Influence of Vaccination Characteristics on COVID-19 Vaccine Acceptance Among Working-Age People in Hong Kong, China: A Discrete Choice Experiment

The Evolving Landscape of Discrete Choice Experiments in Health Economics: A Systematic Review

INTRODUCTION

Stakeholder preference evaluations are increasingly emphasized in healthcare policy and health technology assessment. Discrete choice experiments (DCEs) are the most common method for quantifying preferences among patients, the public, and healthcare professionals. While prior reviews (1990-2017) have examined DCE trends, no comprehensive synthesis exists for studies published since 2018. This updated review (2018-2023) provides critical insights into evolving methodologies and global trends in health-related DCEs.

METHODS

A systematic search (2018-2023) of Medline, Embase, and Web of Science identified relevant studies. Studies were screened for inclusion and data were extracted, including details on DCE design and analysis. To enable trend comparisons, the search strategy and extraction items aligned with previous reviews.

RESULTS

Of 2663 identified papers, 1279 met the inclusion criteria, reflecting a significant rise in published DCEs over time. DCEs were conducted globally, with a remarkable increase in publications from Asia and Africa compared with previous reviews. Experimental designs and econometric models have advanced, continuing prior trends. Notably, most recent DCEs were administered online.

DISCUSSION

The rapid growth of DCE applications underscores their importance in health research. While the methodology is advancing rapidly, it is crucial that researchers provide full transparency in reporting their methods, particularly in detailing experimental designs and validity tests, which are too often overlooked. Key recommendations include improving reporting of experimental designs, applying validity tests, following good practices for presenting benefit-risk attributes, and adopting open science practices. Ensuring methodological rigor will maximize the impact and reproducibility of DCE research in health economics.

COVID-19 Vaccine Preferences in China: A Comparison of Discrete Choice Experiment and Profile Case Best-Worst Scaling

OBJECTIVES

Little is known about the diversity of residents' preferences for COVID-19 vaccines during the time when COVID-19 management was downgraded in China. This study aims to investigate these preferences using discrete choice experiment (DCE) and profile case best-worst scaling (BWS-2), and to assess the concordance between these two methods.

METHODS

Chinese residents recruited for the online survey were asked to evaluate COVID-19 vaccine profiles through both DCE and BWS-2 from April to July 2023. Attributes included effectiveness, duration of protection, risk of severe adverse events (degree), the total out-of-pocket (OOP) cost, brand, and the vaccination method. We utilized conditional regression and mixed logit regression models to estimate the preference levels for potential attributes. To assess preference concordance between the two methods, re-scaling and the Spearman correlation test were used. Additionally, subgroup analysis was conducted to determine the most suitable method for different population groups, categorized by vaccine hesitancy and risk level.

RESULTS

A total of 438 (71.22%) respondents were included. A similar pattern was found in the DCE and BWS-2 methods, with the respondents having a strong preference for 90% vaccine effectiveness. However, the methods diverged in other preferences; DCE favored domestic brands and low severe adverse event risk, while BWS-2 preferred moderate risk and three years of protection. Concordance assessment, including Spearman's correlation and linear regression, showed no significant correlation and poor concordance between the methods, underscoring these differences. Preference heterogeneity is revealed among different groups; however, effectiveness remained the most important attribute for all subgroups of the population. Oral vaccination was the preferred option for both the vaccine-hesitant and high-risk groups.

CONCLUSION

This study offers new insights into the varying preferences for COVID-19 vaccines among Chinese residents following the downgrading of pandemic management measures. The findings underscore the need for diverse strategies in vaccine policy design. Special emphasis should be placed on vaccine attributes that align with public priorities, such as high effectiveness and low risk levels, to enhance vaccine uptake.

Analyzing HPV Vaccination Service Preferences among Female University Students in China: A Discrete Choice Experiment

OBJECTIVE

Despite being primary beneficiaries of human papillomavirus (HPV) vaccines, female university students in China exhibit low vaccination rates. This study aimed to assess their preferences for HPV vaccination services and evaluate the relative importance of various factors to inform vaccination strategy development.

METHODS

Through a literature review and expert consultations, we identified five key attributes for study: effectiveness, protection duration, waiting time, distance, and out-of-pocket (OOP) payment. A D-efficient design was used to create a discrete choice experiment (DCE) questionnaire. We collected data via face-to-face interviews and online surveys from female students across seven universities in China, employing mixed logit and latent class logit models to analyze the data. The predicted uptake and compensating variation (CV) were used to compare different vaccination service scenarios.

RESULTS

From 1178 valid questionnaires, with an effective response rate of 92.9%, we found that effectiveness was the most significant factor influencing vaccination preference, followed by protection duration, OOP payment and waiting time, with less concern for distance. The preferred services included a 90% effective vaccine, lifetime protection, a waiting time of less than three months, a travel time of more than 60 min, and low OOP payment. Significant variability in preferences across different vaccination service scenarios was observed, affecting potential market shares. The CV analysis showed female students were willing to spend approximately CNY 5612.79 to include a hypothetical 'Service 5' (a vaccine with higher valency than the nine-valent HPV vaccine) in their prevention options.

CONCLUSIONS

The findings underscore the need for personalized, need-based HPV vaccination services that cater specifically to the preferences of female university students to increase vaccination uptake and protect their health.

