GET MORE, PAY MORE? An elaborate test of construct validity of willingness to pay per QALY estimates obtained through contingent valuation

Monetary value of health-a practical decision-making framework combining equity considerations and WTP

OBJECTIVE

We estimate the first monetary value of a health gain in Croatia to inform the debate about the appropriate "demand-side" cost-effectiveness thresholds in Croatia but also Central and Eastern Europe, where such debates are still uncommon. We test the empirical support for two equity considerations: age and severity operationalized as proportional shortfall (PS), and propose a pragmatic framework for combining equity considerations with the monetary value of health into a single threshold.

METHODS

We used the contingent valuation method to elicit the willingness to pay per Quality-Adjusted Life Year (QALY) in Croatia, using a representative sample of the population (N = 1,500, online survey). 29 EQ-5D health states were valued using payment scales and open-ended question as payment vehicles. To test the hypotheses, we used both parametric tests and non-parametric tests. Multilinear regression was employed to test the theoretical validity of the results.

RESULTS

The monetary value of a health gain in Croatia is equivalent to 1.15 of GDP per capita (equaling €17,000). Age of patients seems to be an important equity-related characteristic. The WTP per QALY in the age-neutral risk group (€11,900) was nearly equivalent to the WTP per QALY in the adult (neutral) risk group (€11,700) but lower by 16% compared to the WTP per QALY estimated in children (€14,200; p = 0.00). WTP estimates are theoretically valid and to, a small degree, scale sensitive. There is a positive association between the level of proportional shortfall and willingness to pay. To increase the usefulness of our results for the policy-makers, we combine the elicited preferences into a single decision-making framework and construct several cost-effectiveness thresholds based on willingness to pay and equity-related preferences. Based on empirical results, cost-effectiveness thresholds could range up to €20,308 for the most severe health conditions in children or could be lowered to €16,777 for less severe health conditions.

DISCUSSION

In Central and Eastern Europe, in spite of a growing understanding of the importance of further developing value-based assessment frameworks there has been very little empirical research to guide, inform and promote this development. Countries in this region use mainly GDP-based thresholds without empirical evidence to support such important decisions. This may lead to thresholds that are too high, with detrimental consequence for the pricing and reimbursement systems.

A systematic review on the direct approach to elicit the demand-side cost-effectiveness threshold: Implications for low- and middle-income countries

Several literature review studies have been conducted on cost-effectiveness threshold values. However, only a few are systematic literature reviews, and most did not investigate the different methods, especially in-depth reviews of directly eliciting WTP per QALY. Our study aimed to 1) describe the different direct approach methods to elicit WTP/QALY; 2) investigate factors that contribute the most to the level of WTP/QALY value; and 3) investigate the relation between the value of WTP/QALY and GDP per capita and give some recommendations on feasible methods for eliciting WTP/QALY in low- and middle-income countries (LMICs). A systematic review concerning select studies estimating WTP/QALY from a direct approach was carried out in seven databases, with a cut off date of 03/2022. The conversion of monetary values into 2021 international dollars (i$) was performed via CPI and PPP indexes. The influential factors were evaluated with Bayesian model averaging. Criteria for recommendation for feasible methods in LMICs are made based on empirical evidence from the systematic review and given the resource limitation in LMICs. A total of 12,196 records were identified; 64 articles were included for full-text review. The WTP/QALY method and values varied widely across countries with a median WTP/QALY value of i$16,647.6 and WTP/QALY per GDP per capita of 0.53. A total of 11 factors were most influential, in which the discrete-choice experiment method had a posterior probability of 100%. Methods for deriving WTP/QALY vary largely across studies. Eleven influential factors contribute most to the level of values of WTP/QALY, in which the discrete-choice experiment method was the greatest affected. We also found that in most countries, values for WTP/QALY were below 1 x GDP per capita. Some important principles are addressed related to what LMICs may be concerned with when conducting studies to estimate WTP/QALY.

VOLY: The Monetary Value of a Life-Year at the End of Patients' Lives

OBJECTIVE

We explored the monetary value of the end-of-life (EoL) health gains, that is, the value of a life-year (VOLY) gained at the end of a patient's life in Croatia. We tested whether the nature of the illness under valuation (cancer and/or rare disease) is a factor in the valuation of EoL-VOLYs. The aim was for our results to contribute to the health and longevity valuation literature and more particularly to the debate on the appropriate cost-effectiveness threshold for EoL treatments as well as to provide input into the debate on the justifiability of a cancer and/or a rare disease premium when evaluating therapies.

METHODS

A contingent valuation was conducted in an online survey using a representative sample of the Croatian population (n = 1500) to calculate the willingness to pay for gains in the remaining life expectancy at the EoL, from the social-inclusive-individual perspective, using payment scales and an open-ended payment vehicle. Our approach mimics the actual decision-making problem of deciding whether to reimburse therapies targeting EoL conditions such as metastatic cancer whose main purpose is to extend life (and not add quality to life).

RESULTS

Average EoL-VOLY across all scenarios was estimated at €67,000 (median €40,000). In scenarios that offered respondents 1 full year of life extension, EoL-VOLY was estimated at €33,000 (median €22,000). Our results show that the type of illness is irrelevant for EoL-VOLY evaluations.

CONCLUSIONS

The pressure to reimburse expensive therapies targeting EoL conditions will continue to increase. Delivering "value for money" in healthcare, both in countries with relatively higher and lower budget restrictions, requires the valuation of different types of health gains, which should, in turn, affect our ability to evaluate their cost effectiveness.

A Decade of Health Innovation: The Impact of New Medicines on Patient Health and the Implications for NICE's Size of Benefit Multiplier

OBJECTIVES

This study aimed to estimate the incremental health benefits of pharmaceutical innovations approved between 2011 and 2021 and the share that would surpass the National Institute for Health and Care Excellence (NICE) "size of benefit" decision weight thresholds.

