An experimental investigation of social risk preferences for health.

In this paper, we use the risk apportionment technique of Eeckhoudt, Rey and Schlesinger (2007) to study higher order risk preferences for others' health as well as ex-ante and ex-post inequality preferences for social risky distributions, and their interaction. In an experiment on a sample of university students acting as impartial spectators, we observe risk aversion towards social health losses and a dislike of ex-ante inequality. In addition, evidence for ex-post inequality seeking is much weaker than evidence for ex-ante inequality aversion. Because ex-ante inequality aversion is unrelated to risk aversion, we conclude that simple forms of utilitarianism are not relevant for individual judgment of social risk over health. Last, our investigation of precautionary distribution, which would occur when one particular group in the society suffers from background health risk, shows substantial polarization of preferences. Supplementary Information: The online version contains supplementary material available at 10.1007/s11238-023-09928-w.

Decomposing social risk preferences for health and wealth.

This study reports the results of the first artefactual field experiment designed to measure the prevalence of aversion toward different components of social risks in a large and demographically representative sample. We identify social risk preferences for health and wealth for losses and gains, and decompose these attitudes into four different dimensions: individual risk, collective risk, ex-post inequality, and ex-ante inequality. The results of a non-parametric analysis suggest that aversion to risk and inequality is the mean preference for outcomes in health and wealth in the domain of gains and losses. A parametric decomposition of aversion to risk and inequality shows that respondents are averse to ex-post and ex-ante inequality in health and wealth for gains and losses. Likewise, respondents are averse to collective risk, but neutral to individual risk, which highlights the importance of considering different components of social risk preferences when managing social health and wealth risks.

The formation of physician altruism.

We study how patient-regarding altruism is formed by medical education. We elicit and structurally estimate altruistic preferences using experimental data from a large sample of medical students (N = 733) in Germany at different progress stages in their studies. The estimates reveal substantial heterogeneity in altruistic preferences of medical students. Patient-regarding altruism is highest for freshmen, significantly declines for students in the course of medical studies, and tends to increase again for last year students, who assist in clinical practice. Also, patient-regarding altruism is higher for females and positively associated to general altruism. Altruistic medical students have gained prior practical experience in healthcare, have lower income expectations, and are more likely to choose surgery and pediatrics as their preferred specialty.

Multivariate risk preferences in the quality-adjusted life year model.

The interest in multivariate and higher-order risk preferences has increased. A growing body of literature has demonstrated the relevance and impact of these preferences, but for health the evidence is lacking. We measure multivariate and higher-order risk preferences for quality of life (QoL) and longevity, the two attributes of the Quality-Adjusted Life Year (QALY) model. We observe preferences for a positive correlation between these attributes and for pooling together a fixed loss in one of the attributes and a mean-zero risk in the other, and for pooling together mean-zero risks in QoL and longevity. The findings indicate that higher-order risk preferences are stronger for health than for money. Furthermore, we test if preferences for a risky treatment for a disease affecting only QoL, depend on life expectancy. We find no such a relation, but there is a positive relation between riskiness of a comorbidity affecting life expectancy and risk aversion for a QoL treatment. We therefore observe no definitive deviation from the QALY model, although the model is more robust when expected longevity is high. Our findings suggest that the current practice of cost-effectiveness analysis should be generalized to account for risk aversion in QoL and longevity, and higher-order preferences.

COVID-19-related attitudes, risk perceptions, preventive behaviours and economic impact in sub-Saharan African countries: implementing a longitudinal phone-based survey protocol in rural Senegalese households.

INTRODUCTION: Rural areas are considered safe havens against the increased spread of COVID-19 and associated restrictive measures, especially in contexts where public authorities are not in a position to systematically and substantially ease COVID-19-induced economic shocks. In the current sub-Saharan Africa context, still marked by uncertainty surrounding the spread of COVID-19, we present the protocol of an ongoing longitudinal study aimed at investigating COVID-19-related attitudes, risks perceptions, preventive behaviours and economic impact in rural areas in Senegal. METHODS AND ANALYSIS: A prospective randomised longitudinal study of 600 households located in three semiurban villages and nine randomly selected rural villages in the Niakhar area (located 135 km East of Dakar). Three ad hoc phone surveys are administered to 600 heads of households, their housewives in charge of managing the household and a relative living temporarily in the household, respectively. In addition to sharing identical sets of questions on several topics (risks perceptions, attitudes to curfew, attitudes to vaccines, beliefs about COVID-19 infection), the three separate survey questionnaires also include other topics (economic impact, local preventive strategies) whose related questions differ between questionnaires. As analysing evolutions is the study's primary focus, data on all the topics covered will be collected in three waves unless the spread of COVID-19 by mid-2021 justifies extending data collection. The present article presents the study protocol and details about the implementation of the first wave of data collection which started in July 2020. The decision to wait before presenting the protocol was based on the unprecedented context the COVID-19 pandemic. ETHICS AND DISSEMINATION: The survey's protocol was approved by the Senegalese National Ethical Committee for Research in Health (131/MSAS/CNERS/Sec) and received authorisation from both the Senegalese Ministry of Health (619/MSAS/DPRS/DR) and the French Commission on Information Technology and Liberties (CNIL 2220771).