Practices, Attitudes, and Knowledge Regarding Recombinant Zoster Vaccine Among Family Medicine Residents in Riyadh, Saudi Arabia

Background The aim of the research is to determine the existing knowledge, perceived practices, and attitudes toward the recombinant Zoster vaccine among family medicine residents (FMR) included in the medical profession. The present study aims to narrow down the identified gap in knowledge and develop vaccinations that will assist the targeted deme to eradicate zoster and the aftermaths that accompany it. Methods This research utilizes a descriptive cross-sectional survey design to assess the knowledge, practices, and attitudes of FMR toward the zoster vaccine in Riyadh, Saudi Arabia. By quantifying data at a specific point in time, this design allows for a detailed examination of the current status across various levels of residency programs. Participants from different institutions are interviewed simultaneously, enabling a thorough study of the targeted population group. The study includes 154 FMR from three different levels (R1, R2, R3) enrolled in residency programs at various institutions in Riyadh, Saudi Arabia. These participants were selected from a group of individuals invited to share their prior knowledge, habits, and beliefs regarding the recombinant Zoster vaccine. The study offers detailed statistical insights into demographics, vaccination attitudes, and knowledge among healthcare professionals. Key findings highlight diverse recommendations for different adult groups, the prevalence of vaccine availability, and the main sources of immunization information. Results The study found diverse recommendations for vaccination among different adult groups, with mean recommendations ranging from 2.50 to 2.94. Nearly all respondents (96.8%) reported having the vaccine available at their place of practice. However, knowledge gaps were evident, particularly concerning vaccination timing and specific requirements, highlighting the need for targeted education and clearer guidelines in vaccination practices among healthcare providers. Conclusion The study highlights the nuanced vaccination recommendations among healthcare professionals, particularly for different adult populations, and the availability of varicella-zoster virus (VZV) vaccines. The reliance on diverse information sources underscores the need for targeted educational efforts to ensure accurate and consistent immunization practices across healthcare settings. Addressing uncertainties and promoting informed decision-making can enhance vaccination uptake and patient care outcomes in clinical practice.

Preferences for COVID-19 Vaccines: Systematic Literature Review of Discrete Choice Experiments

BACKGROUND

Vaccination can be viewed as comprising the most important defensive barriers to protect susceptible groups from infection. However, vaccine hesitancy for COVID-19 is widespread worldwide.

OBJECTIVE

We aimed to systematically review studies eliciting the COVID-19 vaccine preference using discrete choice experiments.

METHODS

A literature search was conducted in PubMed, Embase, Web of Science, Scopus, and CINAHL Plus platforms in April 2023. Search terms included discrete choice experiments, COVID-19, and vaccines and related synonyms. Descriptive statistics were used to summarize the study characteristics. Subgroup analyses were performed by factors such as high-income countries and low- and middle-income countries and study period (before, during, and after the pandemic wave). Quality appraisal was performed using the 5-item Purpose, Respondents, Explanation, Findings, and Significance checklist.

RESULTS

The search yield a total of 623 records, and 47 studies with 53 data points were finally included. Attributes were grouped into 4 categories: outcome, process, cost, and others. The vaccine effectiveness (21/53, 40%) and safety (7/53, 13%) were the most frequently reported and important attributes. Subgroup analyses showed that vaccine effectiveness was the most important attribute, although the preference varied by subgroups. Compared to high-income countries (3/29, 10%), a higher proportion of low- and middle-income countries (4/24, 17%) prioritized safety. As the pandemic progressed, the duration of protection (2/24, 8%) during the pandemic wave and COVID-19 mortality risk (5/25, 20%) after the pandemic wave emerged as 2 of the most important attributes.

CONCLUSIONS

Our review revealed the critical role of vaccine effectiveness and safety in COVID-19 vaccine preference. However, it should be noticed that preference heterogeneity was observed across subpopulations and may change over time.

TRIAL REGISTRATION

PROSPERO CRD42023422720; https://tinyurl.com/2etf7ny7.

Employees' seeking preference towards influenza vaccination in organization: A discrete choice experiment in China

To clarify the preferences of employees seeking influenza vaccination, a discrete choice experiment aims to understand the essential factors that close the gap between intention and behavior. A total of 866 employees with vaccination willingness willing to participated in a discrete choice experiment (DCE) between October 31st and December 6th, 2022 in China including the following attributes: price, vaccination setting, appointment mode, and service time. The data was analyzed using mixed logit models. Employees from smaller enterprises were more likely to get vaccinated collectively. For employees willing to get the influenza vaccine, 95.08 % of their choice was dominated by price. Employees' behavior varied according to their socioeconomic characteristics. Only female employees strongly favored work-site-based vaccination. Price was the primary factor considered by employees for getting the influenza vaccine. DCE would help to develop influenza vaccination intervention targeted at different groups in future studies.

Influences of mpox disease perceptions, sources and contents of information exposure on mpox vaccine uptake among gay, bisexual, and other men who have sex with men in Hong Kong, China

BACKGROUND

Following the global mpox outbreak in 2022, multiple regions in Asia have been reporting ongoing mpox cases within high-risk groups, including gay, bisexual, and other men who have sex with men (GBMSM). An optimal level of vaccination rate is essential to prevent further mpox outbreaks. However, no existing studies have examined mpox vaccine uptake among GBMSM in East Asia.

METHODS

A cross-sectional survey was conducted among a sample of 531 GBMSM in Hong Kong, China, between March and October 2023. The study used multivariable logistic regression models to investigate the associations between mpox-related disease perceptions, exposures to sources and contents of mpox-related information, and mpox vaccine uptake.

