Fact boxes that inform individual decisions may contribute to a more positive evaluation of COVID-19 vaccinations at the population level

Explaining seasonality increases perceived effectiveness of influenza vaccination: An experimental study

BACKGROUND

Doubts regarding vaccine effectiveness may prompt people to decide against a seasonal influenza vaccination. While fact boxes show the effectiveness in terms of cases prevented, people often lack knowledge about important contextual factors, for example, why the vaccine formulation needs to be updated annually, the vaccine mechanism and relevance of the antigen-virus match. Adding such contextual information could improve effectiveness perceptions.

OBJECTIVE

In a preregistered online experiment, we tested whether explaining the seasonality's relevance and mechanisms behind influenza vaccine effectiveness affects people's perceptions of influenza vaccination. We compared two means of explanation (an additional expository text vs. a narrative offering an analogy to improve understanding of vaccine effectiveness) with a control condition simply providing effectiveness information.

DESIGN

Unvaccinated participants (N = 1554) were assigned to one of three conditions: (1) fact box only (providing the influenza vaccine's benefit-risk profile; control group), (2) fact box plus informational expository text or (3) fact box plus narrative analogy.

METHODS

After the experimental manipulations, participants rated the vaccine's effectiveness in preventing influenza disease and answered knowledge questions. Effects on perceived risk of vaccination and intention to get vaccinated were also explored.

RESULTS

Reading the expository text increased the perceived vaccine effectiveness and overall knowledge, while reading the narrative analogy only increased the perceived vaccine effectiveness compared with the control condition. All other dependent variables were similar in both text conditions.

CONCLUSIONS

Extended explanations of vaccine effectiveness can increase perceived vaccine effectiveness. The text format chosen can affect outcomes, such as vaccine-related perceptions or knowledge.

Do summaries of evidence enable informed decision-making about COVID-19 and influenza vaccination equitably across more and less disadvantaged groups? Study protocol for a multi-centre cluster randomised controlled trial of 'fact boxes' in health and social care in Germany

INTRODUCTION

Evidence summaries on the benefits and harms of treatment options support informed decisions under controlled conditions. However, few studies have investigated how such formats support decision-making across different social groups. There is a risk that only disadvantaged people will be able to make informed health decisions-possibly increasing the health equity gap. It is also unclear whether they support decision-making in the field at all. The aim of our study is to assess whether evidence summaries based on the fact box format can help people from different social groups make informed decisions about COVID-19 and influenza vaccinations, and thus reduce inequity in health communication.

METHODS AND ANALYSIS

In a multi-centre, cluster-randomised, controlled trial, health educators from usual care and outreach work in Germany will be randomised in a 1:1 ratio to provide either usual health communication plus an evidence summary ('fact box') or usual health communication. Health educators provide a flyer about COVID-19 or influenza vaccination which contains a link to an online study either with (intervention) or without (control) fact box on the reverse side. Flyer and online study will be available in Arabic, German, Turkish and Russian language. The primary outcome is informed vaccination intention, based on vaccination knowledge, attitudes, intentions and behaviour. Secondary outcomes include risk perception, decisional conflict and shared decision-making. We will use linear mixed models to analyse the influence of both individual (eg, education status) and cluster level factors and account for the expected cluster variability in realising usual health communication or the intervention. The statistical analysis plan includes the selection of appropriate measures of effect size and power calculation, assuming a sample size of 800 patients.

ETHICS AND DISSEMINATION

The trial has been approved by the Ethics Committee of the University of Potsdam, Germany (application numbers: 34/2021 and 57/2022).Results will be disseminated through peer-reviewed journals, conferences and to relevant stakeholders.

PROTOCOL VERSION

Version 6 (4 October 2024); Preprint available on Research Square: https://doi.org/10.21203/rs.3.rs-3401234/v3 TRIAL REGISTRATION NUMBER: NCT06076421.

Risk literacy: Foundational issues and its connection to risk science

A new research area is developing, risk literacy. The term "risk literacy" basically refers to one's ability to understand and evaluate risk, in order to support and make appropriate decisions. In this article, we discuss how risk literacy relates to risk analysis/science with its topics of risk fundamentals (concepts), risk understanding, risk assessments, risk characterizations, risk perception, risk communication, and risk handling (covering risk management, risk governance, and policies on risk). We question how issues and research topics addressed in risk literacy relate to risk analysis/science knowledge, particularly on risk understanding. The main conclusion of the article is that risk literacy addresses an important topic-from both a theoretical and a practical societal relevancy perspective-and brings the potential for many additional developments and further insights if the topic is better integrated with risk science knowledge more broadly.

