Adolescent, parent and societal preferences and willingness to pay for meningococcal B vaccine: A Discrete Choice Experiment

Preferences of US adolescents and parents for vaccination against invasive meningococcal disease

BACKGROUND

Percentage uptake of some meningococcal vaccines is low in the US. Understanding what drives vaccination preferences may help to increase vaccination rates.

OBJECTIVES

To determine how attributes of meningococcal vaccines and the availability of a pentavalent (MenABCWY) vaccine profile drive adolescents' and young people's (AYP's) willingness to be vaccinated and parents' and legal guardians' (PLG') willingness for their child to be vaccinated (WTV). To also explore how preferences for meningococcal vaccines vary by participant characteristics.

METHODS

Vaccine preferences were elicited in a discrete choice experiment (DCE) with AYP aged 16-23 years and PLG of adolescents aged 11-17 years. Participants chose between two hypothetical vaccine profiles that differed in level of protection, dosing, and risks of mild-to-moderate and severe side effects, and a no vaccination profile. Main outcome measures were relative attribute importance (RAI) and WTV. RAI measured the maximum contribution of an attribute to vaccination choice relative to other attributes. WTV compared predicted choice probabilities for the three vaccine profiles.

RESULTS

407 AYP and 394 PLG participated (50.9% male, 78.4% White/Caucasian). Irrespective of vaccine attributes, 59.5% always opted into vaccination and 3.6% always opted out of vaccination. The most important attributes were level of protection (RAI: 33.7%) and risk of mild-to-moderate side effects (RAI: 32.3%). Dosing was more important to PLG (RAI: 5.9%) than AYP (RAI: 2.0%; p < .01). Adding a pentavalent vaccine alternative increased WTV by 3.7 percentage points (PP) for PLG, 2.4 PP for AYP, 16.4 PP for vaccine-hesitant participants, 13.4 PP for participants without health insurance, and 9.6 PP for adults.

CONCLUSION

Level of protection and risk of mild-to-moderate side effects were the most important vaccine attributes. Adding a pentavalent vaccine alternative increased WTV particularly among adults, individuals who were vaccine-hesitant, and individuals without health insurance.

Quantifying Stated Preferences for Meningococcal Vaccines Among Adolescents/Young Adults and Parents of Adolescents in the United States: A Discrete Choice Experiment

INTRODUCTION

Invasive meningococcal disease (IMD) is a severe and life-threatening disease. In the United States (US), vaccine coverage with MenACWY and MenB meningococcal vaccines is suboptimal among adolescents/young adults aged 16-23 years. A combined meningococcal vaccine (MenABCWY) could increase convenience (e.g., fewer injections) and improve coverage. The objective was to quantify preferences for hypothetical meningococcal vaccine profiles among adolescents/young adults and parents.

METHODS

An online discrete choice experiment was conducted among 16- to 23-year-olds, and parents of 16- to 18-year-olds. Attributes (3 × 4) and levels (1 × 2) were based on the literature and focus groups. Participants made ten pair-wise forced trade-off choices, systematically varied using a D-optimal design. Random parameter logit quantified the relative importance of vaccination attributes and estimated the trade-offs. Differences in preferences by subgroups were assessed.

RESULTS

Totals of 300 adolescents and young adults (median age 20 years) and 300 parents (median age 46 years) completed the survey. Overall, 89.6% of 16- to 23-year-olds and 69.1% of parents preferred a simplified hypothetical meningococcal vaccination profile, e.g., with fewer injections (3 vs. 4) and fewer healthcare provider (HCP) visits (2-3 vs. 4). Having HCP advice and clear Centers for Disease Control and Prevention recommendations impacted vaccination choice, with both groups reporting high trust in HCP information (83.3% among 16- to 23-year-olds; 98.7% among parents). Barriers to vaccination included lack of HCP advice or awareness of meningococcal vaccines, and income level and out-of-pocket costs for parents.

CONCLUSIONS

Adolescents/young adults and parents demonstrated a significant preference for a meningococcal vaccine that is more convenient (such as combined MenABCWY). Parents' vaccination preferences differed by income level and out-of-pocket costs, suggesting financial barriers to vaccination may exist which could result in IMD prevention inequalities. Findings from this study provide important information to support patient-facing informed policy discussions. A simplified vaccination schedule and strong recommendation could help improve vaccine uptake, schedule compliance, disease prevention, and reduce inequalities in IMD risk and prevention. A graphical abstract is available with this article.

Preferences regarding COVID-19 vaccination among 12,000 adults in China: A cross-sectional discrete choice experiment

Understanding public preferences concerning vaccination is critical to inform pandemic response strategies. To investigate Chinese adults' preferences regarding COVID-19 vaccine attributes, we conducted a cross-sectional online survey in 12,000 Chinese adults in June-July, 2021. Participants were requested to answer a series of discrete choice questions related to hypothetical COVID-19 vaccines. Using mixed logit models, our analysis revealed that participants had a higher preference for COVID-19 vaccines with longer duration of protection (coefficient: 1.272, 95% confidence interval [1.016 to 1.529]) and higher efficacy (coefficient: 1.063, [0.840, 1.287]). Conversely, participants demonstrated a lower preference associated with higher risk of rare but serious side-effects (coefficient: -1.158, [-1.359, -0.958]), oral administration (coefficient: -0.211, [-0.377, -0.046]), more doses (coefficient: -0.148, [-0.296, 0.000]) and imported origin (coefficient: -0.653, [-0.864, -0.443]). Moreover, preferences were heterogeneous by individual factors: highly educated participants were more sensitive to the negative vaccine attributes including price (coefficient -0.312, [-0.370, -0.253]) and imported vaccine (coefficient -0.941, [-1.186, -0.697]); there was also substantial heterogeneity in vaccine preferences with respect to age group, marital status, work status, income, chronic diagnosis history, COVID-19 vaccination history and geographic regions. As the first study of examining the public preferences for COVID-19 vaccine in China with a large nationwide sample of 12,000 adults, our results indicate that future vaccine should pose lower risk, possess longer protection period, have higher efficacy, be domestically produced, and have lower costs to increase the COVID-19 vaccination coverage. Our current study findings from this study provide insights and recommendations for not only COVID-19 vaccine design but also vaccine attribute preferences to increase vaccine uptake in potential future pandemics.

From Qualitative Research to Quantitative Preference Elicitation: An Example in Invasive Meningococcal Disease

BACKGROUND

Qualitative research is fundamental for designing discrete choice experiments (DCEs) but is often underreported in the preference literature. We developed a DCE to elicit preferences for vaccination against invasive meningococcal disease (IMD) among adolescents and young people (AYP) and parents and legal guardians (PLG) in the United States. This article reports the targeted literature review and qualitative interviews that informed the DCE design and demonstrates how to apply the recent reporting guidelines for qualitative developmental work in preference studies.

METHODS

This study included two parts: a targeted literature review and qualitative interviews. The Medline and Embase databases were searched for quantitative and qualitative studies on IMD and immunization. The results of the targeted literature review informed a qualitative interview guide. Sixty-minute, online, semi-structured interviews with AYP and PLG were used to identify themes related to willingness to be vaccinated against IMD. Participants were recruited through a third-party recruiter's database and commercial online panels. Interviews included vignettes about IMD and vaccinations and three thresholding exercises examining the effect of incidence rate, disability rate, and fatality rate on vaccination preferences. Participant responses related to the themes were counted.

RESULTS

The targeted literature review identified 31 concepts that were synthesized into six topics for the qualitative interviews. Twenty AYP aged 16-23 years and 20 PLG of adolescents aged 11-17 years were interviewed. Four themes related to willingness to be vaccinated emerged: attitudes towards vaccination, knowledge and information, perception of IMD, and vaccine attributes. Most participants were concerned about IMD (AYP 60%; PLG 85%) and had positive views of vaccination (AYP 80%; PLG 60%). Ninety percent of AYP and 75% of PLG always chose vaccination over no vaccination, independent of IMD incidence rate, disability rate, or fatality rate.