RESULTS

The prevalence of mpox vaccine uptake among GBMSM in Hong Kong was 21.7%, with 7.7% completing one dose and 13.9% completing two doses. GBMSM who were younger or earning less monthly income were less likely to have been vaccinated. After adjusting for confounding variables, participants who perceived more negative impacts on their lives if they were to contract mpox, more severe symptoms, and a more coherent understanding of mpox were positively associated with mpox vaccine uptake. In addition, more frequent exposure to information through the following sources: TV, newspaper, radio and posters, government websites, news websites or apps, other people's social media, and communication over the phone or face-to-face was positively associated with mpox vaccine uptake. Finally, more frequent exposure to the following information contents: mpox statistics from other countries, the Hong Kong government's responses to mpox cases, negative information about patients with mpox, and information on prevention and treatment of mpox were positively associated with mpox vaccine uptake.

CONCLUSIONS

This study provides timely and evidence-based implications to address health communication and messaging needs in promoting mpox vaccination among GBMSM in Hong Kong, relevant to regions with similar sociocultural contexts.

Estimating COVID-19 vaccine acceptance in pregnant and lactating women: a cross-sectional study in Lebanon

BACKGROUND

The COVID-19 pandemic highlights vaccination's critical role in reducing morbidity and mortality, depending on public attitude. This study aims to identify the estimates of COVID-19 vaccine acceptance in pregnant and lactating women, as well as associated potential factors.

METHODS

A cross-sectional study was conducted between August and September 2021, through an online survey and with a paper survey distributed in gynecology and pediatric clinics. Pregnant and breastfeeding women aged 18 years and above were recruited. The attitude scale was created specifically for evaluating attitudes towards the COVID-19 vaccine.

RESULTS

In total, 207 women participated, with 132 breastfeeding, 74 pregnant and 1 experiencing both conditions. Of these, one hundred and twenty women (58%) considered themselves at risk for COVID-19 infection. In addition, 51.7% (n = 107) of women expressed the intent to receive the vaccine once available. A multivariable linear regression was conducted taking the COVID-19 vaccination attitude scale as a dependent variable. The results revealed an R-squared value of 0.558, indicating that approximately 55.8% of the variance in the attitude scale was accounted for by the included predictors. The results showed that preventive measures (ß=2.25, 95% Confidence Interval (CI) [1.02; 3.48], p < 0.001), preference for vaccines made in Europe and America (ß=1.23; 95% CI [0.69-1.77], p < 0.001), protect yourself for getting sick (ß=4.22, 95% Confidence Interval (CI) [2.83; 5.61], p < 0.001) and belief in the importance of vaccination for themselves and their baby (ß=3.49; 95% CI [2.01; 4.98], p < 0.001) were associated with a positive attitude towards vaccination. Conversely, experiencing a previous bad reaction to a vaccine (ß= -1.35; 95% CI [0.85-1.85], p < 0.001) and concerns regarding COVID-19 vaccine safety (ß= -4.09; 95% CI [-5.98; -2.21], p < 0.001) were associated with a negative attitude towards vaccination.

CONCLUSION

Our findings reveal that COVID-19 vaccine acceptability among pregnant and breastfeeding women, amidst the pandemic was insufficient to meet community immunity. The identified reasons for vaccine reluctance, notably concerns about safety for both personal health and the health of their pregnancy or newborns, along with insufficient information about the vaccine, underscore the pressing need to address these factors to improve immunization rates.

Vaccine decision making in New Zealand: a discrete choice experiment

BACKGROUND

Vaccine hesitancy is a significant threat to global health. A key part of addressing hesitancy is to ensure that public health messaging prioritises information that is considered important to the public. This study aimed to examine how different vaccine characteristics affect public preferences for vaccines in New Zealand, what trade-offs they are willing to make between different vaccine characteristics, and how their preferences are affected by their vaccine-related conspiracy beliefs and COVID-19 vaccination status.

METHODS

An online discrete choice experiment (DCE) was designed to elicit individual preferences about vaccines using the 1000minds platform. Members of the general population of New Zealand aged ≥ 18 years were invited to complete the DCE. Participants were asked to indicate their preference between two options showing different combinations of vaccine characteristics. Data on sociodemographic characteristics were collected. Beliefs were measured using the vaccine conspiracy beliefs scale (VCBS) with scores ≥ 19 indicating strong vaccine-related conspiracy beliefs. The DCE was analysed using the PAPRIKA method (Potentially All Pairwise RanKings of all possible Alternatives) and preferences compared between respondents with high versus low VCBS scores and vaccinated versus unvaccinated respondents for COVID-19.

RESULTS

A total of 611 respondents from 15 regions completed the DCE. Mean (SD) age was 45.9 (14.7) years with most having had 2 or more doses of the coronavirus vaccine (86%). Mean (SD) VCBS score was 18.5 (12.4) indicating moderate vaccine-related conspiracy beliefs. Risk of severe adverse effects was the most highly valued vaccine characteristic, followed by vaccine effectiveness and duration of protection. Vaccine origin and route of administration were ranked least important. Respondents scoring high on the VCBS placed less value on the effectiveness of vaccines but greater value on development time and total number of doses (p < 0.001). COVID-19 unvaccinated respondents ranked development time and total number of doses more highly than those vaccinated respondents (p < 0.001).

