Experiments in Health Economics and the pandemic

Einleitung / Introduction

Behaving more risk averse in a pandemic can have multiple reasons. Regarding the health aspects, two motives may be to reduce the risk to one’s own health and the health of others. Because preventive actions and contact reduction decreases both one's own risk and the risk to others, it is difficult to find out the true intentions behind these choices by observing only the action itself. Meaning, the choice as well as the outcome may be the result of a selfish or prosocial consideration or a mixture of both. An experimental approach allows us to gain insight into what drives the willingness to take risks in a pandemic.

Methode / Method

We used a novel approach to elicit risk preferences in a pandemic setting experimentally. By an iterative mechanism, we confront participants with the repeated question of whether they are willing to meet a person given a varying probability of already being infected. Since we aim to disentangle the different motives of the willingness to take risks, we implemented three treatment conditions. In one condition, the decision to meet a person only affects the deciding person; in another, it has an influence on the own and other’s outcome; and in a third condition, it only affects others. To account for the consequences on others, we transfer money to a charity. By comparing the maximum infected probability of meeting a person between the different treatments, we are able to investigate the motivation for taking risks. Iteratively measuring the probability enables us to get a precise value of the maximum risk a participant is willing to take. A broad range of 26 different outcomes, probabilities from 0% to 100% in 4% increments, allows us to differentiate properly between the participants by just having four to five decisions for each participant. Additionally, the iterative mechanism prevents mistakes. The experiment is conducted online in November 2022. We aim for over 2,500 observations from seven European countries, including Germany. The study rollout in different countries enables us to conduct cross-country comparisons.

Ergebnisse / Results

We preregistered three hypotheses regarding our research question. First, we hypothesize that prosociality plays a role while deciding under risk, meaning people are willing to meet at a higher probability of being infected if meeting them has no consequences for others, only for themselves. Second, we expect that own risk preferences will play a role, and thus prosociality is not the single driver of the decisions under risk, as we suppose people are willing to meet at a higher probability of being infected if a meeting has no consequences for themselves, only for others. Third, we guess that the treatment effects are comparable across European countries.

AutorInnen

Benedicta Hermanns, University of Hamburg & Hamburg Center for Health Economics

Johanna Kokot, University of Hamburg & Hamburg Center for Health Economics

Einleitung / Introduction

The already uncertain supply of whole blood from donors has been made even more volatile by the COVID-19 pandemic. Potential reasons for the persistence of this shock are unawareness of the supply drop, and fear of infection while donating. The primary aim of this study is to test efficacy of measures used by donation organizations and media to appeal to donors and non-donors to donate blood and ensure donor safety during the COVID-19 pandemic. The secondary aim is to explore why some donors donated less as a result of the pandemic.

Methode / Method

Using a survey experiment with 1,207 participants, we test the effect of informing subjects about donation urgency (shortage information), and secondly, the effect of reducing the potential fear of a SARS-CoV-2 infection (hygiene information) on their inclination to donate before and after the COVID-19 lockdown ended. We corrobotate our results by evidence from previous blood donations, before and during the pandemic.

Ergebnisse / Results

The results show that shortage information increases willingness to donate for prospective blood donors by 15 percentage points (pp), and increases the willingness of (prospective) donors to donate within the next month by 12pp (9pp), on average. Hygiene information reduces the intention of prior donors to donate again by 8pp, on average. Results from previous donations show a 12pp lower likelihood to donate less in 2020 than in 2019 for those who had been informed about shortages by donation organizations.

Zusammenfassung / Conclusion

The results can help explain why there has been persistently low blood donation since the COVID-19 pandemic. Hygiene measures crowded out blood donors at the extensive margin, whereas shortage information crowds in donors at the extensive margin and increases donation speed for both previous donors and prospective blood donors. The results further suggest that interventions focusing on the marginal benefit of donation are more effective than interventions focusing on marginal costs.

AutorInnen

Michael Haylock, Universität Duisburg Essen

Stefanie Ehmann, Universität Tübingen

Anne Heynold

Einleitung / Introduction

Vaccines have proven effective throughout the COVID-19 pandemic. They lower the risk of getting and spreading the virus and can prevent severe illness and death. Thus, vaccinations restored the possibility for individuals to meet more contacts again since they reduce the consequences of infection for individuals and others. Nonetheless, not everyone opts for vaccinations. Possible reasons for this could be organisational costs, fears of side effects or omission bias. This study aims to investigate the extent to which vaccinations lead to changes in risk-taking behaviour in the context of the COVID-19 pandemic. Furthermore, this study investigates the relationship between risk preferences, vaccination uptake and vaccination costs.

Methode / Method

A preregistered online experiment took place between December 2021 and January 2022 with over 3,700 participants in the European COvid Survey (ECOS). The experiment elicits risk preferences in two rounds using the Virus Risk Elicitation Task (ViRET), a framed version of the Bomb Risk Elicitation Task. Participants choose the amount of 25 persons they want to meet, with one of these 25 being infected with the COVID-19 virus. With each additional person met, the participant benefits monetarily. However, they lost the initial endowment provided when they met the infected person. In the first round, participants did not receive a vaccination opportunity. Before the second round, participants had the option of taking a vaccine. The vaccine had an organisational cost and would reduce participants’ losses in case of meeting the infected person. The level of organisational costs varies within the experiment, and the analysis controls for possible round effects.

Ergebnisse / Results

Overall, observations display an experimental vaccination uptake rate of 80%. The variation in organisational costs does not affect this result. The results also display behavioural changes with increasing numbers of persons met after vaccination. This result might be attributable to a lower potential loss when individuals come in contact with an infected person. Preliminary analysis suggests that this behaviour change is similar across the included European countries and shows heterogeneity between countries regarding the vaccination uptake rate, individual risk preferences and changes in risk preferences.

Zusammenfassung / Conclusion

Risk-averse and risk-seeking participants have incentives to opt for vaccination. The former face an incentive to minimise losses and increase certainty in outcomes, and the latter can reduce the results of highly possible losses due to their risk-seeking behaviour. The experiment provides a deeper understanding of underlying factors and motives behind individual vaccination decisions and accounts for country-specific differences in vaccination uptake.

AutorInnen

Johanna Kokot, Hamburg Centre for Health Economics (HCHE)

Benedicta Hermanns, Hamburg Centre for Health Economics (HCHE)

Philip Huynh, Hamburg Centre for Health Economics (HCHE)