Exploring pre-pandemic patterns of vaccine decision-making with the 5C model: results from representative surveys in 2016 and 2018

BACKGROUND

The 5C psychological antecedents of vaccination (Confidence, Complacency, Constraints, Calculation, and Collective Responsibility) facilitate understanding vaccination decisions in specific target groups as well as the general public's informational needs. This study aims to explain pre-pandemic vaccination behaviour (a) in general, (b) for specific vaccines such as influenza, and (c) for certain target groups (e.g. people over the age of 59 years, parents, healthcare workers), using the 5C model and sociodemographic variables. The intention to get an influenza vaccination was also analysed for target groups.

METHODS

The 5C, self-reported vaccination behaviour and the intention to vaccinate were collected in two representative telephone surveys in Germany - one in 2016 (n1 = 5,012) and another in 2018 (n2 = 5,054). Parents, people over the age of 59 years, chronically ill people, people with a migratory background, pregnant women and healthcare workers were target groups.

RESULTS

Overall, the 5C model had higher explanatory power than sociodemographic variables. The pattern of vaccine hesitancy slightly differed between vaccinations and target groups. Confidence in safety and effectiveness was always a significant predictor. Complacency (the underestimation of disease risks) and Constraints were significant predictors as well. Calculation (of risks and benefits) was important for influenza vaccination intentions.

CONCLUSIONS

This work builds an important benchmark for understanding potential changes in vaccine acceptance due to the pandemic. The benchmark can be used in research on potential effects of the pandemic on vaccination behaviours. Intervention designers can also use the results to understand specific audiences and their vaccination decisions.

Infographics on risks associated with COVID-19 and the willingness to get the AstraZeneca vaccine: two randomized online experiments

BACKGROUND

Germans hesitated to get vaccinated with AstraZeneca in the COVID-19 pandemic after reports of blood clots.

METHODS

In two preregistered online experiments with stratified randomization (Study 1 N = 824, Study 2: N = 1,056), we tested whether providing evidence-based benefit-risk information reduces the perceived risk of the AstraZeneca vaccine and the perceived probability of blood clots due to the AstraZeneca vaccine and increases the vaccination intention. In Study 1, participants saw no infographic (control) or one of two infographics (low vs. high exposure risk varied by the underlying incidence rates). Study 2 additionally varied the infographic design displaying the risk information (presented as table, circle icons, or manikin-like icons).

RESULTS

The infographic decreased the risk perception of the vaccine compared to no infographic (Study 1: Cohens d = 0.31, 95% CI [0.14, 0.48]; Study 2: Cohens d = 0.34, 95% CI [0.06, 0.62]), but it did not influence the perceived probability of blood clots due to the AstraZeneca vaccine (Study 2: Cohens d = 0.05, 95% CI [-0.23, 0.33]). Also, the infographic design did not affect the perceived probability of blood clots (Study 2). The vaccination intention was not affected by viewing the infographic (Study 1: Cohens d = 0.04, 95% CI [-0.13, 0.21]; Study 2: Cohens d = 0.04, 95% CI [-0.24, 0.32]) nor the presented infection rate (Study 1: Cohens d = 0.07, 95% CI [-0.09, 0.24], Study 2: Cohens d = 0.01, 95% CI [-0.12, 0.15]) but by risk perceptions, sociodemographic characteristics, confidence in the AstraZeneca vaccine, and preference for alternative vaccines.

CONCLUSIONS

The evidence-based benefit-risk information helped putting the risk of vaccinations into perspective. Nevertheless, objective risk information alone did not affect vaccination intention that was low due to the preexisting lacking vaccine confidence.

How to convince the vaccine-hesitant? An ease-of-access nudge, but not risk-related information increased Covid vaccination-related behaviors in the unvaccinated

In this study, we contrast how different benefit and harm information formats and the presence or absence of an ease-of-access nudge may facilitate COVID vaccination uptake for a sample of 620 unvaccinated Dutch adults at a timepoint when the vaccine had been widely available for more than a month. Using a 2 × 2 between-subjects factorial design, we varied the information format on mRNA COVID vaccination statistics (generic text vs. facts box) and an affirmative nudge emphasizing the ease of making a vaccination appointment (absent vs. present). We assessed the acceptance of the vaccination information provided, perceptions on the vaccination, and whether participants directly visited a COVID vaccination appointment website. Whereas the facts box did not significantly affect participants' information acceptance, vaccination attitudes, intentions, and link clicking, the affirmative nudge alongside an online link systematically increased the likelihood of clicking on the link to make a vaccination appointment. A verbal nudge emphasizing the ease of vaccine accessibility is more likely to increase vaccination uptake in an unvaccinated population than informational campaigns on vaccine effectiveness.