CONCLUSIONS

Risk of severe adverse effects, vaccine effectiveness and duration of protection were rated by the New Zealand public as the top three most important vaccine characteristics. This information is important for informing public health messaging to promote vaccine uptake and inform vaccine decision-making.

Which factors drive the choice of the French-speaking Quebec population towards a COVID-19 vaccination programme: A discrete-choice experiment

OBJECTIVES

The aims of this study were to elicit preferences about the coronavirus disease 2019 (COVID-19) vaccine campaign in the general French-speaking adult Quebec population and to highlight the characteristics of the vaccine campaign that were of major importance.

METHODS

A discrete-choice experiment (DCE) was conducted between April and June 2021, in Quebec, Canada. A quota sampling method by age, gender and educational level was used to achieve a representative sample of the French-speaking adult population. The choice-based exercise was described by seven attributes within a vaccine campaign scenario. A mixed logit (MXL) model and a latent class logit (LCL) model were used to derive utility values. Age, gender, educational level, income and fear of COVID-19 were included as independent variables in the LCL.

RESULTS

A total of 1883 respondents were included for analysis, yielding 22,586 choices. From these choices, 3425 (15.16%) were refusals. In addition, 1159 (61.55%) individuals always accepted any of the vaccination campaigns, while 92 individuals (4.89%) always refused vaccine alternatives. According to the MXL, relative weight importance of attributes was effectiveness (32.50%), risk of side effects (24.76%), level of scientific evidence (22.51%), number of shots (15.73%), priority population (3.60%), type of vaccine (0.61%), and vaccination location (0.28%). Four classes were derived from the LCL model and attributes were more or less important according to them. Class 1 (19.8%) was more concerned about the effectiveness (27.99%), safety (24.22%) and the number of shots (21.82%), class 2 (55.3%) wanted a highly effective vaccine (40.16%) and class 3 (17.6%) gave high value to the scientific evidence (42.00%). Class 4 preferences (7.4%) were more balanced, with each attribute having a relative weight ranging from 1.84% (type of vaccine) to 21.32% (risk of side effects). Membership posterior probabilities to latent classes were found to be predicted by individual factors such as gender, annual income or fear of COVID-19.

CONCLUSIONS

Vaccination acceptance relies on multiple factors. This study allowed assessment of vaccination-specific issues through a choice-based exercise and description of factors influencing this choice by segmenting the sample and drawing profiles of individuals. Moreover, besides effectiveness and safety, a major point of this study was to show the importance given by the general population to the level of scientific evidence surrounding vaccines.

PATIENT OR PUBLIC CONTRIBUTION

A small group of citizens was involved in the conception, design and interpretation of data. Participants of the DCE were all from the general population.

COVID-19 vaccine hesitancy worldwide and its associated factors: a systematic review and meta-analysis

Introduction

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has taken a toll on humans, and the development of effective vaccines has been a promising tool to end the pandemic. However, for a vaccination program to be successful, a considerable proportion of the community must be vaccinated. Hence, public acceptance of coronavirus disease 2019 (COVID-19) vaccines has become the key to controlling the pandemic. Recent studies have shown vaccine hesitancy increasing over time. This systematic review aims to evaluate the COVID-19 vaccine hesitancy rate and related factors in different communities.

Method

A comprehensive search was performed in MEDLINE (via PubMed), Scopus, and Web of Science from January 1, 2019 to January 31, 2022. All relevant descriptive and observational studies (cross-sectional and longitudinal) on vaccine hesitancy and acceptance were included in this systematic review. In the meta-analysis, odds ratio (OR) was used to assess the effects of population characteristics on vaccine hesitancy, and event rate (acceptance rate) was the effect measure for overall acceptance. Publication bias was assessed using the funnel plot, Egger's test, and trim-and-fill methods.

Result

A total of 135 out of 6,417 studies were included after screening. A meta-analysis of 114 studies, including 849,911 participants, showed an overall acceptance rate of 63.1%. In addition, men, married individuals, educated people, those with a history of flu vaccination, those with higher income levels, those with comorbidities, and people living in urban areas were less hesitant.

Conclusion

Increasing public awareness of the importance of COVID-19 vaccines in overcoming the pandemic is crucial. Being men, living in an urban region, being married or educated, having a history of influenza vaccination, having a higher level of income status, and having a history of comorbidities are associated with higher COVID-19 vaccine acceptance.

Evaluating Knowledge, Attitudes, and Behaviors toward HPV Infection and Vaccination among University Students in Italy

BACKGROUND

This survey investigated the knowledge, attitudes, and behaviors towards HPV preventive measures among university students in Italy and their associated factors.

METHODS

The cross-sectional survey was conducted between November 2022 and April 2023.

RESULTS

Only 41.7% knew about HPV infection and the main preventive measures. Multilevel mixed-effects logistic regression analysis showed that females, those aged 25-30 years, those who have had oral sex, those who had received information about HPV infection and preventive measures from physicians, and those who needed additional information about HPV infection and preventive measures were more knowledgeable. Only 39.1% have received at least one HPV vaccination dose, whereas 29.2% and 31.7% had not been vaccinated or did not remember. Multilevel mixed-effects logistic regression analysis identified that female students enrolled in the field of health sciences, those who did not report a prior history of a sexually transmitted infection, and those with a higher knowledge about HPV infection and preventive measures were more willing to receive the HPV vaccination.

