standard errors), dimensions coefficient magnitude, correlation between the value sets estimated, and the range of estimated values. The intra-class correlation coefficient (ICC) was computed to assess value sets' consistency. RESULTS: Out of 655 individuals who completed MBDC tasks and 828 who completed SG tasks, a total of 585 participants for MBDC and 714 for SG tasks were included for analysis. The preferred models for both approaches were GLS Tobit. No significant difference was observed in self-reported difficulties and qualities in answers among approaches, but MBDC had less excluded participants and was less prone to report difficulties in answering. Additionally, completion time in the MBDC group was significantly lower (99.80 vs 68.12 s). Most standard errors in the MBDC were lower than those in SG, and the number of non-significant parameters was also lower. The range of utility values generated by MBDC tended to be wider (-0.372 to 1) than those generated by the SG (-0.137 to 1) and the number of worse-than-dead states in MBDC (0.91%) was higher than for SG (0.08%). The Pain dimension was identified as the most significant, while the Vitality dimension showed the lowest significant decrement. Both approaches exhibited a tendency to overestimate severe health state values and underestimate better health state values. The correlation and ICC between the two value sets were 0.937 and 0.983, respectively. CONCLUSION: Based on empirical evidence, it can be inferred that the MBDC method is not only feasible but also holds the potential to generate meaningful and well-informed preference data from respondents. This approach can be used to derive a value set for preference-based instrument.

Is anchoring at 'dead' a theoretical requirement for health state valuation?

Values that accompany generic health measures are typically anchored at 1 = full health and 0 = dead. Some health states may then be considered 'worse than dead' (WTD) and assigned negative values, which causes fundamental measurement problems. In this paper, we challenge the assumption that anchoring values at 'dead = 0' is necessary for quality-adjusted life year (QALY) estimation. We summarise the role of 'dead' in health state valuation and consider three critical questions: (i) whether the measurement properties of health state values require 'dead'; (ii) whether 'dead' needs to be valued relative to health states; and (iii) whether values for states WTD are meaningful or useful. We conclude that anchoring 0 at dead is not a requirement of health status measurement or cost-effectiveness analysis. This results from reframing QALYs as the relevant unit of measurement and reframing values as being derived from QALYs rather than the reverse.

COVID-19-related health utility values and changes in COVID-19 patients and the general population: a scoping review.

PURPOSE: To summarise the diverse literature reporting the impact of COVID-19 on health utility in COVID-19 patients as well as in general populations being affected by COVID-19 control policies. METHODS: A literature search up to April 2023 was conducted to identify papers reporting health utility in COVID-19 patients or in COVID-19-affected general populations. We present a narrative synthesis of the health utility values/losses of the retained studies to show the mean health utility values/losses with 95% confidence intervals. Mean utility values/losses for categories defined by medical attendance and data collection time were calculated using random-effects models. RESULTS: In total, 98 studies-68 studies on COVID-19 patients and 30 studies on general populations-were retained for detailed review. Mean (95% CI) health utility values were 0.83 (0.81, 0.86), 0.78 (0.73, 0.83), 0.82 (0.78, 0.86) and 0.71 (0.65, 0.78) for general populations, non-hospitalised, hospitalised and ICU patients, respectively, irrespective of the data collection time. Mean utility losses in patients and general populations ranged from 0.03 to 0.34 and from 0.02 to 0.18, respectively. CONCLUSIONS: This scoping review provides a summary of the health utility impact of COVID-19 and COVID-19 control policies. COVID-19-affected populations were reported to have poor health utility, while a high degree of heterogeneity was observed across studies. Population- and/or country-specific health utility is recommended for use in future economic evaluation on COVID-19-related interventions.

Use of the visual analogue scale for health state valuation: a scoping review.

