Nudging toward vaccination: a systematic review

The desire of autonomy: A lever for vaccination of the elderly? Results of a qualitative study

The COVID-19 pandemic has highlighted the challenges of vaccination and the infectious risks among the elderlies. However, immunization rates for recommended vaccines in this population are insufficient in France. We aimed in this study to identify the levers and obstacles to vaccination among seniors, and to establish the arguments that could lead to some new vaccination behaviors. A qualitative survey based on 14 semi-structured interviews was conducted with people aged 65 and over, living at home in the Auvergne Rhône-Alpes region (France) from March to May 2022. The interviews were recorded, entirely transcribed, then subjected to a thematic content analysis. The results show that participants are keen to preserve their health by maintaining their physical capacity, taking regular exercise and eating a balanced diet. However, vaccination was not mentioned as a mean of preventing infectious diseases. Infections were not perceived as a cause for concern. Furthermore, the physical and cognitive consequences of infectious diseases, which could result in a loss of autonomy, were not known. These elements could be a good lever to bring hesitant elderly people to reconsider their position toward vaccination. Vaccines were not seen as a strategy to prevent loss of autonomy among elderlies. Since vaccines against influenza, COVID-19, shingles, pneumococcus have proved to be effective in protecting against cardiovascular events, this argument might be the starting point for a prevention campaign for the elderly.

The power of the family in times of pandemic: Cross-country evidence from 93 countries

The majority of the hospitalizations and deaths associated with COVID-19 occurred in people over the age of 65. In addition, previous studies have shown that intergenerational contacts played a key role in COVID-19-related infection and fatality. This paper utilized two large-scale multinational surveys to uncover the important role of family ties in infection prevention across 93 countries. Using the World Values Survey, we measured country-level family ties emphasizing respondents' view of their parents. We elicited individual willingness to uptake infection prevention measures from a panel study conducted each month in the early phase of the COVID-19 pandemic between March 2020 and July 2021. We find that in countries with stronger family ties, people show more support for non-pharmaceutical interventions and higher vaccine acceptance; moreover, young people are more supportive of mandatory vaccination. The association between strength of family ties and compliance with infection prevention measures was salient before COVID-19 vaccines became available and was persistent before the global vaccination coverage reached 25%.

Nudging Interventions on Stair Use: A Scoping Review

Stair use is a physical activity that can be incorporated into the daily lifestyle of a majority of the population, resulting in several health benefits. Nudges are increasingly used in public health interventions to encourage healthy behaviours such as physical activity in a cost-effective manner. This scoping review aimed to investigate the effect and the characteristics of nudges used on interventions to promote stair use. We reviewed the relevant literature published in PubMed, Cochrane Library, Mendeley and Google Scholar, from January 2009 to May 2022. Eligibility criteria included original studies of any type of design, written in English, targeting healthy adults, reporting nudging interventions, using elevator or escalator as comparators and defining a baseline for comparisons. Initially, 118 publications were identified, and after applying exclusion criteria, 27 articles were included in the analysis. Results showed that most of the nudging interventions had significant positive effect on stair use in several settings. The evidence from this review suggests that incorporating nudges into public health interventions can effectively promote physical activity through increased stair usage. Emphasizing prevention measures in public health interventions may contribute to better health outcomes.

Effectiveness of Catch-Up Vaccination Interventions Versus Standard or Usual Care Procedures in Increasing Adherence to Recommended Vaccinations Among Different Age Groups: Systematic Review and Meta-Analysis of Randomized Controlled Trials and Before-After Studies

BACKGROUND

To address the global challenge of vaccine hesitancy, the Strategic Advisory Group of Experts on Immunization strongly promotes vaccination reminder and recall interventions. Coupled with the new opportunities presented by scientific advancements, these measures are crucial for successfully immunizing target population groups.

OBJECTIVE

This systematic review and meta-analysis aims to assess the effectiveness of various interventions in increasing vaccination coverage compared with standard or usual care. The review will cover all vaccinations recommended for different age groups.

METHODS

In February 2022, 2 databases were consulted, retrieving 1850 studies. Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, 79 manuscripts were included after the assessment phase. These comprised 46 trials/randomized controlled trials (RCTs) and 33 before-after studies. A meta-analysis using a random-effects model was performed with STATA software (version 14.1.2). The selected outcome was the risk ratio (RR) of vaccination coverage improvement effectiveness. Additionally, meta-regression analyses were conducted for the included manuscripts.

RESULTS

The analyses showed an overall efficacy of RR 1.22 (95% CI 1.19-1.26) for RCTs and RR 1.70 (95% CI 1.54-1.87) for before-after studies when considering all interventions cumulatively. Subgroup analyses identified multicomponent interventions (RR 1.58, 95% CI 1.36-1.85) and recall clinical interventions (RR 1.24, 95% CI 1.17-1.32) as the most effective in increasing vaccination coverage for RCTs. By contrast, educational interventions (RR 2.13, 95% CI 1.60-2.83) and multicomponent interventions (RR 1.61, 95% CI 1.43-1.82) achieved the highest increases for before-after studies. Meta-regression analyses indicated that the middle-aged adult population was associated with a higher increase in vaccination coverage (RCT: coefficient 0.54, 95% CI 0.12-0.95; before-after: coefficient 1.27, 95% CI 0.70-1.84).

CONCLUSIONS

Community, family, and health care-based multidimensional interventions, as well as education-based catch-up strategies, effectively improve vaccination coverage. Therefore, their systematic implementation is highly relevant for targeting undervaccinated population groups. This approach aligns with national vaccination schedules and aims to eliminate or eradicate vaccine-preventable diseases.

Increasing vaccination coverage among healthcare workers: Active call and mandatory laws. Data from a large general hospital in Southern Italy

Influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are respiratory pathogens which significantly impact healthcare systems. Seasonal vaccination is recommended for all healthcare workers (HCWs) to reduce the risk for both operators and patients. Puglia, a region in Southern Italy, has been enforcing since 2018 a law mandating influenza vaccination in healthcare workers. However, vaccination coverages for this category have always been suboptimal. Our study tests the effectiveness of an active recall intervention on vaccination coverage for influenza and SARS-CoV-2 in the HCWs of a large Apulian hospital (Southern Italy). During the 2023-2024 influenza vaccination season, unvaccinated HCWs of Bari's Policlinico General Hospital were contacted. The e-mail reminded them of a regional law mandating influenza vaccination to all HCWs and offered an appointment for vaccination. SARS-CoV-2 vaccination was also offered. In 2022-2023, 43.16 % of HCWs were vaccinated against influenza and 21.87 % against SARS-CoV-2. Coverage changed during the 2023-2024 season to 54.11 % and 13.58 %, respectively. A regression model showed that vaccination uptake's increase was associated with the e-mail reception and with the operator being a physician vs. non-medical personnel. On the contrary, subjects who received the e-mail did not show an increased SARS-CoV-2 vaccination uptake, which was on the contrary influenced by the worker's age, sex, job title, and area of risk. Our soft-mandate intervention was effective in increasing vaccination uptake by HCWs. Communication with a trained specialist was probably useful, and the possibility to access vaccination services with dedicated appointments increased convenience. Mandatory vaccination policies and active recall seem to synergically impact vaccination uptake.

Financial incentives for sanitation take-up: A randomized control trial in rural Vietnam

This study assesses the impact of financial incentives on hygienic latrine ownership by poor/near-poor households in Vietnam. Rural communes were randomly assigned to a control group and three treatment arm groups: (T1) a rebate for households that installed a hygienic latrine; (T2) a financial reward for commune governments if the proportion of hygienic latrines in their commune increased by 30 percentage points; (T3) both a household rebate and a commune reward. We find a strong and positive effect from the household rebate (treatment arms 1 and 3) but an insignificant effect from the commune reward (treatment arm 2) on household ownership of a septic tank latrine. Our analysis provides suggestive evidence that microcredit is a channel through which a rebate encourages the installation of septic tank latrines. We also find that treatment arm 3 increases people's knowledge regarding sanitation and the availability of water and soap for handwashing within households.

Knowledge, attitudes, and intentions regarding COVID-19 vaccination in the general population and the effect of different framing messages for a brief video on intentions to get vaccinated among unvaccinated individuals in the United States during July 2021

OBJECTIVE

To identify knowledge, attitudes, and beliefs (KABs) associated with COVID-19 vaccination intentions and assess the impact of vaccine-promoting messages on vaccination intentions.

METHODS

Our nationally representative survey measured KABs of COVID-19 vaccination and incorporated a randomized experiment to assess the impact of different framing messages for a video encouraging vaccination intentions among unvaccinated adults in the US. Multivariable multinomial logistic regression models were fitted to investigate the relationships of KABs, trust in public health authorities (PHAs), and vaccine confidence with vaccination intentions. Difference-in-difference estimation was conducted to assess the impact of framing messages for a video on unvaccinated individuals' vaccination intentions.

