key: cord-0690751-cwtodi4w
authors: Suzuki, Naho; Yamamoto, Tetsuya; Uchiumi, Chigusa; Sugaya, Nagisa
title: Socio-economic and behavioral characteristics associated with COVID-19 vaccine hesitancy under a declared state of emergency in Japan
date: 2022-03-23
journal: Brain Behav Immun Health
DOI: 10.1016/j.bbih.2022.100448
sha: 53aff43748f7b2dc312c0fbdc2f59a49686c195f
doc_id: 690751
cord_uid: cwtodi4w

Evidence regarding coronavirus disease 2019 vaccination indicates that some people hesitate to be vaccinated, and previous studies demonstrate the variables that influence hesitancy to vaccinate. However, they have not limited the target population to areas where infection is prominent. This study aimed to clarify the characteristics of people living in these areas who hesitate to be vaccinated and recommend effective approaches to encourage vaccination. The survey was conducted online between February 24 and March 1, 2021, during which the 2nd state of emergency was declared in Japan. The analytic sample comprised 17,582 unvaccinated individuals (mean age = 48.6 ± 13.8, range = 18–90 years). The t-test results indicate that current or past treatment for physical illness exerted a strong influence on vaccine hesitancy (ds = 0.30). Similarly, multiple regression analyses revealed that understanding the importance and necessity for preventive behaviors had the greatest influence on the intention to vaccinate (β = 0.48). Regarding recommendations to promote willingness to be vaccinated, our findings indicated that clear explanation of the reasons for the necessity for these behaviors and collaboration between representatives of various communities would effectively encourage vaccination.

Coronavirus disease 2019 (COVID-19) vaccination has been promoted in many countries, and socioeconomic and 34 behavioral variables have been reported to influence public hesitation to vaccinate. Previous studies revealed that 35 women (Edwards et al., 2021) , young people (Schwarzinger et al., 2021) , and those with low trust in the government 36 (Murphy et al., 2021) tend to hesitate to be vaccinated. 37

The infection rate of COVID-19 varies widely among regions, and it is particularly important promote vaccination 38 in areas with severe outbreak. Hence, it is necessary to examine the intention to be vaccinated and the characteristics 39 that influence this among people living in such areas. However, few studies have identified the factors specific to the 40 areas with severe outbreaks, how people living in these areas feel about getting vaccinated and the factors that 41 influence them. 42 Therefore, focusing on people living in areas where the outbreak was severe and who were covered by the declared 43 state of emergency, this study aimed to clarify the characteristics of people who hesitate to be vaccinated and to 44 recommend effective approaches to encourage vaccination based on those characteristics. 45 46 2. Methods 47 conducted online between February 24 and March 1, 2021, during which the 2 nd state of emergency was declared in 50 Japan. Participants were recruited from ten prefectures covered by the 2 nd state of emergency in Japan. The exclusion 51 criteria were as follows: age < 18 years, high school students, and residents living outside the ten prefectures. 52

Data were collected on an online platform (Macromill, Inc., Tokyo, Japan). All participants voluntarily responded 53 to the anonymous survey and provided informed consent. These data are the same as those collected by Yamamoto 54 

A previous study reported that decisions about whether to get vaccinated or not are influenced by altruism (Shim et 70 al., 2012) ; thus, that the impact of altruism must be considered. Information was collected on whether the participants 71 continued preventive behaviors (e.g., wearing a mask, washing their hands, refraining from going out) (Continuous 72 prevention), whether they took preventive behaviors altruistically to prevent infection of family members and others 73 (Altruistic), whether they took preventive behaviors to avoid social criticism and pressure (Prevention to avoid social 74 criticism and pressure), and whether they understood the importance and necessity for preventive behaviors 75 (Importance of prevention). Each item was assessed using a seven-point scale (1 = completely disagree, 4 = neither 76 agree nor disagree, 7 = completely agree). All the scales used in this survey, including this scale, were developed in 77 conjunction with the implementation of this survey. 78 79

The intentions to be vaccinated varies depending upon the source of information regarding COVID-19 (Murphy et 81 al., 2021); so that variable was also included. Information was collected on whether participants trusted COVID-19 82 related information from the government (Confident in COVID-19 information from the government) and whether 83 they trusted COVID-19 related information from social media (e.g., Twitter, Facebook) (Confident in COVID-19 84 information on social media). Each item was assessed using a seven-point scale (1 = completely disagree, 4 = neither

Participants' intention to be vaccinated (Vaccination intent) was assessed using a seven-point scale (1 = no intention, 89 4 = neither intend nor do not intend, 7 = fully intend). 90 91

We calculated the percentage of those who were already vaccinated, the overall mean intent to vaccinate, and the 93 percentage of intention to / or not to vaccinate. Data for those who were already vaccinated were excluded from 94 subsequent analyses. We conducted t-tests to examine whether sociodemographic variables differed between 95 intentions to vaccinate. Tukey's test was conducted to examine whether the degree of intention to vaccinate varied 96 according to household income. Multiple regression analyses were performed with vaccination intent as the objective 97 variable, age, and six prevention variables (Variables associated with the prevention of COVID-19) and information 98 variables (Trust in COVID-19 information sources) as exploratory variables. Additionally, we conducted power 99 analyses for t-tests and multiple regression analyses. If the power < 0.8, the possibility of committing a type II error 100

increases (Cohen, 1992) . 101

For all tests, significance was set at α = 0.05, two-tailed. RStudio version 3.6.0 was used to perform analyses. 102

