A Feasible Estimation of a "Corrected" EQ-5D Social Tariff.

OBJECTIVES: To demonstrate the feasibility of estimating a social tariff free of utility curvature and probability weighting biases and to test transferability between riskless and risky contexts. METHODS: Valuations for a selection of EQ-5D-3L health states were collected from a large and representative sample (N = 1676) of the Spanish general population through computer-assisted personal interviewing. Two elicitation methods were used: the traditional time trade-off (TTO) and a novel risky-TTO procedure. Both methods are equivalent for better than death states, which allowed us to test transferability of utilities across riskless and risky contexts. Corrective procedures applied are based on rank-dependent utility theory, identifying parameter estimates at the individual level. All corrections are health-state specific, which is a unique feature of our corrective approach. RESULTS: Two corrected value sets for the EQ-5D-3L system are estimated, highlighting the feasibility of developing national tariffs under nonexpected utility theories, such as rank-dependent utility. Furthermore, transferability was not supported for at least half of the health states valued by our sample. CONCLUSIONS: It is feasible to estimate a social tariff by using interviewing techniques, sample sizes, and sample representativeness equivalent to prior studies designed to generate national value sets for the EQ-5D. Utilities obtained in distinct contexts may not be interchangeable. Our findings caution against routinely taking transferability of utility for granted.

Testing Nonmonotonicity in Health Preferences.

OBJECTIVE: The main aim of this article is to test monotonicity in life duration. Previous findings suggest that, for poor health states, longer durations are preferred to shorter durations up to some threshold or maximum endurable time (MET), and shorter durations are preferred to longer ones after that threshold. METHODS: Monotonicity in duration is tested through 2 ordinal tasks: choices and rankings. A convenience sample (n = 90) was recruited in a series of experimental sessions in which participants had to rank-order health episodes and to choose between them, presented in pairs. Health episodes result from the combination of 7 EQ-5D-3L health states and 5 durations. Monotonicity is tested comparing the percentage rate of participants whose preferences were monotonic with the percentage of participants with nonmonotonic preferences for each health state. In addition, to test the existence of preference reversals, we analyze the fraction of people who switch their preference from rankings to choices. RESULTS: Monotonicity is frequently violated across the 7 EQ-5D health states. Preference patterns for individuals describe violations ranging from almost 49% with choices to about 71% with rankings. Analysis performed by separate states shows that the mean rates of violations with choices and ranking are about 22% and 34%, respectively. We also find new evidence of preference reversals and some evidence-though scarce-of transitivity violations in choices. CONCLUSIONS: Our results show that there is a medium range of health states for which preferences are nonmonotonic. These findings support previous evidence on MET preferences and introduce a new "choice-ranking" preference reversal. It seems that the use of 2 tasks with a similar response scale may make preference reversals less substantial, although it remains important and systematic. HIGHLIGHTS: Two procedures based on ordinal comparisons are used to elicit preferences: direct choices and rankings. Our study reports significant rates of nonmonotonic preferences (or maximum endurable time [MET]-type preferences) for different combinations of durations and EQ-5D health states.Analysis for separate health states shows that the mean rates of nonmonotonicity range from 22% (choices) to 34% (rankings), but within-subject analysis shows that nonmonotonicity is even higher, ranging from 49% (choices) to 71% (rankings). These violations challenge the validity of multiplicative QALY models.We find that the MET phenomenon may affect particularly those EQ-5D health states that are in the middle of the severity scale and not so much the extreme health states (i.e., very mild and very severe states).We find new evidence of preference reversals even using 2 procedures of a similar (ordinal) nature. Percentage rates of preference reversals range from 1.5% to 33%. We also find some (although scarce) evidence on violations of transitivity.

Pre- and intra-operative prognostic factors of facial nerve function in cerebellopontine angle surgery.

PURPOSE: The study assesses whether pre- and intraoperative factors linked to electromyography and direct electrical stimulation (DES) of facial nerve can predict facial nerve function in the short- (12 days) and long-term (1 year) after cerebellopontine angle (CPA) tumor resection. METHODS: 157 patients who underwent surgical resection of CPA tumors with facial nerve monitoring. Pre-operative factors (age, tumor size, pure tone average), surgical time and intra-operative parameters regarding facial function, minimum stimulation threshold (MST), compound muscle action potential (CMAP) and the difference between proximal and distal CMAP (DPDC) were evaluated. RESULTS: A correlation between tumor size, MST, CMAP and facial function in both short and long term was found. A higher grade of immediate facial paralysis corresponded to a higher risk of poor outcome after one year. A postoperative House-Brackmann (HB) score of V or VI was correlated with poor outcome in 88.8% and 93.8% of cases. A risk of HB 3 or more, in the long term, was correlated with a tumor size of 20.2 mm. Using an MST of 0.1 mA, for long-term predictions, sensitivity and specificity were 0.62 (95% CI 0.46-0.75) and 0.73 (95% CI 0.61-0.82), respectively. With a CMAP cut-off < 200 µV, for long-term prediction, sensitivity was 0.73 (95% CI 0.53-0.87) and specificity 0.73 (95% CI 0.55-0.85). CONCLUSION: The assessment based on the cut-offs described increases the ability to predict facial function. Improving predictive accuracy enables surgeons to address patients' expectations and to establish an intervention timeline for planning facial reanimation.

