Gender differences in the determinants of willingness to get the COVID-19 vaccine among the working-age population in Japan

COVID-19; employees; infection; occupational health; SARS-CoV-2; 56 vaccine; working age 57 58 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 3

59 Vaccines are expected to be a key measure against the coronavirus disease 2019 60 (COVID-19) pandemic.1 Vaccine development usually takes decades, and, although a 61 variety of COVID-19 vaccines are currently being developed at an unprecedented rate, 62 evidence has not yet established their long-term safety. 2 In Japan, the COVID-19 63 vaccination program has been administered since February 2021, with eligibility 64 proceeding in the following order: healthcare workers, older adults (aged 65 years or 65 older), and people with underlying diseases and caregivers working at care facilities for 66 older adults.3 Other people will become eligible for vaccination at a later date, following 67 the populations listed above, which are the main sources of infection. 4 To reach herd 68 immunity, most citizens need to be vaccinated.5 69 70 Vaccination intentions are recognized as the most important issue in the rollout of 71 vaccination programs.6 However, Japan is known for its lack of public trust in vaccines7 72 because negative campaigns against the vaccination—highlighting scandals and severe 73 adverse effects, for instance—have increased hesitation concerning some vaccinations 74 over the past several decades. 8-11 For example, a national human papillomavirus 75 vaccination program for girls was launched in 2013 but was discontinued after 3 months 76 because of sensational case reports of adverse effects. 12 This event had a negative 77 impact on vaccination intentions, especially among women.13 78 79 Various factors are related to COVID-19 vaccination intentions. Previous studies have 80 reported that age, gender, race, education level, influenza vaccination status, and fear of 81 COVID-19 transmission are associated with the willingness to get the COVID-19 82 vaccine.14-18 In Japan, willingness to get the COVID-19 vaccine was previously 83 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 4 examined in a single study of 1,100 adults, with results showing that vaccine hesitancy 84 was higher in Japan than in other countries, particularly among women. 19 However, 85 gender differences in the determinants of willingness to get the COVID-19 vaccine, 86 such as demographic and health characteristics, influenza vaccination status, and fear of 87 COVID-19 transmission, have not been fully investigated. Furthermore, more studies 88 involving larger samples of the working-age population are needed. Therefore, the 89 current study examined gender differences in the determinants of willingness to get the 90 COVID-19 vaccine among the working-age population in Japan. This study will give 91 important insight into identifying target groups in need of intervention regarding 92 COVID-19 vaccination. 93 94

95 Study design 96 We conducted a cross-sectional study about COVID-19 among the working-age 97 population in Japan on December 22–26, 2020. The present article is part of a series of 98 studies conducted under the CORoNaWork (Collaborative Online Research on the 99 Novel-coronavirus and Work) Project. 20 This study was conducted during the third 100 wave of the COVID-19 pandemic in Japan, when the number of infected people and 101 deaths peaked. 21 Although COVID-19 vaccination began in December 2020 in the 102 United Kingdom (UK) and the United States (US), Japan had not yet begun to 103 administer COVID-19 vaccines during the survey period.22 Pfizer requested a fast-track 104 approval of its COVID-19 vaccine from the government of Japan on December 18, 105 2020 and became the first company to receive this approval on February 14, 2021.3 106 107 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 5 Criteria for eligibility for the present study were being aged 20–65 years and currently 108 working. Healthcare workers and caregivers were not invited to participate. We 109 recruited study participants from the panelists of Cross Marketing Inc. (Tokyo, Japan), 110 an Internet research company. These panelists regularly respond to self-administered 111 Internet surveys distributed by the company, receiving tokens that can be redeemed for 112 products and services as compensation. 