RESULTS

We observed that people with increasingly favorable vaccine KABs, trust in PHAs, and vaccine confidence were more likely to be vaccinated or intend to get vaccinated against COVID-19. Difference-in-difference estimates indicated a positive impact of exposure to the video on vaccination intentions while framing messages in some cases appeared to lower vaccination intentions. Associations between the video and vaccination intentions were more pronounced among Black/African American and Hispanic/Latinx populations and Democrats; however, associations did not vary by trust in PHAs or vaccine confidence.

CONCLUSION

Videos that encourage people to get vaccinated may provide an efficient approach to nudge vaccine-hesitant individuals towards getting vaccinated. However, framing messages may negatively impact vaccination intentions and need to be developed carefully.

PRACTICE IMPLICATIONS

This study provides solid experimental evidence for the importance of tailoring message framing to the characteristics and experience of the audience, while cautioning potential negative impacts of framing that does not match its intended audience. Our findings are applicable to health communication strategies on the population level, such as mass media campaigns, and the use of framing for messages to encourage vaccination but may also be informative for healthcare professionals consulting hesitant individuals about COVID-19 vaccinations.

A World without Measles and Rubella: Addressing the Challenge of Vaccine Hesitancy

The worldwide elimination of measles and rubella is feasible, but not without overcoming the substantial challenge of vaccine hesitancy. This challenge is complicated by the spread of misinformation and disinformation fueled by rapidly progressing technologies and evolving forms of online communication. The recent COVID-19 pandemic has only added further complexity to this challenge. However, considerable progress has been made in understanding the scope of the problem and the complex factors that influence vaccine hesitancy. Our understanding of evidence-based strategies for addressing vaccine hesitancy has grown significantly, including evidence for effective communication and behavioral interventions. In this article, we review measles and rubella vaccines and vaccine hesitancy. We then provide an overview of evidence-based strategies for addressing vaccine hesitancy, including communication strategies and behavioral interventions. This article is relevant to healthcare professionals, health system leaders, public health professionals, policymakers, community leaders, and any individuals who have a role in addressing vaccine hesitancy in their communities. Finally, we review future directions and major areas of research need.

Anti-Herpes Zoster Vaccination of Fragile Patients in Hospital Setting: A Nudge Intervention in Italy

BACKGROUND

A nudge intervention against Herpes Zoster, created and implemented in Italy, is presented in order to administer the Shingrix vaccine on a sample of frail patients, as required by the National Prevention Plan. Individual and contextual factors associated with vaccine adherence were investigated.

METHOD

300 frail adult subjects underwent a full vaccine cycle with recombinant-Shingrix vaccine (RZV vaccine). Hospital Presidia of the Salerno University Hospital Authority, a Hospital Presidium of the Salerno Local Health Authority, and the Public Health Laboratory of the University of Salerno (Campania) participated in the intervention. An ad hoc questionnaire was administered with the following scales: EQ-5D, PSS-10, MSPSS, and representations of HZ and its consequences.

RESULTS

Some variables, such as peer support, doctor-patient relationship, level of education, and perception of health, are important in vaccine adherence and information processing. The following factors emerged from the factor analysis: Trust in collective knowledge and collective responsibility (F1); beliefs about virus risk and vaccine function (F2); information about virus and symptomatology (F3); and vaccine distrust (F4). Factor 4 correlates negatively with social support indices (R = -0.363; p < 0.001). There is a significant relationship between factor 3 and satisfaction with national information campaigns (F = 3.376; gdl = 5; p-value = 0.006).

CONCLUSIONS

Future vaccination campaigns should be built with the aim of personalizing information and developing contextualized strategies, starting from understanding the stakeholders involved, cultural contexts, and organizational settings.

Thinking about default enrollment lowers vaccination intentions and public support in G7 countries

Policymakers often face a conundrum between being transparent about policies and ensuring that those policies are effective. This challenge is particularly relevant for behavioral nudges, which are not usually disclosed. Rather than avoiding transparency, we suggest that policymakers encourage citizens to reflect on nudges to help them understand their own views and align those views with their behaviors. Using data from an online survey experiment with 24,303 respondents in G7 countries, we examine the impact of reflection on a hypothetical default nudge policy for COVID-19 booster appointments. Contrary to expectations, participants say they would be less likely to get the booster when automatically enrolled compared with a control condition. Similarly, encouraging citizens to think about the status quo (baseline) policy also reduces intentions for boosters. These interventions have no effect on approval of the policy. Further, encouraging people to think about automatic enrollment decreases approval of the policy and further decreases their intentions to get vaccinated. These findings suggest that reflection on a nudge can increase backlash from a nudge and also elicit policy disapproval, thereby aligning policy support with behavioral intentions.

"How" Versus "Why" Messaging to Increase Uptake of Booster Vaccination Against COVID-19: Results of a Pragmatic Randomized Trial

BACKGROUND

Messages aimed at increasing uptake of vaccines have been modestly successful, perhaps in part because they often focus on why individuals should receive a vaccine. Construal Level Theory posits that messages emphasizing "how" to get a vaccine may be more effective at encouraging vaccination than emphasizing "why." This message framing may be particularly important for COVID-19 booster acceptance.

OBJECTIVE

To determine if pre-visit patient portal messages designed using Construal Level Theory increase rates of COVID-19 booster vaccination.

DESIGN AND INTERVENTIONS

This 3-arm randomized trial was conducted across three large, diverse primary care clinics in Massachusetts between February and May 2022, testing the impact of "how" versus "why" framed pre-visit messages versus no messages ("usual care"). Messages were sent by patient portal two business days before a visit.

PARTICIPANTS

Adults with upcoming primary care visits who had electronic health record evidence of receiving their initial COVID-19 vaccination series but not a booster dose.

MAIN MEASURES

Receipt of a COVID-19 booster vaccination after the message was sent through the visit date (primary outcome) or 6 weeks (secondary outcome).

KEY RESULTS

A total of 3665 patients were randomized (mean age: 53.5 years (SD: 17.3), 59% female, 65.2% White, 26.6% Hispanic), with 1249 to "how" 1199 to "why," and 1217 to usual care arms. Except for clinic and preferred language, characteristics were well balanced across arms. Rates of COVID-19 booster were 13.6% (usual care), 11.7% ("how") (odds ratio (OR) "how" vs usual care: 0.87, 95%CI: 0.67-1.14), and 13.7% ("why") ("why" vs usual care: OR: 1.01, 95%CI: 0.81-1.28). At 6 weeks, "why" outperformed "how" for vaccination (OR: 1.26, 95%CI: 1.06-1.49), with no difference versus usual care.

CONCLUSIONS

We found no differences on visit booster receipt after single pre-visit portal messages designed using Construal Level Theory. Further studies to identify effective messaging interventions are needed, especially as additional doses are recommended.

CLINICAL TRIAL REGISTRATION

This trial is registered at clinicaltrials.gov, ID: NCT04871776 . Initial release occurred 04/30/2021.

Strategies for Improving Vaccine Communication and Uptake

Vaccines have led to a significant decrease in rates of vaccine-preventable diseases and have made a significant impact on the health of children. However, some parents express concerns about vaccine safety and the necessity of vaccines. The concerns of parents range from hesitancy about some immunizations to refusal of all vaccines. This clinical report provides information about the scope and impact of the problem, the facts surrounding common vaccination concerns, and the latest evidence regarding effective communication techniques for the vaccine conversation. After reading this clinical report, readers can expect to: Understand concepts and underlying determinants of vaccine uptake and vaccine hesitancy.Understand the relationship between vaccine hesitancy and costs of preventable medical care.Recognize and address specific concerns (eg, vaccine safety) with caregivers when hesitancy is present.

Nudging Public Health Behaviors to Prevent COVID-19: A Systematic Review

Many countries have implemented strict preventive measures and mandatory policies to curb virus transmission during the COVID-19 pandemic. Some have adopted softer approaches, such as nudge-based intervention, to influence public health behavior. This systematic review, conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 guidelines, aims to determine if the nudge-based intervention can effectively influence people's preventive behavior during the early period of the COVID-19 pandemic. The review indicated an overall positive outcome, but results were mixed as nudge-based interventions substantially depended on the situational context. While the review found that the nudging technique that presents and conveys decision-related information was essential to nudging people, a secondary nudge would often applied to deliver the interventions. In addition, there was no indication of an ideal nudge technique that would be effective in most situations. Conversely, our findings indicate that the nudge would likely suffer from habituation after repeated intervention or backfire due to inappropriate use of nudges. Also, the ceiling effect would inhibit any nudge influences regardless of the technique(s) used. In sum, the results and the applicability of nudge-based interventions were mixed, highlighting the need for further research to advance the theory and practical developments.

Nudging towards COVID-19 and influenza vaccination uptake in medically at-risk children: EPIC study protocol of randomised controlled trials in Australian paediatric outpatient clinics

INTRODUCTION

Children with chronic medical diseases are at an unacceptable risk of hospitalisation and death from influenza and SARS-CoV-2 infections. Over the past two decades, behavioural scientists have learnt how to design non-coercive 'nudge' interventions to encourage positive health behaviours. Our study aims to evaluate the impact of multicomponent nudge interventions on the uptake of COVID-19 and influenza vaccines in medically at-risk children.