CONCLUSIONS

Despite some limitations, this was the first detailed survey on this topic conducted in the post-acute phase of COVID-19 among university students in Italy. The survey underlined the need to develop and to implement comprehensive educational programs and health interventions among students, to enhance their knowledge and modify their attitudes and improve the HPV vaccine uptake.

Knowledge, attitudes, and practices associated with frequent influenza vaccination among healthcare personnel in Peru, 2016─2018

Introduction

Despite a government-subsidized vaccination program, healthcare personnel (HCP) influenza vaccination uptake remains low in Peru. Using three years of cross-sectional surveys and an additional five years of prior vaccination history of HCP in Peru, we explored HCP knowledge, attitudes, and practices (KAP) of influenza illness and its impact on vaccination frequency.

Methods

In 2016, the Estudio Vacuna de Influenza Peru (VIP) cohort was initiated in Lima, Peru, which collected information about HCP KAP and influenza vaccination history from 2011─2018. HCP were classified by their 8-year influenza vaccination history as never (0 years), infrequently (1─4 years), or frequently (5─8 years) vaccinated. Logistic regression models were used to describe KAP associated with frequent compared to infrequent influenza vaccination, adjusted for each HCP's healthcare workplace, age, sex, preexisting medical conditions, occupation, and length of time providing direct patient care.

Results

From 2016─2018, 5131 HCP were recruited and 3120 fully enrolled in VIP; 2782 consistently reported influenza vaccination status and became our analytic sample. From 2011─2018, 14.3% of HCP never, 61.4% infrequently, and 24.4% frequently received influenza vaccines. Compared to HCP who were infrequently vaccinated, frequently vaccinated HCP were more likely to believe they were susceptible to influenza (adjusted odds ratio [aOR]:1.49, 95% confidence interval [CI]:1.22─1.82), perceived vaccination to be effective (aOR:1.92, 95%CI:1.59─2.32), were knowledgeable about influenza and vaccination (aOR:1.37, 95%CI:1.06─1.77), and believed vaccination had emotional benefits like reduced regret or anger if they became ill with influenza (aOR:1.96, 95%CI:1.60─2.42). HCP who reported vaccination barriers like not having time or a convenient place to receive vaccines had reduced odds of frequent vaccination (aOR:0.74, 95%CI:0.61─0.89) compared to those without reported barriers.

Conclusion

Few HCP frequently received influenza vaccines during an eight-year period. To increase HCP influenza vaccination in middle-income settings like Peru, campaigns could strengthen influenza risk perception, vaccine knowledge, and accessibility.

Levels and Determinants of COVID-19 Vaccination at a Later Phase among Chinese Older People Aged 60 Years or Older: A Population-Based Survey

The early attainment of high COVID-19 vaccination rates can minimize avoidable hospitalizations/deaths. The fifth wave COVID-19 outbreak in Hong Kong caused >9000 deaths, and most of them were unvaccinated older people. This study hence investigated determinants of taking the first dose vaccination at a later phase (Phase 3: during the fifth wave outbreak, i.e., February-July 2022) versus two earlier phases (Phase 1: first six months since vaccine rollout, i.e., February-July 2021; Phase 2: six months prior to the outbreak, i.e., August 2021-January 2022) via a random telephone survey among 386 ever-vaccinated Hong Kong older people aged ≥60 (June/July 2022). A total of 27.7%, 51.1%, and 21.3% took the first dose at Phase 1, Phase 2, and Phase 3, respectively. Unfavorable perceptions related to COVID-19/vaccination, exposure to conflicting/counter-information about the suitability of older people's vaccination from various sources, unsupportive family influences prior to the outbreak, and depressive symptoms were significantly associated with taking the first dose at Phase 3 instead of Phase 1 and Phase 2. To speed up COVID-19 vaccination and avoid unnecessary deaths, the government and health professionals should rectify misinformation, provide clear/consistent information for older people and their family members, and focus on those having depressive symptoms at an earlier stage of the pandemic.

Loss-framing of information and pre-vaccination consultation improve COVID-19 vaccine acceptance: A survey experiment

Backgrounds

Vaccination remains one of the most effective ways to protect populations from COVID-19 infection, severe conditions, and death. This study aims to examine whether the gain/loss-framing of information, provision of subsidized pre-vaccination physician consultation, and cash incentives can improve COVID-19 acceptance amongst adults.

Methods

A survey experiment was conducted within a broader cross-sectional survey of people aged 18-64 years in Hong Kong, China. The participants were randomly assigned to one of the eight groups derived from full-factorial design of the three strategies with stratification by age and sex. The vaccine acceptance rate was compared between people with and without any of the strategies. The heterogeneous effects of these strategies were identified for those with different perceptions of the pandemics and vaccine in multiple logistic regressions.

Results

The survey experiment collected 1,000 valid responses. It found that loss-framed information and provision of subsidized physician consultation to assess suitability to be vaccinated, can improve vaccine acceptance, while cash incentives did not make a difference. The improvement effect of loss-framing information and physician consultation is stronger among those with higher perceived infection risk and severity of condition, as well as unvaccinated people with lower confidence in vaccine safety.

Conclusions

The findings indicated that individualized loss-framing messages and equitable provision of subsidized pre-vaccination physician consultations can be incorporated in efforts to promote vaccine acceptance and vaccination roll-out speed. However, it remains inconclusive whether and how universal cash incentives may be deployed to support vaccination promotion.