CONCLUSION

Willingness to be vaccinated against IMD was affected by vaccine attributes but largely insensitive to IMD incidence and severity. This article provides an example of how to apply the recent reporting guidelines for qualitative developmental work in preference studies, with 21 out of 22 items in the guidelines being considered.

Nurses' preferences regarding MenACWY conjugate vaccines attributes: a discrete choice experiment in Spain

OBJECTIVES

Immunisation against preventable diseases as meningitis is crucial from a public health perspective to face challenges posed by these infections. Nurses hold a great responsibility for these programs, which highlights the importance of understanding their preferences and needs to improve the success of campaigns. This study aimed to investigate nurses' preferences regarding Meningococcus A, C, W, and Y (MenACWY) conjugate vaccines commercialised in Spain.

STUDY DESIGN

A national-level discrete choice experiment (DCE) was conducted.

METHODS

A literature review and a focus group informed the DCE design. Six attributes were included: pharmaceutical form, coadministration evidence, shelf-life, package contents, single-doses per package, and package volume. Conditional logit models quantified preferences and relative importance (RI).

RESULTS

Thirty experienced primary care nurses participated in this study. Evidence of coadministration with other vaccines was the most important attribute (RI = 43.78%), followed by package size (RI = 22.17%), pharmaceutical form (RI = 19.07%), and package content (RI = 11.80%). There was a preference for evidence of coadministration with routine vaccines (odds ratio [OR] = 2.579, 95% confidence interval [95%CI] = 2.210-3.002), smaller volumes (OR = 1.494, 95%CI = 1.264-1.767), liquid formulations (OR = 1.283, 95%CI = 1.108-1.486) and package contents including only vial/s (OR = 1.283, 95%CI = 1.108-1.486). No statistical evidence was found for the remaining attributes.

CONCLUSIONS

Evidence of coadministration with routine vaccines, easy-to-store packages, and fully liquid formulations were drivers of nurses' preferences regarding MenACWY conjugate vaccines. These findings provide valuable insights for decision-makers to optimize current campaigns.

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.

Job preferences of master of public health students in China: a discrete choice experiment

BACKGROUND

The shortage of public health personnel and the uneven distribution between urban and rural areas are thorny issues in China. Master of public health (MPH) is an integral part of public health human resources in the future, and it is of far-reaching significance to discuss their work preferences. The present study wants to investigate the job preference of MPH, understand the relative importance of different job attributes, and then put forward targeted incentive measures.

METHODS

Discrete choice experiment (DCE) was used to evaluate the job preference of MPHs in two medical colleges in Liaoning Province. Attributes include employment location, bianzhi, working environment, career development prospects, work value and monthly income. Thirty-six choice sets were developed using a fractional factorial design. Mixed logit models were used to analysis the DCE data.

RESULTS

The final sample comprised 327 MPHs. All the attributes and levels included in the study are statistically significant. Monthly income is the most important factor for MPHs. For non-economic factors, they value career development prospects most, followed by the employment location. Respondents' preferences are heterogeneous and influenced by individual characteristics. Subgroup analysis showed that respondents from different family backgrounds have different job preferences. Policy simulation suggested that respondents were most sensitive to a salary increase, and the combination of several non-economic factors can also achieve the same effect.

CONCLUSIONS

Economic factors and non-economic factors significantly affect the job preference of MPHs. To alleviate the shortage and uneven distribution of public health personnel, more effective policy intervention should comprehensively consider the incentive measures of the work itself and pay attention to the individual characteristics and family backgrounds of the target object.

The impacts of altruism levels on the job preferences of medical students: a cross-sectional study in China

BACKGROUND

Rational allocation of human resources for health is crucial for ensuring public welfare and equitable access to health services. Understanding medical students' job preferences could help develop effective strategies for the recruitment and retention of the health workforce. Most studies explore the relationship between extrinsic incentives and job choices through discrete choice experiments (DCEs). Little attention has been paid to the influence of intrinsic altruism on job choice. This study aimed to explore the heterogeneous preferences of medical students with different levels of altruism regarding extrinsic job attributes.

METHODS

We conducted an online survey with 925 medical students from six hospitals in Beijing from July to September 2021. The survey combined job-choice scenarios through DCEs and a simulation of a laboratory experiment on medical decision-making behavior. Behavioral data were used to quantify altruism levels by estimating altruistic parameters based on a utility function. We fit mixed logit models to estimate the effects of altruism on job preference.

RESULTS

All attribute levels had the expected effect on job preferences, among which monthly income (importance weight was 30.46%, 95% CI 29.25%-31.67%) and work location (importance weight was 22.39%, 95% CI 21.14%-23.64%) were the most salient factors. The mean altruistic parameter was 0.84 (s.d. 0.19), indicating that medical students' altruism was generally high. The subgroup analysis showed that individuals with higher altruism levels had a greater preference for non-financial incentives such as an excellent work environment, sufficient training and career development opportunities, and a light workload. The change in the rate of the uptake of a rural position by individuals with lower levels of altruism is sensitive to changes in financial incentives.

CONCLUSIONS

Medical students' altruism was generally high, and those with higher altruism paid more attention to non-financial incentives. This suggests that policymakers and hospital managers should further focus on nonfinancial incentives to better motivate altruistic physicians, in addition to appropriate economic incentive when designing recruitment and retention interventions. Medical school administrations could attach importance to the promotion of altruistic values in medical education.

Understanding barriers to vaccination against invasive meningococcal disease: a survey of the knowledge gap and potential solutions

INTRODUCTION

Invasive meningococcal disease (IMD) is a leading cause of life-threatening bacterial meningitis and septicemia. Evidence points to a knowledge gap among parents, teenagers, and healthcare providers (HCPs) regarding IMD and available vaccines, including those against the highly prevalent serogroup B.

AREAS COVERED

An online survey was conducted between March 27 and April 12, 2019, to gather insights into the knowledge that parents/guardians have about IMD vaccines. The children were aged 2 months-10 years in Australia, Brazil, Germany, Greece, Italy, and Spain, 5-20 years in the UK, and 16-23 years in the US. The findings were discussed in the context of the available literature and solutions were proposed to minimize the knowledge gap and the barriers to vaccination against IMD.

EXPERT OPINION

The survey demonstrated that parents have a good understanding of IMD but a limited understanding of the different serogroups and vaccines. The available literature highlighted multiple barriers to IMD vaccine uptake; these may be reduced through education of HCPs, clear recommendations to parents by HCPs, the use of technology, and disease-awareness initiatives that engage parents through physical and digital channels. Further studies are warranted to assess the impact of the COVID-19 pandemic on IMD vaccination.

Consumer Attitudes and Preferences for Healthy Boxed Meal Attributes in Taiwan: Evidence from a Choice Experiment

Consumers have realized the importance of a healthy diet, hoping to reduce the occurrence of obesity and chronic diseases. Therefore, healthy boxed meals with low calories and high protein are gaining attention. This study divided the attributes of healthy boxed meals into five categories, namely, taste, nutrition facts, traceability certification, carbon footprint label, and price, and investigated the relationship between consumer preferences and willingness to pay (WTP) using a choice experiment. A purposive sampling procedure was used to collect 495 valid questionnaires. The results indicate the following: (1) when purchasing healthy boxed meals, the respondents were most concerned with traceability certification and nutrition facts; (2) the respondents were willing to pay a premium for meals with traceability certification (NTD 4.6) and nutrition facts (NTD 4.4); (3) respondents > 40 years with an average monthly salary of > NTD 30,000 who worked out regularly and were in the process of muscle building, fat loss, or weight control had higher WTP for meals with nutrition labels; and (4) female respondents who were 30-39 years old with a college or university education or above had higher WTP for meals with traceable ingredients. The results may help healthy boxed meal companies understand and pay attention to consumer needs, which will, in turn, provide a reference for future product development and marketing strategies.

Societal Preferences for Meningococcal B Vaccination in Children: A Discrete Choice Experiment in Spain

INTRODUCTION

Immunization is the most effective strategy for the prevention of invasive meningococcal disease caused by Neisseria meningitidis serogroup B (MenB); however, parents need to weigh the risk-benefit and financial impact of immunizing their children against MenB in the absence of a national immunization program (NIP). This study aimed to explore societal preferences (of parents and pediatricians) regarding the attributes of a MenB vaccine in Spain.

