Private and social time preferences for health and money: an empirical estimation

Alternative Paradigms in Animal Health Decisions: A Framework for Treating Animals Not Only as Commodities

Simple Summary

Since zoonotic diseases can be transmitted from animals to humans, more comprehensive measures are needed when preventing and controlling these diseases. Because the value of animals is mainly based on monetary terms, animals are typically treated as commodities, impacting public health decisions. Therefore, a framework is proposed to value the health of animals beyond money for public health decision-making with a “One Health” approach. The aim is to have more comprehensive animal values based on the opinion of societies. However, tackling the dilemmas related to animal diseases, public health, and welfare still represents a challenge and a work in progress.

Abstract

Zoonoses are diseases transmitted from (vertebrate) animals to humans in the environment. The control and prevention of these diseases require an appropriate way to measure health value for prudent and well-balanced decisions in public health, production costs, and market values. Currently, the impact of diseases and animal disease control measures are typically assessed in monetary values, thus lacking consideration of other values such as emotional, societal, ecological, among others. Therefore, a framework is proposed that aims to explore, understand, and open up a conversation about the non-monetary value of animals through environmental and normative ethics. This method might help us complement the existing metrics in health, which are currently DALY and zDALY, adding more comprehensive values for animal and human health to the “One Health” approach. As an example of this framework application, participants can choose what they are willing to give in exchange for curing an animal in hypothetical scenarios selecting a human health condition to suffer, the amount of money, and lifetime as a tradeoff. Considering animals beyond their monetary value in public health decisions might contribute to a more rigorous assessment of the burden of zoonotic diseases, among other health decisions. This study is structured as follows: after a brief introduction of zoonoses, animal health, and health metrics, briefly, different environmental health perspectives are presented. Based on this, a framework for animal health decisions is proposed. This framework introduces the “anthropozoocentric interface” based on anthropocentrism and zoocentrism perspectives.

Delay Effect and Subadditivity. Proposal of a New Discount Function: The Asymmetric Exponential Discounting

The framework of this paper is intertemporal choice and, more specifically, the so-called delay effect. Traditionally, this anomaly, also known as decreasing impatience, has been revealed when individuals reverse their preferences over monetary or non-monetary rewards. In this manuscript, we will analyze the delay effect by using preference relations and discount functions. The treatment of the delay effect with discount functions exhibits several scenarios for this paradox. Thus, the objective of this paper is to deduce the different expressions of the delay effect and their mathematical characterizations by using discount functions in stationary and dynamic settings. In this context, subadditivity will be derived as a particular case of decreasing impatience. Finally, we will introduce a new discount function, the so-called asymmetric exponential discount function, able to describe decreasing impatience.

Patient and physician preferences for type 2 diabetes medications: a systematic review

Background

There are several treatments to cure type 2 diabetes (T2D) and every one of them has certain attributes which is lead patients and specialists to have different preferences and select power. Therefore, we did this systematic study to evaluate patients̓ and physicians̓ preferences for type 2 diabetes medications by extracting attributes of anti-diabetic medications and identifying their relative importance.

Methods

We searched the PubMed, Ovid, Web of science, Scopus and Embase databases for articles which have been published on or before May 8th, 2018(The start time of the search in our study was May 8th, 2018).

Results

The searches identified 3346 studies, of which 17 (from 2009 to 2017) were included in the final synthesis and 27 attributes of type 2 anti-diabetic have been investigated. The most important attributes are changes of blood glucose and HbA1c level, hypoglycemia events, weight changes, gastrointestinal complications, cardiovascular effects, medicines cost, and administration mode and dosage of medicines.

Conclusion

physicians and patients prefer antidiabetics which is reduce blood glucose and HbA1c level effectively and have low side effects too (hypoglycemic event, cardiovascular and gastrointestinal). The effect of weight reduction, low cost, low dosing and low frequency of using. Health care providers, Specialist, and manufacturers should consider to these attributes in treatment process and marketing. It can increase adherence to management approaches, and reduce morbidity of patients with type 2 diabetes.