COVID-19 Vaccination among a Population Experiencing Homelessness: A Survey in Italy

The purposes of this cross-sectional study were to determine the knowledge, attitudes, and behaviors about COVID-19 and its vaccination among 313 individuals experiencing homelessness in Italy and to identify the associated factors. A total of 20.5% identified the virus as a causative agent for COVID-19 and 44.2% identified how the SARS-CoV-2 infection wastransmitted. Those living in homeless shelters were more likely to have this knowledge. Concerns about the safety of the COVID-19 vaccine werehigher in those who were younger, with secondary school as the highest level of education, who practiced Christianity, and who did not believe that COVID-19 was a severe disease. A total of 83.9% received the vaccination. Those who were older, who had correct knowledge, whoperceived to be at a higher risk of getting the disease, and who had a lower concern about the vaccine side effects were more likely to have received the vaccination. The primary reasons for accepting the COVID-19 vaccine were that it wasa preventive measure and that it wasmandatory; those unvaccinated indicated, as the main reasons, a fear of side effects and that it wasnot useful. A relationship and communication between healthcare professionals and this hard-to-reach population are needed, with the implementation of educational and information programs.

The association between social media use and hesitancy toward COVID-19 vaccine booster shots in China: A web-based cross-sectional survey

COVID-19 vaccine booster shots are necessary to provide durable immunity and stronger protection against the emerging SARS-CoV-2 variants. As a major platform for access to information, social media plays an important role in disseminating health information. This study aimed to evaluate hesitancy toward COVID-19 vaccine booster shots in China, assess its association with social media use, and provide information to manage social media. We conducted a cross-sectional study across all 31 provinces in mainland China from November 12, 2021, to November 17, 2021. In total, 3,119 of 3,242 participants completed the questionnaire (response rate = 96.2%). COVID-19 vaccine booster shot hesitancy rate in China was 6.5% (95% CI: 5.6-7.3). Unemployment (adjusted odds ratio [aOR] 2.428, 95% CI: 1.590-3.670), low monthly income (aOR 2.854,95% CI: 1.561-5.281), low scores of knowledge (aOR 0.917, 95% CI: 0.869-0.968) and low level of cues to action (aOR 0.773, 95% CI: 0.689-0.869) were associated with vaccine hesitancy. Compared with public social media, lower vaccine hesitancy was associated with high perceived importance of social media (aOR 0.252, 95% CI: 0.146-0.445) and official social media use (aOR 0.671, 95% CI: 0.467-0.954), while higher vaccine hesitancy was associated with traditional media use (aOR 3.718, 95% CI: 1.282-10.273). More efforts are needed to regulate the content of social media and filtering out misinformation. The role of official social media in disseminating health information should be enhanced.

Parental preference for Haemophilus influenzae type b vaccination in Zhejiang Province, China: A discrete choice experiment

Background

China is the only country in the world that has not included the Haemophilus influenzae type b (Hib) vaccine in its National Immunization Program, making it more difficult to eliminate Hib-related diseases through Hib vaccination. It is necessary to study parental preferences for Hib vaccination to optimize vaccine promotion strategies in China.

Objective

This study aimed to investigate Chinese parental preference for five attributes of Hib vaccination, i.e., the place of origin, effectiveness, adverse event, doctors' recommendation, and the price of full vaccination when making a decision to vaccinate their children under 2 years old.

Methods

A cross-sectional survey was conducted in two cities in Zhejiang Province from November to December in 2020 using a discrete choice experiment (DCE). A mixed logit model was used to estimate participating parents' preference for Hib vaccination attributes included in the DCE. Subgroup analysis and probability analysis were also conducted to capture the heterogeneity and trade-off of parental preference for Hib vaccination.

Results

Data from 6,168 observations were included in the analyses. Parents of children are, on average, more likely to voice a positive preference for Hib vaccination. Such attributes of Hib vaccination as effectiveness and doctor's recommendation have a significant positive influence on parents' preference for Hib vaccination, while imported vaccines, adverse events, and the price of full vaccination have a significant negative influence on parents' preference. Parents with different demographic characteristics also existed heterogeneities in preference for Hib vaccination. Parents will make a trade-off on price if the Hib vaccine has a good performance on effectiveness and safety.

Conclusion

The study found that, regardless of the place of origin of the Hib vaccine, parents with children under 2 years old prefer to compromise on price if the vaccine has a better effectiveness and safety profile. A proactive recommendation from doctors would strengthen their willingness for Hib vaccination. These findings help aid the development of communication strategies with parents for Hib vaccination in China.

The Willingness to get Vaccinated Against SARS-CoV-2 Virus among Southeast Asian Countries: Does the Vaccine Brand Matter?

The current study uses data surveyed with 2,500 respondents during August and September 2021 in Vietnam, Indonesia, the Philippines and Malaysia to examine the willingness to get vaccinated against SARS-CoV-2 virus with six COVID-19 vaccines. The willingness to get vaccinated varies according to the vaccine brands and selected influential factors. Particularly, the percentage of respondents who are willing to get vaccinated with Pfizer, Moderna and AstraZeneca dominates that of those who are willing to get vaccinated with Sinopharm, Janssen and Sputnik V vaccines. Results generated from the binary logistic regressions show that the impact of the selected influential factors on the willingness to get vaccinated varies in terms of magnitude and direction, and depending on the vaccine brands. The results indicate that additional scientific evidence on the efficacy and safety of the vaccines is essential for the respondents to decide whether to vaccinate or not. Such evidence can be made available in multiple formats and provided through appropriate channels and vaccination communication campaigns.

