Table 3.
Age and sex adjusted odds ratio (OR) of vaccine hesitancy according to vaccine confidence and literacy by phase.
| January | June | September | |||||||
|---|---|---|---|---|---|---|---|---|---|
| AOR | 95% CI | p Value | AOR | 95% CI | p Value | AOR | 95% CI | p Value | |
| Vaccine confidence and literacy | |||||||||
| Vaccines are important for my health | 0.31 | 0.28–0.33 | <0.001 | 0.57 | 0.53–0.61 | <0.001 | 0.34 | 0.31–0.37 | <0.001 |
| Vaccines are effective | 0.37 | 0.34–0.41 | <0.001 | 0.59 | 0.55–0.64 | <0.001 | 0.36 | 0.33–0.39 | <0.001 |
| Vaccines are safe | 0.36 | 0.33–0.39 | <0.001 | 0.73 | 0.69–0.77 | <0.001 | 0.41 | 0.38–0.44 | <0.001 |
| My vaccination is important for the health of others in my community | 0.69 | 0.55–0.63 | <0.001 | 0.71 | 0.69–0.76 | <0.001 | 0.50 | 0.46–0.53 | <0.001 |
| I am concerned about serious adverse effects of vaccines | 1.87 | 1.72–2.03 | <0.001 | 1.14 | 1.05–1.18 | <0.001 | 1.56 | 1.44–1.68 | <0.001 |
| New vaccines carry more risks than older vaccines | 1.87 | 1.73–2.02 | <0.001 | 1.24 | 1.17–1.32 | <0.001 | 1.85 | 1.72–2.00 | <0.001 |
| Serious adverse reactions may occur due to the vaccination | 1.82 | 1.69–1.97 | <0.001 | 1.56 | 1.48–1.64 | <0.001 | 2.28 | 2.11–2.45 | <0.001 |
| I have difficulty getting immunized (no time, far medical institutions, etc.) | 1.48 | 1.40–1.57 | <0.001 | 1.56 | 1.48–1.65 | <0.001 | 1.86 | 1.76–1.97 | <0.001 |
| I do not need vaccines for diseases that are not common anymore | 1.30 | 1.21–1.39 | <0.001 | 1.35 | 1.28–1.43 | <0.001 | 1.55 | 1.45–1.65 | <0.001 |
| It is not necessary to take voluntary vaccination | 2.24 | 2.08–2.41 | <0.001 | 1.42 | 1.35–1.50 | <0.001 | 2.26 | 2.11–2.42 | <0.001 |
| I do not need vaccines if everyone around me is immunized | 1.83 | 1.71–1.95 | <0.001 | 1.63 | 1.53–1.73 | <0.001 | 2.21 | 2.07–2.36 | <0.001 |
| It is easy to obtain correct information on immunization | 0.66 | 0.62–0.71 | <0.001 | 0.75 | 0.71–0.80 | <0.001 | 0.60 | 0.56–0.64 | <0.001 |
| It is easy to understand why immunization is needed. | 0.63 | 0.59–0.67 | <0.001 | 0.75 | 0.71–0.80 | <0.001 | 0.62 | 0.58–0.66 | <0.001 |
| I have been able to accurately understand the vaccinations I have received | 0.79 | 0.74–0.84 | <0.001 | 0.59 | 0.55–0.62 | <0.001 | 0.56 | 0.53–0.60 | <0.001 |
| Recognition of COVID-19 | |||||||||
| I know a lot about COVID-19 | 0.88 | 0.82–0.95 | <0.001 | 0.73 | 0.69–0.77 | <0.001 | 0.77 | 0.72–0.83 | <0.001 |
| Anyone with COVID-19 will have symptoms. | 0.86 | 0.81–0.93 | <0.001 | 1.07 | 1.01–1.13 | 0.003 | 1.10 | 1.03–1.17 | 0.006 |
| Many people with COVID-19 have mild illnesses. | 1.09 | 1.03–1.16 | 0.003 | 1.04 | 0.99–1.09 | 0.139 | 1.16 | 1.10–1.23 | <0.001 |
| COVID-19 is more severe in people over 65 years old and those with chronic illnesses. | 0.80 | 0.75–0.87 | <0.001 | 0.82 | 0.77–0.88 | <0.001 | 0.81 | 0.7–0.87 | <0.001 |
| COVID-19 easily spreads from person to person. | 0.79 | 0.73–0.85 | <0.001 | 0.89 | 0.83–0.94 | <0.001 | 0.83 | 0.77–0.89 | <0.001 |
| I am worried about getting COVID-19. | 0.66 | 0.62–0.71 | <0.001 | 0.99 | 0.93–1.04 | 0.602 | 0.74 | 0.70–0.80 | <0.001 |
| I may get a new type of COVID-19. | 0.80 | 0.75–0.86 | <0.001 | 1.01 | 0.95–1.07 | 0.743 | 0.75 | 0.70–0.81 | <0.001 |
| Once you have COVID-19, you cannot get it again. | 0.87 | 0.80–0.94 | <0.001 | 1.10 | 1.03–1.18 | 0.004 | 1.03 | 0.95–1.12 | 0.513 |
| Recognition of COVID-19 vaccine | |||||||||
| Preventing inoculated individuals from becoming seriously ill with COVID-19. | 0.47 | 0.44–0.51 | <0.001 | 0.70 | 0.65–0.76 | <0.001 | 0.57 | 0.53–0.61 | <0.001 |
| Prevention of COVID-19 in vaccinated persons. | 0.49 | 0.46–0.52 | <0.001 | 0.84 | 0.79–0.89 | <0.001 | 0.65 | 0.61–0.69 | <0.001 |
| Prevent family members and friends of the inoculated person from contracting COVID-19. | 0.58 | 0.54–0.61 | <0.001 | 0.85 | 0.81–0.90 | <0.001 | 0.65 | 0.61–0.69 | <0.001 |
| Prevent the spread of COVID-19 in the vaccinated person’s area. | 0.45 | 0.42–0.48 | <0.001 | 0.73 | 0.69–0.78 | <0.001 | 0.56 | 0.53–0.60 | <0.001 |
| I am concerned about adverse reactions to the COVID-19 vaccine. | 2.09 | 1.92–2.30 | <0.001 | 1.57 | 1.49–1.65 | <0.001 | 2.67 | 2.46–2.90 | <0.001 |
| You may experience fever or swelling at the vaccination site after receiving the COVID-19 vaccine. | 1.32 | 1.20–1.43 | <0.001 | 0.84 | 0.78–0.90 | <0.001 | 1.02 | 0.94–1.10 | 0.634 |
AOR: Adjusted for age and sex. The significance level was set at 0.05/14 = 0.0036 for the category of vaccine confidence and literacy and 0.05/8 = 0.0063 for the category of Recognition of COVID-19 using the Bonferroni method. For the category of Recognition of COVID-19 vaccine, the value was 0.05/6 = 0.0084.