Value of a QALY and VSI estimated with the chained approach

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.

Socioeconomic per-case costs of stroke, myocardial infarction, and preterm birth attributable to air pollution in Sweden

BACKGROUND

Incident cases of stroke, myocardial infarction, and preterm birth have established exposure-response functions associated with air pollution. However, there are no studies reporting detailed costs per case for these health outcomes that are adapted to the cost-benefit tools that guide the regulation of air pollution.

OBJECTIVES

The primary objective was to establish non-fatal per-case monetary estimates for stroke, myocardial infarction, and preterm birth attributable to air pollution in Sweden, and the secondary objective was to ease the economic evaluation process of air pollution morbidity effects and their inclusion in cost-benefit assessments.

METHODS

Based on recommendations from the literature, the case-cost analysis considered direct and indirect medical costs, as well as production losses and informal costs relevant for the calculation of the net present value. A literature search was conducted to estimate the costs of each category for each incident case in Sweden. Informal costs were estimated using the quality-adjusted life-years approach and the corresponding willingness-to-pay in the Swedish population. The total average per-case cost was estimated based on specific health outcome durations and severity and was discounted by 3.5% per year. Sensitivity analysis included varying discount rates, severity of health outcome, and the range of societal willingness to pay for quality-adjusted life years.

RESULTS

The average net present value cost estimate was €2016 460k (185k-1M) for non-fatal stroke, €2016 24k (16k-38k) for myocardial infarction, and €2016 34k (19k-57k) for late preterm birth. The main drivers of the per-case total cost estimates were health outcome severity and societal willingness to pay for risk reduction. Varying the discount rate had the largest effect on preterm birth, with costs changing by ±30% for the discount rates analysed.

RECOMMENDATION

Because stroke, myocardial infarction, and preterm birth have established exposure-response functions linking these to air pollution, cost-benefit analyses should include the costs for these health outcomes in order to adequately guide future air pollution and climate change policies.

Cost-Effectiveness Analysis of PET-CT Surveillance After Treatment of Human Papillomavirus-Positive Oropharyngeal Cancer

OBJECTIVE

To determine the cost-effectiveness of surveillance imaging with PET/CT scan among patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma.

STUDY DESIGN

Cost-effectiveness analysis.

SETTING

Oncologic care centers in the United States with head and neck oncologic surgeons and physicians.

METHODS

We compared the cost-effectiveness of 2 posttreatment surveillance strategies: clinical surveillance with the addition of PET/CT scan versus clinical surveillance alone in human papillomavirus-positive oropharyngeal squamous cell carcinoma patients. We constructed a Markov decision model which was analyzed from a third-party payer's perspective using 1-year Markov cycles and a 30-year time horizon. Values for transition probabilities, costs, health care utilities, and their studied ranges were derived from the literature.

RESULTS

The incremental cost-effectiveness ratio for PET/CT with clinical surveillance versus clinical surveillance alone was $89,850 per quality-adjusted life year gained. Flexible fiberoptic scope exams during clinical surveillance would have to be over 51% sensitive or PET/CT scan cost would have to exceed $1678 for clinical surveillance alone to be more cost-effective. The willingness-to-pay threshold at which imaging surveillance was equally cost-effective to clinical surveillance was approximately $80,000/QALY.

CONCLUSION

Despite lower recurrence rates of human papillomavirus-positive oropharyngeal cancer, a single PET/CT scan within 6 months after primary treatment remains a cost-effective tool for routine surveillance when its cost does not exceed $1678. The cost-effectiveness of this strategy is also dependent on the clinical surveillance sensitivity (flexible fiberoptic pharyngoscopy), and willingness-to-pay thresholds which vary by country.

Cost utility analysis of strategies for minimizing risk of duodenoscope-related infections

BACKGROUND AND AIMS

Transmission of multidrug-resistant organisms by duodenoscopes during ERCP is problematical. The U.S. Food and Drug Administration recently recommended transitioning away from reusable fixed-endcap duodenoscopes to those with innovative device designs that make reprocessing easier, more effective, or unnecessary. Partially disposable (PD) duodenoscopes with disposable endcaps and fully disposable (FD) duodenoscopes are now available. We assessed the relative cost of approaches to minimizing infection transmission, taking into account duodenoscope-transmitted infection cost.

METHODS

We developed a Monte Carlo analysis model in R (R Foundation for Statistical Computing, Vienna, Austria) with a multistate trial framework to assess the cost utility of various approaches: single high-level disinfection (HLD), double HLD, ethylene oxide (EtO) sterilization, culture and hold, PD duodenoscopes, and FD duodenoscopes. We simulated quality-adjusted life years (QALYs) lost by duodenoscope-transmitted infection and factored this into the average cost for each approach.