113 114 For this survey, we used quota sampling by gender, residence (five districts), and 115 occupation (office worker or other). Information on these characteristics was retrieved 116 from the panelists’ Cross Marketing Inc. registration information. Cross Marketing Inc. 117 sent an invitation email to panelists who met the eligibility criteria, and those who were 118 interested in the study proceeded to the survey via a hyperlink. The participants 119 provided informed consent prior to beginning the online questionnaire. We set a quota 120 of 1,650 participants for each of the 20 strata and ceased recruitment when the target 121 number was reached. In total, 33,087 participants from all over Japan completed the 122 questionnaire. After excluding invalid responses, a total of 27,036 participants 123 remained. All participants received standard incentives through Cross Marketing Inc. 124 (i.e., a few dollars’ worth of tokens). The study was conducted according to the 125 guidelines of the Declaration of Helsinki, and it was approved by the Ethics Committee 126 of the University of Occupational and Environmental Health, Japan (Approval number: 127 R2-079). 128 129 Measures 130 The survey questions included items on demographic and health characteristics, 131 influenza vaccination status during the current season, fear of COVID-19 transmission, 132 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 6 and willingness to get the COVID-19 vaccine. The demographic and health 133 characteristics were gender, age, education, marital status, annual household income (1 134 USD was equal to 106.78 JPY, using 2020 conversion rates), 23 underlying disease, and 135 smoking status. In line with a previous study, 18 we developed the following item to 136 assess willingness to get the COVID-19 vaccine: “If a COVID-19 vaccine becomes 137 available, I will get it.” The possible answers to this question were yes and no. Fear of 138 COVID-19 transmission was assessed by asking “Do you fear COVID-19 139 transmission?”, with yes and no as the possible responses. 140 141 Data analysis 142 We calculated frequencies and proportions for all variables. Descriptive statistics were 143 also calculated by gender to reveal more detailed background factors. Logistic 144 regression analysis was performed to calculate adjusted odds ratios (aORs) and 95% 145 confidence intervals (CIs) for all variables to evaluate associations with willingness to 146 get the COVID-19 vaccine. Because we hypothesized that gender was an important 147 determinant in the current study, the analysis was stratified by gender. We adjusted for 148 age; no adjustments were made for the other covariates because the purpose of this 149 study was to detect target populations for future intervention programs. All P-values 150 were two-sided, and statistical significance was set at P < .05. We used Stata/SE 16.1 151 (StataCorp, College Station, TX, USA) for all analyses. 152 153

154 Table 1 shows the characteristics of the study population. Data on a total of 27,036 155 participants (13,814 men and 13,222 women) were analyzed. We found that 43.0% of 156 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 7 the participants reported that they had received the influenza vaccine during the current 157 season. Regarding fear of COVID-19 transmission, 74.0% indicated that they felt fear. 158 Overall, 37.5% of the participants expressed that they would like to get a COVID-19 159 vaccine if it becomes available. 