OBJECTIVES: The visual analogue scale (VAS) has been used in the context of health and healthcare for various purposes, for example, to measure pain and to provide a single-index measure of health-related quality of life (HRQoL). This scoping review aims to describe how the VAS has been used for health state valuation in the published literature. METHODS: The search was carried out in Medline, Web of Science and PsycInfo. The findings of the included articles were tabulated and presented descriptively using frequencies and proportions. RESULTS: The database search yielded 4856 unique articles, out of these, 308 were included. In 83% of the articles, the main purpose for using a VAS was to value health states. The two most common perspectives when valuing health states with a VAS were hypothetical (44%) and own health (34%). Some (n = 14) articles used the VAS in the context of economic evaluations, including calculating quality-adjusted life years (QALYs). A large variation in the design of the VAS was found, including the description of the lower and upper anchors. Advantages and disadvantages with using a VAS were mentioned in 14% of the included articles. CONCLUSION: The VAS has been a common method for valuing health states, both as a stand-alone method and in combination with other valuation methods. Despite its widespread use, the design of the VAS has been inconsistent which makes comparison of results across studies challenging. Further research on the role of using the VAS in economic evaluations is warranted.

Experience-based health state valuation using the EQ VAS: a register-based study of the EQ-5D-3L among nine patient groups in Sweden.

BACKGROUND: The EQ VAS component of the EQ-5D questionnaire has been used to assess patients' valuation of their own health besides its use for self-reporting of overall health status. The objective of the present study was to identify patients' valuation of EQ-5D-3L health states using the EQ VAS in different patient groups over time and in comparison to the general population. METHODS: Data were obtained from patients from nine National Quality Registers (n = 172,070 patients) at baseline and at 1-year follow-up and compared with data from the general population (n = 41,761 participants). The correlation between EQ VAS scores and EQ-5D-3L index based on the Swedish experience-based VAS value set was assessed. Ordinary least squares (OLS) regression models were used to determine the association between EQ-5D-3L dimensions and EQ VAS valuation. RESULTS: EQ VAS scores showed consistency with severity of health states both at baseline and at 1-year follow-up in the nine selected EQ-5D-3L health states. The regression models showed mostly consistent decrements by severity levels in each dimension at both time points and similar to the general population. The dimension mainly associated with inconsistency was the self-care severity level three. Problems in the anxiety/depression dimension had the largest impact on overall health status in most of the patient groups and the general population. CONCLUSION: The study has demonstrated the important role EQ VAS can play in revealing patients' valuation of their health and showed the variation in valuation of EQ-5D-3L dimensions and levels of severity across different patient groups.

A national survey of Iranian general population to estimate a value set for the EQ-5D-5L.

OBJECTIVES: The main aim of this study is to estimate a national value set of the EQ-5D-5L questionnaire for Iran. METHODS: The composite time trade-off (cTTO) and discrete choice experiment (DCE) methods; and the protocol for EuroQol Portable Valuation Technology (EQ-PVT) were used to estimate the Iran national value set. 1179 face-to-face computer-assisted interviews were conducted with adults that were recruited from five Iran major cities in 2021. Generalized least squares, Tobit, heteroskedastic, logit, and hybrid models were used to analyze the data and to identify the best fitting model. RESULTS: According to the logical consistency of the parameters, significance levels and prediction accuracy indices of the MAE; a heteroscedastic censored Tobit hybrid model combining cTTO and DCE responses was considered as the best fitting model to estimate the final value set. The predicted values ranged from - 1.19 for the worst health state (55555) to 1 for full health (11111), with 53.6% of the predicted values being negative. Mobility was the most influential dimension on health state preference values. CONCLUSIONS: The present study estimated a national EQ-5D-5L value set for Iranian policy makers and researchers. The value set enables the EQ-5D-5L questionnaire to use to calculate QALYs to assist the priority setting and efficient allocation of limited healthcare resources.

Time and lexicographic preferences in the valuation of EQ-5D-Y with time trade-off methodology.