Private and social time preference for health outcomes: A general population survey in Iran

Despite the recent increase in economic evaluations of health care programs in low and middle income countries, there is still a surprising gap in evidence on the appropriate discount rate and the discounting of health outcomes such as quality adjusted life years (QALYs). Our study aimed to calculate the implied time preference rate for health outcomes in Iran and its key determinants. Data were gathered from one family member from each of the 650 households randomly selected in Tehran. The respondents’ private and social preferences for health outcomes were calculated using the time trade-off (TTO) technique based on the discounted utility model. We investigated the main assumptions of the discounted utility model through equality of mean comparison, and the association between private time preference and key socio-economic determinants using multilevel regression analysis. The mean and median implied rates were 5.8% and 4.9% for private time preference and 25.6% and 20% for social time preference respectively. Our study confirmed that magnitude, framing and time effects have a significant impact on implied discount rates, which means that the conventional discounted utility model’s main assumptions are violated in the Iranian general population. Other models of discounting which apply lower rates for far health outcomes might provide a more sensible solution to discounting health interventions with long-term impacts.

A comparison of professional and private time preferences of General Practitioners

In a perfect agency relationship, doctors consider all information and select the patient's 'utility maximising' option given the patient's preferences. The patient's time preferences are important as treatments vary in the timing and length of their benefits. However, doctors often do not have full information on patients' preferences and may apply their own preferences. This has generated empirical interest in estimating doctors' time preferences. However, these studies generally elicit doctors' private preferences (preferences for their own health) rather than professional preferences (preferences for the patient). We hypothesise that private and professional preferences may differ. Professional time preferences may be 'taught' in medical school or learned through repeated interactions with patients. If preferences differ then estimates of doctors' private preferences are less informative for medical decision-making. This study compares private and professional time preferences for health in a national sample of General Practitioners, using a between sample design. Time discounting is explored using exponential and quasi-hyperbolic models. We elicit time preferences using multiple price lists. We find no significant difference between the time preference for the self or the patient. This result holds for axiomatic discounting classification and maximum likelihood estimates. We do not find evidence of present-bias. There are a high proportion of increasingly impatient GPs, potentially implying a maximum 'willingness to wait' for treatment benefits. GPs value the health state differently between themselves or for a patient. These results suggest that we can use estimates of private preferences from doctors to inform medical decision-making.

Factors affecting participation in health checkups: Evidence from Japanese survey data

Multiple factors influence individuals to get health checkups. This study investigates key determinants of the health checkup decision by using 2696 Japanese respondents' data from a questionnaire survey entitled "Preference Parameters Study" that was conducted in four countries by the Global Centers of Excellence program at Osaka University. In the Probit and OLS regressions, other than relevant personal attributes being identified, the hyperbolic discounter dummy and its interaction terms with respondents' health behaviors were also included as independent variables. The results suggest that some socio-demographic variables such as gender, age, income, household size, occupational status, educational level are significant. In addition, hyperbolic discounters are found to be more likely than non-hyperbolic discounters to seek health checkups, which indicates that the effect of time preference on health checkup behavior differs significantly among the different types of time discount structures.

Discounting in Economic Evaluations

Appropriate discounting rules in economic evaluations have received considerable attention in the literature and in national guidelines for economic evaluations. Rightfully so, as discounting can be quite influential on the outcomes of economic evaluations. The most prominent controversies regarding discounting involve the basis for and height of the discount rate, whether costs and effects should be discounted at the same rate, and whether discount rates should decline or stay constant over time. Moreover, the choice for discount rules depends on the decision context one adopts as the most relevant. In this article, we review these issues and debates, and describe and discuss the current discounting recommendations of the countries publishing their national guidelines. We finish the article by proposing a research agenda.