METHODS

A discrete choice experiment (DCE) based on cross-sectional surveys was carried out to determine preferences. A literature review and scientific committee determined the six attributes related to the MenB vaccine included in the DCE: vaccination age, cost, duration, percentage of protection, adverse events probability, and expert/authority recommendation. Data were analyzed using a mixed logit model. Relative importance (RI) of attributes was calculated and compared between parents and pediatricians.

RESULTS

A total of 278 parents [55.8% female, mean age 40.4 (standard deviation, SD 7.3) years] and 200 pediatricians [73.0% female, mean age 45.8 (SD 12.9) years] answered the DCE. For parents, the highest RI was attributed to vaccine cost, expert/authority recommendation, and percentage of protection (26.4%, 26.1%, and 22.9%, respectively), while for pediatricians the highest RI was assigned to percentage of protection, expert/authority recommendation, and vaccination age (27.2%, 23.7%, and 22.6%, respectively). Significant differences between parents and pediatricians were found in the RI assigned to all attributes (p < 0.001), except for vaccine recommendation.

CONCLUSION

In the decision regarding MenB vaccination, cost was a driver in parental decision-making but had a low RI for pediatricians and, conversely, vaccination age was highly valued by pediatricians but was the attribute with least importance for parents. Despite these differences, expert/authority recommendation and percentage of protection were essential criteria for both groups. These results provide relevant information about MenB vaccination, highlighting the importance of considering societal preferences for NIP inclusion.

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.

Parental preference for influenza vaccine for children in China: a discrete choice experiment

OBJECTIVES

To investigate what factors affect parents' influenza vaccination preference for their children and whether there exists preference heterogeneity among respondents in China.

DESIGN

Cross-sectional study. A discrete choice experiment was conducted. Five attributes were identified based on literature review and qualitative interviews, including protection rate, duration of vaccine-induced protection, risk of serious side effects, location of manufacturer and out-of-pocket cost.

SETTING

Multistage sampling design was used. According to geographical location and the level of economic development, 10 provinces in China were selected, and the survey was conducted at community healthcare centres or stations.

PARTICIPANTS

Parents with at least one child aged between 6 months and 5 years old were recruited and the survey was conducted via a face-to-face interview in 2019. In total, 600 parents completed the survey, and 449 who passed the internal consistency test were included in the main analysis.

MAIN OUTCOMES AND MEASURES

A mixed logit model was used to estimate factors affecting parents' preference to vaccinate their children. In addition, sociodemographic characteristics were included to explore the preference heterogeneity.

RESULTS

In general, respondents preferred to vaccinate their children. All attributes were statistically significant and among them, the risk of severe side effects was the most important attribute, followed by the protection rate and duration of vaccine-induced protection. Contrary to our initial expectation, respondents have a stronger preference for the domestic than the imported vaccine. Some preference heterogeneity among parents was also found and in particular, parents who were older, or highly educated placed a higher weight on a higher protection rate.

CONCLUSION

Vaccination safety and vaccine effectiveness are the two most important characteristics that influenced parents' decision to vaccinate against influenza for their children in China. Results from this study will facilitate future policy implementations to improve vaccination uptake rates.

The Value(s) of Vaccination: Building the Scientific Evidence According to a Value-Based Healthcare Approach

Objectives

To provide a new value-based immunization approach collating the available scientific evidence on the topic.

Methods

Four value pillars (personal, allocative, technical, and societal) applied to vaccination field were investigated. A systematic literature review was performed querying three database from December 24th, 2010 to May 27th, 2020. It included studies on vaccine-preventable diseases (VPDs) that mentioned the term value in any part and which were conducted in advanced economies. An in-depth analysis was performed on studies addressing value as key element.

Results

Overall, 107 studies were considered. Approximately half of the studies addressed value as a key element but in most of cases (83.3%) only a single pillar was assessed. Furthermore, the majority of papers addressed the technical value by looking only at classical methods for economic assessment of vaccinations whereas very few dealt with societal and allocative pillars.

Conclusions

Estimating the vaccinations value is very complex, even though their usefulness is certain. The assessment of the whole value of vaccines and vaccinations is still limited to some domains and should encompass the wider impact on economic growth and societies.

Vaccine eagerness: A new framework to analyse preferences in single profile discrete choice experiments. Application to HPV vaccination decisions among French adolescents

Background

We previously conducted a single-profile discrete choice experiment to elicit preferences of adolescents around HPV vaccine communication, finding that only half of participants made variable choices (non-uniform respondents) from which preferences were elicited. In this paper we provide a framework to evaluate post-choice certainty information to elicit preferences even among respondents who uniformly accepted (serial demanders) or refused (serial non-demanders) hypothetical vaccination scenarios.

Methods

During an in-class online questionnaire among 1458 French adolescents aged 13–15 years old, we collected certainty levels (0–10) after decisions on nine hypothetical scenarios, including four vaccination attributes: information on vaccine-preventable disease type, on vaccine safety, on potential for indirect protection and on vaccine coverage. We developed a vaccine eagerness scale (ranging from −10 to 10), by combining information on the binary decision (accept vs. refuse the hypothetical vaccine) and the decision certainty level. We used random effects linear regressions to evaluate attributes’ impact on vaccine eagerness. Sensitivity analyses were performed taking into account low response quality, assessed as invariant certainty and low response time.

Results

Attributes’ impact on decision certainty were similar between serial demanders (N = 659) and non-uniform respondents (N = 711): mentioning a positive benefit-risk balance significantly decreased certainty to accept (coefficient −0.93), while information on 80% coverage in other countries (+0.33) and potential for disease elimination (+0.09) increased it. Among serial non-demanders, significant attribute impacts were observed only after exclusion of low-quality responses (N = 31): a potential for disease elimination (coefficient: +0.24) and 80% coverage in other countries (+0.42) significantly increased certainty of refusing vaccination. Combining decision and certainty into a vaccine eagerness indicator allowed analysing preferences in the full sample, including “hesitant” respondents, who were sensitive to the content of the vaccination profile.

Conclusion

Choice certainty informs on respondents’ preferences in single-profile discrete-choice experiments, in particular among those with uniform responses.

•

Preferences are not identified among “uniform respondents” in single profile DCEs.

•

Analysis of post-choice certainty can reveal information on their preferences.

•

We propose a new concept for DCEs on vaccination, “vaccine eagerness”.

•

Vaccine eagerness allows analyzing preferences among serial non-demanders.

Immediate and informative feedback during a pandemic: Using stated preference analysis to predict vaccine uptake rates

In response to an emerging pandemic, there is urgent need for information regarding individual evaluation of risk and preferences toward mitigation strategies such as vaccinations. However, with social distancing policies and financial stress during an outbreak, traditional robust survey methodologies of face-to-face, probabilistic sampling, may not be feasible to deploy quickly, especially in developing countries. We recommend a protocol that calls for a sensitive survey design, acceptance of a web-based approach and adjustments for uncertainty of respondents, to deliver urgently needed information to policymakers as the public health crisis unfolds, rather than in its aftermath. This information is critical to tailor comprehensive vaccination campaigns that reach critical immunity thresholds. We apply our recommendations in a regional study of 16 Latin American countries in the month following index cases of COVID-19. We use a split-sample, contingent valuation approach to evaluate the effects of cost, duration of immunity and effectiveness of the vaccine. Our results show that cost and duration of immunity are significant factors in the decision to vaccinate, while the degree of effectiveness is insignificant, unless the vaccine is 100% effective. Income as well as perceived risk and severity of the virus are important determinants also.

Vaccine preferences driving vaccine-decision making of different target groups: a systematic review of choice-based experiments

BACKGROUND

Choice-based experiments have been increasingly used to elicit preferences for vaccines and vaccination programs. This study aims to systematically identify and examine choice-based experiments assessing (differences in) vaccine preferences of vaccinees, representatives and health advisors.