In the valuation of EQ-5D-Y-3L, adult respondents are asked to complete composite time trade-off (cTTO) tasks for a 10-year-old child. Earlier work has shown that cTTO utilities elicited in such a child perspective are generally higher than when adults take their own perspective. We explore how differences in time preference in child and adult perspectives could explain this effect. Furthermore, as cTTO valuation in a child perspective involves explicit consideration of immediate death for a child, we also consider how cTTO utilities could be affected by decision-makers lexicographically avoiding death in children. We report the results of an experiment in which 219 respondents valued 5 health states in both adult and child perspectives with either a standard cTTO or a lead-time TTO only approach, in which immediate death is less focal. Time preferences were measured in both perspectives. Our results suggest that utilities were lower when lead-time TTO, rather than cTTO, was used. We find large heterogeneity in time preference in both perspectives, with predominantly negative time preference. The influence of time preferences on utilities, however, was small, and correcting for time preferences did not reduce differences between utilities elicited in both perspectives. Surprisingly, we found more evidence for differences in utilities between adult and child perspectives when lead-time TTO was used. Overall, these results suggest that time and lexicographic preferences affect time trade-off valuation in child and adult perspectives, but are not the explanation for differences between these perspectives. We discuss the implications of our findings for EQ-5D-Y-3L valuation.

Completing the time trade-off with respondents who are older, in poorer health or with an immigrant background in an EQ-5D-5L valuation study.

OBJECTIVES: To determine the effects of age, immigrant background, and poor self-reported health in a general population sample on the probability of non-completion or slow completion of the time trade-off (TTO). METHODS: We used data from an interrupted Norwegian EQ-5D-5L valuation study conducted between 2019 and 2020. All participants responded to background items, irrespective of completion. We used mixed effect logistic regression analysis to assess the effect of old age, poor health, and immigrant background on the probability of non-completion of the TTO, and, for those who completed the TTO, of slow completion times. RESULTS: First experiences from a Norwegian valuation study were that 29 (5.5%) respondents failed to complete the TTO tasks. For those reporting age over 65 years, poor health, or an immigrant background, 12% failed to complete the TTO. Adjusted odds ratios for predictors of non-completion were statistically significant (age > 65 years, 8.3; EQ-VAS ≤ 50, 3.49; immigrant background, 4.56). Being over 65 years or with an immigrant background also predicted slow completion of both the introduction and TTO tasks. CONCLUSIONS: High age, poor health, and immigrant status increased the risk of not being able to complete the TTO tasks, and of slow completion. Higher non-completion rates and increased completion times suggest that elements of the TTO may be demanding for some respondent groups, with possible implications for representativeness.

Hypothetical versus experienced health state valuation: a qualitative study of adult general public views and preferences.

OBJECTIVES: Responses from hypothetical and experienced valuation tasks of health-related quality of life differ, yet there is limited understanding of why these differences exist, what members of the public think about them, and acceptable resolutions. This study explores public understanding of, opinions on, and potential solutions to differences between hypothetical versus experienced responses, in the context of allocating health resources. METHODS: Six focus groups with 30 members of the UK adult public were conducted, transcribed verbatim, and analysed using framework analysis. Participants self-completed the EQ-5D-5L, before reporting the expected consequences of being in two hypothetical EQ-5D-5L health states for ten years. Second, participants were presented with prior results on the same task from a public (hypothetical) and patient (experienced) sample. Third, a semi-structured discussion explored participants': (1) understanding, (2) opinions, and (3) potential resolutions. RESULTS: Twenty themes emerged, clustered by the three discussion points. Most participants found imagining the health states difficult without experience, with those aligned to mental health harder to understand. Participants were surprised that health resource allocation was based on hypothetical responses. They viewed experienced responses as more accurate, but noted potential biases. Participants were in favour of better informing, but not influencing the public. Other solutions included incorporating other perspectives (e.g., carers) or combining/weighting responses. CONCLUSION: Members of the UK public appear intuitively not to support using potentially uninformed public values to hypothetical health states in the context of health resource allocation. Acceptable solutions involve recruiting people with greater experience, including other/combinations of views, or better informing respondents.

Understanding community perception and disability weights - A qualitative exploration of reasons associated with values in two states of India.