METHODS AND ANALYSES

Two separate randomised controlled trials (RCTs), each with 1038 children, will enrol a total of approximately 2076 children with chronic medical conditions who are attending tertiary hospitals in South Australia, Western Australia and Victoria. Participants will be randomly assigned (1:1) to the standard care or intervention group. The nudge intervention in each RCT will consist of three text message reminders with four behavioural nudges including (1) social norm messages, (2) different messengers through links to short educational videos from a paediatrician, medically at-risk child and parent and nurse, (3) a pledge to have their child or themselves vaccinated and (4) information salience through links to the current guidelines and vaccine safety information. The primary outcome is the proportion of medically at-risk children who receive at least one dose of vaccine within 3 months of randomisation. Logistic regression analysis will be performed to determine the effect of the intervention on the probability of vaccination uptake.

ETHICS AND DISSEMINATION

The protocol and study documents have been reviewed and approved by the Women's and Children's Health Network Human Research Ethics Committee (HREC/22/WCHN/2022/00082). The results will be published via peer-reviewed journals and presented at scientific meetings and public forums.

TRIAL REGISTRATION NUMBER

NCT05613751.

The role of vaccine status homophily in the COVID-19 pandemic: a cross-sectional survey with modelling

BACKGROUND

Vaccine homophily describes non-heterogeneous vaccine uptake within contact networks. This study was performed to determine observable patterns of vaccine homophily, as well as the impact of vaccine homophily on disease transmission within and between vaccination groups under conditions of high and low vaccine efficacy.

METHODS

Residents of British Columbia, Canada, aged ≥ 16 years, were recruited via online advertisements between February and March 2022, and provided information about vaccination status, perceived vaccination status of household and non-household contacts, compliance with COVID-19 prevention guidelines, and history of COVID-19. A deterministic mathematical model was used to assess transmission dynamics between vaccine status groups under conditions of high and low vaccine efficacy.

RESULTS

Vaccine homophily was observed among those with 0, 2, or 3 doses of the vaccine. Greater homophily was observed among those who had more doses of the vaccine (p < 0.0001). Those with fewer vaccine doses had larger contact networks (p < 0.0001), were more likely to report prior COVID-19 (p < 0.0001), and reported lower compliance with COVID-19 prevention guidelines (p < 0.0001). Mathematical modelling showed that vaccine homophily plays a considerable role in epidemic growth under conditions of high and low vaccine efficacy. Furthermore, vaccine homophily contributes to a high force of infection among unvaccinated individuals under conditions of high vaccine efficacy, as well as to an elevated force of infection from unvaccinated to suboptimally vaccinated individuals under conditions of low vaccine efficacy.

INTERPRETATION

The uneven uptake of COVID-19 vaccines and the nature of the contact network in the population play important roles in shaping COVID-19 transmission dynamics.

Interactive Narrative-Based Digital Health Interventions for Vaccine Communication: Protocol for a Scoping Review

BACKGROUND

Interactive narrative-based digital health interventions hold promise for effectively addressing the complex determinants of vaccine hesitancy and promoting effective communication across a wide range of settings and vaccine types. Synthesizing evidence related to the implementation and evaluation of these interventions could offer valuable perspectives for shaping future strategies in vaccine communication. Prior systematic and scoping reviews have examined narrative-based vaccine communication interventions but not the inclusion of interactivity in such interventions.

OBJECTIVE

The overall objective of the scoping review is to summarize the evidence on the use of interactive narrative-based digital health interventions for vaccine communication. Specific research questions focus on describing the use of interactive narrative-based digital health interventions (RQ1), describing evaluations of the impact of interactive narrative-based digital health interventions on promoting vaccine uptake (RQ2), and factors associated with their implementation (RQ3).

METHODS

A detailed search string will be used to search the following databases for records that are relevant to the review questions: PubMed, Embase, Scopus, Web of Science, CINAHL, and PsycINFO. Two reviewers will independently screen the titles and abstracts of identified records against the predefined eligibility criteria. Subsequently, eligible records will undergo comprehensive full-text screening by 2 independent reviewers to assess their relevance to review questions. A data charting tool will be developed and used to extract relevant information from the included articles. The extracted information will be analyzed following the review questions and presented as a narrative summary. Tabular or graphical representations will be used to display review findings, as relevant.

RESULTS

Public health informationists were consulted to develop the detailed search strategy. The final search string comprised terms related to narrative communication, digital health, and vaccines. The search string was customized to each proposed publication database and implemented on April 18, 2023. A total of 4474 unique records were identified using the search strategy and imported into the Covidence (Veritas Health Innovation Ltd) review management software for title and abstract screening. Title and abstract screening of identified records are ongoing as of December 29, 2023.

CONCLUSIONS

To our knowledge, this will be the first scoping review to investigate the features of interactive narrative-based digital health interventions and their role in vaccine communication. The goal of this study is to provide a comprehensive overview of the current research landscape and identify prevailing gaps in knowledge. The findings will provide insights for future research and development of novel applications of interactive narrative-based digital health vaccine communication interventions.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51137.

Behavioural evidence on COVID-19 vaccine uptake

OBJECTIVES

The World Health Organization has declared that COVID-19 is no longer a public health emergency of international concern. Nevertheless, it remains a public health issue, and seasonal vaccinations, at the same time of year as influenza vaccinations, will be necessary. When the first vaccines were administered in 2020, decision-makers had to make assumptions about the best methods to communicate and administer vaccines to increase uptake. Now, a body of evidence can inform these decisions.

STUDY DESIGN

A narrative review written by three behavioural scientists who design research for policy.

METHODS

We searched the PubMed database for: (i) reviews of interventions to increase uptake of COVID-19 or influenza vaccines and (ii) empirical studies on uptake of COVID-19 and influenza vaccines. In addition, registered trials gathered by a Cochrane scoping review of interventions to increase uptake of COVID-19 vaccines were searched for updated results.

RESULTS

Results centre around two aspects of a vaccination campaign of interest to policymakers: communication and administration. Results suggest that communications highlighting the personal benefits of vaccination are likely to be more effective than those highlighting collective benefits. The efficacy of vaccination may be underestimated and stressing efficacy as a strong personal benefit may increase uptake. Keeping vaccines free, sending personalised messages, reminders and prebooked appointment times may also increase uptake.

CONCLUSIONS

There is now a body of evidence from behavioural science that suggests how vaccination campaigns for COVID-19 can be structured to increase uptake. These recommendations may be useful to policymakers considering seasonal vaccination campaigns and to researchers generating hypotheses for country-specific trials.

Effectiveness of interventions to increase healthcare workers' adherence to vaccination against vaccine-preventable diseases: a systematic review and meta-analysis, 1993 to 2022

BackgroundVaccination adherence among healthcare workers (HCWs) is fundamental for the prevention of vaccine-preventable diseases (VPDs) in healthcare. This safeguards HCWs' well-being, prevents transmission of infections to vulnerable patients and contributes to public health.AimThis systematic review and meta-analysis aimed to describe interventions meant to increase HCWs' adherence to vaccination and estimate the effectiveness of these interventions.MethodsWe searched literature in eight databases and performed manual searches in relevant journals and the reference lists of retrieved articles. The study population included any HCW with potential occupational exposure to VPDs. We included experimental and quasi-experimental studies presenting interventions aimed at increasing HCWs' adherence to vaccination against VPDs. The post-intervention vaccination adherence rate was set as the main outcome. We included the effect of interventions in the random-effects and subgroup meta-analyses.ResultsThe systematic review considered 48 studies on influenza and Tdap vaccination from database and manual searches, and 43 were meta-analysed. A statistically significant, positive effect was seen in multi-component interventions in randomised controlled trials (relative risk (RR) = 1.37; 95% CI: 1.13-1.66) and in observational studies (RR = 1.43; 95% CI: 1.29-1.58). Vaccination adherence rate was higher in community care facilities (RR = 1.58; 95% CI: 1.49-1.68) than in hospitals (RR = 1.24; 95% CI: 0.76-2.05).ConclusionInterventions aimed at increasing HCWs' adherence to vaccination against VPDs are effective, especially multi-component ones. Future research should determine the most effective framework of interventions for each setting, using appropriate study design for their evaluation, and should compare intervention components to understand their contribution to the effectiveness.

Relationship between vaccine hesitancy and vaccination behaviors: Systematic review and meta-analysis of observational studies

BACKGROUND

Vaccination is crucial for prevention of infectious diseases, and identification of the impact of vaccine hesitancy on vaccination programs is crucial for early intervention and formulation of policies to alleviate vaccine hesitancy. The aim of this systematic review was to explore the relationship between vaccine hesitancy and negative vaccination behavior globally.

METHODS

We searched for observational studies in various databases. We conducted a meta-analysis using pooled odds ratios (OR) and 95 % confidence intervals (CI), performed meta regression and subgroup analysis to explore the role factors such as location and individual characteristics on the association between vaccine hesitancy and vaccination behavior.