Beliefs and Risk Perceptions About COVID-19: Evidence From Two Successive French Representative Surveys During Lockdown.

BACKGROUND: The outbreak of COVID-19 has been a major interrupting event, challenging how societies and individuals deal with risk. An essential determinant of the virus' spread is a series of individual decisions, such as wearing face masks in public space. Those decisions depend on trade-offs between costs (or benefits) and risks, and beliefs are key to explain these. METHODS: We elicit beliefs about the COVID-19 pandemic during lockdown in France by means of surveys asking French citizens about their belief of the infection fatality ratio (IFR) for COVID-19, own risk to catch the disease, risk as perceived by others, and expected prevalence rate. Those self-assessments were measured twice during lockdown: about 2 weeks after lockdown started and about 2 weeks before lockdown ended. We also measured the quality of these beliefs with respect to available evidence at the time of the surveys, allowing us to assess the calibration of beliefs based on risk-related socio-demographics. Finally, comparing own risk to expected prevalence rates in the two successive surveys provides a dynamic view of comparative optimism with respect to the disease. RESULTS: The risk perceptions are rather high in absolute terms and they increased between the two surveys. We found no evidence for an impact of personal experience with COVID-19 on beliefs and lower risk perceptions of the IFR when someone in the respondent's family has been diagnosed with a disease. Answers to survey 1 confirmed this pattern with a clear indication that respondents were optimistic about their chances to catch COVID-19. However, in survey 2, respondents revealed comparative pessimism. CONCLUSION: The results show that respondents overestimated the probabilities to catch or die from COVID-19, which is not unusual and does not necessarily reflect a strong deviation from rational behavior. While a rational model explains why the own risk to catch COVID-19 rose between the two surveys, it does not explain why the subjective assessment of the IFR remained stable. The comparative pessimism in survey 2 was likely due to a concomitant increase in the respondents' perceived chances to catch the disease and a decreased expected prevalence rate.

Attitudes about COVID-19 Lockdown among General Population, France, March 2020.

Because the effectiveness of a coronavirus disease lockdown in curbing coronavirus disease spread depends on public support, acquiring real-time information about the way populations reacted to the lockdown is crucial. In France, such public support remained fragile among low-income persons, probably because the lockdown exacerbated preexisting social inequalities and conflicts.

A comparison of individual and collective decision making for standard gamble and time trade-off.

Quality-Adjusted Life-Years (QALYs) are typically derived from individual preferences over health episodes. This paper reports the first experimental investigation into the effects of collective decision making on health valuations, using both time trade-off (TTO) and standard gamble (SG) tasks. We investigated collective decision making in dyads, by means of a mixed-subjects design where we control for learning effects. Our data suggest that collective decision making has little effect on decision quality, as no effects were observed on decision consistency and monotonicity for both methods. Furthermore, QALY weights remained similar between individual and collective decisions, and the typical difference in elicited weights between TTO and SG was not affected. These findings suggest that consulting with others has little effect on health state valuation, although learning may have. Additionally, our findings add to the literature of the effect of collective decision making, suggesting that no such effect occurs for TTO and SG.

Women's Attitudes Toward Invasive and Noninvasive Testing When Facing a High Risk of Fetal Down Syndrome.