Background: Health state valuation attempts to evaluate health states based on the perception of individuals. The values are used to derive disability weights (DWs) -an important metric for estimation of disability-adjusted life years and thereby calculation of the burden of diseases. Several studies have calculated DWs using different methods of valuation, however, very few have attempted to explore the underlying cause for assigning values to different health states. This study aims to document the perceptions, preferences, and social context in assigning DWs to given health states. Methods: A total of 42 community members and 21 service providers (from public and private sectors) across urban and rural Odisha and Telangana were interviewed between July to September 2018. A face-to-face in-depth interview and a rank ordering technique through card sort exercise was employed to explore reasons and perceptions of individuals in the context of health states using the thematic framework approach. Findings: Six themes emerged through analysis: awareness of the health state, nature of the disease, disease consequences, treatment-related issues, social implications, and case burden. Each theme captured an individual's reason for valuing one health state as different from the other, with differences and/or similarities between community members and service providers. Conclusion: Our study provides a comprehensive comparison between contrasting groups of individuals, thereby suggesting mere acceptance of 'experts' reasoning may not always suffice. Further research studies in the future need to be conducted for a better insight into the health perspective of a culturally diverse community. It can also help estimate the burden of disease for decision making and resource allocation in developing countries.

Do they just know more, or do they also have different preferences? An exploratory analysis of the effects of self-reporting serious health problems on health state valuation.

BACKGROUND: Health state valuation is often conducted by people valuing either only their own health state (experience-based valuation) or several stylised states (hypothetical valuation). The approach used can affect the elicited values, but it is not clear whether this is caused by different understandings of the states (an "information mechanism") and/or by different opinions of the states (a "preference mechanism"). Justifying privileging the valuations of those with the relevant health state experience solely because they are better informed is insufficient when their opinions differ. This study proposes a new framework to examine the effect of having health problems on health state valuation by distinguishing "within-dimensional" effects (which can be due to better information or due to differences in opinion) and "cross-dimensional" effects (which must be due to differences in opinion). METHODS: Secondary data from the UK that valued EQ-5D-5L using Discrete Choice Experiments with duration (DCETTO) are remodelled controlling for whether a respondent self-reports serious (viz., severe or extreme) problems in "pain or discomfort" (PD) or "anxiety or depression" (AD). The main analysis uses respondents who have serious PD or serious AD alongside matched respondents who do not, and assumes constant proportional time trade-off. RESULTS: Self-reporting serious PD or serious AD problems has no within-dimensional effect on health state preferences. However, self-reporting serious AD problems has negative cross-dimensional effects on the utility of having any problem in PD, which suggests that the preference mechanism is present. A similar pattern holds when all available (unmatched) data are used and when constant proportional time trade-off is relaxed. CONCLUSIONS: Findings consistent with the preference mechanism indicate that those with serious health problems may have different opinions on the value of health states compared to the rest of the population, which has normative implications for the debate on which values to use.

Discrete choice experiment with duration versus time trade-off: a comparison of test-retest reliability of health utility elicitation approaches in SF-6Dv2 valuation.

OBJECTIVES: To evaluate and compare the test-retest reliability of discrete choice experiments with duration (DCETTO) and time trade-off (TTO) in the Chinese SF-6Dv2 valuation study. METHODS: During face-to-face interviews, a representative sample of the Chinese general population completed 8 TTO tasks and 10 DCETTO tasks. Retest interviews were conducted after two weeks. For both DCETTO and TTO, the consistency of raw responses between the two tests was firstly evaluated at the individual level. Regressions were conducted to investigate the association between the test-retest reliability and the respondents' characteristics and the severity of health states. Consistency was then analyzed at the aggregate level by comparing the rank order of the coefficients of dimensions. RESULTS: In total, 162 respondents (51.9% male; range 18-80 years) completed the two tests. The intraclass correlations coefficient 0.958 for TTO, with identical values accounting for 59.3% of observations. 76.4% of choices were identical for DCETTO, with a Kappa statistic of 0.528. Respondents' characteristics had no significant impact while the severity of health states valued in TTO and DCETTO tasks had a significant impact on the test-retest reliability. Both approaches produced relatively stable rank order of dimensions in constrained model estimations between test and retest data. CONCLUSIONS: Individual responses of both approaches are relatively stable over time. The rank orders of dimensions in model estimations between test and retest for TTO and DCETTO are also consistent. The differences of utility estimation between the two tests for DCETTO need to be further investigated based on a larger sample size.