RESULTS

A total of 46 articles were included in systematic analysis and 34 articles were included in the meta-analysis. The systematic analysis comprised 162,601 samples, whereas the meta-analysis included 147,554 samples. The meta-analysis showed that a higher rate of vaccine hesitancy was associated with an increased likelihood of adverse vaccination behaviors (all adverse behaviors: OR = 1.50, 95 % CI, 1.33-1.70, P < 0.001; unvaccinated: OR = 1.48, 95 % CI, 1.29-1.70, P < 0.001; vaccine delay: OR = 2.61, 95 % CI, 1.97-3.44, P < 0.001). The meta-regression results indicated that the heterogeneity observed was mainly from sample selection methods, age of vaccinees and the health status of participants. The results showed that parents of minor vaccinees or without high-risk health status had a higher association between vaccine hesitancy and vaccine uptake compared with populations exposed to higher health risks or adult vaccinees.

CONCLUSION

The findings provide evidence on the association between vaccine hesitancy and adverse vaccination behaviors. The results showed that these population-specific factors should be considered in future research, and during formulation of interventions and implementation of policies to improve vaccination uptake.

Heuristics in vaccination Decision-Making for newly developed Vaccines: Understanding the public's imitative behavior

This study aims to investigate the extent to which the public engages in imitative behavior in their vaccination decisions for newly developed vaccines in the Chinese context. Given the crucial role of newly developed vaccines in preventing and controlling the COVID-19 pandemic, a better understanding of how people make decisions about vaccination with new vaccines is important for overcoming vaccine hesitation and promoting widespread adoption of the vaccines. Our results indicate that the public's decision-making about the newly developed vaccine is influenced by a range of heuristics, including a privileged information heuristic, competence heuristic, and consensus heuristic. Specifically, individuals are more likely to imitate the vaccination behavior of those with privileged information, such as insiders, and those with perceived competence in the field, such as experts. Our findings also demonstrate the impact of majority influence, as the popularity of new vaccines leads to an increase in vaccination uptake through herd behavior. Our data highlights the importance of the first movers who are insiders with privileged information or experts with competence, as their behavior can significantly shape the vaccination decisions of others. Our study provides valuable insights into the complex interplay of heuristics and imitative behavior in vaccination decision-making for newly developed vaccines.

A synthesis of evidence for policy from behavioural science during COVID-19

Scientific evidence regularly guides policy decisions1, with behavioural science increasingly part of this process2. In April 2020, an influential paper3 proposed 19 policy recommendations ('claims') detailing how evidence from behavioural science could contribute to efforts to reduce impacts and end the COVID-19 pandemic. Here we assess 747 pandemic-related research articles that empirically investigated those claims. We report the scale of evidence and whether evidence supports them to indicate applicability for policymaking. Two independent teams, involving 72 reviewers, found evidence for 18 of 19 claims, with both teams finding evidence supporting 16 (89%) of those 18 claims. The strongest evidence supported claims that anticipated culture, polarization and misinformation would be associated with policy effectiveness. Claims suggesting trusted leaders and positive social norms increased adherence to behavioural interventions also had strong empirical support, as did appealing to social consensus or bipartisan agreement. Targeted language in messaging yielded mixed effects and there were no effects for highlighting individual benefits or protecting others. No available evidence existed to assess any distinct differences in effects between using the terms 'physical distancing' and 'social distancing'. Analysis of 463 papers containing data showed generally large samples; 418 involved human participants with a mean of 16,848 (median of 1,699). That statistical power underscored improved suitability of behavioural science research for informing policy decisions. Furthermore, by implementing a standardized approach to evidence selection and synthesis, we amplify broader implications for advancing scientific evidence in policy formulation and prioritization.

Sharpening clinical decision support alert and reminder designs with MINDSPACE: A systematic review

BACKGROUND

Clinical decision support (CDS) alerts and reminders aim to influence clinical decisions, yet they are often designed without considering human decision-making behaviour. While this behaviour is comprehensively described by behavioural economics (BE), the sheer volume of BE literature poses a challenge to designers when identifying behavioural effects with utility to alert and reminder designs. This study tackles this challenge by focusing on the MINDSPACE framework for behaviour change, which collates nine behavioural effects that profoundly influence human decision-making behaviour: Messenger, Incentives, Norms, Defaults, Salience, Priming, Affect, Commitment, and Ego.

METHOD

A systematic review searching MEDLINE, Embase, PsycINFO, and CINAHL Plus to explore (i) the usage of MINDSPACE effects in alert and reminder designs and (ii) the efficacy of those alerts and reminders in influencing clinical decisions. The search queries comprised ten Boolean searches, with nine focusing on the MINDSPACE effects and one focusing on the term mindspace.

RESULTS

50 studies were selected from 1791 peer-reviewed journal articles in English from 1970 to 2022. Except for ego, eight of nine MINDSPACE effects were utilised to design alerts and reminders, with defaults and norms utilised the most in alerts and reminders, respectively. Overall, alerts and reminders informed by MINDSPACE effects showed an average 71% success rate in influencing clinical decisions (alerts 73%, reminders 69%). Most studies utilised a single effect in their design, with higher efficacy for alerts (64%) than reminders (41%). Others utilised multiple effects, showing higher efficacy for reminders (28%) than alerts (9%).

CONCLUSION

This review presents sufficient evidence demonstrating the MINDSPACE framework's merits for designing CDS alerts and reminders with human decision-making considerations. The framework can adequately address challenges in identifying behavioural effects pertinent to the effective design of CDS alerts and reminders. The review also identified opportunities for future research into other relevant effects (e.g., framing).

How to increase COVID-19 vaccination among a population with persistently suboptimal vaccine uptake? Evidence from the North Macedonia mobile vaccination and public health advice caravan

Over three years since the first COVID-19 vaccine was approved, many countries still have suboptimal vaccination rates despite holding great amounts of vaccines. Overall, there is little evidence on which policies are more effective to encourage vaccination, particularly in countries where a large share of the population remains unvaccinated. In this study, we examine the effectiveness of a community-based intervention carried out in March 2022 in North Macedonia, a country with a large and persistent share of the population that remains unvaccinated. The intervention, spearheaded by the Ministry of Health and supported by the World Health Organization and UNICEF, consisted of a mobile caravan offering vaccination and public health advice to different locations across the country on different days. Results from our staggered difference-in-difference model show that the mobile vaccination caravan increased daily vaccination rates by 7.7 vaccines per 100,000 inhabitants during the three weeks after the day of the caravan visit. This corresponds to a 35 % increase with respect to pre-intervention vaccination rates. We estimate a cost-effectiveness of 25.4 US dollars (USD) per additional vaccination induced. These results point to mobile caravan vaccines as an effective and cost-effective strategy to increase COVID-19 vaccination rates, even in a context of persistently suboptimal uptake.

Sociodemographic factors and attitudes associated with Australian parental acceptance of paediatric COVID-19 vaccination

INTRODUCTION

The COVID-19 vaccine coverage among children in countries where COVID-19 vaccines are recommended has been suboptimal. Conflicting information in the media leads to parental anxiety and confusion around COVID-19 vaccination in children. The scepticism expressed by certain experts regarding the importance of COVID-19 vaccines in children has also had a negative impact on parental attitudes towards COVID-19 vaccination. This study aimed to understand parental concerns and preferences for paediatric COVID-19 vaccination, and identify potential vaccination promotion ("nudge") interventions to optimise paediatric COVID-19 vaccine uptake.

METHODS

Mixed methods including Focus Group Discussions and a Discrete Choice Experiment survey were used. The Discrete Choice Experiment survey design was based on a literature review and the findings of Focus Group Discussions. The study was conducted on a nationally representative sample of parents in Australia.

RESULTS

In total, 1039 parents participated in the study. Parents showed strong preferences for a COVID-19 vaccine with lower risk of serious side effects and longer protection duration, followed by higher vaccine effectiveness and delivery via oral tablets. Promotion strategies were similarly preferred by parents. Latent class logit analysis identified three groups, interpretable as COVID-19 vaccine "accepters (35.3%)", "deliberators (31.7%)", and "rejecters (33.1%)". The "deliberators" composed of more parents, residing in metropolitan areas, having concerns about vaccine effectiveness, and believing that disease risks outweigh vaccine benefits than the "accepters". The "rejecters" were more likely to not be vaccinated themselves, and generally have less trust in vaccines than the "accepters". The "deliberators" and "rejecters" were less likely to be parents aged ≥25 years and complete final year of high school than the "accepters".

CONCLUSIONS

Parents' sociodemographic factors and vaccine perceptions were associated with different levels of acceptance toward paediatric COVID-19 vaccination, which may help to better understand how to "nudge" vaccine hesitancy.