METHODS

We identified all US-approved drugs between 2011 and 2021. Health benefits, in terms of quality-adjusted life-years (QALYs) for each treatment, were extracted from published cost-effectiveness analyses. Summary statistics by therapeutic area and cell/gene therapy status identified the treatments with the largest QALY gains.

RESULTS

The Food and Drug Administration approved 483 new therapies between 2011 and 2021 and of these 252 had a published cost-effectiveness analysis meeting our inclusion criteria. The average incremental health benefits produced by these treatments were 1.04 QALYs (SD = 2.00) relative to standard of care, with wide variation by therapeutic area. Pulmonary and ophthalmologic therapies produced the highest health benefits with 1.47 (SD = 2.17, n = 13) and 1.41 QALYs gained (SD = 3.53, n = 7), respectively; anesthesiology and urology had the lowest gains (< 0.1 QALYs). Cell and gene therapies produced an average health benefit that was 4 times greater than noncell and gene therapies (4.13 vs 0.96). Among the top treatments in terms of incremental QALYs gained, half (10 of 20) were oncology therapies. Three of 252 treatments (1.2%) met NICE's threshold for a "size of benefit" multiplier.

CONCLUSIONS

Treatments for rare disease, oncology, and cell and gene therapies produced some of the highest level of health innovation relative to previous standard of care, but few therapies would have qualified for NICE's "size of benefit" multiplier as currently constructed.

Willingness to Pay for One Additional Quality Adjusted Life Year: A Population Based Survey from China

OBJECTIVE

The aim of this study was to estimate the population's willingness to pay (WTP) for an additional quality-adjusted life-year (QALY) in China.

METHODS

The WTP for an additional QALY (WTP/Q) was estimated using a contingent valuation survey with quota sampling and snowball sampling, using a pre-designed questionnaire with 18 hypothetical scenarios. The change in health state was depicted by the EQ-5D-5L. The questionnaires were completed by telephone and face-to-face interviews. Two-part regression models were used to test validity and how different factors affect WTP/Q.

RESULTS

A total of 2008 people participated in this survey and provided 3265 WTP responses for further analysis. The average WTP/Q for the entire sample is 113,120 Renminbi (RMB) (USD 16,884), which is 1.75 times the gross domestic product (GDP) per capita. For the quality-of-life improvement scenarios, the mean WTP/Q is RMB 78,907 (USD 11,777, 1.22 times GDP per capita), which is significantly lower than the life extension scenarios (RMB 177,761, USD 26,531, 2.76 times GDP per capita). Age was found to be negatively related to positive WTP. Educational level was positively related to the probability of reporting positive WTP and the level of WTP/Q. Although the EQ-5D-5L utility scores of respondents did not prove to be statistically significant determinants of WTP/Q, the two dimensions of EQ-5D-5L, pain/discomfort and anxiety/depression, had an impact on WTP/Q. In addition, WTP/Q was higher when the health outcome had a 50% probability of occurring than when the health outcome was 100% certain. WTP/Q was higher when a lower health gain was presented to the respondent.

CONCLUSION

This study provides empirical evidence of the monetary value of an additional QALY from a sample of the Chinese population. In addition, a higher threshold for end-of-life therapies should be considered.

Willingness to pay for health gains from an international integrated early warning system for infectious disease outbreaks

Recently, due to the corona virus outbreak, pandemics and their effects have been at the forefront of the research agenda. However, estimates of the perceived value of early warning systems (EWSs) for identifying, containing, and mitigating outbreaks remain scarce. This paper aims to show how potential health gains due to an international EWS might be valued. This paper reports on a study into willingness to pay (WTP) in six European countries for health gains due to an EWS. The context in which health is gained, those affected, and the reduction in risk of contracting the disease generated by the EWS are varied across seven scenarios. Using linear regression, we analyse this 'augmented' willingness to pay for a QALY (WTP-Q) for each of the scenarios, where 'augmented' refers to the possible inclusion of context specific elements of value, such as feelings of safety. An initial WTP-Q estimate for the basic scenario is €17,400. This can be interpreted as a threshold for investment per QALY into an EWS. Overall, WTP estimates move in the expected directions (e.g. higher risk reduction leads to higher WTP). However, changes in respondents' WTP for reductions in risk were not proportional to the magnitude of the change in risk reduction. This study provided estimates of the monetary value of health gains in the context of a pandemic under seven scenarios which differ in terms of outcome, risk reduction and those affected. It also highlights the importance of future research into optimal ways of eliciting thresholds for investments in public health interventions.

The demand for a COVID-19 vaccine

Taking willingness to pay as primitive, this paper establishes an analytical framework for demand estimation, where the estimator is robust to endogeneity of price. Applying the framework, this paper then estimates demand functions for a COVID-19 vaccine and compute the consumer surplus in both China and the UAE. We find that the price elasticities of demand are mostly greater than one in both countries. An elastic demand suggests subsidy is likely to be successful in promoting vaccination. The consumer surplus is sizeable, around 58 billion US$ in China and 646 million US$ in the UAE. The figures can inform policymakers in assessing their vaccine programs.

Estimating the range of incremental cost-effectiveness thresholds for healthcare based on willingness to pay and GDP per capita: A systematic review

Background

Decision-making in healthcare policy involves assessing both costs and benefits. In determining the cost-effectiveness (CE) threshold, willingness to pay (WTP) per quality-adjusted life year (QALY), GDP per capita, and other factors are important. However, the relationship between WTP/QALY or GDP per capita and the CE threshold is unclear. It is important to clarify the relationship between WTP/QALY and GDP to provide a clear basis for setting the CE threshold.

Objective

The purpose of this study was to compare WTP/QALY and GDP per capita, and to develop a new CE threshold range based on WTP using GDP per capita. The relationship between WTP/QALY and healthy life expectancy (HALE) was also investigated.