Reference-dependent age weighting of quality-adjusted life years.

People do not only care about maximizing health gains but also about their distribution. For example, they give more weight to younger patients than older patients. This pilot study aims to investigate if age weighting is reinforced by loss aversion if young people are falling behind one's perceived 'normal' quality of life (QoL), while older people do not. We apply a person trade-off method in a large representative sample (n = 990) to estimate age weighting factors. We also measure QoL levels that individuals regard as 'normal' for different ages, serving as reference points. We observe a considerable amount of age weighting, with 20-year-old patients on average receiving 1.7 times as much weight as 80-year-old patients. Perceived 'normal' QoL rapidly decreases with age of a patient. Older people are more optimistic about what constitutes 'normal QoL' than younger people, but they express a faster decline in normal QoL due to aging. Respondents who view all improvements to be gain enlarging show the least age weighting, but loss aversion cannot explain the results. Still, one's age-related reference level is an important predictor of age weights. Given the explorative nature of this study, further studies are called for to generate more robust evidence.

¿Qué es una intervención sanitaria eficiente en España en 2020? / What is an efficient health intervention in Spain in 2020?

Hace más de 15 años que en Gaceta Sanitaria se publicó el artículo titulado «¿Qué es una tecnología sanitaria eficiente en España?». El creciente interés por fijar el precio de las nuevas tecnologías en función del valor que estas proporcionan a los sistemas de salud y la experiencia acumulada por los países de nuestro entorno hacen oportuno revisar qué es una intervención sanitaria eficiente en España en el año 2020. El análisis de coste-efectividad sigue siendo el método de referencia para maximizar los resultados en salud de la sociedad con los recursos disponibles. La interpretación de sus resultados requiere establecer unos valores de referencia que sirvan de guía sobre lo que constituye un valor razonable para el sistema sanitario. Los umbrales de eficiencia deben ser flexibles y dinámicos, y actualizarse periódicamente. Su aplicación debe estar basada en la gradualidad y la transparencia, considerando, además, otros factores que reflejen las preferencias sociales. Aunque la fijación de los umbrales corresponde a los decisores políticos, en España puede ser razonable utilizar unos valores de referencia como punto de partida que podrían estar comprendidos entre los 25.000 y los 60.000 euros por año de vida ajustado por calidad. No obstante, en la actualidad, más que la determinación de las cifras exactas de dicho umbral, la cuestión clave es si el Sistema Nacional de Salud está preparado y dispuesto a implantar un modelo de pago basado en el valor, que contribuya a lograr la gradualidad en las decisiones de financiación y, sobre todo, a mejorar la previsibilidad, la consistencia y la transparencia del proceso

Fifteen years ago, Gaceta Sanitaria published the article entitled "What is an efficient health technology in Spain?" The growing interest in setting the price of new technologies based on the value they provide to health systems and the experience accumulated by the countries in our environment make it opportune to review what constitutes an efficient health intervention in Spain in 2020. Cost-effectiveness analysis continues to be the reference method to maximize social health outcomes with the available resources. The interpretation of its results requires establishing reference values that serve as a guide on what constitutes a reasonable value for the health care system. Efficiency thresholds must be flexible and dynamic, and they need to be updated periodically. Its application should be based on and transparency, and consider other factors that reflect social preferences. Although setting thresholds is down to political decision-makers, in Spain it could be reasonable to use thresholds of 25,000 and 60,000 Euros per QALY. However, currently, in addition to determining exact figures for the threshold, the key question is whether the Spanish National Health System is able and willing to implement a payment model based on value, towards achieving gradual financing decisions and, above all, to improve the predictability, consistency and transparency of the process

[What is an efficient health intervention in Spain in 2020?] / ¿Qué es una intervención sanitaria eficiente en España en 2020?