Role of leadership and incentive-based programs in addressing vaccine hesitancy in India

The current study goes beyond the popular 5Cs model of vaccine hesitancy to explore perceived social norms, role of leadership and the role of incentive-based intervention for improving the likelihood of vaccination, in a population-representative sample of adults in India (N = 1129). We investigated differences in socio-demographic status, perceived descriptive norms like vaccine behaviours, beliefs, experience and perceived injunctive norms like community and political leadership within the context of the COVID-19 pandemic are related to vaccination. Further, we examined the role of incentive-based intervention as a potentially salient predictor of adults' vaccine uptake. The study is based on a cross-sectional survey conducted in July-November 2021, which included questions about impacts of pandemic collected by phone call interview from adults' beneficiaries of Government free food schemes, across 11 states in India. The data include 81 % vaccinated and 19 % vaccine hesitant participants, with a higher proportion of business or self-employed (53.1 %) as vaccine hesitant. We performed the t-test to assess the variation between vaccinated and vaccine hesitant adults, and Exploratory Factor Analysis to uncover the underlying dimension of vaccine hesitancy. Subsequently, Binary Logistic Regression model probed the factors associated with likelihood of vaccination uptake. In contrast to the prevailing evidence, results demonstrated community and political leadership has significant negative impact on vaccination (p-value < 0.06, 95 % CI, 0.57-1.01). Incentive-based intervention offer a vital leverage to enhance positive attitude towards vaccination (p-value < 0.05, 95 % CI, 1.01-1.80). The results thus broadly highlight the limited role of political and community leaders in leveraging their influence on vaccination, the role of timely, accurate information, applications of telemedicine as an important tool to provide healthcare and the need for optimal design of incentive-based vaccination programs recommended by trusted sources.

Behavioral interventions for vaccination uptake: A systematic review and meta-analysis

BACKGROUND

Human behavior and more specifically behavioral insight-based approaches to vaccine uptake have often been overlooked. While there have been a few narrative reviews indexed in Medline on behavioral interventions to increase vaccine uptake, to our knowledge, none have been systematic reviews and meta-analyses covering not just high but also low-and-middle income countries.

METHODS

We included 613 studies from the Medline database in our systematic review and meta-analysis categorizing different behavioral interventions in 9 domains: education campaigns, on-site vaccination, incentives, free vaccination, institutional recommendation, provider recommendation, reminder and recall, message framing, and vaccine champion. Additionally, considering that there is variability in the acceptance of vaccines among different populations, we assessed studies from both high-income countries (HICs) and low- to middle-income countries (LMICs), separately.

FINDINGS

Our results showed that behavioral interventions can considerably improve vaccine uptake in most settings. All domains that we examined improved vaccine uptake with the highest effect size associated with provider recommendation (OR: 3.4 (95%CI: 2.5-4.6); Domain: motivation) and on-site vaccination (OR: 2.9 (95%CI: 2.3-3.7); Domain: practical issues). While the number of studies conducted in LMICs was smaller, the quality of studies was similar with those conducted in HICs. Nevertheless, there were variations in the observed effect sizes.

INTERPRETATION

Our findings indicate that "provider recommendation" and "on-site vaccination" along with other behavioral interventions can be employed to increase vaccination rates globally.

Using behavioral insights to increase the demand for childhood vaccination in low resource settings: Evidence from a randomized controlled trial in Lebanon

Objective

Lebanon has historically maintained high immunization coverage rates for most routine vaccines. However, an increase in poverty rates coupled with an influx of over a million refugees posed significant challenges to the national immunization program. In response, an accelerated immunization activities (AIA) program, encompassing community-based outreach and referral activities, was launched to increase the demand for childhood vaccination through the public healthcare system. Despite this effort, uptake among refugee and host community households remained low, resulting in pockets of low immunization coverage rates. This study investigates the barriers that prevent households in low coverage areas from vaccinating their children, and evaluates a behavior change intervention designed to overcome the identified social, perceptual, and cognitive barriers.

Methods

Households with un- or under-vaccinated children were recruited from seven cadastres with low immunization coverage rates. A mixed methods approach, including stakeholder interviews and field observations, was employed to identify the main barriers to vaccination. Thereafter, a cluster randomized trial was conducted to evaluate the impact of a visual planning aid comprising five behavior change techniques (nudges) on vaccine uptake.

Results

A total of 12,332 un- or under-vaccinated children from 6160 households (3045 (49.4%) control households; 3115 (50.6%) treated households) were reached during the trial. The observed vaccination rates were 13.5% and 20.2% for control and treated households, respectively. This represents a 6.7 percentage points increase in the likelihood of a treated household to vaccinate at least one child, compared to the control group. At least 390 additional children benefited from life-saving vaccines due to the behavioral intervention.

Conclusions

This study highlights the importance of integrating behavioral insights into vaccination campaigns and programs, especially in low resource settings, to ensure that more children can benefit from life-saving vaccines.

Examining spatial variation for immunisation coverage in pregnant women: A nationwide and geospatial retrospective cohort study in Aotearoa New Zealand

BACKGROUND

Maternal influenza and pertussis immunisation is crucial for protecting mothers during pregnancy and their babies in the first weeks of life against severe disease. We examined geospatial variation in maternal immunisation coverage among pregnant women in Aotearoa New Zealand and its health equity implications.

METHOD

We constructed a retrospective cohort including all pregnant women who delivered between 01 January 2013 and 31 December 2020 using administrative health datasets. Our outcomes were receipt of influenza or pertussis vaccine in any one of three relevant national databases (e.g. National Immunisation Register, Proclaims, or Pharmaceutical collection) during the eligible pregnancy.

RESULTS

Data from our retrospective cohort study show significant regional variation in maternal immunisation coverage for both influenza and pertussis from 2013 to 2020. Maximal coverage was around 50% in the best performing regions, which means that half of the women who were pregnant (183,737 women) were not protected. In addition, we found significant spatio-temporal variation and clustering of immunisation coverage. Our findings are interactively available to explore here: https://geohealthlab.shinyapps.io/hapumama/ CONCLUSION: Our study is one of the first to examine spatial variation in maternal vaccination coverage in pregnant women at a national level over space and time. This provides powerful tools to measure the impact of interventions to improve coverage at national and regional levels, with specific reference to inequities between ethnic groups, likely applicable to similar settings internationally.

Examining Public Messaging on Influenza Vaccine over Social Media: Unsupervised Deep Learning of 235,261 Twitter Posts from 2017 to 2023

Although influenza vaccines are safe and efficacious, vaccination rates have remained low globally. Today, with the advent of new media, many individuals turn to social media for personal health questions and information. However, misinformation may be rife, and health communications may be suboptimal. This study, therefore, aimed to investigate the public messaging related to influenza vaccines by organizations over Twitter, which may have a far-reaching influence. The theoretical framework of the COM-B (capacity, opportunity, and motivation component of behavior) model was used to interpret the findings to aid the design of messaging strategies. Employing search terms such as "flu jab", "flu vaccine", "influenza vaccine", and '" influenza jab", tweets posted in English and by organizations from 1 January 2017 to 1 March 2023 were extracted and analyzed. Using topic modeling, a total of 235,261 tweets by organizations over Twitter were grouped into four main topics: publicizing campaigns to encourage influenza vaccination, public education on the safety of influenza vaccine during pregnancy, public education on the appropriate age to receive influenza vaccine, and public education on the importance of influenza vaccine during pregnancy. Although there were no glaring pieces of misinformation or misconceptions, the current public messaging covered a rather limited scope. Further information could be provided about influenza and the benefits of vaccination (capability), promoting community, pharmacist-led influenza vaccination, and other avenues (opportunity), and providing greater incentivization and support for vaccination (motivation).

A national nudge study of differently framed messages to increase COVID-19 vaccine uptake in Saudi Arabia: A randomized controlled trial

Background

During the COVID-19 pandemic, Saudi Arabia witnessed hesitancy from a proportion of the population toward taking the vaccine; thus, it was necessary to nudge them to uptake it. This study was conducted to assess the impact of using different types of messages to nudge the public to increase the proportion of vaccinated individuals.

Methods

This study is a multi-arm randomized controlled trial aiming to assess the efficacy of using differently framed messages that appear as pop-notifications in Sehatty application. Of those who preregistered to receive a COVID-19 vaccine but didn't take it according to the Saudi national vaccine registry (n = 1,291,686), 12,000 individuals were randomly recruited and randomly assigned to one of five intervention groups (commitment, loss aversion, salience, social norms, and ego) or a control group. To ensure the exposure occurred in the intervention groups, we included only those who received the notification, which was confirmed by checking the information technology system. We used the Chi-square test to compare each intervention group against the control group separately. Also, we used the same test to investigate whether sex and age influenced the percentage of booked appointments in the intervention groups.

Results

Social norms, ego, salience and loss aversion groups had higher percentages of booked appointments when compared to the control group (21.0%, p = 0.001; 19.1%, p = 0.011; 19.0%, p = 0.013; 18.4%, p = 0.034, respectively). Moreover, when combining the intervention groups, the percentage was higher than the control group (p < 0.001). The percentages of booked appointments made by Young adults (18-35 years old) were higher than that of adults over 35 years old in the social norms (22.6%, p = 0.016) and ego groups (21.0%, p = 0.010). At the same time, sex didn't affect the percentages of booked appointments in any group.

Conclusion

Using different framings of messages to nudge the public to take vaccines can help increase the percentage of immunized individuals in a community. Nudges can boost the public health of a population during an unusual spread of vaccine-preventable diseases. Findings might also inspire governmental responses to other public health situations.