Importance: Noninvasive prenatal testing (NIPT) using cell-free DNA in maternal blood is increasingly common compared with invasive testing (IT) in routine antenatal detection of Down syndrome (DS). Objective: To assess attitudes and decision making in pregnant women facing a risk of fetal DS greater than 1 in 250 as established by combined first trimester screening at 11 to 14 weeks of gestation. Design, Setting, and Participants: Survey study in which data were collected from pregnant women at high risk of fetal DS participating in a randomized clinical trial. Data were collected from April 8, 2014, to April 7, 2016, in 57 prenatal diagnosis centers in France. Data were analyzed in 2018. Interventions: Data on attitudes were collected prior to offering randomization between NIPT and IT, whereas data on decision making and test results were collected as part of the clinical trial. Main Outcome and Measures: The primary outcome related to attitudes. A hierarchical cluster analysis was conducted to identify clusters with contrasting attitudes. Logistic regression analyses were used to identify factors associated with attitudes. Results: All 2436 consecutive women to whom the study was proposed (mean [SD] age, 36.3 [5.0] years) answered the questionnaire: 515 (21.1%) expressed preference toward IT with complete karyotyping, whereas 1843 (75.7%) favored NIPT with almost certain but limited information. Hierarchical cluster analysis yielded 4 different clusters that mainly differed in attitudes toward risk taking and extent of information seeking. Factors likely associated with attitudes driven by risk aversion were mostly age and religious beliefs (adjusted odds ratio [aOR], 1.03; 95% CI, 1.00-1.05; P = .03 and aOR, 1.62; 95% CI, 1.29-2.04; P < .001, respectively), whereas higher nuchal translucency measurements by ultrasonography were associated with attitudes driven by ambiguity aversion (aOR, 1.67; 95% CI, 1.27-2.20; P < .001). For attitudes involving both risk and ambiguity aversion at different extents, lower education was associated with highly valuing all possibilities of getting information on pregnancy, whereas higher education was associated with highly valuing information on fetal DS as a primary concern (aOR, 0.54; 95% CI, 0.44-0.67; P < .001 and aOR, 1.44; 95% CI, 1.20-1.74; P < .001, respectively). In all, decision making was in line with attitudes. Conclusions and Relevance: Aversion to risk of fetal loss related to IT and aversion to ambiguity generated by incomplete information from NIPT played a major role in shaping attitudes and decision making. Informed decision making should require pregnant women at high risk of DS to receive extensive information on targeted abnormalities by both tests.

Measuring multivariate risk preferences in the health domain.

We investigate univariate and multivariate risk preferences for health (longevity) and wealth. We measure attitudes toward correlation and attitudes toward higher order dependence structures such as cross-prudence and cross-temperance, making use of the risk apportionment technique proposed by Eeckhoudt et al. (2007). For multivariate gains, we find correlation aversion and cross-prudence in longevity and wealth. For losses, we observe correlation seeking and cross-imprudence. We do not find clear evidence for cross-temperance. Our results indicate that longevity and wealth are considered to be substitutes for gains, but not for losses. Second, univariate (higher order) risk preferences are comparable for longevity and wealth, although somewhat closer to linearity for wealth. Third, we find evidence that attitudes toward dependence structures in the health domain are sign-dependent.

Ambiguity preferences for health.

In most medical decisions, probabilities are ambiguous and not objectively known. Empirical evidence suggests that people's preferences are affected by ambiguity. Health economic analyses generally ignore ambiguity preferences and assume that they are the same as preferences under risk. We show how health preferences can be measured under ambiguity, and we compare them with health preferences under risk. We assume a general ambiguity model that includes many of the ambiguity models that have been proposed in the literature. For health gains, ambiguity preferences and risk preferences were indeed the same. For health losses, they differed with subjects being more pessimistic in decision under ambiguity. Utility and loss aversion were the same for risk and ambiguity. Our results imply that reducing the clinical ambiguity of health losses has more impact than reducing the ambiguity of health gains, that utilities elicited with known probabilities may not carry over to an ambiguous setting, and that ambiguity aversion may impact value of information analyses if losses are involved. These findings are highly relevant for medical decision making, because most medical interventions involve losses.

Discounting health and money: New evidence using a more robust method.

This study compares discounting for money and health in a field study. We applied the direct method, which measures discounting independent of utility, in a representative French sample, interviewed at home by professional interviewers. We found more discounting for money than for health. The median discount rates (6.5% for money and 2.2% for health) were close to market interest rates, suggesting that at the aggregate level the direct method solves the puzzle of unrealistically high discount rates typically observed in applied economics. Constant discounting fitted the data better than the hyperbolic discounting models that we considered. The substantial individual heterogeneity in discounting was correlated with age and occupation.