160 161 Table 2 displays the characteristics of the study population by willingness to get the 162 COVID-19 vaccine and gender. A total of 5,780 men (41.8%) and 4,367 women 163 (33.0%) were willing to get the COVID-19 vaccine. Relatively high percentages of 164 participants were willing to get the COVID-19 vaccine among those aged 60–65 years 165 (men: 48.0%; women: 41.1%), those who had an underlying disease (men: 47.8%; 166 women: 37.0%), those who felt fear of COVID-19 transmission (men: 49.5%; women: 167 37.0%), and those who had received the influenza vaccine during the current season 168 (men: 59.2%; women: 43.7%). These percentages were higher in men than in women. 169 170 Table 3 presents the factors associated with willingness to get the COVID-19 vaccine by 171 gender. Men aged 50–59 years (aOR: 1.38; 95% CI: 1.02–1.86) and those aged 60–65 172 years (aOR: 1.76; 95% CI: 1.30–2.40) were more willing to get the COVID-19 vaccine 173 than were men aged 20–29 years. Conversely, women aged 30–39 years (aOR: 0.86; 174 95% CI: 0.76–0.97) and those aged 40–49 years (aOR: 0.80; 95% CI: 0.71–0.91) were 175 less willing to get the vaccine than were women aged 20–29 years. Regarding education 176 level, compared with having a junior high or high school education, having a university 177 or graduate school education was a facilitating factor for willingness to get the COVID-178 19 vaccine for men (aOR: 1.13; 95% CI: 1.04–1.22) but a barrier for women (aOR: 179 0.83; 95% CI: 0.75–0.91). 180 181 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 8 For both men and women, a significantly higher likelihood of willingness to get the 182 COVID-19 vaccine was observed among those who were married (men—aOR: 1.37; 183 95% CI: 1.26–1.49; women—aOR: 1.30; 95% CI: 1.20–1.40), those with a higher 184 annual household income (men—aOR: 1.91; 95% CI: 1.61–2.26; women—aOR: 1.32; 185 95% CI: 1.13–1.53), those with an underlying disease (men—aOR: 1.43; 95% CI: 1.34–186 1.54; women—aOR: 1.29; 95% CI: 1.19–1.39), those who currently smoked (men—187 aOR: 1.20; 95% CI: 1.11–1.30; women—aOR: 1.36; 95% CI: 1.24–1.51), those who 188 had been vaccinated against influenza during the current season (men—aOR: 3.28; 95% 189 CI: 3.05–3.52; women—aOR: 2.53; 95% CI: 2.35–2.73), and those with a fear of 190 COVID-19 transmission (men—aOR: 3.09; 95% CI: 2.85–3.35; women—aOR: 2.54; 191 95% CI: 2.29–2.81). 192 193

194 This study provides evidence on gender differences in the determinants of willingness 195 to get the COVID-19 vaccine. In the present study, the percentage of people who were 196 willing to get the COVID-19 vaccine was lower among women than among men 197 (33.0% vs. 41.8%). This trend was similar to the findings of previous studies in 198 developed countries.14, 19, 24, 25 Notably, we found a gender gap in the associations of age 199 and education level with willingness to get the COVID-19 vaccine: men who were older 200 or had a higher level of education were more willing to get the vaccine, whereas women 201 aged 30–49 years and those with a higher level of education were less willing to get the 202 vaccine. Other factors showed similar trends for men and women: for both men and 203 women, a higher likelihood of being willing to get the COVID-19 vaccine was observed 204 in married participants, those with a higher annual household income, those who had an 205 underlying disease, those who currently smoked, those who had been vaccinated against 206 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 9 influenza during the current season, and those with a fear of COVID-19 transmission. 207 These findings give important insight into identifying target groups for improving 208 COVID-19 vaccination intentions, especially among women. 209 210 The most notable finding of the present study was a gender gap in the associations of 211 age and education with willingness to get the COVID-19 vaccine. As mentioned above, 212 men who were older or had a higher level of education were more willing to get the 213 vaccine, whereas women aged 30–49 years and those with a higher level of education 214 were less willing to get the vaccine. For men, this finding is consistent with previous 215 studies; older age and higher level of education are known facilitators for health 216 protection, which should correlate with COVID-19 vaccination intentions. 