Care to share? Experimental evidence on code sharing behavior in the social sciences

Transparency and peer control are cornerstones of good scientific practice and entail the replication and reproduction of findings. The feasibility of replications, however, hinges on the premise that original researchers make their data and research code publicly available. This applies in particular to large-N observational studies, where analysis code is complex and may involve several ambiguous analytical decisions. To investigate which specific factors influence researchers' code sharing behavior upon request, we emailed code requests to 1,206 authors who published research articles based on data from the European Social Survey between 2015 and 2020. In this preregistered multifactorial field experiment, we randomly varied three aspects of our code request's wording in a 2x4x2 factorial design: the overall framing of our request (enhancement of social science research, response to replication crisis), the appeal why researchers should share their code (FAIR principles, academic altruism, prospect of citation, no information), and the perceived effort associated with code sharing (no code cleaning required, no information). Overall, 37.5% of successfully contacted authors supplied their analysis code. Of our experimental treatments, only framing affected researchers' code sharing behavior, though in the opposite direction we expected: Scientists who received the negative wording alluding to the replication crisis were more likely to share their research code. Taken together, our results highlight that the availability of research code will hardly be enhanced by small-scale individual interventions but instead requires large-scale institutional norms.

Dynamic Trends and Underlying Factors of COVID-19 Vaccine Booster Hesitancy in Adults: Cross-Sectional Observational Study

BACKGROUND

COVID-19 vaccine hesitancy reduces vaccination rates, which is detrimental to building herd immunity and halting the spread of COVID-19 and its variations. Most researches have simply identified the reasons affecting COVID-19 vaccination reluctance without delving into its dynamics, which makes forecasting future trends difficult.

OBJECTIVE

This study aimed to examine the current COVID-19 vaccine booster hesitancy rate in Chinese adults as well as the dynamics of vaccine hesitancy and its influencing factors. The results of this study will have practical implications for policy responses in mainland China, and effective COVID-19 booster vaccination in specific populations.

METHODS

The web-based survey was completed by creating questionnaires and using a stratified random sampling method to collect information from adults (≥18 years old) among 2556 households in 4 geographical regions of China. We collected sociodemographic information, health status, awareness of COVID-19 and its vaccine, self-perceptions, trust in medical staff and vaccine developers, and so on. The odds ratios and 95% CI for the statistical associations were estimated using logistic regression models.

RESULTS

Overall, 6659 participants (females: n=3540, 53.2%; males: n=3119, 46.8%) responded. In total, 533 (8%; 95% CI 7.4%-8.7%) participants presented a clear hesitancy in receiving the COVID-19 booster vaccination, while 736 (11.1%; 95% CI 10.3%-11.8%) expressed hesitancy in regular booster vaccination. A higher prevalence of vaccine hesitancy in both booster vaccination and regular booster vaccination was observed among participants with a history of allergies, experiencing chronic disease, lower levels of public health prevention measures or susceptibility or benefits or self-efficiency, higher levels of severity or barriers, and lower trust in both medical staff and vaccine developers (P<.05). The females and participants with higher education levels, higher levels of barriers, lower levels of susceptibility, and lower trust in vaccine developers preferred to have attitudinal changes from acceptance to hesitancy, while people with higher education levels, lower self-report health conditions, experiencing chronic disease, history of allergies, and lower trust in medical staff and developers were all positively associated with constant COVID-19 booster hesitancy.

CONCLUSIONS

The prevalence of COVID-19 vaccine booster hesitancy is not high in mainland China. However, there is a slight increment in hesitancy on regular booster vaccination. Conducting targeted information guidance for people with higher education levels and chronic diseases, as well as improving accessibility to booster vaccination and increasing trust in medical staff and vaccine producers may be highly effective in reducing vaccine hesitancy.

How Scientists View Vaccine Hesitancy

This paper examines possible causes, consequences, and potential solutions for addressing vaccine hesitancy in the United States, focusing on the perspectives of academic scientists. By examining the experiences of scientists, who are arguably a critical community in US society, we gain deeper insights into how they understand the complexities of vaccine hesitancy and whether their insights and opinions converge with or diverge from the current literature. We present findings from a national survey of a representative sample of academic scientists from the fields of biology and public health regarding vaccine hesitancy and related topics. Empirical analysis using descriptive, bivariate, and multivariate analyses covers multiple topics, including vaccine controversy, trust in science, causes of vaccine hesitancy, preferred policy and regulatory approaches, risk perceptions, and scientists' ethics and perceived communication roles. The results highlight a diversity of opinions within the scientific community regarding how to improve science-society communication in regard to vaccines, including the need to be transparent and candid to the public about the risk of vaccines and their research.

The persistence of cognitive biases in financial decisions across economic groups

While economic inequality continues to rise within countries, efforts to address it have been largely ineffective, particularly those involving behavioral approaches. It is often implied but not tested that choice patterns among low-income individuals may be a factor impeding behavioral interventions aimed at improving upward economic mobility. To test this, we assessed rates of ten cognitive biases across nearly 5000 participants from 27 countries. Our analyses were primarily focused on 1458 individuals that were either low-income adults or individuals who grew up in disadvantaged households but had above-average financial well-being as adults, known as positive deviants. Using discrete and complex models, we find evidence of no differences within or between groups or countries. We therefore conclude that choices impeded by cognitive biases alone cannot explain why some individuals do not experience upward economic mobility. Policies must combine both behavioral and structural interventions to improve financial well-being across populations.

How does nudging the COVID-19 vaccine play out in people who are in doubt about vaccination?

In spite of the growing availability of COVID-19 vaccines, a substantial number of people is reluctant or uncertain about getting the vaccine. Nudges may improve vaccine uptake but it is unclear how this plays out with the experience of autonomous choice, decision competence, decision satisfaction, and being pressured to make a choice. In an online experiment among a representative sample (N = 884), we examined whether a social norm nudge or a default nudge (either or not transparent) was effective in steering the desired choice of making a hypothetical early vaccination appointment as compared to making a later appointment or no appointment. We also examined how both nudges affected autonomy and related downstream consequences. None of the nudges proved effective in making the desired choice of early vaccination and neither did they impact on downstream consequences. Rather, our results indicate that participants who were certain about their choice (i.e., opted for the earliest available vaccination opportunity or not getting vaccinated at all) reported higher levels of autonomy, competence and satisfaction than participants who did not know yet about vaccination or who postponed the moment of getting their vaccination. We conclude that the experience of autonomy and related downstream consequences is determined by having made up one's mind about vaccination, and is not affected by attempts to nudge the individual.

Interventions for COVID-19 Vaccine Hesitancy: A Systematic Review and Narrative Synthesis

Vaccines effectively protect against COVID-19, but vaccine hesitancy and refusal hinder vaccination rates. This systematic review aimed to (1) review and describe current interventions for addressing COVID-19 vaccine hesitancy/refusal and (2) assess whether these interventions are effective for increasing vaccine uptake. The protocol was registered prospectively on PROSPERO and comprehensive search included Medline, Embase, CINAHL, PsycInfo, and Web of Science databases. Only studies that evaluated the effectiveness of non-financial interventions to address COVID-19 vaccine hesitancy were included, while those focusing intentions or financial incentive were excluded. Risk of bias for all included studies was evaluated using Cochrane risk of bias tools. In total, six articles were included in the review (total participants n = 200,720). A narrative synthesis was performed due to the absence of common quantitative metrics. Except for one randomized controlled trial, all studies reported that interventions were effective, increasing COVID-19 vaccination rates. However, non-randomized studies were subject to confounding biases. Evidence on the effectiveness of COVID-19 vaccine hesitancy interventions remains limited and further evidence is needed for the development of clear guidance on effective interventions to increase vaccine uptake.

Individual and Contextual Determinants of Flu Vaccination Adherence: A University Nudge Intervention

INTRODUCTION

The University of Salerno has implemented a nudge intervention with the aim of promoting vaccine adherence among employees of academia and identifying individual and contextual determinants that influence adherence.

METHOD

A purpose-built questionnaire was used during the reference period of October-December 2022 in order to assess levels of state anxiety (STAI-Y1), perceived stress (PSS-10), and public sentiments, which influence vaccination behavior, with consequences for the whole population (VCI).

RESULTS

Analysis of the results revealed a difference in mean scores on the PSS: those who have always adhered to the vaccination campaign compared to those who have never been vaccinated perceived higher levels of stress (12.01 vs. 11.33; F = 4.744, p = 0.031); furthermore, there was a relationship between the presence/absence of pathologies and VCI (F = 3,93; df = 1; p = 0.04).

CONCLUSIONS

The University of Salerno's nudge intervention made its employees more responsible for protecting the health of the academic community and encouraged good adherence to the flu vaccination campaign. University employees, equipped with high cultural tools, sought information primarily from institutional sources indicated by the university during the free vaccination campaign at the university's vaccine center.

Understanding the barriers and facilitators of vaccine hesitancy towards the COVID-19 vaccine in healthcare workers and healthcare students worldwide: An Umbrella Review

BACKGROUND

Healthcare workers (HCWs) and healthcare students display high levels of vaccine hesitancy with impact on healthcare provision, patient safety, and health promotion. The factors related to vaccine hesitancy have been reported in several systematic reviews. However, this evidence needs to be synthesised, as interventions to reduce vaccination hesitancy in this population are needed.

