Empirical evidence to understand the human factor for effective rapid testing against SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen point-of-care and home tests are available to laypeople. In four cross-sectional mixed-methods data collections conducted between December 2020 and March 2021 (n = 4,026), we showed that a majority of subjects were willing to test despite mistrust and ignorance regarding rapid tests' validity. Experimental evidence shows that low costs and access to events could increase testing intentions. Mandatory reporting and isolation after positive results were not identified as major barriers. Instead, assuming that testing and isolation can slow down the pandemic and the possibility to protect others were related to greater willingness to get tested. While we did not find evidence for risk compensation for past tests, experimental evidence suggests that there is a tendency to show less mask wearing and physical distancing in a group of tested individuals. A short communication intervention reduced complacent behavior. The derived recommendations could make rapid testing a successful pillar of pandemic management.

Vaccination as a social contract.

Most vaccines protect both the vaccinated individual and the society by reducing the transmission of infectious diseases. In order to eliminate infectious diseases, individuals need to consider social welfare beyond mere self-interest-regardless of ethnic, religious, or national group borders. It has therefore been proposed that vaccination poses a social contract in which individuals are morally obliged to get vaccinated. However, little is known about whether individuals indeed act upon this social contract. If so, vaccinated individuals should reciprocate by being more generous to a vaccinated other. On the contrary, if the other doesn't vaccinate and violates the social contract, generosity should decline. Three preregistered experiments investigated how a person's own vaccination behavior, others' vaccination behavior, and others' group membership influenced a person's generosity toward respective others. The experiments consistently showed that especially compliant (i.e., vaccinated) individuals showed less generosity toward nonvaccinated individuals. This effect was independent of the others' group membership, suggesting an unconditional moral principle. An internal metaanalysis (n = 1,032) confirmed the overall social contract effect. In a fourth experiment (n = 1,212), this pattern was especially pronounced among vaccinated individuals who perceived vaccination as a moral obligation. It is concluded that vaccination is a social contract in which cooperation is the morally right choice. Individuals act upon the social contract, and more so the stronger they perceive it as a moral obligation. Emphasizing the social contract could be a promising intervention to increase vaccine uptake, prevent free riding, and, eventually, support the elimination of infectious diseases.

Social and behavioral consequences of mask policies during the COVID-19 pandemic.

Mandatory and voluntary mask policies may have yet unknown social and behavioral consequences related to the effectiveness of the measure, stigmatization, and perceived fairness. Serial cross-sectional data (April 14 to May 26, 2020) from nearly 7,000 German participants demonstrate that implementing a mandatory policy increased actual compliance despite moderate acceptance; mask wearing correlated positively with other protective behaviors. A preregistered experiment (n = 925) further indicates that a voluntary policy would likely lead to insufficient compliance, would be perceived as less fair, and could intensify stigmatization. A mandatory policy appears to be an effective, fair, and socially responsible solution to curb transmissions of airborne viruses.

Allocation of COVID-19 vaccination: when public prioritisation preferences differ from official regulations.

As vaccines against COVID-19 are scarce, many countries have developed vaccination prioritisation strategies focusing on ethical and epidemiological considerations. However, public acceptance of such strategies should be monitored to ensure successful implementation. In an experiment with N=1379 German participants, we investigated whether the public's vaccination allocation preferences matched the prioritisation strategy approved by the German government. Results revealed different allocations. While the government had top-prioritised vulnerable people (being of high age or accommodated in nursing homes for the elderly), participants preferred exclusive allocation of the first available vaccines to medical staff and personnel caring for the elderly. Interestingly, allocation preferences did not change when participants were told how many individuals were included in each group. As differences between allocation policies and public preferences can affect trust in the government and threaten the social contract between generations, we discuss possible strategies to align vaccination prioritisations.

Money is not everything: experimental evidence that payments do not increase willingness to be vaccinated against COVID-19.

Rapid, large-scale uptake of new vaccines against COVID-19 will be crucial to decrease infections and end the pandemic. In a recent article in this journal, Julian Savulescu argued in favour of monetary incentives to convince more people to be vaccinated once the vaccine becomes available. To evaluate the potential of his suggestion, we conducted an experiment investigating the impact of payments and the communication of individual and prosocial benefits of high vaccination rates on vaccination intentions. Our results revealed that none of these interventions or their combinations increased willingness to be vaccinated shortly after a vaccine becomes available. Consequently, decision makers should be cautious about introducing monetary incentives and instead focus on interventions that increase confidence in vaccine safety first, as this has shown to be an especially important factor regarding the demand for the new COVID-19 vaccines.

The four weeks before lockdown during the COVID-19 pandemic in Germany: a weekly serial cross-sectional survey on risk perceptions, knowledge, public trust and behaviour, 3 to 25 March 2020.