An elicitation of utility for quality of life under prospect theory.

This paper performs several tests of decision analysis applied to the health domain. First, we conduct a test of the normative expected utility theory. Second, we investigate the possibility to elicit the more general prospect theory. We observe risk aversion for gains and losses and violations of expected utility. These results imply that mechanisms governing decisions in the health domain are similar to those in the monetary domain. However, we also report one important deviation: utility is universally concave for the health outcomes used in this study, in contrast to the commonly found S-shaped utility for monetary outcomes, with concave utility for gains and convex utility for losses.

Estimating sign-dependent societal preferences for quality of life.

This paper is the first to apply prospect theory to societal health-related decision making. In particular, we allow for utility curvature, equity weighting, sign-dependence, and loss aversion in choices concerning quality of life of other people. We find substantial inequity aversion, both for gains and losses, which can be attributed to both diminishing marginal utility and differential weighting of better-off and worse-off. There are also clear framing effects, which violate expected utility. Moreover, we observe loss aversion, indicating that subjects give more weight to one group's loss than another group's gain of the same absolute magnitude. We also elicited some information on the effect of the age of the studied group. The amount of inequity aversion is to some extent influenced by the age of the considered patients. In particular, more inequity aversion is observed for gains of older people than gains of younger people.

Time preferences, socioeconomic status and smokers' behaviour, attitudes and risk awareness.

BACKGROUND: Tobacco control policies have succeeded in reducing tobacco use, but the negative correlation between smoking prevalence and socioeconomic status (SES) has increased. This study focused on the relationships between time preferences, SES, and smoking behaviour, attitudes and risk awareness. METHODS: A cross-sectional telephone survey was conducted in France in 2008 on a representative national sample of people aged 18-75 (N = 2000, including 621 smokers) years. Two scales measuring planning horizon and impulsivity and various indicators of SES were introduced into the logistic regressions performed on smoking status and smokers' attitudes to anti-smoking campaigns, quitting attempts, attempts to quit or smoke less, fear of smoking-related cancer and risk perception. RESULTS: Indicators of lower SES and smoking status were correlated with present time orientation and impulsivity. On modelling smoking status, time orientation and lower SES were found to be significant predictors. Among smokers, lower SES and present time orientation were predictive of smoking-related outcomes: little personal concern with anti-tobacco campaigns, not reporting recent behavioural changes, not expressing personal fear of smoking-related cancer and low risk awareness. When time-related preferences were introduced into the analysis, the effects of several lower SES indicators (especially a low educational level) became non-significant. CONCLUSION: The relationship between SES and smoking behaviour, attitudes and beliefs may be partly mediated by time preferences. Time preference is strongly correlated with smoking status, risk perceptions and attitudes towards anti-smoking campaigns. Tobacco control policies should include messages targeting present time-oriented smokers and/or interventions designed to enhance more future-oriented attitudes among smokers.

Responses to increasing cigarette prices in France: how did persistent smokers react?

OBJECTIVES: (1) To build a typology of persistent smokers' reactions to increasing cigarette prices (persistent smokers were defined as smokers who did not quit because of such increases) and (2) to investigate which factors were correlated with their reactions (we considered three categories: no reaction, trying to quit or smoking less, reducing the cost of smoking). METHODS: We used a French national telephone survey (n=2000; 621 smokers) that included questions about smokers' reactions to increasing cigarette prices, as well as questions about their socio-demographic background, personal time perspective, smoking behavior and reasons for smoking. We used logistic regressions to identify which of these factors were linked to smokers' reactions. RESULTS: In response to the increasing cigarette prices, 24% of persistent smokers did not change their smoking habits at all, 31% only reduced the cost of smoking (they neither reduced their consumption nor tried to quit) and 45% tried to give up smoking or reduced their consumption (they also frequently reduced the cost of smoking). Male and older smokers, the more educated ones and the wealthier ones more frequently reported no reaction at all, as did those who smoked to improve their concentration or keep their weight down. Younger and unemployed smokers more frequently opted for spending less on cigarettes, as did those who smoked to forget about their problems. Finally, present-oriented smokers were less prone to try to quit or to reduce their consumption. CONCLUSION: These findings show the need to increase the price of all tobacco products in cooperation with neighboring states. People's reasons for smoking and their personal time perspectives contribute to their reactions to price increases, and different preventive measures are required for each category of persistent smokers.