Methods

We searched MEDLINE, EMBASE and Web of Science from 1980/01/01 to 2020/12/31 using the following selection criteria (latest search: Dec 2021):1, studies that estimated WTP/QALY; 2, the general population was surveyed; 3, the article was in English. From the collected articles, we obtained average values of WTP/QALY for various countries and compared WTP/QALY with GDP per capita. The correlation between WTP/QALY and HALE was also examined.

Results

We identified 20 papers from 17 countries. Comparison of mean WTP/QALY values with GDP per capita showed that most WTP/QALY values were in the range of 0.5–1.5 times GDP per capita, though the median values were less than 0.5 times. Comparison of WTP/QALY with HALE showed a statistically significant positive correlation when Taiwan was excluded as an outlier.

Conclusions

Our results suggest a CE threshold range of 0.5–1.5 times GDP per capita is appropriate but lower than the WHO-recommended range of 1–3 times. The correlation between WTP/QALY and HALE suggests that investment in healthcare is reflected in an increased healthy life expectancy. Since WTP is based on consumer preferences, this range could be used to set a generally acceptable criterion.

Willingness to pay for a quality-adjusted life year: a systematic review with meta-regression

The use of a threshold for cost-utility studies is of major importance to health authorities for making the best allocation decisions for limited resources. Regarding the increasing number of studies worldwide that seek to establish a value for a quality-adjusted life year (QALY), it is necessary to review these studies to provide a global insight into the literature. A systematic review on willingness to pay (WTP) studies focusing on QALY was conducted in eight databases up to June 26, 2020. From a total of 9991 entries, 39 studies were selected, and 511 observations were extracted for the meta-analysis using the ordinary least squares method. The results showed a predicted mean empirical value of $52,619.39 (95% CI 49,952.59; 55,286.19) per QALY in US dollars for 2018. A 1% increase in income led to an increase of 0.6% in the WTP value, while a 1-year increase in respondent age led to a decrease of 3.3% in the WTP value. Sex, education level and employment status had significant effects on WTP. Compared to face-to-face interviews, surveys conducted by the internet or telephone were more likely to have a significantly higher value of WTP per QALY, while out-of-pocket payment tended to lower the value. The prediction made for the province of Quebec, Canada, provided a QALY value of approximately USD $98,450 (CAD $127,985), which is about 2.3 times its gross domestic product (GDP) per capita in 2018. This study is consistent with the extant literature and will be useful for countries that do not yet have a preference-based survey for the value of a QALY.

Did the COVID-19 pandemic change the willingness to pay for an early warning system for infectious diseases in Europe?

The COVID-19 pandemic highlights the need for effective infectious disease outbreak prevention. This could entail installing an integrated, international early warning system, aiming to contain and mitigate infectious diseases outbreaks. The amount of resources governments should spend on such preventive measures can be informed by the value citizens attach to such a system. This was already recognized in 2018, when a contingent valuation willingness to pay (WTP) experiment was fielded, eliciting the WTP for such a system in six European countries. We replicated that experiment in the spring of 2020 to test whether and how WTP had changed during an actual pandemic (COVID-19), taking into account differences in infection rates and stringency of measures by government between countries. Overall, we found significant increases in WTP between the two time points, with mean WTP for an early warning system increasing by about 50% (median 30%), from around €20 to €30 per month. However, there were marked differences between countries and subpopulations, and changes were only partially explained by COVID-19 burden. We discuss possible explanations for and implication of our findings.

The price of curing cancer

Background

Health care systems around the world struggle with high prices for new cancer drugs. The purpose of this study was to conduct a gedankenexperiment and calculate how much health expenditures would change if a cure for cancer through pharmaceutical treatment were made available. The cancer cure was conceived to eliminate both cancer deaths and the underlying morbidity burden of cancer. Furthermore, the cure was hypothesized to arrive in incremental steps but at infinitesimally small time intervals (resulting, effectively, in an immediate cure).

Methods

The analysis used secondary data and was conducted from the viewpoint of the German social health insurance. As its underlying method, it used a cause-elimination life-table approach. To account for the age distribution of the population, the study weighted age-specific increases in remaining life expectancy by age-specific population sizes. It considered drug acquisition costs as well as savings and life extension costs from eliminating cancer. All cancer drugs that underwent a mandatory early benefit assessment in Germany between 2011 and 2015/16 and were granted an added benefit were included. Data on age- and gender-specific probabilities of survival, population sizes, causes of death, and health expenditures, as well as data on cancer costs were taken from the German Federal Office of Statistics and the German Federal Social Insurance Office.

Results

Based on the cause-elimination life-table approach and accounting for the age structure of the German population, curing cancer in Germany yields an increase in average remaining life expectancy by 2.66 life years. Based on the current incremental cost-effectiveness ratio of new cancer drugs, which is on average €101,493 per life year gained (€39,751/0.39 life years), the German social health insurance would need to pay €280,497 per insuree to eliminate cancer. Dividing this figure by current average remaining lifetime health expenditures yields a ratio of 2.07, which represents a multiplier of current health expenditures.

Conclusions

Eliminating cancer at current price levels would more than triple total health expenditures in Germany. As the current price of a cure requires a drastic reduction of non-health consumption, it appears that current prices for cancer drugs already on the market (i.e., small steps towards a cure) need careful reconsideration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-07327-x.

Willingness to pay vs lottery equivalent to value the impact of alcohol misuse on quality of life

OBJECTIVES

To estimate the impact of alcohol disorders using lottery equivalent (LE) and willingness to pay (WTP) methods and compute the WTP for a QALY (WTP-Q) derived from these values.

METHODS

Two samples of 300 people valued nine states of alcohol misuse. LE and WTP were used in sample 1 and 2, respectively. The ability to discriminate between methods was tested. Regression models were performed to estimate the preference weights of dimensions. Several values of WTP-Q were obtained by combining the estimated values from both samples.