24, 26, 27 217 Conversely, the current results for women vary from the findings presented in these 218 studies. This difference may be explained by a higher level of concern about adverse 219 effects of the vaccine among women aged 30–49 years and among those with a 220 relatively high level of education in Japan during the current study period. We 221 considered that recent reporting on adverse effects following receipt of the human 222 papillomavirus vaccine in major Japanese newspapers may have had a negative impact 223 on the vaccination intentions of these groups. 28 These findings may imply the need for 224 intervention in this population regarding COVID-19 vaccination. 225 226 The current study found that influenza vaccination status and fear of COVID-19 227 transmission were strongly associated with willingness to get the COVID-19 vaccine 228 among both men and women. These results are in line with previous studies.16, 17, 29, 30 In 229 the case of the 2009 influenza pandemic, perceived risk of infection translated into 230 preventive behaviors, including vaccination. 31 Similarly, the experience of receiving a 231 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 10 vaccine have been shown to increase an individual’s confidence in the efficacy and 232 safety of other vaccines. 29, 30 Nevertheless, working-age people have fewer 233 opportunities to receive the influenza vaccine compared with older adults because of the 234 former group’s busy work schedules.32 These findings suggest that providing education 235 about COVID-19 and influenza vaccination in the workplace may be an effective 236 strategy to increase COVID-19 vaccine uptake. 237 238 In the current study, a higher likelihood of being willing to get the COVID-19 vaccine 239 was observed among those who were married, those with a higher annual household 240 income, those with an underlying disease, and those who currently smoked. Vulnerable 241 populations, such as people with low socioeconomic status, are often found to have 242 relatively poor health and to need support regarding their willingness to be vaccinated.16 243 In addition, a previous study on influenza vaccination suggests that single people are 244 less willing to be vaccinated compared with their married counterparts because single 245 people are not at risk of transmission from coresident family members. 11 Our finding 246 regarding the presence of underlying disease may be related to the fear of COVID-19 247 transmission because underlying disease a known risk factor for clinical severity of 248 COVID-19 infection.24 Only our finding on tobacco use was inconsistent with previous 249 studies, which have found that smokers often tend to refuse vaccines regardless of the 250 risk of clinical worsening associated with smoking. 10, 11, 33 Further studies should focus 251 on confirming the relationship between smoking and COVID-19 vaccination intention. 252 253 Overall, we found that 37.5% of the working-age population in Japan was willing to get 254 the COVID-19 vaccine. This percentage is not high enough to achieve herd immunity 255 through the vaccination program. 5 This acceptance rate is lower than that in other 256 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 11 countries, such as China (91.3%), France (58.9%), the US (56.9%), and Russia 257 (54.9%).6 Furthermore, the acceptance rate is lower than the rate reported in a previous 258 study in Japan (65.7%) that was conducted in September 2020. 19 One possible reason 259 for the low vaccination intention in the current study may be tied to the research 260 period.15 Our study was conducted in December 2020, right after the start of the 261 COVID-19 vaccination program in the UK and the US, and the media coverage of 262 adverse effects was exaggerated.34, 35 Another reason is that people of working age have 263 been found to be less willing to get the COVID-19 vaccine compared with older 264 adults,19 which would affect the present results. These findings have important 265 implications for vaccination intentions, although vaccination acceptance may change 266 after the vaccine is available for administration among the working-age population. 