RESULTS

At infection transmission rates <1%, PD duodenoscopes were most favorable from a cost utility standpoint in our base model. The FD duodenoscope minimizes the potential for infection transmission and is more favorable from a cost utility standpoint than use of reprocessable duodenoscopes after single or double HLD at all infection rates, EtO sterilization for infection rates >.32%, and culture and hold for infection rates >.56%. Accounting for alternate scenarios of variation in hospital volume, QALY value, post-ERCP lifespan, and environmental cost shifted cost utility profiles.

CONCLUSIONS

Our model indicates that PD duodenoscopes represent the most favorable option from a cost utility standpoint for ERCP, with anticipated very low infection transmission rates and a low-cost disposable element. These data underscore the importance of cost calculations that account for the potential for infection transmission and associated patient morbidity/mortality.

Is prevention of suicide worth less? A comparison of the value per statistical life

This paper compares the value per statistical life (VSL) in the context of suicide prevention to that of prevention of traffic fatalities. We conducted a contingent valuation survey with questions on willingness to pay (WTP) in both contexts by administering a web questionnaire to 1038 individuals aged 18 to 80. We conjectured that WTP for a given impact on the number of fatalities would be lower for suicide prevention because suicide, at least to some degree, is the result of individuals' own decisions. However, this hypothesis was not supported by the within- or between-sample estimates of WTP or by responses to direct questions. Hence, no support is provided for the use of a lower valuation of the impact of suicide prevention than for risk-reducing programs in other fields, such as traffic safety. This implies that the same VSL should be used for evaluating suicide prevention interventions and for risk-reducing programs in other policy areas and funds for the prevention of fatalities should be directed to the area with the lowest cost per life saved.

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.

Value of willingness to pay for a QALY gained in Iran; a modified chained-approach

BACKGROUND

Due to the lack of a constant Willingness to Pay per one additional Quality Adjusted Life Years gained based on the preferences of Iran's general public, the cost-effectiveness of health system interventions is unclear and making it challenging to apply economic evaluation to health resources priority setting.

METHODS

We have measured this cost-effectiveness threshold with the participation of 2854 individuals from five provinces, each representing an income quintile, using a modified Time Trade-Off-based Chained-Approach. In this online-based empirical survey, to extract the health utility value, participants were randomly assigned to one of two green (21121) and yellow (22222) health scenarios designed based on the earlier validated EQ-5D-3L questionnaire.

RESULTS

Across the two health state versions, mean values for one QALY gain (rounded) ranged from $6740-$7400 and $6480-$7120, respectively, for aggregate and trimmed models, which are equivalent to 1.35-1.18 times of the GDP per capita. Log-linear Multivariate OLS regression analysis confirmed that respondents were more likely to pay if their income, disutility, and education level were higher than their counterparts.

CONCLUSIONS

In the health system of Iran, any intervention that is with the incremental cost-effectiveness ratio, equal to and less than 7402.12 USD, will be considered cost-effective.

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).

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.

Annual dementia incidence and monetary burden attributable to fine particulate matter (PM2.5) exposure in Sweden

BACKGROUND

Alzheimer's disease (AD) and other dementias currently represent the fifth most common cause of death in the world, according to the World Health Organization, with a projected future increase as the proportion of the elderly in the population is growing. Air pollution has emerged as a plausible risk factor for AD, but studies estimating dementia cases attributable to exposure to fine particulate matter (PM_2.5) air pollution and resulting monetary estimates are lacking.

METHODS

We used data on average population-weighted exposure to ambient PM_2.5 for the entire population of Sweden above 30 years of age. To estimate the annual number of dementia cases attributable to air pollution in the Swedish population above 60 years of age, we used the latest concentration response functions (CRF) between PM_2.5 exposure and dementia incidence, based on ten longitudinal cohort studies, for the population above 60 years of age. To estimate the monetary burden of attributable cases, we calculated total costs related to dementia, including direct and indirect lifetime costs and intangible costs by including quality-adjusted life years (QALYs) lost. Two different monetary valuations of QALYs in Sweden were used to estimate the monetary value of reduced quality-of-life from two different payer perspectives.

RESULTS

The annual number of dementia cases attributable to PM_2.5 exposure was estimated to be 820, which represents 5% of the annual dementia cases in Sweden. Direct and indirect lifetime average cost per dementia case was estimated to correspond € 213,000. A reduction of PM_2.5 by 1 μg/m³ was estimated to yield 101 fewer cases of dementia incidences annually, resulting in an estimated monetary benefit ranging up to 0.01% of the Swedish GDP in 2019.

CONCLUSION

This study estimated that 5% of annual dementia cases could be attributed to PM_2.5 exposure, and that the resulting monetary burden is substantial. These findings suggest the need to consider airborne toxic pollutants associated with dementia incidence in public health policy decisions.

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.