METHODS

Five electronic databases were searched on choice-based conjoint analysis studies or discrete choice experiments capturing vaccine preferences of children, adolescents, parents, adults and healthcare professionals for attributes of vaccines or vaccine settings up to September 2020. Data was extracted using a standardized form covering all important aspects of choice experiments. A quality assessment was used to assess the validity of studies. Attributes were categorized into outcome, process, cost and other. The importance of attributes was assessed by the frequency of reporting and statistical significance. Results were compared between high-quality studies and lower-quality studies.

RESULTS

A total of 42 studies were included, with the majority conducted in high-income countries after 2010 (resp. n = 34 and n = 37). Preferences of representatives were studied in nearly half of the studies (47.6%), followed by vaccinees (35.7%) and health advisors (9.5%). Sixteen high-quality studies passed the quality assessment. Outcome- and cost- related attributes such as vaccine effectiveness, vaccine risk, cost and protection duration were most often statistically significant across both target groups, with vaccine effectiveness being the most important. Risks associated with vaccination, such as side effects, were more often statistically significant in studies targeting vaccinees, while cost-related attributes were more often statistically significant in studies of representatives. Process-related attributes such as vaccine accessibility and time were least important across both target groups.

CONCLUSION

To our knowledge, this is the first systematic review in which vaccine preferences of different target groups were assessed and compared. The same attributes were most important for vaccine decisions of vaccinees and representatives, with only minor differences in level of evidence for vaccine risk and cost. Future research on vaccine preferences of health advisors and/or among target groups in low-resource settings would give insight into the generalizability of current findings.

Preferences for herpes zoster vaccination among adults aged 50 years and older in the United States: results from a discrete choice experiment

BACKGROUND

Most adults, and disproportionately fewer African-Americans, have not received herpes zoster (HZ) vaccination despite current recommendations. This study (GSK study identifiers: 208677/HO-17-18066) assessed HZ vaccination preferences among adults aged ≥ 50 years.

RESEARCH DESIGN AND METHODS

In this discrete choice experiment, respondents chose among a 'no vaccine' option and two HZ vaccine profiles, characterized by seven attributes, in a series of choice questions. Random-parameters logit results were used to predict likely vaccine uptake. Subgroup and latent class analysis of African-American's preferences were performed.

RESULTS

The preference weight for choosing HZ vaccines over no vaccine was statistically significant among the 1,454 respondents (71.9% whites; 25.2% African-Americans). Out-of-pocket (OOP) cost and vaccine effectiveness (VE) were the most important attributes. The African-American and the non-African-American subgroups had statistically significant differences in preferences (χ² = 59.91, p < 0.001), mainly driven by OOP cost and VE. Latent class analysis identified three groups of African-American respondents with systematically different preferences; two comprised likely-vaccinators, with one being more cost sensitive at lower price thresholds, and one likely non-vaccinators.

CONCLUSIONS

For all respondents, HZ vaccine choices were most sensitive to total OOP cost, followed by VE.

Optimising HPV vaccination communication to adolescents: A discrete choice experiment

BACKGROUND

Human Papillomavirus (HPV) vaccine coverage in France is below 30%, despite proven effectiveness against HPV infections and (pre-)cancerous cervical lesions. To optimise vaccine promotion among adolescents, we used a discrete choice experiment (DCE) to identify optimal statements regarding a vaccination programme, including vaccine characteristics.

METHODS

Girls and boys enrolled in the last two years of five middle schools in three French regions (aged 13-15 years) participated in an in-class cross-sectional self-administered internet-based study. In ten hypothetical scenarios, participants decided for or against signing up for a school-based vaccination campaign against an unnamed disease. Scenarios included different levels of four attributes: the type of vaccine-preventable disease, communication on vaccine safety, potential for indirect protection, and information on vaccine uptake among peers. One scenario was repeated with an added mention of sexual transmission.

RESULTS

The 1,458 participating adolescents (estimated response rate: 89.4%) theoretically accepted vaccination in 80.1% of scenarios. All attributes significantly impacted theoretical vaccine acceptance. Compared to a febrile respiratory disease, protection against cancer was motivating (odds ratio (OR) 1.29 [95%-CI 1.09-1.52]), but not against genital warts (OR 0.91 [0.78-1.06]). Compared to risk negation ("vaccine does not provoke serious side effects"), a reference to a positive benefit-risk balance despite a confirmed side effect was strongly dissuasive (OR 0.30 [0.24-0.36]), while reference to ongoing international pharmacovigilance without any scientifically confirmed effect was not significantly dissuasive (OR 0.86 [0.71-1.04]). The potential for indirect protection motivated acceptance among girls but not boys (potential for eliminating the disease compared to no indirect protection, OR 1.57 [1.25-1.96]). Compared to mentioning "insufficient coverage", reporting that ">80% of young people in other countries got vaccinated" motivated vaccine acceptance (OR 1.94 [1.61-2.35]). The notion of sexual transmission did not influence acceptance.

CONCLUSION

HPV vaccine communication to adolescents can be tailored to optimise the impact of promotion efforts.

Methods for Conducting Stated Preference Research with Children and Adolescents in Health: A Scoping Review of the Application of Discrete Choice Experiments

BACKGROUND

Discrete choice experiments (DCEs) are a common method used to describe and quantitatively assess preferences in health applications. Increasingly, DCEs have been used to elicit preferences from children and adolescents and generate evidence to inform policies affecting this population.

OBJECTIVES

The aim of this review was to summarize and describe the application of DCEs conducted with children and adolescents and describe author-reported age-specific considerations in design, implementation, and analysis.

METHODS

A scoping review was conducted using a 'pearl-growing' technique whereby the reference lists of existing systematic reviews of DCEs were used to identify potential studies conducted with children or adolescents as respondents published between 1990 and 2017. This list was supplemented with an updated electronic search using the same strategy as the initial reviews to identify studies from 2017 to 2020.

RESULTS

Of 480 studies identified, 19 were included; topics included vaccines (32%), drugs/medical devices (26%), treatment or health promotion interventions/programs (21%), warning labels on cigarettes/nicotine products (10%), and preferences for physical activity and healthy food choices (10%). The youngest reported age for independent DCE completion was 8 years. Approaches to assessing validity and reliability of choices were consistent with best practices for the conduct of DCEs. Reported age-specific considerations included use of visual aids, age-appropriate language, reducing task complexity and cognitive burden, and exploration of interpretation of willingness-to-pay.

CONCLUSION

The number of DCEs conducted with children and adolescents has increased in recent years. Detailed explanation of why reported age-specific considerations were necessary, how they could be used to interpret results, or to understand the appropriateness of this methodology for different age groups was limited. Despite a recognition of the need for special consideration when conducting DCEs in this population, the unique issues in the context of age-specific considerations are largely unexplored, and further research is required. Moving forward, stated preference research conducted with children and adolescents should report in more detail methods of recruitment, results of validity assessments, and provide specific reflection on the extent to which modeled results are consistent with expectations and underlying theory.

Public attitudes toward COVID-19 vaccination: The role of vaccine attributes, incentives, and misinformation

While efficacious vaccines have been developed to inoculate against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; also known as COVID-19), public vaccine hesitancy could still undermine efforts to combat the pandemic. Employing a survey of 1096 adult Americans recruited via the Lucid platform, we examined the relationships between vaccine attributes, proposed policy interventions such as financial incentives, and misinformation on public vaccination preferences. Higher degrees of vaccine efficacy significantly increased individuals' willingness to receive a COVID-19 vaccine, while a high incidence of minor side effects, a co-pay, and Emergency Use Authorization to fast-track the vaccine decreased willingness. The vaccine manufacturer had no influence on public willingness to vaccinate. We also found no evidence that belief in misinformation about COVID-19 treatments was positively associated with vaccine hesitancy. The findings have implications for public health strategies intending to increase levels of community vaccination.