267 268 The main strengths of this study are the large sample size and the use of a sample from 269 throughout Japan. A limitation of this study is that we recruited study participants from 270 an Internet research company’s list of panelists. A previous study on the anti-vaccine 271 movement reported that anti-vaccine messages were more prevalent on the Internet than 272 in other sources. 36 Therefore, the participants in the current study may have been 273 particularly likely to access anti-vaccine websites, and this should be taken into account 274 when interpreting the results of our study. Additionally, we conducted the current study 275 before the administration of the COVID-19 vaccination program in Japan; therefore, we 276 could not provide participants with detailed information, such as the vaccination 277 schedule, which may have affected their willingness to get the vaccine. 278 279 In conclusion, the current study revealed a gender gap in the associations of age and 280 education level with willingness to get the COVID-19 vaccine. In particular, women 281 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 12 aged 30–49 years and those with a higher level of education were less willing to get the 282 vaccine. These findings may imply the need for intervention for this population 283 regarding COVID-19 vaccination. Providing education about COVID-19 and influenza 284 vaccination in the workplace may be an effective strategy to increase COVID-19 285 vaccine uptake. 286 287 Acknowledgments 288 We thank the current members of the CORoNaWork Project (listed in alphabetical 289 order): Professor Yoshihisa Fujino (present chairperson of the study group), Dr. Hajime 290 Ando, Professor Hisashi Eguchi, Dr. Kazunori Ikegami, Dr. Tomohiro Ishimaru, Dr. 291 Arisa Harada, Dr. Ayako Hino, Dr. Kyoko Kitagawa, Dr. Kosuke Mafune, Professor 292 Shinya Matsuda, Dr. Ryutaro Matsugaki, Professor Koji Mori, Dr. Keiji Muramatsu, 293 Dr. Masako Nagata, Dr. Tomohisa Nagata, Ms. Ning Liu, Professor Akira Ogami, Dr. 294 Rie Tanaka, Dr. Seiishiro Tateishi, Dr. Kei Tokutsu and Professor Mayumi Tsuji. All 295 members are affiliated with the University of Occupational and Environmental Health, 296 Japan. 297 298 Funding details 299 This study was supported and partly funded by the University of Occupational and 300 Environmental Health, Japan; General Incorporated Foundation (Anshin Zaidan); The 301 Development of Educational Materials on Mental Health Measures for Managers at 302 Small-sized Enterprises; Health, Labour and Welfare Sciences Research Grants: 303 Comprehensive Research for Women’s Healthcare (H30-josei-ippan-002) and Research 304 for the Establishment of an Occupational Health System in Times of Disaster (H30-305 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 13 roudou-ippan-007); scholarship donations from Chugai Pharmaceutical Co., Ltd.; the 306 Collabo-Health Study Group; and Hitachi Systems, Ltd. 307 308 Disclosure statement 309 The authors declare no conflict of interest. 310 311

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CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 16 Table 1. Characteristics of the study population. 435 n (%) Gender Men 13,814 (51.1) Women 13,222 (48.9) Age (years) 20–29 1,905 (7.0) 30–39 4,858 (18.0) 40–49 8,011 (29.6) 50–59 9,012 (33.3) 60–65 3,250 (12.0) Education level Junior high or high school 7,321 (27.1) Vocational school or college 6,544 (24.2) University or graduate school 13,171 (48.7) Marital status Single 9,164 (33.9) Divorced or widowed 2,843 (10.5) Married 15,029 (55.6) Annual household income (JPY) < 2,000,000 1,709 (6.3) 2,000,000–3,999,999 5,548 (20.5) 4,000,000–7,999,999 11,927 (44.1) ≥ 8,000,000 7,852 (29.1) Underlying disease No 17,526 (64.8) Yes 9,510 (35.2) Smoking status Never smoked 14,587 (54.0) Former smoker 5,445 (20.1) Current smoker 7,004 (25.9) Received the influenza vaccine during the current season No 15,411 (57.0) Yes 11,625 (43.0) Fear of COVID-19 transmission No 7,019 (26.0) Yes 20,017 (74.0) Willing to get the COVID-19 vaccine No 16,889 (62.5) Yes 10,147 (37.5) JPY: Japanese yen; COVID-19: coronavirus disease 2019 436 437 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 17 Table 2. Characteristics of the study population by willingness to get the COVID-19 438 vaccine and gender. 