The role of time and risk preferences in adherence to physician advice on health behavior change

Changing physical activity and dietary behavior in chronic disease patients is associated with significant health benefits but is difficult to achieve. An often-used strategy is for the physician or other health professional to encourage behavior changes by providing advice on the health consequences of such behaviors. However, adherence to advice on health behavior change varies across individuals. This paper uses data from a population-based cross-sectional survey of 1849 individuals with chronic disease to explore whether differences in individuals' time and risk preferences can help explain differences in adherence. Health behaviors are viewed as investments in health capital within the Grossman model. Physician advice plays a role in the model in that it improves the understanding of the future health consequences of investments. It can be hypothesized that the effect of advice on health behavior will depend on an individuals' time and risk preference. Within the survey, which measured a variety of health-related behaviors and outcomes, including receipt and compliance with advice on dietary and physical activity changes, time preferences were measured using financial planning horizon, and risk preferences were measured through a commonly used question which asked respondents to indicate their willingness to take risks on a ten-point scale. Results suggest that time preferences play a role in adherence to physical activity advice. While time preferences also play a role in adherence to dietary advice, this effect is only apparent for males. Risk preferences do not seem to be associated with adherence. The results suggest that increasing the salience of more immediate benefits of health behavior change may improve adherence.

Comparing time and risk preferences across three post-industrial UK cities

Time and risk preferences are known to vary considerably across individuals but less is known about the determinants of these individual differences. This paper examines whether preferences vary by geographical location. The motivation for examining geographic heterogeneity is the higher level of mortality experienced in Glasgow over and above that explained by deprivation, sometimes referred to as the 'Glasgow effect'. Data were collected from 3702 individuals across Glasgow, Manchester and Liverpool between July and November 2011. The results show evidence of geographic preference heterogeneity. Contrary to our hypothesis, individuals in Glasgow have a lower rather than higher time preference rate. Individuals in Glasgow are on average more risk seeking compared to Liverpool and more likely to be at the tail end of the distribution (very risk seeking) compared to Manchester. Differences in risk preferences may help explain some of the differences in mortality associated with risky health behaviours such as drug and alcohol use. However, individuals in Glasgow were also more future oriented suggesting that they are less likely to engage in risky healthy behaviours. As the differences in time and risk preferences work in opposite directions in terms of health investments it less likely that these differences can help explain excess mortality in Glasgow.

Differential time preferences for money and quality of life

BACKGROUND

This study provides an empirical investigation into differential time preferences between money and quality of life. Thus far, time preference investigations in health have mostly involved life-years gained and lives saved. However, the quality-adjusted life-year, which is recommended by several bodies, is a multiplicative measure of life duration and quality of life. To our knowledge, our study is the first to follow this approach specifically for quality of life.

METHODS

A questionnaire was developed to elicit time preferences for quality of life and for money, and it was distributed to a representative sample of the Dutch population. We also investigated the impact of population characteristics, such as current health state, optimistic/pessimistic future views or gender, on time preferences.

RESULTS

We found that discount rates for both money and quality of life decrease with increasing time of delay, with rates of the former being consistently at least two times higher than those of the latter. Similar trends in time preferences were observed across the subgroups, with the exception of the relatively high education subgroup.

CONCLUSION

In agreement with the results of other studies, our empirically derived discount rates are higher than the rates featured in national guidelines for health care economic assessment. Our empirical study adds to the evidence for differential discounting, both with regards to money and health, as well as in time.

Does temporal discounting explain unhealthy behavior? A systematic review and reinforcement learning perspective

The tendency to make unhealthy choices is hypothesized to be related to an individual's temporal discount rate, the theoretical rate at which they devalue delayed rewards. Furthermore, a particular form of temporal discounting, hyperbolic discounting, has been proposed to explain why unhealthy behavior can occur despite healthy intentions. We examine these two hypotheses in turn. We first systematically review studies which investigate whether discount rates can predict unhealthy behavior. These studies reveal that high discount rates for money (and in some instances food or drug rewards) are associated with several unhealthy behaviors and markers of health status, establishing discounting as a promising predictive measure. We secondly examine whether intention-incongruent unhealthy actions are consistent with hyperbolic discounting. We conclude that intention-incongruent actions are often triggered by environmental cues or changes in motivational state, whose effects are not parameterized by hyperbolic discounting. We propose a framework for understanding these state-based effects in terms of the interplay of two distinct reinforcement learning mechanisms: a “model-based” (or goal-directed) system and a “model-free” (or habitual) system. Under this framework, while discounting of delayed health may contribute to the initiation of unhealthy behavior, with repetition, many unhealthy behaviors become habitual; if health goals then change, habitual behavior can still arise in response to environmental cues. We propose that the burgeoning development of computational models of these processes will permit further identification of health decision-making phenotypes.