Preference of influenza vaccination among the elderly population in Shaanxi province, China

The influenza vaccination uptake rate is low in China. In the current study, we aimed to explore the preferences of influenza vaccination among the Chinese elderly. A discrete choice experiment design was performed to assess their preferences toward five influenza vaccination attributes, including vaccine effectiveness, duration of protection, severe adverse effects, vaccination cost, and vaccination recommendation source. A total of 144 participants aged over 60 years from three cities of Shaanxi province in China were surveyed. A mixed logit model was employed to analyze the data. The elderly population were found to prefer influenza vaccination with a longer duration of protection, followed by lower severe adverse effects, higher vaccine effectiveness, and recommended by healthcare providers. The vaccination cost was the least important attribute. The most considerable marginal willingness to pay for vaccination (CNY220.90) and the highest vaccination choice probability (83.70%) occurred when the duration of protection extended from 3 to 12 months. The present study's findings would inform decision-makers on implementing appropriate interventions for the increase of influenza vaccination coverage among the elderly in China.

Parents' willingness to pay for a COVID-19 vaccine for themselves and their children in the United States

Differences in obtaining a vaccine vary based on a multitude of factors including perceptions of vaccine safety, efficacy and willingness to pay (WTP). This study focuses on parent perceptions toward a vaccine for COVID-19 including their WTP decisions for their children and themselves. A mixed methods design using a cross-sectional survey was used to assess the perceptions of US parents, with children under 18, in response to the COVID-19 pandemic. The survey was administered online in November 2020 and 584 final responses were collected. The questionnaire consisted of approximately 37 closed and open-ended questions regarding personal background information; awareness, knowledge, and experience of the virus; perception toward vaccines and COVID-19; and the contingent valuation of a hypothetical COVID-19 vaccine. WTP was found to be higher for children and a direct relationship between the number of children and WTP was observed. Parents were willing to pay US$228-$291 for a vaccine for themselves and US$243-US$321 for their children. A positive impact on WTP was found with self-reported parent health status but not children. The findings of this study have important implications for policy programs which require detailed cost-benefit analyses. WTP for a COVID-19 vaccine is crucial to determine the partial benefits of vaccinating to reduce the risk of repetitive widespread outbreaks.

Preferences for a COVID-19 vaccine in Australia

In absence of a COVID-19 vaccine, testing, contact tracing and social restrictions are among the most powerful strategies adopted around the world to slow down the spread of the pandemic. Citizens of most countries are suffering major physical, psychological and economic distress. At this stage, a safe and effective COVID-19 vaccine is the most sustainable option to manage the current pandemic. However, vaccine hesitancy by even a small subset of the population can undermine the success of this strategy.

The objective of this research is to investigate the vaccine characteristics that matter the most to Australian citizens and to explore the potential uptake of a COVID-19 vaccine in Australia. Through a stated preference experiment, preferences towards a COVID-19 vaccine of 2136 residents of the Australian states and territories were collected and analysed via a latent class model.

Results show that preferences for mild adverse cases, mode of administration, location of administration, price and effectiveness are heterogeneous. Conversely, preferences for immediacy and severe reactions are homogeneous, with respondents preferring a shorter period until vaccine is available and lower instances of severe side effects. The expected uptake of the vaccine is estimated under three different scenarios, with the value of 86% obtained for an average scenario. By calculating individual preferences, the willingness to pay is estimated for immediacy, effectiveness, mild and severe side effects.

Parental Vaccine Preferences for Their Children in China: A Discrete Choice Experiment

Vaccination is one of the most cost-effective health investments to prevent and control communicable diseases. Improving the vaccination rate of children is important for all nations, and for China in particular since the advent of the two-child policy. This study aims to elicit the stated preference of parents for vaccination following recent vaccine-related incidents in China. Potential preference heterogeneity was also explored among respondents. Methods: A discrete choice experiment was developed to elicit parental preferences regarding the key features of vaccines in 2019. The study recruited a national sample of parents from 10 provinces who had at least one child aged between 6 months and 5 years old. A conditional logit model and a mixed logit model were used to estimate parental preference. Results: A total of 598 parents completed the questionnaire; among them, 428 respondents who passed the rational tests were analyzed. All attributes except for the severity of diseases prevented by vaccines were statistically significant. The risk of severe side effects and protection rates were the two most important factors explaining parents’ decisions about vaccination. The results of the mixed logit model with interactions indicate that fathers or rural parents were more likely to vaccinate their children, and children whose health was not good were also more likely to be vaccinated. In addition, parents who were not more than 30 years old had a stronger preference for efficiency, and well-educated parents preferred imported vaccines with the lowest risk of severe side effects. Conclusion: When deciding about vaccinations for their children, parents in China are mostly driven by vaccination safety and vaccine effectiveness and were not affected by the severity of diseases. These findings will be useful for increasing the acceptability of vaccination in China.

Contingent assessment of the COVID-19 vaccine

The COVID-19 pandemic has not only had a negative impact on people's health and life behavior, but also on economies around the world. At the same time, laboratories and institutions are working hard to obtain a COVID-19 vaccine, which we hope will be available soon. However, there has been no assessment of whether an individual and society value ​​a vaccine monetarily, and what factors determine this value. Therefore, the objective of this research was to estimate the individual's willingness to pay (WTP) for a hypothetical COVID-19 vaccine and, at the same time, find the main factors that determine this valuation. For this, we used the contingent valuation approach, in its single and double-bounded dichotomous choice format, which was based on a hypothetical market for a vaccine. The sample used was obtained through an online survey of n = 566 individuals from Chile. The main results showed that the WTP depends on the preexistence of chronic disease (p≤0.05), knowledge of COVID-19 (p≤0.05), being sick with COVID-19 (p≤0.05), perception of government performance (p≤0.01), employment status (p≤0.01), income (p≤0.01), health care (p≤0.05), adaptation to quarantine with children at home (p≤0.01) and whether the person has recovered from COVID-19 (p≤0.10). According to our discrete choice model in double-bounded dichotomous format, it was concluded that the individuals' WTP is US$184.72 (CI: 165.52-203.92; p < 0.01). This implies a social valuation of approximately US$2232 million, corresponding to 1.09% of the GNP per capita.

Preferences of Patients with Non-Communicable Diseases for Primary Healthcare Facilities: A Discrete Choice Experiment in Wuhan, China

Objectives: To elicit stated preferences of patients with non-communicable diseases (NCDs) for primary healthcare (PHC) facilities and to explore the willingness-to-pay (WTP) for facility attributes. Methods: A discrete choice experiment (DCE) was conducted through face to face interviews. The DCE survey was constructed by five attributes: type of service, treatment measures, cost, travel time, and care provider. Patients’ preferences and willingness to pay for facility attributes were analyzed using a mixed logit model, and interaction terms were used to assess preference heterogeneity among patients with different sociodemographic characteristics. Results: Patients placed different weights on attributes, depending on whether they perceived their health condition as minor or severe. For conditions perceived as minor, patients valued treatment measures (56.60%), travel time (32.34%) and care provider (8.51%) most. For conditions perceived as severe, they valued treatment measures (52.19%), care provider (38.69%), and type of service (7.30%) most. The WTP related to the change from Traditional Chinese Medicine (TCM) service to Modern Medicine (MM) service was the largest for both severity scenarios. For conditions perceived as minor, patients would be willing to pay 102.84 CNY (15.43 USD) for a reduction in travel time to below 30 min. For conditions perceived as severe, WTP related to the change from general service to specialized service and from junior medical practitioner to senior medical practitioner, were highly valued by respondents, worth 107.3 CNY (16.10 USD) and 565.8 CNY (84.87 USD), respectively. Conclusions: Factors related to the provision of PHC, such as treatment measures, care provider and type of service were highly valued. The findings could contribute to the design of better PHC delivery, improve the participation of patients in PHC, and provide some evidence to promote shared decision-making.

Meningococcal Group B Vaccine For The Prevention Of Invasive Meningococcal Disease Caused By Neisseria meningitidis Serogroup B

Invasive meningococcal disease (IMD) is a major public health concern because of its high case fatality, long-term morbidity, and potential to course with outbreaks. IMD caused by Nesseira meningitidis serogroup B has been predominant in different regions of the world like Europe and only recently broadly protective vaccines against B serogroup have become available. Two protein-based vaccines, namely 4CMenB (Bexsero®) and rLP2086 (Trumenba®) are currently licensed for use in different countries against MenB disease. These vaccines came from a novel technology on vaccine design (or antigen selection) using highly specific antigen targets identified through whole-genome sequence analysis. Moreover, it has the potential to confer protection against non-B meningococcus and against other Neisserial species such as gonococcus. Real-world data on the vaccine-use are rapidly accumulating from the UK and other countries which used the vaccine for control of outbreak or as part of routine immunization program, reiterating its safety and efficacy. Additional data on real-life effectiveness, long-term immunity, and eventual herd effects, including estimates on vaccine impact for cost-effectiveness assessment are further needed. Given the predominance of MenB in Europe and other parts of the world, these new vaccines are crucial for the prevention and public health control of the disease, and should be considered.