RESULTS

LE and WTP produce the same ranking of states but LE is more sensitive. The estimated impact of the nine states ranges between 0.91 and 0.22 QALYs, and the WTP for avoiding them ranges between €10,444 and €4132. WTP-Q varies between €11,473 and €19,092 when the mean values of the states are used. The WTP-Q tends to decrease with the severity.

CONCLUSIONS

Although LE and WTP provide values for cost-utility and cost-benefit analyses, respectively, LE seems to be preferable for measuring the impact of alcohol disorders. As the lower sensitivity of WTP seems to explain a WTP-Q decrease with severity, more research is needed before recommending the use of different WTP-Q values.

A Systematic Review of Demand-Side Methods of Estimating the Societal Monetary Value of Health Gain

OBJECTIVES

Although many reviews of the literature on cost-effectiveness thresholds (CETs) exist, the availability of new studies and the absence of a fully comprehensive analysis warrant a new review. This study systematically reviews demand-side methods for estimating the societal monetary value of health gain.

METHODS

Several electronic databases were searched from inception to October 2019. To be included, a study had to be an original article in any language, with a clearly described method for estimating the societal monetary values of health gain and with all estimated values reported. Estimates were converted to US dollars ($), using purchasing power parity (PPP) exchange rates and the gross domestic product (GDP) per capita (2019).

RESULTS

We included 53 studies; 45 used direct approach and 8 used indirect approach. Median estimates from the direct approach were PPP$ 24 942 (range 554-1 301 912) per quality-adjusted life-year (QALY), which were typically 0.53 (range 0.02-24.08) GDP per capita. Median estimates using the indirect approach were PPP$ 310 051 (range 36 402-7 574 870) per QALY, which accounted for 7.87 (range 0.68-116.95) GDP per capita.

CONCLUSIONS

Our review found that the societal values of health gain or CETs were less than GDP per capita. The great variety in methods and estimates suggests that a more standardized and internationally agreed methodology for estimating CET is warranted. Multiple CETs may have a role when QALYs are not equally valued from a societal perspective (eg, QALYs accruing to people near death compared with equivalent QALYs to others).

The value of health-Empirical issues when estimating the monetary value of a quality-adjusted life year based on well-being data

Decisions on interventions or policy alternatives affecting health can be informed by economic evaluations, like cost-benefit or cost-utility analyses. In this context, there is a need for valid estimates of the monetary equivalent value of health (gains), which are often expressed in € per quality-adjusted life years (QALYs). Obtaining such estimates remains methodologically challenging, with a recent addition to the health economists' toolbox, which is based on well-being data: The well-being valuation approach. Using general population panel data from Germany, we put this approach to the test by investigating several empirical and conceptual challenges, such as the appropriate functional specification of income utility, the choice of health utility tariffs, or the health state dependence of consumption utility. Depending on specification, the bulk of estimated € per QALY values ranged from €20,000-60,000, with certain specifications leading to more considerable deviations, underlining persistent practical challenges when applying the well-being valuation methodology to health and QALYs. Based on our findings, we formulate recommendations for future research and applications.

Willingness to Pay for Health-Related Quality of Life Gains in Relation to Disease Severity and the Age of Patients

OBJECTIVES

Decision-making frameworks that draw on economic evaluations increasingly use equity weights to facilitate a more equitable and fair allocation of healthcare resources. These weights can be attached to health gains or reflected in the monetary threshold against which the incremental cost-effectiveness ratios of (new) health technologies are evaluated. Currently applied weights are based on different definitions of disease severity and do not account for age-related preferences in society. However, age has been shown to be an important equity-relevant characteristic. This study examines the willingness to pay (WTP) for health-related quality of life (QOL) gains in relation to the disease severity and age of patients, and the outcome of the disease.

METHODS

We obtained WTP estimates by applying contingent-valuation tasks in a representative sample of the public in The Netherlands (n = 2023). We applied random-effects generalized least squares regression models to estimate the effect of patients' disease severity and age, size of QOL gains, disease outcome (full recovery/death 1 year after falling ill), and respondent characteristics on the WTP.

RESULTS

Respondents' WTP was higher for more severely ill and younger patients and for larger-sized QOL gains, but lower for patients who died. However, the relations were nonlinear and context dependent. Respondents with a lower age, who were male, had a higher household income, and a higher QOL stated a higher WTP for QOL gains.

CONCLUSIONS

Our results suggest that-if the aim is to align resource-allocation decisions in healthcare with societal preferences-currently applied equity weights do not suffice.

Comparing the monetary value of a quality-adjusted life year from the payment card and the open-ended format

BACKGROUND

The payment card (PC) format and the open-ended (OE) format are common methods in eliciting willingness-to-pay (WTP) of one additional quality-adjusted life year (QALY). The aim of this research is to compare these two formats in eliciting the monetary value of a QALY.

METHODS

A contingent valuation survey was carried out using a pre-designed questionnaire with various hypothetical scenarios. The difference between the PC and the OE formats was evaluated by a two-sample equality test. Furthermore, generalized linear models were carried out to control observed heterogeneity and to test theoretical validity.

RESULTS

In total, 461 individuals were involved, among whom 235 (51%) answered the PC question, while 226 (49%) answered the OE question. Excluding zero response, the mean WTP values of these two formats for different scenarios varied dramatically, which was from 13,278 to 280,177 RMB for the PC, 18,119 to 620,913 RMB for the OE. The OE format tended to elicit lower values for less serious condition and higher values for more serious condition. However, equality test of mean and median demonstrated insignificant difference of these two formats for all scenarios. For both OE and PC format, most variables were found to have significant effect on the value of WTP/QALY. Moreover, joint estimation indicated a statistically significant positive effect on the OE results. Further analysis demonstrated that the imbalanced zero response distribution caused the main difference of these two formats.

