Understanding influencing attributes of COVID-19 vaccine preference and willingness-to-pay among Chinese and American middle-aged and elderly adults: A discrete choice experiment and propensity score matching study.

Background and objective: COVID-19 has imposed burdens on public health systems globally. Owing to the urgency of vaccination, this study aimed at comparing the differences in preference and willingness to pay of COVID-19 vaccine among Chinese and American middle-aged and elderly adults. Methods: A cross-sectional survey containing demographic questions, rating their acceptance of COVID-19 vaccination with and without recommendations from friends, family members or employers (the social cues referred to in our study), and a discrete choice experiment understanding COVID-19 vaccine preference and willingness to pay was conducted to collect data. Propensity score matching was utilized to adjust confounding factors of baseline characteristics and the relative importance of respondents' preference for each attribute and its level was estimated using a conditional logit model. Then, willingness to pay was calculated. Results: In total, 3,494 (2,311 and 1,183 from China and the United States, respectively) completed the questionnaire, among which 3,444 questionnaires were effective. After propensity score matching, 1,604 respondents with 802 from the US and 802 from China were included. Under the influence of the social cues, Chinese respondents' vaccine acceptance decreased from 71.70 to 70.70%, while American respondents' vaccine acceptance increased from 74.69 to 75.81%. The discrete choice experiment showed that American respondents regarded the efficacy of COVID-19 vaccine as the most important attribute, whereas Chinese respondents attached the highest importance to the cost of vaccination. But overall, the COVID-19 vaccine with the higher efficacy, the milder adverse effect, the lower cost, and the longer duration will promote the preference of the public in both countries. Additionally, the public were willing to spend the most money for a reduction in COVID-19 vaccine adverse effect from moderate to very mild (37.476USD for the United States, 140.503USD for China), followed by paying for the 1% improvement in its efficacy and paying for the one-month extension of its duration. Conclusion: Given the impact of social cues on vaccine acceptance, Chinese government should promote reasonable vaccine-related information to improve national vaccination acceptance. Meanwhile, considering the influence of COVID-19 attributes on public preference and willingness to pay, regulating the vaccine pricing, improving the efficacy of the vaccine, reducing its adverse effect, and prolonging the duration of the vaccine works will contribute to vaccine uptake.

Impact of Media Use on Chinese Public Behavior towards Vaccination with the COVID-19 Vaccine: A Latent Profile Analysis.

(1) Background: research on vaccines has received extensive attention during epidemics. However, few studies have focused on the impact of media use on vaccination behavior and the factors influencing vaccination in groups with different media use degrees; (2) Method: Based on seven items related to media use, a total of 11,031 respondents were categorized by the frequency of media use by using latent profile analysis (LPA). Binary regression analysis was used to study the factors that influence the vaccination behaviors of people with different media use frequencies; (3) Results: All respondents were classified into the following three groups: media use low frequency (9.7%), media use general (67.1%), and media use high frequency (23.2%). Media use low frequency (ß = -0.608, p < 0.001) was negatively associated with COVID-19 vaccination behavior. In the media use low frequency, analysis showed that "aged 41 years or older" ß = 1.784, p < 0.001), had religious belief (ß = 0.075, p < 0.05), were ethnic minorities (ß = 0.936, p < 0.01) and had friends support (ß = 0.923, p < 0.05) were associated with a preference to accept the COVID-19 vaccine. In the media use general, those who aged 41 years old and older (ß = 1.682, p < 0.001), had major depression (ß = 0.951, p < 0.05), had friends support (ß = 0.048, p < 0.001) would be more likely to receive COVID-19 vaccination. However, respondents who live in towns (ß = -0.300, p < 0.01) had lower behaviors to receive vaccination for COVID-19. In the media use high frequency, the respondents who aged 41 or older (ß = 1.010, p < 0.001), were ethnic minorities (ß = 0.741, p < 0.001), had moderate depression (ß = 1.003, p < 0.05) would receive the vaccination for COVID-19 positively; (4) Conclusions: The more occluded the media use is, the less likely the respondents are to get vaccinated against COVID-19. Vaccination behavior is influenced by different factors in groups with different frequencies of media use. Therefore, the government and appropriate departments should make individualized and targeted strategies about COVID-19 vaccination and disseminate the vaccination information to different media use groups.

Personality Effects on Chinese Public Preference for the COVID-19 Vaccination: Discrete Choice Experiment and Latent Profile Analysis Study.

Objective: This study aims to investigate the differences in public vaccination preference for the COVID-19 vaccine with different personality characteristics. Methods: Based on the Big Five Personality Inventory (BFI-10), a total of 1200 respondents were categorized by personality characteristics using Latent Profile Analysis (LPA). The preference of members the public with different personality characteristics for COVID-19 vaccination was investigated based on a discrete choice experiment (DCE). Results: All respondents were divided into three groups, named the General and Stable type (79.67%), Conscientious and Agreeable type (9.5%), and Open and Extroverted type (10.83%). For the percentage importance of vaccine attributes, both the General and Stable type and Conscientious and Agreeable type respondents considered cost to be the most important (41.93% and 34.95% respectively). However, the Open and Extroverted type respondents considered efficacy as the most important (31.05%). In our conditional logit model (CLOGIT), for vaccine adverse effects, the General and Stable type and Conscientious and Agreeable type respondents preferred "very mild", while the Open and Extroverted type preferred "mild" (OR:1.108, 95%CI 0.977-1.256). The Open and Extroverted type had a higher willingness to pay (WTP) for the most preferred vaccine level compared to the other types. Conclusions: The Open and Extroverted respondents have the highest willingness to vaccinate. The General and Stable type and Conscientious and Agreeable respondents think that the cost of the vaccine is the most important attribute, and prefer the mildest side effects. The Open and Extroverted type think that vaccine efficacy is the most important attribute, prefer "mild" side effects, and have higher willingness to pay for their favorite vaccine level.