BackgroundDuring the COVID-19 pandemic, public perceptions and behaviours have had to adapt rapidly to new risk scenarios and radical behavioural restrictions.AimTo identify major drivers of acceptance of protective behaviours during the 4-week transition from virtually no COVID-19 cases to the nationwide lockdown in Germany (3-25 March 2020).MethodsA serial cross-sectional online survey was administered weekly to ca 1,000 unique individuals for four data collection rounds in March 2020 using non-probability quota samples, representative of the German adult population between 18 and 74 years in terms of age × sex and federal state (n = 3,910). Acceptance of restrictions was regressed on sociodemographic variables, time and psychological variables, e.g. trust, risk perceptions, self-efficacy. Extraction of homogenous clusters was based on knowledge and behaviour.ResultsAcceptance of restrictive policies increased with participants' age and employment in the healthcare sector; cognitive and particularly affective risk perceptions were further significant predictors. Acceptance increased over time, as trust in institutions became more relevant and trust in media became less relevant. The cluster analysis further indicated that having a higher education increased the gap between knowledge and behaviour. Trust in institutions was related to conversion of knowledge into action.ConclusionIdentifying relevant principles that increase acceptance will remain crucial to the development of strategies that help adjust behaviour to control the pandemic, possibly for years to come. Based on our findings, we provide operational recommendations for health authorities regarding data collection, health communication and outreach.

[Public trust in institutions in the first half of the Corona pandemic: findings from the COVID-19 Snapshot Monitoring (COSMO) project]. / Vertrauen der Bevölkerung in staatliche Institutionen im ersten Halbjahr der Coronapandemie: Erkenntnisse aus dem Projekt COVID-19 Snapshot Monitoring (COSMO).

BACKGROUND: In the coronavirus pandemic, two institutions play a central role in the evidence-based classification of events for politics and the population. The Robert Koch Institute (RKI) coordinates the fight against the pandemic, prepares well-founded recommendations for medical professionals, the media and the population, and advises politicians. The Federal Centre for Health Education (BZgA) informs the population and institutions. GOALS: The COVID-19 Snapshot Monitoring (COSMO) project monitors whether and how trust in institutions changes over the pandemic. Which population groups show trust and how this is related to attitudes, risk perception and behaviour are analysed. METHODS: Cross-sectional studies with approximately N = 1000 respondents per survey were conducted since March 2020 to investigate risk perception, behaviour, acceptance of measures and trust in institutions. RESULTS: Trust in the RKI and BZgA was generally high but declined over the course of the pandemic. Higher trust for both institutions was associated with higher age of respondents, higher education, higher risk perception and higher acceptance of measures. Behaviours such as physical distancing and handwashing were shown more frequently. Men and the chronically ill showed lower trust. DISCUSSION: The results show that trust should be further promoted. This could be achieved, among other things, by taking into account the population's perspective (e.g. through COSMO) in the development and justification of strategies and measures. Communication strategies and recommendations for action should aim to support and relieve people with high-risk perceptions.

Individual preferences for voluntary vs. mandatory vaccination policies: an experimental analysis.

BACKGROUND: More and more countries are discussing the introduction of mandatory vaccination policies. Yet, little is known about individuals' actual preferences for voluntary vs. mandatory vaccination policies, and the psychological processes underlying such preferences. Objective of the present research was to investigate the development of individual preferences for voluntary and mandatory vaccination policies. METHODS: We conducted a controlled laboratory study (N = 168) using a repeated interactive vaccination game with decision-contingent monetary incentives. In each round, participants decided in favour of either a voluntary or a mandatory vaccination policy, followed by the vaccination decision (voluntary policy) or vaccination (mandatory policy) which both resulted in actual (financial) consequences. RESULTS: We observe large heterogeneity in participants' preferences for the voluntary vs. mandatory policy. Under voluntary vaccination, the preference for the mandatory policy increased with decreasing vaccination rates (and increasing risk of infection). In contrast, experiencing vaccine-adverse events under mandatory vaccination increased the preference for the voluntary policy. The latter effect was larger for individuals with a negative (vs. positive) attitude toward vaccination. Overall, as individuals gathered experiences under both the voluntary and the mandatory policy, the preference for voluntary vaccination policy increased over time. CONCLUSIONS: Individuals are more willing to accept mandatory vaccination policies when vaccination rates are low. In the long run, the occurrence of vaccine-adverse events may spark opposition to mandatory vaccination.

The willingness to vaccinate increases when vaccination protects others who have low responsibility for not being vaccinated.