CONCLUSIONS

This research indicated insignificantly different WTP/QALY estimates of the PC format and OE format with the grouped data whereas significantly higher estimates of the OE format from the pooled data. These two formats were found to be valid. More research about the difference and the validity of various WTP eliciting methods would be recommended for a robust estimation of WTP/QALY.

Sample restrictions and the elicitation of a constant willingness to pay per quality adjusted life year

It is well established that the underlying theoretical assumptions needed to obtain a constant proportional trade-off between a quality adjusted life year (QALY) and willingness to pay (WTP) are restrictive and often empirically violated. In this paper, we set out to investigate whether the proportionality conditions (in terms of scope insensitivity and severity independence) can be satisfied when data is restricted to include only respondents who pass certain consistency criteria. We hypothesize that the more we restrict the data, the better the compliance with the requirement of constant proportional trade-off between WTP and QALY. We revisit the Danish data from the European Value of a QALY survey eliciting individual WTP for a QALY (WTP-Q). Using a "chained approach" respondents were first asked to value a specified health state using the standard gamble (SG) or the time-trade-off (TTO) approach and subsequently asked their WTP for QALY gains of 0.05 and 0.1 (tailored according to the respondent's SG/TTO valuation). Analyzing the impact of the different exclusion criteria on the two proportionality conditions, we find strong evidence against a constant WTP-Q. Restricting our data to include only respondents who pass the most stringent consistency criteria does not impact on the performance of the proportionality conditions for WTP-Q.

A systematic review and meta-regression of studies eliciting willingness-to-pay per quality-adjusted life year in the general population

OBJECTIVES

From the demand-side perspective, the monetary value of one additional quality-adjusted life year (QALY) is estimated as willingness-to-pay per QALY (WTPQ). This study aims to summarize the methods and contexts of elicitation of willingness-to-pay per quality-adjusted life year (WTPQ) in the general population and to investigate the heterogeneity of WTPQ estimates.

METHODS

Meta-regression analysis was conducted using Comprehensive Meta-Analysis Software. Sensitivity analyses were undertaken by replacing the lowest and highest 5% and 2.5% of WTPQ by percentiles.

RESULTS

33 studies with 102 WTPQ estimates were included. The overall mean and median WTPQ estimates are $1,280,002 and $44,072, respectively. The meta-regressions demonstrated that types of health gain (quality of life or life length) and certainty of health outcomes are statistically significant factors. Furthermore, compared with online interviews, face-to-face interviews tend to yield lower WTPQ. Moreover, the declining trend of QALY gains and positive effect with statistical significance of the sample age were also noticed.

CONCLUSION

For valid and representative values of WTPQ, future researchers should therefore take into consideration various scenarios and investigate both health gain with certainty and uncertainty, health gain from both life length and quality of life, and different size of QALY gains.

A Contingent Valuation Study for Eliciting a Monetary Value of a Quality-Adjusted Life-Year in the General Greek Population

OBJECTIVES

To elicit a willingness-to-pay (WTP) per quality-adjusted life-year (QALY) estimate for the general Greek population and assess the impact of individuals' socio-demographic characteristics and motives on this estimate.

METHODS

A telephone-based survey was carried out employing a representative sample of the general Greek population (n = 1342). A computer-assisted telephone-interview method was adopted to ensure random sampling. A total of 528 participants reported a WTP value for a utility improvement from their current health to perfect health. Those individuals' motives were assessed through predefined statements. Test-retest reliability was assessed using intraclass correlation coefficient (ICC). Multiple linear regression (MLR) and one-way analysis of variance (ANOVA) tests were conducted to assess the effect of socioeconomic/demographic determinants and motive statements, respectively, on WTP/QALY. MLR was re-estimated considering as dependent variable the WTP/QALY estimate calculated for participants: (1) stating a WTP value ≤ their household income and (2) presenting higher certainty regarding stated WTP value (sensitivity analysis).

RESULTS

Analysis revealed good reliability for WTP/QALY estimates and motive statements (ICC values > 0.8). Mean WTP/QALY was €26 280. The respective 5% trimmed value was €14 862. Being a student and household income affected WTP/QALY. Sensitivity analysis did not produce markedly different WTP/QALY predictors, implying the robustness of results, irrespective of the participant group considered. Individuals who indicated the inability to cover basic family needs or pay tax claims as motives reported lower WTP/QALY values compared with those not viewing these aspects as motives.

CONCLUSIONS

Findings confirm that the World Health Organization's criterion used currently in Greek cost-effectiveness studies is not unreasonable. Additional research is essential to further explore WTP/QALY estimates in the Greek setting and facilitate informed decision making.

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.

Value of a QALY and VSI estimated with the chained approach

The value of a quality-adjusted life-year (QALY) and the value of a statistical injury (VSI) are important measures within health economics and transport economics. Several studies have, therefore, estimated people's willingness to pay (WTP) for these estimates, but most results show scale insensitivity. The 'original' chained approach (CA) is a method developed to mitigate this problem by combining the contingent valuation (CV) with standard gamble (SG). In contrast to the version of the CA applied by the previous research of the WTP for a QALY, the original version allows the value of major health gains to be estimated without having the respondents express their WTP directly. The objective of this study was to estimate the value of a QALY and VSI in the context of non-fatal road traffic accidents using the original CA to test if the approach, applied to a wide range of health gains, is able to derive valid estimates and a constant value of a QALY which the previous research has not been able to show. Data were collected from a total of 800 individuals in the Swedish adult general population using two web-based questionnaires. The values of a QALY based on trimmed estimates were close to constant at €300,000 irrespective of the size of the QALY gain. The study shows that the original CA method may be a valid method to estimate the value of a QALY and VSI for major health losses. It also supports the use of a higher threshold value for a QALY than that which is currently applied by several health technology assessment agencies in different countries.