Protecting mass-gathering events in a pandemic with testing tracks and transparent information: an experimental study with festival guests

Objective. To enable future open-air festivals during a pandemic, model festivals tested restricted access and behavioural rules to prevent SARS-CoV-2 transmissions. However, the uptake of health-protective measures depends on informed acceptance, meaning people are more likely to follow measures if they understand their effectiveness and related disease risks. Design and main outcome measures. With a series of online surveys, we studied risk perceptions of 6,500 festival guests and the association of perceived effectiveness of protective behaviours with reported compliance. In a scenario-based online experiment (N = 1,958) among festival guests, we tested the effect of informing transparently about the risk-reducing potential of protective measures at festivals on the intention to attend hypothetical events. Results. We found that guests tended to overestimate infection risks while still perceiving them as low. Self-reported mask wearing and distancing at and around the festivals could not be associated with the understanding of the measures' effectiveness. However, in addition to protective measures themselves, providing transparent information about their absolute risk-reducing effect increased intentions to attend festivals that employ varying protective measures. Conclusion. Our findings suggest that the acceptance of protected festivals can be influenced by transparent information about the effectiveness of protective measures. This calls for further research on evidence-based public health communications to improve their impact.

Medizinische Evidenz kompetent kommunizieren

Wie alle Patienten in Deutschland sollen auch jene in der Herzchirurgie, soweit wie möglich, in die klinische Entscheidungsfindung eingebunden werden. Was möglich ist, hängt – neben Patientenvoraussetzungen – maßgeblich von den kommunikativen Fähigkeiten und Werkzeugen ab, die der beratende Arzt einsetzt, um informiertes Entscheiden auf Basis der besten verfügbaren medizinischen Erkenntnisse zu ermöglichen. Anhand von Schlüsselherausforderungen strukturiert dieser narrative Überblick Lösungsansätze für die Nutzung medizinischer Evidenz in Entscheidungsprozessen: unbestimmte Bezugsrahmen, relative Risiken, komplexe Informationen zu Entscheidungsoptionen bis hin zur Interpretation vorangehender diagnostischer Testergebnisse. Die dargestellten Lösungsansätze stellen in die Versorgung integrierbare Werkzeuge dar. Sie erfordern eine Kompetenzstärkung des Fachpersonals und qualitätsgesicherte medizinische Informationsangebote.

Vaccination Intention Following Receipt of Vaccine Information Through Interactive Simulation vs Text Among COVID-19 Vaccine-Hesitant Adults During the Omicron Wave in Germany

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, vaccine-hesitant adults presented with an interactive risk ratio simulation were more likely to show positive change in COVID-19 vaccination intention and benefit-to-harm assessment than those presented with a conventional text-based information format. These findings suggest that the interactive risk communication format can be an important tool in addressing vaccination hesitancy and fostering public trust.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study conducted online with 1255 COVID-19 vaccine-hesitant adult residents of Germany in April and May 2022, surveyed using a probability-based internet panel maintained by respondi, a research and analytics firm. Participants were randomized to 1 of 2 presentations on the benefits and adverse events associated with vaccination.

EXPOSURE

Participants were randomized to a text-based description vs an interactive simulation presenting age-adjusted absolute risks of infection, hospitalization, ICU admission, and death after exposure to coronavirus in vaccinated vs unvaccinated individuals relative to the possible adverse effects as well as additional (population-level) benefits of COVID-19 vaccination.

IMPORTANCE

Hesitancy toward COVID-19 vaccination is a major factor in stagnating uptake rates and in the risk of health care systems becoming overwhelmed.

MAIN OUTCOMES AND MEASURES

Absolute change in respondents' COVID-19 vaccination intention category and benefit-to-harm assessment category.

OBJECTIVE

To compare an interactive risk ratio simulation (intervention) with a conventional text-based risk information format (control) and analyze change in participants' COVID-19 vaccination intention and benefit-to-harm assessment.

RESULTS

Participants were 1255 COVID-19 vaccine-hesitant residents of Germany (660 women [52.6%]; mean [SD] age, 43.6 [13.5] years). A total of 651 participants received a text-based description, and 604 participants received an interactive simulation. Relative to the text-based format, the simulation was associated with greater likelihood of positive change in vaccination intentions (19.5% vs 15.3%, respectively; absolute difference, 4.2%; adjusted odds ratio [aOR], 1.45; 95% CI, 1.07-1.96; P = .01) and benefit-to-harm assessments (32.6% vs 18.0%; absolute difference, 14.6%; aOR, 2.14; 95% CI, 1.64-2.80; P < .001). Both formats were also associated with some negative change. However, the net advantage (positive - negative change) of the interactive simulation over the text-based format was 5.3 percentage points for vaccination intention (9.8% vs 4.5%) and 18.3 percentage points for benefit-to-harm assessment (25.3% vs 7.0%). Positive change in vaccination intention (but not in benefit-to-harm assessment) was associated with some demographic characteristics and attitudes to COVID-19 vaccination; negative changes were not.