The overall mean of the score for intention to vaccinate was 4.37 (SD = 1.86): the number of participants who 107 answered "completely disagree (1)" to "somewhat disagree (3)" was 4,501 (25.2%), "neither agree nor disagree (4)" 108 was 5,067 (28.4%), and "somewhat agree (5)" to "completely agree (7)" was 8,284 (46.4%). Result of the power 109 analyses indicated that sex (power = 0.99), marital status, presence of children, being a health care worker, currently 110 receiving treatment for severe physical diseases, and previous treatment for severe physical diseases (powers = 1) 111 displayed powers > 0.8, while current treatment for severe psychological illness (power = 0.06) and previous 112 treatment for severe psychological illness (power = 0.52) were < 0.8. 113

Descriptive statistics and t-test results are presented in Table 1 . Being female, unmarried, childless, a non-healthcare 114 worker, not receiving treatment for physical illness currently or in the past, and not receiving treatment for a 115 psychological illness in the past were significantly associated with lower intentions to vaccinate (p < 0.05). The 

Participants with an annual household income lower than 2 million yen had significantly lower intention to vaccinate 125 than those from other income categories, with the largest difference being between the group with an annual 126 household income of more than 20 million yen (< 2.0 million: M = 3.99; > 20.0 million: M = 4.80; p < 0.001). 127

The results of the multiple regression analyses are shown in Table 2 In this study, we clarified the socio-demographic, prevention, and information variables associated with the 142 hesitation to be vaccinated in areas and periods of severe COVID-19 spread under a declared state of emergency. 143

Analysis of intention to vaccinate revealed that more than half of the participants were either hesitant or uninterested 144 in getting vaccinated. This study was conducted in late February to early March 2021, immediately after the date 145 (February 17, 2021) when vaccination was initiated in Japan. Our findings indicate that in areas with ongoing spread 146 of COVID-19, many people were hesitate to receive vaccination at the start of COVID-19 vaccination in Japan. 147

Participants who were female, unmarried, childless, non-healthcare workers, not receiving treatment for physical 148 illness currently or in the past, and who had not received treatment for a psychological illness in the past were less 149 likely to be willing to receive the vaccination. Among these factors, the effect size for variables related to current or 150 past treatment for physical illness was the largest. Similarly, previous research indicates that being free of chronic 151 diseases was significantly associated with hesitation or refusal to vaccinate (Schwarzinger et al., 2021) . Our results 152 are also consistent with previous evidence (Edwards et al., 2021 ) that vaccination rated are lower for women than 153 men. However, it should be noted that the effect size for sex was small in this study. This may be related to the timing 154 of the survey. Side effects have been identified as one reason women hesitate to be vaccinated (Yoda et al., 2021; 155 Kadoya et al., 2021) . However, vaccination had just begun in Japan when this study was conducted. Therefore, the 156 side effects were not widely recognized, which may explain the relatively small effect size for sex in this study. that economic disparity also affects vaccination intentions. However, household income is affected by other factors 161 such as family forms, hence, future studies should take these factors into account and examine the influence of 162 economic status on intention to vaccinate. 163

Multiple regression analyses revealed that lower age, distrust of COVID-19 related information from the 164 government, distrust of COVID-19 related information on social media, and not understanding the importance and 165 the necessity for preventive behaviors were variables that significantly predicted lower intentions to vaccinate. In There are some limitations to this study. As mentioned above, this study used some of the data from Yamamoto et 172 al. (2021) , and because scales used in Yamamoto et al. (2021) were limited to those focused on mental health, we 173 were unable to evaluate the impact of all risk factors, such as perceived risk of COVID-19, fear of COVID-19, and 174 comorbid conditions. Additionally, we used scales that have not been examine reliability and validity in this study. In 175 future studies, we must use established scales and examine their reliability and validity. 176

Despite these limitations, given the results of this survey, we can provide suggestions for effective promotion of 177 vaccination. First, the group we recommend for target includes individuals who have never been treated for physical 178 promoting vaccination to a wide range of people, as in the past, focusing on certain people, such as those mentioned 180 above, would assist in increasing vaccination rates. Moreover, understanding the importance and necessity for 181 preventive behaviors had the strongest effect on intention to vaccinate. Therefore, in addition to encouraging 182 preventive behaviors, clearly explaining why these behaviors are necessary would effectively encourage vaccination 183 as a preventive behavior. However, our results also indicate that trust in the information provided by the government 184 is a variable that influences intention to vaccinate. Thus, that collaborative efforts between representatives of various 185 communities with the government to disseminate vaccine information may be more effective than information 186 provided by only the government. This is the first study to examine vaccine hesitancy among residents of areas under 187 a declared state of emergency in Japan. The results indicate that risk and protective factors must be taken into account 188 in our efforts to promote vaccination. Further, the suggestions mentioned above may be useful for policy makers. 189

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The authors declare no competing interests.