Fifteen years ago, Gaceta Sanitaria published the article entitled "What is an efficient health technology in Spain?" The growing interest in setting the price of new technologies based on the value they provide to health systems and the experience accumulated by the countries in our environment make it opportune to review what constitutes an efficient health intervention in Spain in 2020. Cost-effectiveness analysis continues to be the reference method to maximize social health outcomes with the available resources. The interpretation of its results requires establishing reference values that serve as a guide on what constitutes a reasonable value for the health care system. Efficiency thresholds must be flexible and dynamic, and they need to be updated periodically. Its application should be based on and transparency, and consider other factors that reflect social preferences. Although setting thresholds is down to political decision-makers, in Spain it could be reasonable to use thresholds of 25,000 and 60,000 Euros per QALY. However, currently, in addition to determining exact figures for the threshold, the key question is whether the Spanish National Health System is able and willing to implement a payment model based on value, towards achieving gradual financing decisions and, above all, to improve the predictability, consistency and transparency of the process.

Exploring the relative value of end of life QALYs: Are the comparators important?

In the UK, life extending, end-of-life (EoL) treatments are an exception to standard cost-per-quality-adjusted life year (QALY) thresholds. This implies that greater value is placed on gaining these QALYs, than QALYs gained by the majority of other patient groups treated for anything else in the health system, even for other EoL contexts (such as quality of life (QoL) improvements alone). This paper reports a Person Trade-Off (PTO) study to test whether studies that find societal support for prioritising EoL life extensions can be explained by the severity, in terms of prospective QALYs loss, of the non-terminal comparator scenarios. Eight health scenarios were designed depicting i) QoL improvements for non-EoL temporary (T-QoL) and chronic (C-QoL) health problems and ii) QoL improvements and life extensions (LEs) for EoL health problems. Preferences were elicited from a quota sample of 901 Scottish respondents in 2016 using PTO techniques via Computer Assisted Personal Interview (CAPI). Our results indicate that there is little evidence to suggest that the severity of non-EoL comparator scenarios influence preferences for EoL treatments. Respondents do not appear to have a preference for EoL over non-EoL health gains; instead there is some indication that non-EoL health gains are preferred, particularly when compared to EoL-LE health gains. Comparing between QoL and life extending EoL scenarios, our results suggest QoL improvements are preferred to life extensions. Overall, results challenge current UK EoL policy which gives additional weight to EoL health gains, particularly EoL life extensions in the case of the National Institute for Health and Care Excellence (NICE).

The societal monetary value of a QALY associated with EQ-5D-3L health gains.

There is an extensive body of empirical research that focuses on the societal monetary value of a quality-adjusted life year (MVQALY). Many of these studies have found the estimates to be inversely associated with the size of the health gain, and thus not conforming to the linearity assumption imposed in the QALY model. In this study, we explore the extent to which the MVQALY varies when it is associated with different types and magnitudes of quality of life (QoL) improvements. To allow for a comprehensive assessment, we derive the MVQALY corresponding to the full spectrum of health gains defined by the EQ-5D-3L instrument. The analysis was based on a large and representative sample of the population in Spain. A discrete choice experiment and a time trade-off exercise were used to derive a value set for utilities, followed by a willingness to pay questionnaire. The data were jointly analysed using regression analyses and bootstrapping techniques. Our findings indicate that societal values for a QALY corresponding to different EQ-5D-3L health gains vary approximately between 10,000€ and 30,000€. MVQALY associated with larger improvements on QoL was found to be lower than that associated with moderate QoL gains. The potential sources of the observed non-constant MVQALY are discussed.

Sequence effects in time trade-off valuation of hypothetical health states.

Choice-based stated preference methods, such as time trade-offs (TTOs), are used to establish health state utilities informing healthcare allocation. However, little is known about the presence of (position-dependent and precedent-dependent) sequence effects in the valuation of health states, despite techniques requiring respondents to evaluate several health states in a sequence. This paper is the first to explicitly test for the presence of sequence effects in the health domain using a new explanation based on contrast effects and preference imprecision; the implication being that randomisation cannot avoid sequence effects. Six TTO questions were designed using the EQ-5D-3L descriptive system. These were grouped into two blocks of three and within each block four sequences were used. In an online survey, 1,197 Spanish respondents answered one grouping of three TTO questions. Results indicate that sequence effects can affect preferences as utilities of health states are biased downwards if preceded by a better health state and biased upwards if preceded by a worse health state. This study informs our understanding of how context effects interact with preference elicitation methods, which is essential for interpreting survey results used to inform policy.

Eliciting Health State Utilities Using Paired-Gamble Methods: The Role of the Starting Point.