METHODS

This Umbrella Review aimed to explore the barriers and facilitators of vaccine hesitancy toward the COVID-19 vaccine for HCWs and healthcare students. The review was performed and reported in accordance with Joanna Briggs Institutes guidelines and the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. A protocol was preregistered on PROSPERO (CRD42022327354). Eight databases were searched from November 2019 to 23rd May 2022 to identify any systematic reviews that explored factors associated with hesitancy towards the COVID-19 vaccine for HCWs or healthcare students.

RESULTS

A total of 31 studies were included in the review. The majority of studies (71%) were appraised as strong or moderate quality and there was a slight degree of overlap (<5%) of primary studies between the reviews. Vaccine hesitancy was more common among HCWs and healthcare students in specific occupational roles (e.g. nurses) than others (e.g. physicians). Frequent reasons for hesitancy were related to sociodemographic factors (gender, age, ethnicity), occupational factors (COVID-19 exposure, perceived risk, mandatory vaccination), health factors (vaccination history), vaccine-related factors (concerns about safety, efficacy, side-effects, rapid development, testing, approval and distribution of the vaccine), social factors (social pressure, altruism and collective responsibility), distrust factors (key social actors, pandemic management), information factors (inadequate information and sources, exposure to misinformation).

CONCLUSION

The results from this Umbrella Review have wide-reaching implications for the research area, healthcare systems and institutions and governments worldwide. Designing tailored strategies for specific occupational groups is pivotal to increasing vaccine uptake and securing a safe healthcare provision worldwide.

COVID-19 Communication Campaigns for Vaccination: An Assessment with Perspectives for Future Equity-Centered Public Health Efforts

Although public and private institutions have spent billions of dollars on COVID-19 vaccination campaigns, many of which claim to be "equity-focused," few articles to date have objectively described the landscape of these campaigns or identified existing gaps with a focus on those populations disproportionately impacted by the virus. To these ends, a high-level landscape analysis of COVID-related communication campaigns was conducted. Analysis of 15 COVID-related communication campaigns based on six criteria (i.e., understandability, accessibility, actionability, credibility/trustworthiness, relevance/relatability, and timeliness) identified successful efforts, including campaigns aligned with the World Health Organization's Strategic Communications Framework and rooted in community co-design and communication science. The analysis also revealed five common shortcomings: campaigns were not end-user focused, only "checked the box" when communicating with historically under-resourced communities, were largely broadcast-focused and rarely involved two-way engagement strategies or tactics, demonstrated poor use of online communication approaches and failed to moderate campaign comment boards/social media sites, and commonly targeted "intermediary" audiences with materials that were not "end user ready." Based on these findings, the authors offer recommendations to guide funding and development of future health communication campaigns focused on reaching diverse audiences.

Clinician Communication to Address Vaccine Hesitancy

There are several factors that influence childhood vaccine uptake. Pediatric clinicians play a particularly influential role in parent vaccine decision-making. It is critical therefore that pediatric clinicians have a "communication toolbox"--a set of effective, evidence-based communication strategies to facilitate uptake of childhood vaccines--that they can use in conversations with parents about vaccines. In this article, recent advances in our understanding of what constitutes effective clinician vaccine communication with parents are discussed.

The burden of COVID-19 in French Guiana: Vaccine-averted deaths, hospitalizations and costs

Objectives

French Guiana, the least-vaccinated French territory, also has the lowest COVID-19 vaccination coverage in Latin America. We aimed to estimate how many deaths, hospitalizations and costs the vaccines had and could have avoided.

Methods

We calculated the Number Needed to Vaccinate to prevent one death per year, 1 standard hospitalization, 1 Intensive Care Unit admission given the mean incidence numbers of the past 6 months, and divided the number of persons vaccinated to estimate how many deaths and hospitalizations had been avoided in French Guiana at that time.

Results

The crude number needed to vaccinate to prevent one death per year, the crude number needed to vaccinate to prevent one hospitalization per 6 months were computed Based on our observed incidence and ICU admission rate, the crude number needed to vaccinate to prevent one ICU admission per 6 months.After 6 months with an incidence exceeding 400 per million inhabitants, and 148 observed deaths, we estimate that vaccination avoided 46 deaths (IC95%=43.5-48.7). If the number of vaccinated persons had reached the same proportion as mainland France, 141 deaths per year could have been prevented (IC95%=131.9-147.6).With 2085 hospitalization and 370 ICU admissions during the same period, we estimate that the current albeit low vaccination rate avoided 300 hospital (IC95%=280-313) and 77 (IC95%=72-81) ICU admissions. With the same vaccination rates as mainland France, we estimate that 900 hospitalizations and 231 ICU admissions would have been avoided.Similarly, there would have been 139 ICU admission (instead of 370).

Conclusions

In sparsely populated French Guiana these numbers are quite substantial and framing the vaccine benefits and wasted opportunities using such concrete numbers may help convincing undecided persons to get vaccinated.

Short Message Service Reminder Nudge for Parents and Influenza Vaccination Uptake in Children and Adolescents With Special Risk Medical Conditions: The Flutext-4U Randomized Clinical Trial

Importance

Children with chronic medical conditions are at increased risk of severe influenza. Uptake of influenza vaccination in children and adolescents with these identified special risk medical conditions (SRMCs) is suboptimal.

Objective

To assess the effectiveness of Flutext-4U, a parent short message service (SMS) reminder nudge intervention, in increasing influenza immunization in children and adolescents with SRMCs.

Design, Setting, and Participants

This randomized clinical trial was conducted at a tertiary pediatric hospital in Adelaide, South Australia, from April 15 to September 30, 2021. Children and adolescents aged 6 months to younger than 18 years with SRMCs and a subspecialist outpatient appointment over a 5-month period during the Australian seasonal influenza vaccination season (April-August 2021) were eligible to participate. Follow-up was until September 30, 2021.

Interventions

Participants were randomly assigned (1:1 ratio) to control: clinician nudges (hospital vaccine availability, ease of access, and recommendation from hospital subspecialists) or SMS intervention (control conditions plus an additional SMS reminder nudge to parents), with randomization stratified by age group (<5 years, 5-14 years, or >14 to <18 years).

Main Outcomes and Measures

The primary outcome was influenza vaccination, as confirmed by the Australian Immunisation Register.

Results

A total of 600 participants (intervention group: 298 [49.7%]; mean [SD] age, 11.5 [4.6] years; 162 female participants [54.4%]; control group: 302 [50.3%]; mean [SD] age, 11.4 [4.7] years; 155 female participants [51.3%]) were included. Influenza vaccination was 38.6% (113 of 293) in the SMS intervention group compared with 26.2% (79 of 302) in the control group (adjusted odds ratio [aOR], 1.79; 95% CI, 1.27-2.55; P = .001). Time to vaccine receipt was significantly lower among SMS participants (adjusted hazard ratio, 1.67; 95% CI, 1.25-2.22; P < .001). For participants randomly assigned by June 15, a significantly greater proportion receiving the SMS intervention were vaccinated during the optimal delivery period April to June 30 (SMS group: 40.0% [76 of 190] vs 25.4% [50 of 197]; aOR, 1.97; 95% CI, 1.28-3.06; P = .002).

Conclusions and Relevance

Results of this randomized clinical trial suggest that an additional SMS reminder nudge for parents delivered in the tertiary care hospital setting to children and adolescents with SMRCs resulted in higher influenza vaccine uptake compared with clinician nudges alone.

Trial Registration

ANZCTR Identifier: ACTRN12621000463875.

Examining an Altruism-Eliciting Video Intervention to Increase COVID-19 Vaccine Intentions in Younger Adults: A Qualitative Assessment Using the Realistic Evaluation Framework

COVID-19 vaccine-induced immunity wanes over time, and with the emergence of new variants, additional “booster” doses have been recommended in Canada. However, booster vaccination uptake has remained low, particularly amongst younger adults aged 18–39. A previous study by our research team found that an altruism-eliciting video increased COVID-19 vaccination intentions. Using qualitative methods, the present study aims to: (1) identify the factors that influence vaccine decision-making in Canadian younger adults; (2) understand younger adults’ perceptions of an altruism-eliciting video designed to increase COVID-19 vaccine intentions; and (3) explore how the video can be improved and adapted to the current pandemic context. We conducted three focus groups online with participants who: (1) received at least one booster vaccine, (2) received the primary series without any boosters, or (3) were unvaccinated. We used deductive and inductive approaches to analyze data. Deductively, informed by the realist evaluation framework, we synthesized data around three main themes: context, mechanism, and intervention-specific suggestions. Within each main theme, we deductively created subthemes based on the health belief model (HBM). For quotes that could not be captured by these subthemes, additional themes were created inductively. We found multiple factors that could be important considerations in future messaging to increase vaccine acceptance, such as feeling empowered, fostering confidence in government and institutions, providing diverse (such as both altruism and individualism) messaging, and including concrete data (such as the prevalence of vulnerable individuals). These findings suggest targeted messaging tailored to these themes would be helpful to increase COVID-19 booster vaccination amongst younger adults.