Methodological similarities and variations among EQ-5D-5L value set studies: a systematic review.

OBJECTIVES: (1) To descriptively compare the selected elements of valuation methods for EQ-5D-5L value set studies, (2) to compare the characteristics of the value sets, and (3) to examine the associations between the selected elements of valuation methods and the EQ-5D-5L value sets. METHODS: A systematic literature search of EQ-5D-5L valuation studies from 1 January 2009 to 22 April 2021 was conducted in selected databases. Following the initial search, we also explored additional studies published during the completion of the final version of the manuscript. Similarities and variations for selected elements of valuation methods were descriptively compared. The relative importance of dimensions, utility decrements between the levels, and distribution of the utility scores were used to compare value sets. A meta-regression analysis examined the associations between the selected methodological elements and the utility scores and dimension levels of EQ-5D-5L. RESULTS: A total of 31 studies were included in this review. Methodological similarities centered around data collection and preference elicitation method. On the other hand, variations include sampling technique, sample size, and value set modeling. The variations in value sets based on the relative importance of dimension, decrement in utility score, and distribution of utility score across countries were observed. Although the distribution of the utility scores differed across countries, higher levels of each dimension tended to have a larger decrement in the utility scores. Mean utility scores for the experience-based value sets were higher than those estimated using stated choice methods. The selected methodological elements were not significantly associated with the mean predicted utility scores or most dimension-level coefficients. CONCLUSIONS: EQ-5D-5L health state valuation methods and characteristics of value sets differed across studies. The impact of the variation of methodological elements on the value sets should be further investigated.

Disability Weights Estimates From India in 2018: Measurements From Community Members From Two Distinct States of India.

Background: India is undergoing a rapid demographic and epidemiologic transition. Thus demanding prioritization of diseases based on burden estimation is befitting our cultural diversity. Disability weights (DWs) by Global burden of disease (GBD) studies may not be representative. Hence, a study was conducted to estimate state-specific disability weights to capture the community health perceptions that included urban-rural settings as well as different socio-economic and literacy levels. Methods: A total of 2,055 community members (participants) from two distinct states of India, Odisha and Telangana, were interviewed to assign disability weights to the selected 14 health states based on the state burden and relevance. Each health state was described to the participants using pictorial representations of the health states and valuated using visual analog scale and card sort methods. Results: We noted that DWs in Odisha ranged from 0.32 (0.30-0.34) for upper limb fracture due to road traffic accident (least severe) to 0.90 (0.88-0.93) for breast cancer (most severe) among the 14 health states. While, in Telangana, diarrhea was considered least severe [DW = 0.22 (0.19-0.24)] and breast cancer remained most severe [DW = 0.85 (0.83-0.88)] as in Odisha. Marked difference in the DWs for other health states was also seen. Further, on comparison of community weights with GBD weights using Spearman correlation, we observed a low correlation (ρ = 0.104). Conclusion: Our study provides community-based findings that show how participants valued noncommunicable diseases higher than short-term ailments or infectious diseases. Additionally, the low correlation between GBD also suggests the need for local disability weights rather than universal acceptance. We therefore recommend that decisions in policy-making, especially for resource allocation and priority setting, need to be based not only on expert opinion but also include community in accordance with high scientific standards.

Why Do Adults Value EQ-5D-Y-3L Health States Differently for Themselves Than for Children and Adolescents: A Think-Aloud Study.