A Systematic Investigation of American Vaccination Preference via Historical Data

While COVID-19 vaccines are generally available, not all people receive vaccines. To reach herd immunity, most of a population must be vaccinated. It is, thus, important to identify factors influencing people’s vaccination preferences, as knowledge of these preferences allows for governments and health programs to increase their vaccine coverage more effectively. Fortunately, vaccination data were collected by U.S. Census Bureau in partnership with the CDC via the Household Pulse Survey (HPS) for Americans. This study presents the first analysis of the 24 vaccination datasets collected by the HPS from January 2021 to May 2022 for 250 million respondents of different ages, genders, sexual orientations, races, education statuses, marital statuses, household sizes, household income levels, and resources used for spending needs, and with different reasons for not receiving or planning to receive a vaccine. Statistical analysis techniques, including an analysis of variance (ANOVA), Tukey multiple comparisons test, and hierarchical clustering (HC), were implemented to analyze the HPS vaccination data in the R language. It was found that sexual orientation, gender, age, and education had statistically significant influences on the vaccination rates. In particular, the gay/lesbian group showed a higher vaccination rate than the straight group; the transgender group had a lower vaccination rate than either the female or the male groups; older respondents showed greater preference for vaccination; respondents with higher education levels also preferred vaccination. As for the other factors that were not significant enough to influence vaccinations in the ANOVA, notable trends were found. Asian Americans had higher vaccination rates than other races; respondents from larger household sizes had a lower chance of getting vaccinated; the unmarried group showed the lowed vaccination rate in the marital category; the respondents depending on borrowed money from the Supplemental Nutrition Assistance Program (SNAP) showed a lower vaccination rate than people with regular incomes. Concerns regarding the side-effects and the safety of the vaccines were the two major reasons for vaccination hesitance at the beginning of the pandemic, while having no trust in the vaccines and no trust in the government became more common in the later stage of the pandemic. The findings in this study can be used by governments or organizations to improve their vaccination campaigns or methods of combating future pandemics.

Vaccine Resistance and Hesitancy among Older Adults Who Live Alone or Only with an Older Partner in Community in the Early Stage of the Fifth Wave of COVID-19 in Hong Kong

Vaccination is an effective way in providing protection against COVID-19 infection and severe outcomes. However, vaccine resistance and hesitancy are a great concern among vulnerable populations including older adults who live alone or only with an older partner. This study examined their vaccination status and reasons and associated factors of vaccine resistance and hesitancy. A cross-sectional study was conducted among older adults living alone or only with an older partner in communities in Hong Kong. Participants were interviewed between October 2021 and February 2022. Logistic regression analyses were employed to examine factors associated with vaccine resistance and hesitancy. Of the 2109 included participants, the mean age was 79.3 years (SD 7.6), 1460 (69.2%) were female, 1334 (63.3%) lived alone, and 1621 (76.9%) were receiving social security support. The vaccine uptake, non-uptake (i.e., resistance), and hesitancy rates were 50.1%, 34.4%, and 15.5%, respectively. The top four reasons for vaccine resistance and hesitancy were “Not feeling in good health” (27%), “Worry about vaccine side effects” (18%), “Feeling no need” (10%), and “Lack of recommendation from doctors” (9%). Vaccine resistance and hesitancy was significantly associated with older age, living alone, more chronic conditions, fewer types of social media use, and lower self-rated health status. Similar associations can be observed in their separate analysis for vaccine resistance and vaccine hesitancy, and ever hospital admission over the past 6 months was additionally related to vaccine hesitancy. Older people who live alone or only with an older partner had a low vaccination rate. Poor health or worry about vaccine side effects were the most common reasons for their vaccine resistance and hesitancy. Actions are greatly needed to improve the uptake rate among this vulnerable population, especially those who were older, have poorer health, and use less social media.

Social media and attitudes towards a COVID-19 vaccination: A systematic review of the literature

Background

Vaccine hesitancy continues to limit global efforts in combatting the COVID-19 pandemic. Emerging research demonstrates the role of social media in disseminating information and potentially influencing people's attitudes towards public health campaigns. This systematic review sought to synthesize the current evidence regarding the potential role of social media in shaping COVID-19 vaccination attitudes, and to explore its potential for shaping public health interventions to address the issue of vaccine hesitancy.

Methods

We performed a systematic review of the studies published from inception to 13 of March2022 by searching PubMed, Web of Science, Embase, PsychNET, Scopus, CINAHL, and MEDLINE. Studies that reported outcomes related to coronavirus disease 2019 (COVID-19) vaccine (attitudes, opinion, etc.) gathered from the social media platforms, and those analyzing the relationship between social media use and COVID-19 hesitancy/acceptance were included. Studies that reported no outcome of interest or analyzed data from sources other than social media (websites, newspapers, etc.) will be excluded. The Newcastle Ottawa Scale (NOS) was used to assess the quality of all cross-sectional studies included in this review. This study is registered with PROSPERO (CRD42021283219).