Vaccination provides direct protection for the vaccinating individual and indirect protection for other, unvaccinated individuals via herd immunity. Still, some people do not get vaccinated-either because they cannot (e.g., due to health conditions) or they don't want to (e.g., due to vaccine hesitancy). We investigate whether non-vaccinators' level of responsibility for not being vaccinated affects individuals' motivation to vaccinate and, thus, to indirectly protect non-vaccinators. In Study 1 (N = 101), the intention to vaccinate increased (Cohen's d = 0.99) when non-vaccinators were described as willing but unable to get vaccinated (low responsibility) compared to when they were able but unwilling to get vaccinated (high responsibility). Study 2 (N = 297) replicated this finding with regard to vaccination behavior in an interactive vaccination (I-Vax) game (OR = 2.38). Additionally, knowing about non-vaccinators' low responsibility also increased the willingness to vaccinate compared to when there was no information on non-vaccinators' level of responsibility. Amplified levels of social welfare concerns in the case of non-vaccinators' low responsibility mediated the latter effect. This finding informs effective communication strategies for improving the vaccination rates.

[Psychological antecedents of vaccination: definitions, measurement, and interventions]. / Impfverhalten psychologisch erklären, messen und verändern.

Vaccinations are among the safest and most effective ways to prevent morbidity and mortality from severe infectious diseases - both on an individual and societal level. Despite the availability of safe and effective vaccines some people decide against vaccination, which leads to recurrent outbreaks of vaccine-preventable diseases. In order to achieve the common goals of eliminating certain infectious diseases and to protect individual health, it is necessary to understand the antecedents of (non-)vaccination.The 5C model describes five relevant psychological antecedents of vaccination: confidence, complacency (risk perceptions), constraints (barriers), calculation (extent of information search), and collective responsibility (willingness to protect the community). This contribution provides an overview of how these antecedents can be measured on an individual level and how interventions should be designed and evaluated to address the respective antecedents.Data from Germany show that structural changes to reduce practical barriers are important to improve vaccine uptake. Thus, it is also important to address aspects beyond confidence.

Behavioural consequences of vaccination recommendations: An experimental analysis.

Annual vaccination is the most effective way to prevent seasonal influenza. However, globally, the recommendations vary from country to country, ranging from universal recommendations, risk-group-specific recommendations, to no recommendation at all. Due to high diversity both in recommendation practice and country-specific preconditions, it is difficult to determine the effect of different recommendations on vaccine uptake. This incentivised laboratory experiment (N = 288) tests the behavioural consequences of different recommendations in a repeated interactive vaccination game. The participants are part of heterogeneous groups, comprised of low- and high-risk type of players. They receive either a universal, risk-group-specific or no recommendation prior to their vaccination decisions. Results show that individuals are sensitive to the recommendations. In detail, a risk-group-specific recommendation increases vaccine uptake of high-risk types. However, at the same time, it decreases vaccine uptake of low-risk types. The results imply that when the proportion of low-risk types in a population is considerably larger than the high-risk group, a risk-group-specific (vs. universal) recommendation comes at the cost of decreased social benefit of vaccination due to the overall lower vaccine uptake. Policy decision-making should therefore complement epidemiological considerations with potential positive and negative behavioural consequences of vaccination recommendations.

Vicarious experiences of long COVID: A protection motivation theory analysis for vaccination intentions.

Context: Long COVID can appear as a severe late consequence (sequela) of a COVID-19 infection, leading to the inability to work or participate in social life for an unknown amount of time. To see friends or family struggling with long COVID might influence people's risk perceptions, vaccine efficacy expectations, and self-efficacy perceptions to prevent COVID-19 and its consequences. Methods: In an online survey in August 2022, n = 989 German-speaking participants indicated whether they knew someone who suffered from long COVID illness. Four dimensions of protection motivation theory (PMT) were assessed afterwards, as well as vaccination intentions. Results: Multiple mediation analysis with participants who knew vs. didn't know someone with long COVID (n = 767) showed that knowing someone with long COVID was associated with higher perceived affective and cognitive risk of long COVID-19 as well as higher perceived vaccine efficacy. Self-efficacy, i.e., the ease to protect oneself against long COVID, was lower in participants who knew long-COVID patients. Indirect positive effects for response efficacy and affective risk suggest that vicarious experience with long COVID is associated with increased intentions to get a COVID-19 vaccine. Conclusion: The protection from long COVID through vaccination are relevant aspects for individual decisions and health communication.

Communicating diagnostic uncertainty reduces expectations of receiving antibiotics: Two online experiments with hypothetical patients.