Preferences for cervical cancer screening service attributes in rural China: a discrete choice experiment

Objectives: Compared with other cancers, screening for cervical cancer is highly cost-effective. However, due to limited awareness about cervical cancer and many other factors, women's attendance rate in rural China for cervical cancer screening remains low. This study aimed to determine women's preferences for cervical cancer screening, to help enhance screening uptake. Methods: A discrete choice experiment (DCE) was conducted among a population-based random sample of 420 women (30-65 years old) in August 2015. Attributes included the percentage of cervical cancer-related death reduction, screening interval, screening location, screening pain, waiting time for screening results and out-of-pocket costs. Mixed logit models were used to analyze the relative importance of each screening attribute. Results: When considering a screening program, the screening cost, location and the percentage of cervical cancer-related death reduction were of most concern to women. Among the presented attributes, the pain associated with the process of screening was of the least concern. Conclusions: All six attributes in our study were found to have a large influence on the preference for cervical cancer screening, and significant preference heterogeneity existed among participants. The findings indicate that the maintenance of a free screening program is essential to increasing screening uptake in this vulnerable population.

Development of a Discrete-Choice Experiment (DCE) to Elicit Adolescent and Parent Preferences for Hypodontia Treatment

Objective

Our objective was to develop and test a discrete-choice experiment (DCE) survey to elicit adolescent and parent preferences for dental care for hypodontia (a developmental condition where one or more teeth fail to develop).

Methods

This was a mixed-methods study. Participants were adolescents (aged 12–16 years) with hypodontia and their parents and the dentists providing hypodontia care. Stage one entailed attribute development, as follows. (1) Attribute identification: systematic review of hypodontia literature; interviews with adolescents with hypodontia (n = 8) and parents (n = 8); observation of hypodontia clinical consultations (n = 5); environmental scan of hypodontia patient information resources (n = 30); and systematic analysis of social media posts (n = 176). (2) Attribute selection: stakeholder consultation to develop items for a questionnaire; rating and ranking questionnaire for adolescents with hypodontia and parents (n = 18); further stakeholder consultation. Stage two involved the development of the DCE survey, and stage three included the pre-testing using cognitive interviews with adolescents (n = 12) and parents (n = 8) to assess face and content validity.

Results

The attribute long list included 27 attributes focusing on service delivery and treatment outcome, from which seven ‘important’ attributes were selected for pre-testing. Cognitive interviewing suggested adolescents found the DCE choice tasks challenging to understand; the survey was modified to enhance its acceptability. One attribute was excluded as it showed poor validity with adolescents. Pre-testing suggested DCE choice tasks encouraged thinking and discussion about preferences for treatment.

Conclusions

Including the target respondent group in all stages of DCE development ensured the final DCE survey was valid and acceptable. DCE methods appear to be a useful tool for exploring joint decision making alongside conventional preference elicitation.

Electronic supplementary material

The online version of this article (10.1007/s40271-018-0338-0) contains supplementary material, which is available to authorized users.

Discrete Choice Experiments in Health Economics: Past, Present and Future

OBJECTIVES

Discrete choice experiments (DCEs) are increasingly advocated as a way to quantify preferences for health. However, increasing support does not necessarily result in increasing quality. Although specific reviews have been conducted in certain contexts, there exists no recent description of the general state of the science of health-related DCEs. The aim of this paper was to update prior reviews (1990-2012), to identify all health-related DCEs and to provide a description of trends, current practice and future challenges.

METHODS

A systematic literature review was conducted to identify health-related empirical DCEs published between 2013 and 2017. The search strategy and data extraction replicated prior reviews to allow the reporting of trends, although additional extraction fields were incorporated.

RESULTS

Of the 7877 abstracts generated, 301 studies met the inclusion criteria and underwent data extraction. In general, the total number of DCEs per year continued to increase, with broader areas of application and increased geographic scope. Studies reported using more sophisticated designs (e.g. D-efficient) with associated software (e.g. Ngene). The trend towards using more sophisticated econometric models also continued. However, many studies presented sophisticated methods with insufficient detail. Qualitative research methods continued to be a popular approach for identifying attributes and levels.

CONCLUSIONS

The use of empirical DCEs in health economics continues to grow. However, inadequate reporting of methodological details inhibits quality assessment. This may reduce decision-makers' confidence in results and their ability to act on the findings. How and when to integrate health-related DCE outcomes into decision-making remains an important area for future research.

Job preferences for healthcare administration students in China: A discrete choice experiment

Background

There is a deficiency of healthcare administrators in China as compared with other countries; furthermore, the distribution is unequal. To inform an effective policy intervention, it is crucial to understand healthcare administration students’ career decision-making. This study aims to investigate the undergraduate students’ stated preferences when choosing a job.

Methods

A discrete choice experiment (DCE) was conducted among a population-based multistage sample of 668 final year undergraduate healthcare administration students during April to June 2017 in eight universities of China to elicit their job preferences. Attributes include location, monthly income, bianzhi (which refers to the established posts and can be loosely regarded as state administrative staffing), training and career development opportunity, working environment and workload. Conditional and mixed logit models were used to analyze the relative importance of job attributes.

Results

All six attributes were statistically significant with the expected sign and demonstrated the existence of preference heterogeneity. Monthly income, workload and working environment were of most concern to healthcare administration students when deciding their future. Among the presented attributes bianzhi was of the least concern. Sub-group analysis showed that students who have an urban background and/or with higher annual family incomes were willing to pay more for working in the city. In addition, students from western and middle universities valued bianzhi higher than students from eastern universities.

Conclusions

This is the first study focusing on the career decision-making of Chinese healthcare administration students at a critical career decision-making point. Both monetary and non-monetary interventions could be considered by policy-makers to attract students to work in health institutions, especially in rural and remote health institutions in China. There exists preference heterogeneity on healthcare administration students’ job preferences, which should also be taken into account in developing more effective policy incentive packages.

Parental awareness of Meningococcal B vaccines and willingness to vaccinate their teens

Background:

In the US, Meningococcal B (MenB) vaccines were first licensed in 2014. In 2015, the Advisory Committee on Immunization Practices recommended that parents of teens talk to their provider about receiving MenB vaccine, rather than issuing a routine recommendation. We assessed parental awareness of MenB vaccines and willingness to vaccinate their teens with MenB vaccines compared to MenACWY vaccines, which have been routinely recommended for many years.

Methods:

We surveyed parents of teens attending high school in 2017–18 during the Minnesota State Fair. Parents reported via iPad their knowledge of and concern about meningococcal disease and their awareness of and willingness to vaccinate with MenB and MenACWY vaccines. We assessed the relationship between meningococcal disease knowledge and concern, MenB and MenACWY vaccine awareness, and willingness to vaccinate with MenB and MenACWY using adjusted logistic regression.

Results:

Among 445 parents, the majority had not heard of the newly introduced MenB vaccines Bexsero^® (80.0%; 95% CI: 76.0–83.6) or Trumenba^® (82.0%; 95% CI: 78.1–85.5) or the MenACWY vaccines Menactra^® or Menveo^® (68.8%; 95% CI: 64.2–73.0). The majority were at least somewhat willing to vaccinate their teen with MenB vaccine (89.6%; 95% CI: 86.5, 92.3) and MenACWY vaccine (91.2%; 95% CI: 88.2, 93.7). Awareness of MenB vaccines (OR: 3.8; 95% CI: 1.2–12.2) and concern about meningococcal disease (OR: 3.1; 95% CI: 1.5–6.3) were significantly associated with willingness to vaccinate with MenB vaccine.