Intertemporal discounting as a risk factor for high BMI: evidence from Australia, 2008

This paper explores the relationship between intertemporal discounting and body weight, using stated preference measures of intertemporal discounting, and the body mass index (BMI) to represent relative body weight. The empirical analysis uses Australian data obtained in 2008 through the South Australian Health Omnibus Survey. A quantile regression analysis is used to allow the marginal effects of the explanatory variables on BMI to vary across the conditional BMI distribution. It is shown that an indicator of intertemporal discounting elicited from a hypothetical monetary trade-off has a significant positive relationship with BMI. This relationship appears to be stronger in the upper quantiles, but there is insufficient statistical evidence for this difference. Evidence is presented that intertemporal discounting is a risk factor for increased BMI with a magnitude of effect comparable to more commonly recognized risk factors such as income and education. However there is no significant relationship found between BMI and an alternative indicator of intertemporal discounting elicited from trade-offs in health status.

Patient preferences for diabetes management among people with type 2 diabetes in Denmark - a discrete choice experiment

OBJECTIVES

To study patient preferences for diabetes-treatment related attributes among people with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Participants were recruited from three diabetes out-patient clinics and two general practitioner surgeries. Data were collected electronically and results were analysed using a standard statistical model designed for choice sets (conditional logit). Six characteristics relating to treatment of diabetes were examined: glycated haemoglobin level (HbA(1c)), weight (gain or loss), hypoglycaemic events, need for injections, transient nausea and need for blood glucose testing.

RESULTS

Two hundred and seventy participants with type 2 diabetes (178 males; 92 females) were included. Patients placed the most value on losing weight and were willing to pay the most to lose 6 kg of weight. Loss of 3 kg of weight was the next highly valued, followed by dropping one percentage point in HbA(1c) level. Avoidance of nausea and a reduction in hypoglycaemic events from two per month to none was also highly valued. Patients were willing to accept one injection per day if they, for instance, simultaneously lost 1.4 kg. A limitation of the study is that the survey was web-based and response rates for such surveys can be extremely variable.

CONCLUSION

Patients with type 2 diabetes in Denmark were willing to pay for the health benefits associated with improved diabetes treatment, the most important of these being weight loss or avoidance of weight gain, and reduction of HbA(1c) and of hypoglycaemic events.

Social time preferences for health and money elicited with a choice experiment

OBJECTIVES

In economic evaluations future health and monetary outcomes are commonly discounted at equal and constant rates. The theoretical foundation of this practice is being debated and appropriate discount rates for costs and health effects are sought. Here, we have derived social discount rates for health, money, and environmental benefits by means of a choice experiment.

METHODS

All choices were framed from a social perspective. We investigated differences in time preference by domain (health, monetary benefits, environmental benefits), time delay (5, 10, and 40 years), and respondent characteristics. Respondents were 173 health-care professionals and 34 health policymakers. Choice titration was used to determine when the respondent was indifferent between future and present benefits.

RESULTS

At least two-thirds of respondents preferred an intervention with immediate benefits to delayed benefits in the different domains. The median (mean) yearly discount rates for health benefits were 2.7% (10.7%), 1.3% (3.5%), and 1.1% (2.3%) assuming a 5, 10, and 40 years delay, respectively. Social time preference for monetary benefits was significantly stronger, with median (mean) yearly discount rates of 6.6% (18.7%) and 4.8% (11.2%) assuming a 5 and 10 years delay, respectively. The social time preference with regard to environmental benefits was similar to the monetary benefits. Social time preference for the different domains was significantly correlated at the individual level.

CONCLUSIONS

The empirically derived social time preference is in line with current theoretical arguments for a lower discount rate for health benefits than for monetary benefits. Moreover, the implied median discount rates for health were lower than those commonly used or advocated in guidelines.

Willingness to pay for health improvements associated with anti-diabetes treatments for people with type 2 diabetes

OBJECTIVES

This study aimed to investigate the most important consequences of diabetes medication, as measured by the patients' willingness to pay (WTP).