OBJECTIVES: Following protocol, adults value EQ-5D-Y-3L health states from the perspective of a 10-year-old child. It remains unclear why adults value health states differently for themselves than for a 10-year-old child and whether the latter perspective is representative of adults' preferences for the 8 to 15 years age range of the EQ-5D-Y-3L. This study examines the reasons underlying (potential) differences in adults' health-state preferences for themselves, a 10-year-old child, and 15-year-old adolescent. METHODS: We conducted semistructured interviews using a think-aloud protocol with 25 participants who performed valuation tasks in July 2020 to August 2020. Using the Framework Method, we developed 28 categories grouped under 5 themes that illustrated the differences emerging from the interviews. RESULTS: Participants (A) deemed it more straining to perform valuation tasks for a 10-year-old child and 15-year-old adolescent than for themselves, (B) had a stable self-image, but varied in whom they imagined as 10-year-old child and 15-year-old adolescent, (C) focused on different dimensions and levels for a 15-year-old adolescent than for a 10-year-old child and themselves, (D) had various thoughts about nonhealth-related factors that influenced their preferences, and (E) gave up relatively few life-years for a 10-year-old child and 15-year-old adolescent, also to avoid others bearing a grudge against them. CONCLUSIONS: Our results indicate that differences in adults' health-state preferences for themselves and a 10-year-old child largely result from differences in thoughts about nonhealth-related factors. They further indicate that health-state preferences for a 10-year-old child may not be representative of such preferences for the full EQ-5D-Y-3L age range.

Time trade-off with someone to live for: impact of having significant others on time trade-off valuations of hypothetical health states.

BACKGROUND: The TTO task involves giving up life years, i.e. living a shorter life, to avoid an undesirable health state. Despite being a hypothetical task, some respondents take other life factors into account when completing the task. This study explored the effect of having children and/or a partner on TTO valuations of hypothetical EQ-5D-5L health states in a valuation study of the general population. METHODS: The study used TTO data collected in a Norwegian EQ-5D-5L valuation study in 2019-2020, by one-to-one pc-assisted interviews following the EQ-VT protocol. We used regression modelling to determine the effect of significant others (having children or a partner) on disutility per health state from the TTO valuations. RESULTS: 430 respondents were included [mean age 43.8 (SD 15.9) years, 58% female, 48% with children, 68% with a partner, 25% with neither children nor partner]. Having children and/or a partner was associated with lowered willingness to trade life years translating to higher elicited health state utilities (p < 0.01). CONCLUSION: Having significant others, or the lack of having significant others, was associated with respondents' valuation of hypothetical health states using TTO, more so than traditional sampling variables such as age and sex. Inadequate representativeness in terms of having significant others could bias health state preference values in valuation studies.

Self vs. other, child vs. adult. An experimental comparison of valuation perspectives for valuation of EQ-5D-Y-3L health states.

OBJECTIVES: EQ-5D-Y-3L health states are valued by adults taking the perspective of a 10-year-old child. Compared to valuation of adult EQ-5D instruments, this entails two changes to the perspective: (i) child health states are valued instead of adult health states and: (ii) health states are valued for someone else instead of for oneself. Although earlier work has shown that these combined changes yield different values for child and adult health states that are otherwise equal, it currently remains unclear why. Hence, we aimed to disentangle the effects of both changes. METHODS: A sample of 205 students (mean age: 19.48) was surveyed. Each respondent completed visual analogue scale (VAS) and time trade-off (TTO) tasks for five EQ-5D-Y-3L states, using four randomly ordered perspectives: (i) self-adult (themselves), (ii) other-adult (someone their age), (iii) self-child (themselves as a 10-year-old), (iv) other-child (a child of 10 years old). We compared how each perspective impacted outcomes, precision and quality of EQ-5D-Y-3L valuation. RESULTS: Overall, differences between perspectives were consistent, with their direction being dependent on the health states and respondents. For VAS, the effect on outcomes of valuation depended on severity, but variance was higher in valuation with child perspectives. For TTO, we observed that EQ-5D-Y-3L states valued on behalf of others (i.e., children or adults) received higher valuations, but lower variances. CONCLUSION: The use of a different perspective appears to yield systematic differences in EQ-5D-Y-3L valuation, with considerable heterogeneity between health states and respondents. This may explain mixed findings in earlier work.