BACKGROUND: Paired-gamble methods have been proposed to avoid the "certainty effect" associated with standard gamble methods. OBJECTIVE: This study examines the role of starting-point effects in paired-gamble methods. In particular, it examines how the utilities so derived vary as a function of the probabilities of the stimulus lottery. METHODS: A sample of 455 members of the Spanish general population valued 9 health states via face-to-face interviews. Subjects were randomly placed into 3 subgroups, which differed in terms of the stimulus gamble's probability. Nonparametric tests and an interval regression model were used to test if utilities change when the probability distribution is modified. RESULTS: Nonparametric tests showed that the probability of a health state being considered worse than death did not differ among subgroups. Nevertheless, changes in the stimulus gamble did produce significant differences in the distribution of utilities: the higher the probability of full health in the stimulus, the higher the utility elicited. Regression estimates support the existence of starting-point effects when the utilities are obtained under expected utility. According to the prospect theory, the conclusions depend on the reference point considered. When the reference points used are death or the health state evaluated, we observe differences among these groups. Nevertheless, when full health is used, these differences disappear. CONCLUSION: This research suggests that paired-gamble methods may also be susceptible to starting-point effects. Yet the differences are small, and they disappear when the data are analyzed using prospect theory with full health as the reference point.

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.

Peer effects in health valuation: the relation between rating of contemporaries' health and own health.

BACKGROUND: Most health valuation studies assume that individuals' health valuations do not depend on social comparisons. However, there is some evidence that this assumption is not satisfied in practice. This paper tests whether self-rated health by means of a Visual Analogue Scale (VAS) is related to how one perceives the health of one's contemporaries, while accounting for one's health as classified by the EQ-5D classification system. METHODS: In a large sample (n = 1500), representative of the general public, we use a VAS to rate respondents' own health and their assessment of their contemporaries' health. In addition, we directly ask them whether they perceive their health to be better, the same, or worse than their contemporaries, and we measure their own health according to the EQ-5D-5 L. RESULTS: We find a positive relationship between own health rating and contemporaries' health rating, after controlling for the respondents' own health as classified according to the EQ-5D. Furthermore, we observe a discrepancy between relative health vis-à-vis age peers as measured by an ordinal comparison and relative health as measured by a VAS. Finally, respondents, especially women, tended to overestimate the health of other people of their age. CONCLUSIONS: We provide evidence that people's own health rating is related to the perception of health of contemporaries. Our results indicate that knowledge about a respondent's perception of others' health is useful in explaining health state valuations.

Reducing preference reversals: The role of preference imprecision and nontransparent methods.

Preferences elicited with matching and choice usually diverge (as characterised by preference reversals), violating a basic rationality requirement, namely, procedure invariance. We report the results of an experiment that shows that preference reversals between matching (Standard Gamble in our case) and choice are reduced when the matching task is conducted using nontransparent methods. Our results suggest that techniques based on nontransparent methods are less influenced by biases (i.e., compatibility effects) than transparent methods. We also observe that imprecision of preferences influences the degree of preference reversals. The preference reversal phenomenon is less strong in subjects with more precise preferences.

Handling Data Quality Issues to Estimate the Spanish EQ-5D-5L Value Set Using a Hybrid Interval Regression Approach.

BACKGROUND: The Spanish five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) valuation study was the first to use the EuroQol Valuation Technology protocol, including composite time trade-off (C-TTO) and discrete choice experiments (DCE). In this study, its investigators noticed that some interviewers did not fully explain the C-TTO task to respondents. Evidence from a follow-up study in 2014 confirmed that when interviewers followed the protocol, the distribution of C-TTO responses widened. OBJECTIVES: To handle the data quality issues in the C-TTO responses by estimating a hybrid interval regression model to produce a Spanish EQ-5D-5L value set. METHODS: Four different models were tested. Model 0 integrated C-TTO and DCE responses in a hybrid model and models 1 to 3 altered the interpretation of the C-TTO responses: model 1 allowed for censoring of the C-TTO responses, whereas model 2 incorporated interval responses and model 3 included the interviewer-specific protocol violations. For external validation, the predictions of the four models were compared with those of the follow-up study using the Lin's concordance correlation coefficient. RESULTS: This stepwise approach to modeling C-TTO and DCE responses improved the concordance between the valuation and follow-up studies (concordance correlation coefficient: 0.948 [model 0], 0.958 [model 1], 0.952 [model 2], and 0.989 [model 3]). We recommend the estimates from model 3, because its hybrid interval regression model addresses the data quality issues found in the valuation study. CONCLUSIONS: Protocol violations may occur in any valuation study; handling them in the analysis can improve external validity. The resulting EQ-5D-5L value set (model 3) can be applied to inform Spanish health technology assessments.