Evaluation of willingness to pay per quality-adjusted life year for a cure: A contingent valuation method using a scenario-based survey

Cost-effectiveness is 1 of the most important factors in medicine reimbursement, and social willingness to pay (WTP) can provide evidence for the threshold of cost-effectiveness analysis. Recently, the concept of curative medicines has been introduced, so it is necessary to study their cost-effectiveness. This study aimed to estimate WTP per quality-adjusted life year (QALY) for a cure in the Korean general population.A total of 507 people from the general population, proportionally assigned by sex, age, and region, participated in face-to-face interviews. The contingent valuation survey was conducted with scenarios involving 4 EuroQol-5 dimensions (EQ-5D) with different health statuses. We assumed a treatment that moved the health status of each scenario to perfect health. WTP for 1 year of treatment was derived using a double-bounded format followed by open-ended answers. In the cure scenario, the post-treatment effect continued for a lifetime; in the non-cure scenario, the effect instantly stopped when treatment was terminated. Additionally, prolonged treatment effects lasting 5 and 10 years were added. To identify the factors influencing WTP, a multi-level analysis was performed.WTP per QALY for the non-cure scenario was KRW 15 million/QALY. For the cure scenario, WTP was 2.3 times higher (KRW 35 million/QALY) than in the non-cure scenario. The results for the prolonged treatment effect scenarios were KRW 22 million/QALY and KRW 27 million/QALY, which are 1.4 and 1.8 times higher than the non-cure scenario, respectively. In all scenarios, the statistically significant factors affecting WTP per QALY were higher education, higher household income, and healthcare provider.This study revealed that WTP for a cure treatment was higher than that for non-cure; this higher WTP should be considered in future decision-making regarding curative treatments.

Estimating a constant WTP for a QALY-a mission impossible?

Economic evaluations are an important input to decision-making and priority-setting in the health care sector. Measuring preferences for health improvements, as the demand-side value (willingness to pay) of gaining a quality-adjusted life year (QALY), is one relevant component in the interpretation of the results from health economic evaluations. Our article addresses whether willingness to pay for a QALY (WTP-Q) is sensitive to the size of the health differences and the probability for improvement. We use data from a contingent valuation survey based on 1400 respondents conducted in the spring of 2014. The results show that the expectation of sensitivity to scope, or higher WTP to the larger expected quality of life improvement, is not supported. We find WTP-Q values that conform reasonably well to previous studies in Sweden.

Eliciting the Monetary Value of a Quality-Adjusted Life Year in a Greek Outpatient Department in Times of Economic Austerity

BACKGROUND AND OBJECTIVE

Contingent valuation is widely used to determine individuals' willingness to pay (WTP) for a health gain. Our study aimed to elicit an empirical estimate of the monetary value of a quality-adjusted life year (QALY) in a Greek outpatient setting in times of economic austerity and assess the impact of patients' characteristics on their valuations.

METHODS

We used a questionnaire as a survey tool to determine the maximum WTP for a health gain of a hypothetical therapy and to evaluate patients' health-related quality of life (EuroQoL-5D-3L) and demographic and socioeconomic characteristics. EuroQoL tariffs were used to estimate health utilities. Mean WTP values were computed and ordinary least squares regressions performed on transformed Box-Cox and logarithmic dependent WTP per QALY variables to remedy observed skewness problems.

RESULTS

Analyses were performed for 167 patients with utility values less than unity. Mean WTP per QALY reported was similar for both payment vehicles examined: payments made out-of-pocket (€2629) and payments made through new tax imposition (€2407). Regression results showed that higher net monthly family income was associated with higher WTP per QALY for both payment vehicles. Moreover, the presence of a chronic condition and higher level of education were associated with higher out-of-pocket WTP per QALY and WTP per QALY through taxes, respectively.

CONCLUSION

The very low WTP per QALY estimates could be explained by the recent severe economic depression and austerity in Greece. In fact, family income was found to be a significant predictor of WTP per QALY. Since these estimates deviate significantly from the cost-effectiveness thresholds still employed in economic evaluations in this country, research should be undertaken promptly to further examine this important issue using a nationwide representative sample of the general population along with WTP and other methodologies.

The impact of the design of payment scales on the willingness to pay for health gains

The questionnaire format applied in a CV study represents the way in which the WTP estimates are obtained. Payment scales are often used in CV studies as the questionnaire format of choice. The study summarized here analyzes the impact of the design of two payment scales (PS) on the monetary value of QALY gains. The scales differed in terms of their end-points, mid points, and coarseness. We judged the performance of the two PS against several indicators: the average WTP per QALY estimates, post-estimation uncertainty levels, the existence of mid-point concentration, and the dependency on end-points. Our results show that PS design influences respondents' WTP values. The results also suggest that a more detailed scale with a more realistic range may help respondents to elicit values closer to their "true" WTP values, hence produce higher-quality outcomes. Further research and pretesting strategies are suggested to explore and minimize the effects of PS design on WTP estimates, which may ultimately increase the quality of WTP estimates.

Exploring a new method for deriving the monetary value of a QALY

Several studies have sought to determine the monetary value of health gains expressed as quality adjusted life years (QALYs) gained, predominantly using willingness to pay approaches. However, willingness to pay has a number of recognized problems, most notably its insensitivity to scope. This paper presents an alternative approach to estimate the monetary value of a QALY, which is based on the time trade-off method. Moreover, it presents the results of an online study conducted in the Netherlands exploring the feasibility of this novel approach. The results seem promising, but also highlight a number of methodological problems with this approach, most notably nontrading and the elicitation of negative values. Additional research is necessary to try to overcome these problems and to determine the potential of this new approach.