Conclusions:

Awareness of MenB vaccine is lacking among parents of teens but is an important predictor of willingness to vaccinate with the newly licensed MenB vaccines.

Measuring Health-Related Quality of Life in Adolescent Populations: An Empirical Comparison of the CHU9D and the PedsQLTM 4.0 Short Form 15

OBJECTIVE

The aim was to conduct an empirical assessment of the measurement properties of the preference-based Child Health Utility 9D (CHU9D) versus the non-preference-based Pediatric Quality of Life Inventory (PedsQL)™ 4.0 Short Form 15 Generic Core Scales (referred to as 'PedsQL') in an Australian community-based sample of adolescents.

METHODS

An online survey including the CHU9D, the PedsQL, a self-reported general health question, and socio-demographic questions was administered to adolescents (aged 15-17 years). Descriptive summary statistics and psychometric analyses were conducted to assess levels of agreement and convergent validity between the instruments.

RESULTS

A total of 775 adolescents (mean ± SD age 15.8 ± 0.8 years) completed the survey. The mean ± SD scores of the CHU9D and the PedsQL were 0.72 ± 0.22 and 72.86 ± 16.56, respectively. For both instruments, there were significant differences in health-related quality of life scores according to self-reported health status and socio-economic status. Overall, both the Spearman's correlation (r = 0.63) and the intraclass correlation coefficient (0.77) suggested a high level of agreement.

CONCLUSIONS

The findings indicate good levels of agreement overall between the CHU9D and PedsQL and provide further support for the validity of the application of the CHU9D in the economic evaluation of adolescent health care treatment and service programmes.

Assessing Rationality in Discrete Choice Experiments in Health: An Investigation into the Use of Dominance Tests

BACKGROUND

Dominance tests are often applied to test for the rationality in the choice behavior of participants in discrete choice experiments (DCEs).

OBJECTIVES

To examine how dominance tests have been implemented in recent DCE applications in health and discuss their theoretical and empirical interpretation.

METHODS

Health-related DCEs published in 2015 were reviewed for the inclusion of tests on choice behavior. For studies that implemented a dominance test, information on application and interpretation of the test was extracted. Authors were contacted for test choice sets and observed proportions of subjects who chose the dominated option. Coefficients corresponding to the choice set were extracted to estimate the expected probability of choosing the dominated option with a logistic model and compared with the observed proportion. The theoretical range of expected probabilities of possible dominance tests was calculated.

RESULTS

Of 112 health-related DCEs, 49% included at least one test for choice behavior; 28 studies (25%) included a dominance test. The proportion of subjects in each study who chose the dominated option ranged from 0% to 21%. In 46% of the studies, the dominance test led to the exclusion of participants. In the 15 choice sets that were analyzed, 2 had larger proportions of participants choosing the dominated option than expected (P < 0.05).

CONCLUSIONS

Although dominance tests are frequently applied in DCEs, there is no consensus on how to account for them in data analysis and interpretation. Comparison of expected and observed proportions of participants failing the test might be indicative of DCE quality.

Individual Preferences for Child and Adolescent Vaccine Attributes: A Systematic Review of the Stated Preference Literature

BACKGROUND

Discrete choice experiments are increasingly used to assess preferences for vaccines and vaccine service delivery.

OBJECTIVES

To synthesize and critically assess the application of discrete choice experiments in childhood/adolescent vaccines, to describe how discrete choice experiments have been applied to understand preferences, and to evaluate the use of discrete choice experiment data to inform estimates of vaccine uptake.

METHODS

We conducted a systematic review of six electronic databases. Included studies were discrete choice experiments and conjoint analyses published from 2000 to 2016 related to childhood/adolescent vaccines where respondents were parents, children/adolescents, or service providers. Validity assessment was used to assess study quality and risk of bias.

RESULTS

In total, 27 articles were included, representing 21 different studies. A majority of articles were published between 2011 and 2016. Vaccines studied included human papillomavirus (24%), influenza (19%), meningococcal vaccines (14%), childhood vaccines (14%), hypothetical vaccines (10%), hepatitis B (5%), and diphtheria, tetanus, pertussis, hepatitis B, poliomyelitis, and Haemophilus influenzae type b (5%). Most studies assessed parent preferences (67%). The most common attributes were risk (24%), degree/duration of protection (21%), and cost (15%). Commonly reported outcome measures were estimates of uptake (33%), willingness-to-pay (22%), and other marginal rates of substitution (14%). Validity assessments yielded high scores overall. Areas of weakness included low response rates, inefficient experimental design, and failure to conduct formative qualitative work and a pilot of the discrete choice experiment.

CONCLUSION

This is the first systematic review of childhood/adolescent vaccine-related discrete choice experiments. In future, special attention should be paid to ensuring that choice context and discrete choice experiment design are compatible to generate reliable estimates of uptake.

Spontanuous Demand For Meningococcal B Vaccination: Effects On Appropriateness And Timing

When the meningococcus B vaccine was introduced into Italy in 2017, it was recommended for newborns based on national epidemiological data indicating that they were at greater risk. However, the vaccination service of the local health authority of L'Aquila had already been receiving spontaneous parental requests to provide vaccination for children in lower-risk age groups from the beginning of 2016. We therefore decided to use a self-administered questionnaire in order to investigate the parents’ socio-demographic data; their children's history of other recommended vaccinations (against measles, mumps and rubella, varicella, meningococcus C and, for females, human papilloma virus); the information sources concerning meningococcal vaccination; and the timing of its administration.

The questionnaire was completed by 565 parents, and the results showed that the requests mainly came from the parents of children aged 5–11 years. The children whose mothers had received a high school education and were >35 years old were more likely to have received the first dose after the age of one year and to have perceived pain at the inoculation site, and less likely to have experienced mild general reactions. The requests were mainly trigged by the recommendations of healthcare professionals, and the overloading of the vaccination service led to delays in the administration of the doses after the first. The delays (reported by 74.07% of the parents) were mainly due to organisational problems in the service itself, which led 61.52% of the doses being more appropriately administered by staff working as private physicians inside public health facilities, albeit at extra cost.

These findings indicate that organisational factors and excessive demand had a considerable impact on both the efficacy of the immunisation and its appropriateness.

The views of the general public on prioritising vaccination programmes against childhood diseases: A qualitative study

BACKGROUND

Decisions regarding which vaccines are funded in the United Kingdom (UK) are increasingly informed by cost-effectiveness analyses. Such analyses use Quality Adjusted Life Years (QALYs) as a measure of effectiveness and assume that QALYs are equal regardless of where and in whom they occur in the population. However, there is increasing debate about whether this QALY approach is appropriate and whether societal preferences for childhood vaccinations should be used to help inform childhood immunisation policy.

OBJECTIVE

To gauge the general public's preferences for prioritising certain characteristics of childhood vaccination, to help inform future policy making decisions in the UK.

DESIGN

Qualitative design using individual face-to-face interviews, with data analysed using an inductive thematic framework approach.

SETTING

Two counties in England, UK.

POPULATION

Adult members of the general public were recruited using the Bristol and South Gloucestershire open electoral registers, using gender and deprivation quotas for each area.

PARTICIPANTS

21 members of the public participated in qualitative interviews.

RESULTS

The qualitative research identified three major themes and several key attributes that influences participant's opinions about priority setting for childhood vaccinations: (1) population segment (i.e. age group, carer impact and social group), (2) vaccine preventable diseases preferences (i.e. disease severity, disease incidence and declining infection) and (3) risks and benefits associated with childhood vaccinations (i.e. vaccine associated side-effects, herd protection and peace of mind).

CONCLUSION

Evidence from this qualitative study suggests that some members of the UK general public have more nuanced views than the health-maximisation approach when considering how childhood vaccines should be prioritised. This is not necessarily captured by the current economic approaches for assessing the benefits from childhood vaccinations in the UK, but is an important area for future research to ensure appropriate decision making.