The overprescription of antibiotics due to diagnostic uncertainty and inappropriate patient expectations influence antimicrobial resistance. This research assesses (i) whether communicating diagnostic uncertainty reduces expectations of receiving antibiotics and (ii) which communication strategies minimise unintended consequences of such communication. In two experimental online studies conducted in January and April 2023, participants read a vignette describing a doctor consultation for an ear infection and expressed their expectations of receiving antibiotics, trust in their doctor, rated the doctor's reputation and provided their intention to get a second doctor's opinion. Study 1 (N = 2213) investigated whether communicating diagnostic uncertainty and social externalities of antibiotic use (the negative social impacts of developing antibiotic resistance) decreases expectations for antibiotics and explores potential unintended consequences on the doctor-patient relationship. In Study 2 (N = 527), we aimed to replicate and extend the findings by adding specific treatment recommendations. Disclosing diagnostic uncertainty (vs. certainty) and communicating (vs. not communicating) the social externalities of antibiotic overuse reduced patients' expectations of receiving antibiotics. Yet, communicating uncertainty impaired trust in the doctor and the doctor's reputation. Combining the communication of uncertainty with specific treatment recommendations-particularly delayed antibiotic prescriptions-showed important to prevent these unintended consequences.

Understanding and reducing inappropriate antibiotic use in the context of delayed prescriptions.

OBJECTIVE: Antimicrobial resistance is a global health threat perpetuated by the overprescribing of antibiotics in primary care. One strategy to reduce antibiotic use in this setting is delayed prescribing. However, several psychological factors might undermine its effectiveness. The aim of the study was to test whether different interventions aiming at helping patients to manage diagnostic uncertainty in the period of watchful waiting promote appropriate antibiotic use. METHOD: We conducted a preregistered online experiment (N = 690 adult participants from the United Kingdom) in which we modeled delayed prescription in a decision task with behavior-contingent incentives. Participants had either a fictional viral or bacterial infection and received interventions that aimed at facilitating symptom monitoring (i.e., passive monitoring) and engaging participants in the task (i.e., active monitoring). RESULTS: Both interventions decreased antibiotic use when the disease was viral. Active monitoring was more efficient in decreasing antibiotic use than passive monitoring. CONCLUSIONS: The findings have practical implications for managing uncertainty and fostering appropriate antibiotic use in delayed prescribing situations. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Promoting prosociality toward future generations in antibiotic intake.

Understanding individuals' preferences for antibiotics can help mitigate the acceleration of antibiotic resistance. Similar to the climate crisis, individuals "today" need to appropriately use antibiotics to reduce the negative consequences of antibiotic resistance for individuals "tomorrow." We use an established-yet novel in this research field-behavioral game approach to investigate individuals' preferences for antibiotics in the face of a between-generations conflict. In an online study, we investigated whether a between-generations (vs within-generations) conflict in antibiotic intake leads to larger overuse and how to promote appropriate use of antibiotics. Results indicate that overuse in the face of a between-generations (vs within-generations) conflict increased. Eliciting empathy toward future generations in the case of a between-generations conflict decreased overuse. Findings suggest that different representations of this social dilemma can influence people's preferences for antibiotics, and that empathy-based interventions might promote appropriate antibiotic use.

Situational pathogen avoidance mediates the impact of social connectedness on preventive measures during the COVID-19 pandemic.

During the COVID-19 pandemic, physical distancing was one of the more important behaviours for reducing the spread of the virus. The present study investigated the influence on pathogen avoidance of familiarity with other people at private gatherings. Based on the social identity model of risk taking and the theory of the behavioural immune system, we assumed that greater familiarity with others would make people feel more connected with one another and decrease situational pathogen avoidance. This could result in lower perceptions of the risk of contracting COVID-19 and fewer protective behaviours. Two experiments (n1 = 1022, n2 = 994) showed that the negative influence of greater familiarity on the perceived risk of infection and protective behaviour is explained by an increased feeling of connectedness and less feeling of situational pathogen avoidance. In an additional survey, the participants (n = 23,023) rated the quality of their past social contacts. The correlational analyses showed that the familiarity of the other person was more important in explaining variance in protective behaviours than attitudes toward those behaviours or the pandemic situation itself. Understanding the process that result in an explosive increase in infection after social gatherings can improve infection control in the future.

The association between vaccination status identification and societal polarization.

Public discord between those vaccinated and those unvaccinated for COVID-19 has intensified globally. Theories of intergroup relations propose that identifying with one's social group plays a key role in the perceptions and behaviours that fuel intergroup conflict. We test whether identification with one's vaccination status is associated with current societal polarization. The study draws on panel data from samples of vaccinated (n = 3,267) and unvaccinated (n = 2,038) respondents in Germany and Austria that were collected in December 2021 and February, March and July 2022. The findings confirm that vaccination status identification (VSI) explains substantial variance in a range of polarizing attitudes and behaviours. VSI was also related to higher psychological reactance toward mandatory vaccination policies among the unvaccinated. Higher levels of VSI reduced the gap between intended and actual counterbehaviours over time by the unvaccinated. VSI appears to be an important measure for predicting behavioural responses to vaccination policies.