Modelling Nonlinearities and Reference Dependence in General Practitioners' Income Preferences

This paper tests for the existence of nonlinearity and reference dependence in income preferences for general practitioners. Confirming the theory of reference dependent utility within the context of a discrete choice experiment, we find that losses loom larger than gains in income for Norwegian general practitioners, i.e. they value losses from their current income level around three times higher than the equivalent gains. Our results are validated by comparison with equivalent contingent valuation values for marginal willingness to pay and marginal willingness to accept compensation for changes in job characteristics. Physicians' income preferences determine the effectiveness of 'pay for performance' and other incentive schemes. Our results may explain the relative ineffectiveness of financial incentive schemes that rely on increasing physicians' incomes. Copyright © 2015 John Wiley & Sons, Ltd.

On the Estimation of the Cost-Effectiveness Threshold: Why, What, How?

BACKGROUND

Many health care systems claim to incorporate the cost-effectiveness criterion in their investment decisions. Information on the system's willingness to pay per effectiveness unit, normally measured as quality-adjusted life-years (QALYs), however, is not available in most countries. This is partly because of the controversy that remains around the use of a cost-effectiveness threshold, about what the threshold ought to represent, and about the appropriate methodology to arrive at a threshold value.

OBJECTIVES

The aim of this article was to identify and critically appraise the conceptual perspectives and methodologies used to date to estimate the cost-effectiveness threshold.

METHODS

We provided an in-depth discussion of different conceptual views and undertook a systematic review of empirical analyses. Identified studies were categorized into the two main conceptual perspectives that argue that the threshold should reflect 1) the value that society places on a QALY and 2) the opportunity cost of investment to the system given budget constraints.

RESULTS

These studies showed different underpinning assumptions, strengths, and limitations, which are highlighted and discussed. Furthermore, this review allowed us to compare the cost-effectiveness threshold estimates derived from different types of studies. We found that thresholds based on society's valuation of a QALY are generally larger than thresholds resulting from estimating the opportunity cost to the health care system.

CONCLUSIONS

This implies that some interventions with positive social net benefits, as informed by individuals' preferences, might not be an appropriate use of resources under fixed budget constraints.

How you ask is what you get: Framing effects in willingness-to-pay for a QALY

In decisions on financing new and innovative health care technologies a central question is how to determine the value citizens place on the gains in health and life expectancy that result from respective medical treatments. We report results of surveys of four representative samples of the German population. In 2010 and 2012, in total about 5000 respondents were asked for their willingness-to-pay (WTP) for either an extension of their life or an improvement in their health corresponding to a gain of one quality-adjusted life year (QALY). Specific changes of the study design allow for ceteris paribus comparisons of different survey versions. While the initial version exactly copied a questionnaire used in the EuroVaQ (European Value of a QALY) project, which was conducted in nine European countries and Palestine, but not in Germany, in other versions the wording and the survey technique were modified. The findings show that the technique of posing the questions plays an important role when respondents are asked to imagine being in hypothetical situations. This clearly refers to the wording of the questions and the survey setting (personal or online interview). But even simple design elements such as putting a yes/no filter in front greatly affect the answers in terms of both the frequency of zero WTP and the distribution of positive amounts. From the different results, we conclude that it is inevitable to conduct studies comprising a broad variety of versions when trying to elicit WTP for a specific type of QALY in order to achieve an array of values combined by insights into the principles of their sensitivity.

The Willingness to Pay for a Quality Adjusted Life Year: A Review of the Empirical Literature

There has been a rapid increase in the use of cost-effectiveness analysis, with quality adjusted life years (QALYs) as an outcome measure, in evaluating both medical technologies and public health interventions. Alongside, there is a growing literature on the monetary value of a QALY based on estimates of the willingness to pay (WTP). This paper conducts a review of the literature on the WTP for a QALY. In total, 24 studies containing 383 unique estimates of the WTP for a QALY are identified. Trimmed mean and median estimates amount to 74,159 and 24,226 Euros (2010 price level), respectively. In regression analyses, the results indicate that the WTP for a QALY is significantly higher if the QALY gain comes from life extension rather than quality of life improvements. The results also show that the WTP for a QALY is dependent on the size of the QALY gain valued. Copyright © 2014 John Wiley & Sons, Ltd.

Strengthening tuberculosis control overseas: who benefits?

BACKGROUND

Although tuberculosis is a major cause of morbidity and mortality worldwide, available funding falls far short of that required for effective control. Economic and spillover consequences of investments in the treatment of tuberculosis are unclear, particularly when steep gradients in the disease and response are linked by population movements, such as that between Papua New Guinea (PNG) and the Australian cross-border region.

OBJECTIVE

To undertake an economic evaluation of Australian support for the expansion of basic Directly Observed Treatment, Short Course in the PNG border area of the South Fly from the current level of 14% coverage.

METHODS

Both cost-utility analysis and cost-benefit analysis were applied to models that allow for population movement across regions with different characteristics of tuberculosis burden, transmission, and access to treatment. Cost-benefit data were drawn primarily from estimates published by the World Health Organization, and disease transmission data were drawn from a previously published model.

RESULTS

Investing $16 million to increase basic Directly Observed Treatment, Short Course coverage in the South Fly generates a net present value of roughly $74 million for Australia (discounted 2005 dollars). The cost per disability-adjusted life-year averted and quality-adjusted life-year saved for PNG is $7 and $4.6, respectively.

CONCLUSIONS

Where regions with major disparities in tuberculosis burden and health system resourcing are connected through population movements, investments in tuberculosis control are of mutual benefit, resulting in net health and economic gains on both sides of the border. These findings are likely to inform the case for appropriate investment in tuberculosis control globally.

Willingness to pay for a quality-adjusted life year: an evaluation of attitudes towards risk and preferences

Background

This paper examines the Willingness to Pay (WTP) for a quality-adjusted life year (QALY) expressed by people who attended the healthcare system as well as the association of attitude towards risk and other personal characteristics with their response.

Methods

Health-state preferences, measured by EuroQol (EQ-5D-3L), were combined with WTP for recovering a perfect health state. WTP was assessed using close-ended, iterative bidding, contingent valuation method. Data on demographic and socioeconomic characteristics, as well as usage of health services by the subjects were collected. The attitude towards risk was evaluated by collecting risky behaviors data, by the subject’s self-evaluation, and through lottery games.