Impact of publicly available vaccination rates on parental school and child care choice

OBJECTIVE

Several states require schools and child cares to report vaccination rates, yet little is known about the impact of these policies. Our objectives were to assess: (1) predicted impact of vaccination rates on school/child care choice, (2) differences between vaccine hesitant and non-hesitant parents, and (3) differences by child's age.

METHODS

In 2016, a cross-sectional email survey of Colorado mothers with children ≤12 years old assessed value of vaccination rates in the context of school/child care choice. A willingness-to-pay framework measured preference for schools/child cares with different vaccination rates using tradeoff with commute time.

RESULTS

Response rate was 42% (679/1630). Twelve percent of respondents were vaccine hesitant. On a scale where 1 is "not important at all" and 4 is "very important" parents rated the importance of vaccination rates at 3.08. Respondents (including vaccine-hesitant respondents) would accept longer commutes to avoid schools/child cares with lower vaccination rates. Parents of child-care-age children were more likely to consider vaccination rates important.

CONCLUSIONS

This study shows parents highly value vaccination rates in the context of school and child care choice. Both hesitant and non-hesitant parents are willing to accept longer commute times to protect their children from vaccine-preventable diseases.

Educating children and adolescents about vaccines: a review of current literature

INTRODUCTION

Until recently, research on vaccine hesitancy has focused primarily on parent populations. Although adolescent knowledge and views are gaining momentum within the literature, particularly with regards to the human papillomavirus and influenza, children remain a virtually unstudied population with regards to vaccine hesitancy.

AREAS COVERED

This review focuses on the lack of literature in this area and argues for more vaccine hesitancy research involving child and adolescent populations. It also outlines special issues to consider when framing health promotion messages for children and adolescents. Finally, we explore the use of new and existing technologies as delivery mechanisms for education on vaccines and immunizations in populations of children and adolescents.

EXPERT COMMENTARY

Children undergo cognitive development and experiences with vaccines (e.g. pain or education) have the potential to create future attitudes toward vaccines. This can influence future vaccine behaviour, including their participation in decision-making around adolescent vaccines, their decisions to vaccinate themselves when they are adults, and their decisions to vaccinate their own children. Interventions aimed at children, such as education, can create positive attitudes toward vaccines. These can also potentially influence parental attitudes toward vaccines as children convey this knowledge to them. Both of these impacts require further study.

Adolescent values for immunisation programs in Australia: A discrete choice experiment

Objectives

The importance of adolescent engagement in health decisions and public health programs such as immunisation is becoming increasingly recognised. Understanding adolescent preferences and further identifying barriers and facilitators for immunisation acceptance is critical to the success of adolescent immunisation programs. This study applied a discrete choice experiment (DCE) to assess vaccination preferences in adolescents.

Methods

This study was conducted as a cross-sectional, national online survey in Australian adolescents. The DCE survey evaluated adolescent vaccination preferences. Six attributes were assessed including disease severity, target for protection, price, location of vaccination provision, potential side effects and vaccine delivery method. A mixed logit model was used to analyse DCE data.

Results

This survey was conducted between December 2014 and January 2015. Of 800 adolescents aged 15 to 19 years, stronger preferences were observed overall for: vaccination in the case of a life threatening illness (p<0.001), lower price vaccinations (p<0.001), mild but common side effects (p = 0.004), delivery via a skin patch (p<0.001) and being administered by a family practitioner (p<0.001). Participants suggested that they and their families would be willing to pay AU$394.28 (95%CI: AU$348.40 to AU$446.92) more for a vaccine targeting a life threatening illness than a mild-moderate illness, AU$37.94 (95%CI: AU$19.22 to AU$57.39) more for being vaccinated at a family practitioner clinic than a council immunisation clinic, AU$23.01 (95%CI: AU$7.12 to AU$39.24) more for common but mild and resolving side effects compared to rare but serious side effects, and AU$51.80 (95%CI: AU$30.42 to AU$73.70) more for delivery via a skin patch than injection.

Conclusions

Consideration of adolescent preferences may result in improved acceptance of, engagement in and uptake of immunisation programs targeted for this age group.

The next chapter for group B meningococcal vaccines

The majority of invasive meningococcal disease (IMD) in the developed world is caused by capsular group B Neisseria meningitidis, however success with vaccination against organisms bearing this capsule has previously been restricted to control of geographically limited clonal outbreaks. As we enter a new era, with the first routine program underway to control endemic group B meningococcal disease for infants in the UK, it is timely to review the key landmarks in group B vaccine development, and discuss the issues determining whether control of endemic group B disease will be achieved. Evidence of a reduction in carriage acquisition of invasive group B meningococcal strains, after vaccination among adolescents, is imperative if routine immunization is to drive population control of disease beyond those who are vaccinated (i.e. through herd immunity). The need for multiple doses to generate a sufficiently protective response and reactogenicity remain significant problems with the new generation of vaccines. Despite these limitations, early data from the UK indicate that new group B meningococcal vaccines have the potential to have a major impact on meningococcal disease, and to provide new insight into how we might do better in the future.

Vaccine preferences and acceptance of older adults

BACKGROUND

Expanding vaccination programs for the older population might be important as older adults are becoming a larger proportion of the general population. The aim of this study is to determine the relative importance of vaccine and disease specific characteristics and acceptance for Dutch older adults, including pneumococcal disease, herpes zoster, pertussis vaccination, and influenza vaccination.

METHODS

A discrete choice experiment was conducted to generate choice data that was analyzed using a mixed multinomial logit statistical model.

RESULTS

Important factors that were associated with vaccination acceptance in older adults are high mortality risk of the infectious disease, high susceptibility of getting the infectious disease, and high vaccine effectiveness. Age, influenza vaccination in 2013 and self-perceived health score were identified as personal factors that affect vaccine preference. Potential vaccination rates of older adults were estimated at 68.1% for pneumococcal vaccination, 58.1% for herpes zoster vaccination, 53.9% for pertussis vaccination and 54.3% for influenza vaccination. For persons aged 50-65, potential vaccination rates were estimated at 58.1% for pneumococcal vaccination, 49.5% for herpes zoster vaccination, 43.9% for pertussis vaccination and 42.2% for influenza vaccination. For persons aged 65 and older, these were respectively 76.2%, 67.5%, 57.5% and 65.5%.

DISCUSSION

Our results suggest that older adults are most likely to accept pneumococcal vaccination of the four vaccines. Information provision accompanied with the implementation of a new vaccine has to be tailored for the individual and the vaccine it concerns. Special attention is needed to ensure high uptake among persons aged 50-65years.

Adolescent confidence in immunisation: Assessing and comparing attitudes of adolescents and adults

INTRODUCTION

There is limited knowledge of adolescent views and attitudes towards immunisation. Our study investigated adolescent attitudes to immunisation and compared differences in vaccination attitudes between adolescents and adults.

METHODS

This study was a cross-sectional, national online survey. Recruitment was stratified by state and gender to ensure findings were nationally representative. Regression analyses were performed to assess and compare adolescent and adult views on vaccine benefits, community protection, risks, side effects, sources of information, and decision-making preference.

RESULTS

In 2013, 502 adolescents and 2003 adults completed the online survey. Lower levels of vaccine confidence were observed in adolescents with adolescents less likely to believe vaccines are beneficial and/or safe compared to adults (p=0.043). Compared to females, males were less confident of vaccine benefits (p<0.05) but less concern about vaccine side effects (p<0.05). Adolescents were more concerned about vaccine side effects than adults for pain (p<0.001), redness or swelling (p<0.001), and fever (p=0.006). Adolescents were less likely than adults to consider health professionals (p<0.001) and the media (e.g. internet) (p=0.010) as important sources of information, and were more likely to seek information from social networks (p<0.001) including families and schools. Although 62.0% of adolescents agreed that parents should make the decision about vaccination for them, adolescents were more likely to prefer a joint decision with parents (p<0.001) or by themselves (p=0.007) compared with adults.

CONCLUSION

Adolescents have a lesser understanding of vaccine safety and benefits than adults and have higher concerns about potential vaccine reactions. Improving adolescent awareness and knowledge of the benefits and risks of vaccination through school-based educational programs may improve confidence in and uptake of vaccines for adolescents and increase vaccine confidence in the next generation of parents.