What motivates adults to accept influenza vaccine? An assessment of incentives, ease of access, messaging, and sources of information using a discrete choice experiment

Seasonal influenza vaccination rates remain low, and contribute to preventable influenza cases, hospitalizations, and deaths in the US. While numerous interventions have been implemented to increase vaccine uptake, there is a need to determine which interventions contribute most to vaccine willingness, particularly among age groups with vaccination rates that have plateaued at suboptimal levels. This study aimed to quantify the relative effect of multiple interventions on vaccine willingness to receive influenza vaccine in three age groups using a series of hypothetical situations with different behavioral interventions. We assessed the relative impact of four categories of interventions: source of vaccine messages, type of vaccination messages, vaccination incentives, and ease of vaccine access using a discrete choice experiment. Within each category, we investigated the role of four different attributes to measure their relative contribution to willingness to be vaccinated by removing one option from each of the intervention categories. Among the 1,763 Minnesota residents who volunteered for our study, participants expressed vaccine willingness in over 80% of the scenarios presented. Easy access to drop-in vaccination sites had the greatest impact on vaccine willingness in all age groups. Among the younger age group, small financial incentives also contributed to high vaccine willingness. Our results suggest that public health programs and vaccination campaigns may improve their chances of successfully increasing vaccine willingness if they offer interventions preferred by adults, including facilitating convenient access to vaccination and offering small monetary incentives, particularly for young adults.

The effects of default nudges on promoting approval of welfare cuts: An exploration during COVID-19

The global COVID-19 pandemic has created significant financial and operational challenges for some businesses. As a result, temporary welfare benefit reduction may be a tough but future-oriented choice for both employers and employees. The present study examined whether default nudges can be used to promote employees' approval of welfare-cutting policy while avoiding negative attitudes. Two online surveys were conducted during the first pandemic wave in China (February 2020). In the first study (N = 310), the participants were presented with a hypothetical welfare-cutting policy that used either an opt-in approach or an opt-out approach. We aimed to investigate how their approval and attitudes were different between two conditions. The results showed that the employees in the opt-out condition were more likely to accept the welfare-cutting policy than those in the opt-in condition, while participants' attitudes toward the policy employing opt-out approach were as negative as that employing opt-in approach. Study 2 (N = 1,519) involved a replication of Study 1 with two additional improved opt-out approaches (opt-out education and opt-out transparency). Compared with the opt-in approach and standard opt-out approach, the opt-out education approach both increased policy support and improved attitudes toward the welfare-cutting policy. The theoretical and practical implications of these findings are discussed.

A Bibliometric Analysis and Review of Nudge Research Using VOSviewer

With growing demands of decision making in the current era, the impact of the drivers behind individuals' preferences and institutional strategies becomes prominent. Coined in 2008, nudge is used to describe incentives for individuals' choices with foreseeable outcomes but without exclusion of alternative choices or reliance on financial stimuli. Consequently, nudge and its application in real-world situations led to a prosperous surge of studies in multiple disciplines. However, we are still facing a dearth of in-depth understanding of the status quo and future directions of research on nudge in a comprehensive fashion. To address the gap in knowledge, the present study adopted a bibliometric analysis of the existing literature related to the investigation and application of nudge by analyzing 1706 publications retrieved from Web of Science. The results indicated that (a) being a relatively newly developed theory, interest in nudge in academia has expanded both in volume and disciplines, with Western scholars and behavioral economists as the backbones; (b) future studies in nudge-related fields are expected to consolidate its current frontiers in individual behaviors while shedding light on new territories such as the digitalized environment. By incorporating state-of-the-art technologies to investigate extant research, the present study would be pivotal for the holistic understanding of the studies on nudge in recent years. Nevertheless, the inclusiveness and comprehensiveness of the review were limited by the size of the selected literature.

Quasi-experimental evaluation of a financial incentive for first-dose COVID-19 vaccination among adults aged ≥60 years in South Africa

INTRODUCTION

COVID-19 vaccination coverage in South Africa (RSA) remains low despite increased access to vaccines. On 1 November 2021, RSA introduced the Vooma Voucher programme which provided a small guaranteed financial incentive, a Vooma Voucher redeemable at grocery stores, for COVID-19 vaccination among older adults, a population most vulnerable to serious illness, hospitalisation and death. However, the association of financial incentives with vaccination coverage remains unclear.

METHODS

We evaluated the association of the conditional economic incentive programme with first-dose vaccination rates among adults (aged ≥60 years) through a quasi-experimental cohort study. The Vooma Voucher programme was a nationwide vaccination incentive programme implemented for adults aged ≥60 years from 1 November 2021 to 28 February 2022. We ran ITS models to evaluate the Vooma Voucher programme at national and provincial levels. We used data between 1 October 2021 and 27 November 2021 in models estimated at the daily level. Individuals who received their first vaccine dose received a text message to access a ZAR100 ($~7) voucher that was redeemable at grocery stores.

RESULTS

The Vooma Voucher programme was associated with a 7.15%-12.01% increase in daily first-dose vaccinations in November 2021 compared with late October 2021. Overall, the incentive accounted for 6476-10 874 additional first vaccine doses from 1 November to 27 November 2021, or 8.31%-13.95% of all doses administered to those aged ≥60 years during that period. This result is robust to the inclusion of controls for the number of active vaccine delivery sites and for the nationwide Vooma vaccination weekend initiative (12 November to 14 November), both of which also increased vaccinations through expanded access to vaccines and demand creation activities.

CONCLUSIONS

Financial incentives for COVID-19 vaccination led to a modest increase in first-dose vaccinations among older adults in RSA. Financial incentives and expanded access to vaccines may result in higher vaccination coverage.

TRIAL REGISTRATION NUMBER SANCTR

DOH-27-012022-9116.

Comparative effectiveness of mandates and financial policies targeting COVID-19 vaccine hesitancy: A randomized, controlled survey experiment

Experts debate whether COVID-19 vaccine mandates or financial incentives will reduce, rather than increase, interest in vaccination. Among 3,698 unvaccinated U.S. residents, we conducted a randomized, controlled survey-embedded experiment to estimate the absolute and relative psychological effects of vaccine policies specifying: mandates by employers or airlines, bars, and restaurants; lotteries for $1 million, $200,000, or $100,000; guaranteed cash for $1000, $200, or $100; and $1,000 as either a tax credit or penalty. Vaccine intention -the study outcome- predicts uptake and provides insight into the psychological mechanism that is most proximal to behavior (i.e., vaccination). Compared to controls, those who learned about the $1,000 cash reward policy were 17.1 (±5.3)% more likely to want vaccination. Employer mandates are more promising than other mandate policies (8.6 [+/- 7.4]% vs. 1.4 [+/- 6.0]%). The full results suggest that neither mandates nor financial incentives are likely to have counterproductive psychological effects. These policies are not mutually exclusive and, if implemented well, they may increase vaccine uptake.

Message testing in India for COVID-19 vaccine uptake: What appeal and what messenger are most persuasive?

Few studies have examined the relationships between the different aspects of vaccination communication and vaccine attitudes. We aimed to evaluate the influence of three unique messaging appeal framings of vaccination from two types of messengers on COVID-19 vaccine acceptance in India. We surveyed 534 online participants in India using Amazon Mechanical Turk (MTurk) from December 2021 through January 2022. We assessed participants' perception of three messaging appeals of vaccination - COVID-19 disease health outcomes, social norms related to vaccination, and economic impact of COVID-19 - from two messengers, healthcare providers (HCP) and peers. Using a multivariable multinomial logistic regression, we examined participants' ad preference and vaccine hesitancy. Participants expressed a high level of approval for all of the ads, with >80% positive responses for all questions across ads. Overall ads delivered by health care workers were preferred by a majority of participants in our study (n = 381, 71.4%). Ad preference ranged from 3.6% (n = 19) social norm/peer ad to 32.4% (n = 173) health outcome/HCP ad and half of participants preferred the health outcome ad (n = 279, 52.3%). Additionally, vaccine hesitancy was not related to preference (p = .513): HCP vs. peer ads (p = .522); message type (p = .284). The results suggest that all three appeals tested were generally acceptable, as well as the two messenger types, although preference was for the health care provider messenger and health outcome appeal. Individuals are motivated and influenced by a multitude of factors, requiring vaccine messaging that is persuasive, salient, and induces contextually relevant action.

An Examination of US COVID-19 Vaccine Distribution in New Jersey, Pennsylvania, and New York

COVID-19 quickly spread across the United States (US) while communications and policies at all government levels suffered from inconsistency, misinformation, and lack of coordination. In order to explain the discrepancy between availability and population uptake, a case study was conducted analyzing vaccine rollout plans, social media, and Health Officer/Other Key Informant interviews in New Jersey, New York, and Pennsylvania. Key research questions included, "What were the barriers and facilitators of early COVID vaccine distribution?" and "What mechanisms in the community emerged to alleviate strains in early vaccination?" Findings from this study revealed that pre-existing emergency preparedness infrastructures and plans developed since the 9/11 tragedy were seemingly abandoned. This caused health departments at all levels of government to make impromptu, non-uniform decisions leading to confusion, vaccine hesitancy, and ultimately low uptake. The results indicate that future vaccine rollout best practices must include evidence-based decision-making, coordinated communications, and outreach to high-priority and vulnerable communities.