RESEARCH DESIGN AND METHODS

People in Sweden were recruited using existing nationwide e-mail panels if they were adults (>or=18 years) with type 2 diabetes and were receiving pharmacological anti-diabetes treatment(s). Data were collected electronically and results were analysed using a standard statistical model designed for choice games (conditional logit). Six characteristics relating to treatment of diabetes were examined: weight (gain or loss), mean glycated haemoglobin level (HbA(1c)), hypoglycaemic events, nausea, need for injections (with or independently of meals), and blood glucose testing.

RESULTS

A total of 461 people with type 2 diabetes (291 males; 170 females) completed an internet questionnaire and were eligible for inclusion. Participants placed high value on weight loss and nausea avoidance; they would pay 176 Swedish Krona (SEK)/euro15.61 per month to lose 1 kg, and would pay SEK 560 (euro49.67) per month to avoid nausea completely. Patients wanting to reduce the number of hypoglycaemic events from three per month to none were willing to pay SEK 419 (euro37.17) per month. Patients valued a 1 percentage point reduction in HbA(1c) at SEK 414 (euro36.72) per month. Participants preferred taking tablets to injections and required a compensation of SEK 376 (euro33.35) to accept one injection/day. Injections independent of meals were preferred to injections with meals (WTP: SEK 140/euro12.42 per month). Potential limitations of this study are that the preferences expressed may not match preferences in real-life situations, and bias through the use of electronic questionnaire, which restricted participation to those with access to, and experience with, the internet.

CONCLUSION

People with type 2 diabetes were willing to pay a considerable amount of money each month to lose weight, reduce or avoid hypoglycaemic events and reduce HbA(1C).

A Generalizability Study of Time Discounting: Some People React More Strongly to Domain Differences Than Others

Whereas individual differences in the degree of time discounting have been found to be meaningfully related to important outcome variables, some researchers have reported evidence that individual differences in time discounting cannot be generalized among domains - a phenomenon called domain independence. However, the Participant × Domain interaction and its importance in relation to the main effect of domain have never been studied. In the present paper, generalizability analysis is used for the first time to separate the sources of variance in time discounting choices (into differences between participants, domains, magnitudes, delays, and their interactions). Results show that the most important source of variance is the Participant × Domain interaction. Differences between participants and between magnitudes were also important. Thus, several sources of variance in time discounting choices should be acknowledged. Most importantly, people seem to differ in their reaction to domains.

Methods for measuring temporary health States for cost-utility analyses

A variety of methods are available to measure preferences for temporary health states for cost-utility analyses. The objectives of this review were to summarize the available temporary health-state valuation methods, identify advantages and disadvantages of each, and identify areas for future research. We describe the key aspects of each method and summarize advantages and disadvantages of each method in terms of consistency with QALY theory, relevance to temporary health-state-specific domains, ease of use, time preference, and performance in validation studies. Two broad categories of methods were identified: traditional and adapted. Traditional methods were health status instruments, time trade-off (TTO), and the standard gamble (SG). Methods adapted specifically for temporary health-state valuation were TTO with specified duration of the health state, TTO with a lifespan modification, waiting trade-off, chained approaches for TTO and SG, and sleep trade-off. Advantages and disadvantages vary by method and no 'gold standard' method emerged. Selection of a method to value temporary health states will depend on the relative importance of the following considerations: ability to accurately capture the unique characteristics of the temporary health state, level of respondent burden and cognition, theoretical consistency of elicited preference values with the overall purpose of the study, and resources available for study development and data collection. Further research should focus on evaluating validity, reliability and feasibility of temporary health-state valuation methods.