Findings

Of the 2539 records identified, a total of 156 articles fully met the inclusion criteria. Overall, the quality of the cross-sectional studies was moderate - 2 studies received 10 stars, 5 studies received 9 stars, 9 studies were evaluated with 8, 12 studies with 7,16 studies with 6, 11 studies with 5, and 6 studies with 4 stars. The included studies were categorized into four categories. Cross-sectional studies reporting the association between reliance on social media and vaccine intentions mainly observed a negative relationship. Studies that performed thematic analyses of extracted social media data, mainly observed a domination of vaccine hesitant topics. Studies that explored the degree of polarization of specific social media contents related to COVID-19 vaccines observed a similar degree of content for both positive and negative tone posted on different social media platforms. Finally, studies that explored the fluctuations of vaccination attitudes/opinions gathered from social media identified specific events as significant cofactors that affect and shape vaccination intentions of individuals.

Interpretation

This thorough examination of the various roles social media can play in disseminating information to the public, as well as how individuals behave on social media in the context of public health events, articulates the potential of social media as a platform of public health intervention to address vaccine hesitancy.

Funding

None.

COVID-19 Vaccination Preferences of University Students and Staff in Hong Kong

Importance

COVID-19 has required universities to rapidly develop vaccination policies for students and staff, yet little is known about the preferences of these individuals toward vaccination.

Objective

To quantify student and staff preferences for COVID-19 vaccination at a university in Hong Kong.

Design, Setting, and Participants

A cross-sectional online survey study was conducted from July 20 to September 21, 2021, before the announcement of a campus-wide vaccine mandate. A survey of 42 451 eligible university students and staff used discrete-choice experiment methods to quantify 7 attributes of COVID-19 vaccination: risk of a mild or moderate adverse event after vaccination, risk of a severe adverse event after vaccination, efficacy against COVID-19 infection, efficacy against severe manifestation of COVID-19 infection, duration of protection after vaccination, incentive for completing vaccination, and out-of-pocket costs.

Main Outcomes and Measures

A mixed logit regression model was used to estimate the preferences of attributes for COVID-19 vaccines and marginal willingness to pay (mWTP) adjusted for background characteristics, role, vaccination, and COVID-19 infection status of family or friends, adverse event status after vaccination among family and friends of participants, and scenario block.

Results

Among 42 451 eligible university students and staff invited, 3423 individuals completed the survey (mean [SD] age, 27.1 [9.9] years; 2053 [60.0%] women). Participants included 2506 students (73.2%) and 917 staff (26.8%), with a response rate of 8.1%. Quarantine-free travel was preferred (β = 0.86; 95% CI, 0.72-0.99; mWTP: $235.9; 95% CI, $190.3-$294.2), followed by efficacy against any COVID-19 infection (β = 0.30; 95% CI, 0.29-0.32; mWTP: $84.1; 95% CI, $71.8-$100.8), against severe manifestation of COVID-19 infection (β = 0.25; 95% CI, 0.24-0.27; mWTP: $69.7; 95% CI, $465-$653), and risk of severe adverse events following vaccination (β = -0.24; 95% CI, -0.27 to -0.21; mWTP: -$66.8; 95% CI, -$81.5 to -$55.3). Participants were less concerned about protection duration (β = 0.17; 95% CI, 0.15-0.18; mWTP: $46.0; 95% CI, $38.6-$56.2) and risk of mild to moderate adverse events (β = -0.12; 95% CI, -0.13 to -0.10; mWTP: -$32.7; 95% CI, -$41.2 to -$26.4).

Conclusions and Relevance

Preference of all attributes were significant and were considered important by the participants for vaccine decision-making. Insights drawn could assist policy makers in future vaccination decisions, such as campus vaccine mandate and requirement of a third dose.

Impact of information framing and vaccination characteristics on parental COVID-19 vaccine acceptance for children: a discrete choice experiment

This study aimed to test the influence of vaccination characteristics and gain/loss-framing of information, on parental acceptance of the coronavirus disease 2019 (COVID-19) vaccination for their minor children. A discrete choice experiment was conducted among parents of children aged 0-17 years from September to October 2021 in Hong Kong. Respondents were randomly assigned to four groups with different framing of information and asked to choose hypothetical vaccination alternatives, described by seven attributes that were derived from prior qualitative interviews. A mixed logit model was adopted to analyze the effect of attributes and information framing on parental vaccination acceptance. The vaccine acceptance rates under different scenarios were also estimated. A total of 298 valid responses were obtained. It was found that the BioNTech brand, higher efficacy, less serious adverse events and more vaccination coverage in children significantly improved parental acceptance. Additionally, loss-framing increased parental acceptance compared with gain-framing, while the presentation of mortality information did not make a difference. Acceptance was also associated with parental uptake of the COVID-19 vaccine and the children's age.

CONCLUSION

The findings imply that factors including gain/loss information framing, importance of vaccine characteristics, and peer influence have a significant effect on parents' decisions to get their children vaccinated. Parents with younger children had greater vaccine hesitancy, and information framing techniques should be considered in vaccination promotion for combating such vaccine hesitancy. Future studies could be conducted to identify the moderators and mediators of information framing to facilitate its implementation.

WHAT IS KNOWN

• Parental acceptance of COVID-19 vaccine was found to be associated with various socio-economic and psychosocial factors, while the evidence on impact of vaccination characteristics was limited. • Behavioral interventions, including information framing, have been used to promote various health behaviors.

WHAT IS NEW

• Loss-framing of information on vaccine effectiveness improves vaccine acceptance, while additional information on how the vaccine reduces death does not make a difference, which can be used to inform communication with the public in vaccination promotion. • The social norm (i.e., the vaccine uptake amongst other people) is important for increasing the parental vaccine acceptance rate.