439 Men Women Willing Unwilling Willing Unwilling n = 5,780 (41.8%) n = 8,034 (58.2%) n = 4,367 (33.0%) n = 8,855 (67.0%) n (%) n (%) n (%) n (%) Age (years) 20–29 66 (34.4) 126 (65.6) 604 (35.3) 1,109 (64.7) 30–39 424 (37.8) 698 (62.2) 1,192 (31.9) 2,544 (68.1) 40–49 1,487 (39.1) 2,316 (60.9) 1,282 (30.5) 2,926 (69.5) 50–59 2,540 (41.9) 3,527 (58.1) 1,034 (35.1) 1,911 (64.9) 60–65 1,263 (48.0) 1,367 (52.0) 255 (41.1) 365 (58.9) Education level Junior high or high school 1,562 (40.1) 2,335 (59.9) 1,212 (35.4) 2,212 (64.6) Vocational school or college 818 (40.7) 1,194 (59.3) 1,523 (33.6) 3,009 (66.4) University or graduate school 3,400 (43.0) 4,505 (57.0) 1,632 (31.0) 3,634 (69.0) Marital status Single 1,195 (35.3) 2,189 (64.7) 1,724 (29.8) 4,056 (70.2) Divorced or widowed 391 (39.9) 590 (60.1) 663 (35.6) 1,199 (64.4) Married 4,194 (44.4) 5,255 (55.6) 1,980 (35.5) 3,600 (64.5) Annual household income (JPY) < 2,000,000 219 (31.1) 486 (68.9) 289 (28.8) 715 (71.2) 2,000,000–3,999,999 897 (38.8) 1,414 (61.2) 1,056 (32.6) 2,181 (67.4) 4,000,000–7,999,999 2,585 (41.2) 3,694 (58.8) 1,866 (33.0) 3,782 (67.0) ≥ 8,000,000 2,079 (46.0) 2,440 (54.0) 1,156 (34.7) 2,177 (65.3) Underlying disease No 3,201 (38.0) 5,221 (62.0) 2,844 (31.2) 6,260 (68.8) Yes 2,579 (47.8) 2,813 (52.2) 1,523 (37.0) 2,595 (63.0) Smoking status Never smoked 1,999 (38.4) 3,213 (61.6) 2,976 (31.7) 6,399 (68.3) Former smoker 1,664 (44.4) 2,083 (55.6) 554 (32.6) 1,144 (67.4) Current smoker 2,117 (43.6) 2,738 (56.4) 837 (38.9) 1,312 (61.1) Received the influenza vaccine during the current season No 2,570 (30.6) 5,825 (69.4) 1,656 (23.6) 5,360 (76.4) Yes 3,210 (59.2) 2,209 (40.8) 2,711 (43.7) 3,495 (56.3) Fear of COVID-19 transmission No 986 (23.9) 3,146 (76.1) 542 (18.8) 2,345 (81.2) Yes 4,794 (49.5) 4,888 (50.5) 3,825 (37.0) 6,510 (63.0) COVID-19: coronavirus disease 2019; JPY: Japanese yen 440 441 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint 18 Table 3. Factors associated with willingness to get the COVID-19 vaccine by gender. 442 Men Women aORa (95% CI) P-value aORa (95% CI) P-value Age (years) 20–29 1.00 - - 1.00 - - 30–39 1.16 (0.84–1.60) .366 0.86 (0.76–0.97) .015 40–49 1.23 (0.90–1.66) .191 0.80 (0.71–0.91) < .001 50–59 1.38 (1.02–1.86) .039 0.99 (0.88–1.13) .918 60–65 1.76 (1.30–2.40) < .001 1.28 (1.06–1.55) .010 Education level Junior high or high school 1.00 - - 1.00 - - Vocational school or college 1.04 (0.93–1.16) .461 0.93 (0.84–1.02) .099 University or graduate school 1.13 (1.04–1.22) .003 0.83 (0.75–0.91) < .001 Marital status Single 1.00 - - 1.00 - - Divorced or widowed 1.13 (0.97–1.31) < .001 1.30 (1.16–1.46) < .001 Married 1.37 (1.26–1.49) < .001 1.30 (1.20–1.40) < .001 Annual household income (JPY) < 2,000,000 1.00 - - 1.00 - - 2,000,000–3,999,999 1.45 (1.21–1.73) < .001 1.20 (1.03–1.41) .020 4,000,000–7,999,999 1.61 (1.36–1.90) < .001 1.23 (1.06–1.42) .007 ≥ 8,000,000 1.91 (1.61–2.26) < .001 1.32 (1.13–1.53) < .001 Underlying disease No 1.00 - - 1.00 - - Yes 1.43 (1.34–1.54) < .001 1.29 (1.19–1.39) < .001 Smoking status Never smoked 1.00 - - 1.00 - - Former smoker 1.21 (1.11–1.33) < .001 1.04 (0.93–1.16) .521 Current smoker 1.20 (1.11–1.30) < .001 1.36 (1.24–1.51) < .001 Received the influenza vaccine during the current season No 1.00 - - 1.00 - - Yes 3.28 (3.05–3.52) < .001 2.53 (2.35–2.73) < .001 Fear of COVID-19 transmission No 1.00 - - 1.00 - - Yes 3.09 (2.85–3.35) < .001 2.54 (2.29–2.81) < .001 COVID-19: coronavirus disease 2019; aOR: adjusted odds ratio; CI: confidence 443 interval; JPY: Japanese yen 444 aAdjusted for age 445 446 . CC-BY-NC-ND 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 20, 2021. ; https://doi.org/10.1101/2021.04.13.21255442doi: medRxiv preprint