Emotions and scope effects in the monetary valuation of health.

This study presents evidence on the role of emotions in the monetary evaluation of health technologies, namely, drug-eluting stents (DES) in our case. It is shown that subjects who are very afraid of having to undergo an angioplasty are: (a) less sensitive to the size of the risk reduction provided by DES and (b) willing to pay more. The lack of scope sensitivity questions the normative validity of the responses of highly emotional subjects. We provide evidence of this effect using what we call the cognitive-emotional random utility model and the responses of a face-to-face, computer-assisted personal interview survey conducted in a representative sample of the Spanish general population (n = 1663).

Risk attitudes in medical decisions for others: An experimental approach.

The aim of this paper is to investigate how risk attitudes in medical decisions for others vary across health contexts. A lab experiment was designed to elicit the risk attitudes of 257 medical and nonmedical students by assigning them the role of a physician who must decide between treatments for patients. An interval regression model was used to estimate individual coefficients of relative risk aversion, and an estimation model was used to test for the effect of type of medical decision and experimental design characteristics on elicited risk aversion. We find that (a) risk attitudes vary across different health contexts, but risk aversion prevails in all of them; (b) students enrolled in health-related degrees show a higher degree of risk aversion; and (c) real rewards for third parties (patients) make subjects less risk-averse. The results underline the importance of accounting for attitudes towards risk in medical decision making.

Improving scope sensitivity in contingent valuation: Joint and separate evaluation of health states.

We present data of a contingent valuation survey, testing the effect of evaluation mode on the monetary valuation of preventing road accidents. Half of the interviewees was asked to state their willingness to pay (WTP) to reduce the risk of having only 1 type of injury (separate evaluation, SE), and the other half of the sample was asked to state their WTP for 4 types of injuries evaluated simultaneously (joint evaluation, JE). In the SE group, we observed lack of sensitivity to scope while in the JE group WTP increased with the severity of the injury prevented. However, WTP values in this group were subject to context effects. Our results suggest that the traditional explanation of the disparity between SE and JE, namely, the so-called "evaluability," does not apply here. The paper presents new explanations based on the role of preference imprecision.

Valuation and Modeling of EQ-5D-5L Health States Using a Hybrid Approach.

BACKGROUND: The EQ-5D instrument is the most widely used preference-based health-related quality of life questionnaire in cost-effectiveness analysis of health care technologies. Recently, a version called EQ-5D-5L with 5 levels on each dimension was developed. This manuscript explores the performance of a hybrid approach for the modeling of EQ-5D-5L valuation data. METHODS: Two elicitation techniques, the composite time trade-off, and discrete choice experiments, were applied to a sample of the Spanish population (n=1000) using a computer-based questionnaire. The sampling process consisted of 2 stages: stratified sampling of geographic area, followed by systematic sampling in each area. A hybrid regression model combining composite time trade-off and discrete choice data was used to estimate the potential value sets using main effects as starting point. The comparison between the models was performed using the criteria of logical consistency, goodness of fit, and parsimony. RESULTS: Twenty-seven participants from the 1000 were removed following the exclusion criteria. The best-fitted model included 2 significant interaction terms but resulted in marginal improvements in model fit compared to the main effects model. We therefore selected the model results with main effects as a potential value set for this methodological study, based on the parsimony criteria. The results showed that the main effects hybrid model was consistent, with a range of utility values between 1 and -0.224. CONCLUSION: This paper shows the feasibility of using a hybrid approach to estimate a value set for EQ-5D-5L valuation data.

Exploring Differences between TTO and DCE in the Valuation of Health States.

There is recent interest in using discrete choice experiments (DCEs) to derive health state utility values, and results can differ from time tradeoff (TTO). Clearly, DCE is "choice based," whereas TTO is generally considered a "matching" task. We explore whether procedural adaptations to the TTO, which make the method more closely resemble a DCE, make TTO and choice converge. In particular, we test whether making the matching procedure in TTO less "transparent" to the respondent reduces disparities between TTO and DCE. We designed an interactive survey that was hosted on the Internet, and 2022 interviews were achieved in the United Kingdom in a representative sample of the population. We found a marked divergence between TTO and DCE, but this was not related to the "transparency" of the TTO procedure. We conclude that a difference in the error structure between TTO and choice and that factors other than differences in utility are affecting choices is driving the divergence. The latter has fundamental implications for the way choice data are analyzed and interpreted.