Results

Six hundred and sixty two subjects participated and 449 stated a utility inferior to 1. WTP/QALY ratios varied significantly when payments with personal money (mean €10,119; median €673) or through taxes (mean €28,187; median €915) were suggested. Family income, area income, higher education level, greater use of healthcare services, and the number of co-inhabitants were associated with greater WTP/QALY ratios. Age and female gender were associated with lower WTP/QALY ratios. Risk inclination was independently associated with a greater WTP/QALY when “out of pocket” payments were suggested. Clear discrepancies were demonstrated between linearity and neutrality towards risk assumptions and experimental results.

Conclusions

WTP/QALY ratios vary noticeably based on demographic and socioeconomic characteristics of the subject, but also on their attitude towards risk. Knowing the expression of preferences by patients from this outcome measurement can be of interest for health service planning.

The value of a QALY: individual willingness to pay for health gains under risk

BACKGROUND

There is an increased interest in the monetary value of a quality-adjusted life-year (QALY). Past studies commonly derived willingness to pay (WTP) for certain future QALY gains. However, obtaining valid WTP per QALY estimates proved to be difficult.

OBJECTIVE

We conducted a contingent valuation study and estimated the individual WTP per QALY under risk. We demonstrate the impact of probability weighting on WTP per QALY estimates in the Netherlands.

RESULTS

Our estimates of the value of a QALY are in the range of €80,000-110,000 when the weighting correction was applied, and €250,500 without correction. The validity of these estimates, applying probability weighting, appears to be good.

CONCLUSIONS

Given the reasonable support for their validity and practical meaningfulness, the estimates derived while correcting for probability weighting may provide valuable input for the debate on the consumption value of health. While decision makers should not apply these estimates without further consideration, since strictly individual valuations may not carry all relevant information and values for societal decision-making, the current estimates may provide a good and informed basis for further discussion and study of this important topic.

Valuing QALY gains by applying a societal perspective

Interpreting the outcomes of cost utility analyses requires an appropriately defined threshold for costs per quality-adjusted life year (QALY). A common view is that the threshold should represent the (consumption) value a society attaches to a QALY. So far, individual valuations of personal health gains have mainly been studied rather than potentially relevant social values. In this study, we present the first direct empirical estimates of the willingness to pay for a QALY from a societal perspective. We used the contingent valuation approach, valuing QALYs under uncertainty and correcting for probability weighting. The estimates obtained in a representative sample of the Dutch population (n = 1004) range from €52,000 to €83,000, depending on the specification of the societal perspective. The scale sensitivity was weak, however.

Productivity costs in economic evaluations: past, present, future

Productivity costs occur when the productivity of individuals is affected by illness, treatment, disability or premature death. The objective of this paper was to review past and current developments related to the inclusion, identification, measurement and valuation of productivity costs in economic evaluations. The main debates in the theory and practice of economic evaluations of health technologies described in this review have centred on the questions of whether and how to include productivity costs, especially productivity costs related to paid work. The past few decades have seen important progress in this area. There are important sources of productivity costs other than absenteeism (e.g. presenteeism and multiplier effects in co-workers), but their exact influence on costs remains unclear. Different measurement instruments have been developed over the years, but which instrument provides the most accurate estimates has not been established. Several valuation approaches have been proposed. While empirical research suggests that productivity costs are best included in the cost side of the cost-effectiveness ratio, the jury is still out regarding whether the human capital approach or the friction cost approach is the most appropriate valuation method to do so. Despite the progress and the substantial amount of scientific research, a consensus has not been reached on either the inclusion of productivity costs in economic evaluations or the methods used to produce productivity cost estimates. Such a lack of consensus has likely contributed to ignoring productivity costs in actual economic evaluations and is reflected in variations in national health economic guidelines. Further research is needed to lessen the controversy regarding the estimation of health-related productivity costs. More standardization would increase the comparability and credibility of economic evaluations taking a societal perspective.

What explains willingness to pay for smoking-cessation treatments - addiction level, quit-rate effectiveness or the opening bid?

BACKGROUND

Several countries have now passed laws that place limitations on where smokers may smoke. A range of smoking-cessation treatments have become available, many of which have documented increased quit rates. Population surveys show that most smokers wish to quit, and most non-smokers would prefer to reduce the prevalence of smoking in society. The strengths of these preferences, however, as measured by their willingness to pay (WTP), have not yet been investigated.

OBJECTIVE

This study aims to identify variables that explain variations in people's answers to WTP questions on smoking-cessation treatments.

METHODS

A representative sample of the Norwegian population was asked their WTP in terms of an earmarked contribution to a public smoking-cessation programme. A sub-group of daily smokers was, in addition, asked about their WTP for a hypothetical treatment that would remove their urge to smoke. The impact of variation in the question format (different opening bids) on stated WTP was compared with that of factors suggested by economic theory, such as quit-rate effectiveness, degree of addiction as measured by the 12-item Cigarette Dependence Scale (CDS-12), and degree of peer group influence as measured by the proportion of one's friends who smoke.

RESULTS

In both programmes, the most important determinant for explaining variations in WTP was the size of the opening bid. Differences in quit-rate effectiveness did not matter for people's WTP for the smoking-cessation programme. Addiction, and having a small proportion of friends who smoke, were positively associated with smokers' WTP to quit smoking.

CONCLUSION

Variations in WTP were influenced more by how the question was framed in terms of differences in opening bids, than by variables reflecting the quality (effectiveness) and need (addiction level) for the good in question. While the WTP method is theoretically attractive, the findings that outcomes in terms of different quit rates did not affect WTP, and that WTP answers can be manipulated by the chosen opening bid, should raise further doubts on the ability of this method to provide valid and reliable answers that reflect true preferences for health and healthcare.