Estimation of private and social time preferences for health in northern Tanzania

Time preferences for health has a role in informing discounting practice in economic evaluation of health care interventions. Yet virtually no empirical evidence on time preferences for health are available for sub-Saharan Africa. The objectives of this paper are therefore to estimate time preferences for health in Tanzania, and to explore the relationship between time preferences for one's own private health and for others health. Determinants of time preference rates are also explored. A sample of the general population participated, and each person was asked to indicate the maximum duration of more distant ill-health they would be willing to accept in return for a specified delay in the onset of the condition. People were randomised to answer either questions in the context of their own health or in the context of others health. Estimations were done using clustered least squares regression with robust standard errors. The implied mean and median discount rates were 0.07 and 0.058, respectively. Time preferences for one's own and others' health--conceptualised as social health--seem to be roughly the same in this sample, but people seem to discount the most severe health condition at a significantly lower rate than the least severe condition.

Societal discounting of health effects in cost-effectiveness analyses: the influence of life expectancy

BACKGROUND

Increasing life expectancy and decreasing marginal valuation of additional QALYs over time may serve as a basis for discounting future health effects from a societal perspective. Therefore, we tested the hypothesis that societal time preference for health is related to perceived future life expectancy.

METHODS

A sample of 223 people from the general population prioritised healthcare programmes with differential timing of health benefits and costs from a societal perspective. Furthermore, we asked respondents to estimate future life expectancy.

RESULTS

The relationship between future life expectancy and time preference for health is ambiguous. We observed that people who expected a higher future life expectancy elicited higher discount rates for health effects than those with lower life expectancy growth expectations for all four time periods (5, 10, 20 and 40 years into the future), but the differences were never significant. On average, providing explicit information on growth in life expectancy did significantly alter discount rates in the expected direction but, on an individual level, the results were rather inconsistent. We observed a significantly stronger time preference (i.e. higher discount rates) for health effects than for costs. As commonly observed, discount rates for health and money decreased with time delay following a hyperbolic function.

CONCLUSION

Our data indicate that it is troublesome to elicit societal discount rates empirically, especially rates that are in line with the theoretical arguments on societal discounting. The influence of life expectancy remains ambiguous, but there seems to be at least some positive relationship between growth in life expectancy and discount rates that deserves additional attention.

Valuing prevention through economic evaluation: some considerations regarding the choice of discount model for health effects with focus on infectious diseases

In cost-effectiveness analysis, the valuing of costs and health effects over time remains a controversial issue. The debate mostly focuses on whether the discount rates for health and money should be equal and which discounting model and time preferences are most appropriate. In this paper we add to the debate by arguing that the assessment of effectiveness of a preventive intervention may influence the choice of the discounting procedure for health. Health effects in cost-effectiveness analysis are commonly expressed in life-years gained, QALYs gained or lives saved. These denominators are only indirect and partial measures of the effects of a preventive intervention. The actual effect of the intervention is a reduction of the risk of mortality and morbidity in a given period of time. This risk reduction will not always coincide with the moment at which the impact on (quality-adjusted) life-years gained is made (i.e. at risk exposure), for example when preventing chronic disease with an asymptomatic stage. In this paper we show that truly acknowledging the origin of health benefits could have implications for the discounting procedure. We present a discounting model that adequately focuses on the reduction of risk. This model recognises the potential interpretation of risk reduction for infection as an economic good to be acquired with associated mortality reductions as later indirect effects. This implies that our suggested discounting model focuses on the moment(s) of risk reduction. A numerical example illustrates our approach. We discuss the associated potential implications for public health policy and discuss how the effects of the intervention can be additionally corrected for societal preferences.

Theoretical arguments for the discounting of health consequences: where do we go from here?

Despite the theoretical arguments presented in the literature regarding discounting over the last 25 years, no satisfactory reply has yet been offered to the question of whether health consequences have to be discounted at the same rate as monetary consequences in the economic evaluation of health programmes or interventions designed to improve health. Against this background, the main objective of this paper was to review and systemise these theoretical arguments, with the aim of determining whether any of the positions identified can be accepted without reservation. Having determined that this is not possible, we investigated the rationality of discounting in the literature and, on this basis, propose a potential way to resolve the problem. Thus, we argue that the relationship between the discount of monetary and health consequences has to be determined in an indirect manner, by reference to the relationship maintained by the individual time preference rates for health and money in the context of private and social choice. Although this proposal moves the debate into the empirical field, its advantages must be weighed against the difficulties associated with the estimation of the time preferences.