Valuing child and adolescent health: a qualitative study on different perspectives and priorities taken by the adult general public.

BACKGROUND: Quantitative health preference research has shown that different "perspectives", defined here as who is imagined to be experiencing particular health states, impact stated preferences. This qualitative project aimed to elucidate this phenomenon, within the context of adults' valuation of child and adolescent health states. METHODS: Six focus groups with 30 members of the UK adult public were conducted between December 2019 and February 2020 and analysed using framework analysis. Each focus group had two stages. First, participants individually completed time trade-off tasks and a pairwise task (mirroring a discrete choice experiment without duration) for two EQ-5D-Y health states, assuming a series of perspectives: (a) themselves at current age; (b) another adult; (c) 10-year old child; (d) themselves as a 10-year old child. Second, a semi-structured discussion explored their responses. RESULTS: Participants' views were often heterogeneous, with some common themes. Qualitatively, participants expressed a different willingness to trade-off life years for a 10-year old child versus themselves or another adult, and this differed by the health profile and child imagined. The same health states were often viewed as having a different impact on utility for a 10-year old child than adults. Imagining a 10-year old child is difficult and there is variation in who is imagined. Participants found answering based on their own-adult perspective most acceptable. There were no strong preferences for prioritising child health over working-age adults' health. CONCLUSIONS: If an adult sample is used to value child- and adolescent-specific health states it is important to consider the perspective employed. Members of the adult public provide different responses when different perspectives are used due to differences in the perceived impact of the same health states. If adults are asked to imagine a child, we recommend that sampling is representative for parental status, since this can affect preferences.

Variations in Patients' Overall Assessment of Their Health Across and Within Disease Groups Using the EQ-5D Questionnaire: Protocol for a Longitudinal Study in the Swedish National Quality Registers.

BACKGROUND: EQ-5D is one of the most commonly used questionnaires to measure health-related quality of life. It is included in many of the Swedish National Quality Registers (NQRs). EQ-5D health states are usually summarized using "values" obtained from members of the general public, a majority of whom are healthy. However, an alternative, which remains to be studied in detail, is the potential to use patients' self-reported overall health on the visual analog scale (VAS) as a means of capturing experience-based perspective. OBJECTIVE: The aim of this study is to assess EQ VAS as a valuation method with an experience-based perspective through comparison of its performance across and within patient groups, and with that of the general population in Sweden. METHODS: Data on nearly 700,000 patients from 12 NQRs covering a variety of diseases/conditions and nearly 50,000 individuals from the general population will be analyzed. The EQ-5D-3L data from the 12 registers and EQ-5D-5L data from 2 registers will be used in the analyses. Longitudinal studies of patient-reported outcomes among different patient groups will be conducted in the period from baseline to 1-year follow-up. Descriptive statistics and analyses comparing EQ-5D dimensions and observed self-assessed EQ VAS values across and within patient groups will be performed. Comparisons of the change in health state and observed EQ VAS values at 1-year follow-up will also be undertaken. Regression models will be used to assess whether EQ-5D dimensions predict observed EQ VAS values to investigate patient value sets in each patient group. These will be compared across the patient groups and with the existing Swedish experience-based VAS and time trade-off value sets obtained from the general population. RESULTS: Data retrieval started in May 2019 and data of patients in the 12 NQRs and from the survey conducted among the general population have been retrieved. Data analysis is ongoing on the retrieved data. CONCLUSIONS: This research project will provide information on the differences across and within patient groups in terms of self-reported health status through EQ VAS and comparison with the general population. The findings of the study will contribute to the literature by exploring the potential of self-assessed EQ VAS values to develop value sets using an experience-based perspective. TRIAL REGISTRATION: ClinicalTrials.gov NCT04359628; https://clinicaltrials.gov/ct2/show/NCT04359628. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/27669.