Table 3. Adjusted Analysis on the Associations Between External/Internal Factors and BICV Under Scenario 1 and Immediate Vaccination .
| Variables |
S1: 80% + Rare MSE + Free
(Likely/Definitely Yes) |
Vaccination at the
Soonest |
| ORa (95% CI) | ORa (95% CI) | |
| External Factors of BICV | ||
| Overall trust toward government | ||
| Very strong mistrust/mistrust | Ref = 1.0 | Ref = 1.0 |
| Neutral | 3.99 (1.99-7.99)d | 2.93 (0.70-12.33) |
| Trust/very strong trust | 8.22 (4.12-16.41)d | 9.39 (2.40-36.76)c |
| Don’t know | 4.17 (0.87-19.99)a | 5.71 (0.42-77.47) |
| Trust toward governmental measures in controlling COVID-19 | ||
| Very strong mistrust/mistrust | Ref = 1.0 | Ref = 1.0 |
| Neutral | 2.73 (1.40-5.33)c | 3.69 (0.84-16.21)a |
| Trust/very strong trust | 7.39 (3.74-14.61)d | 11.97 (2.75-52.13)c |
| Overall satisfaction with government | ||
| Very strong dissatisfaction/Dissatisfaction | Ref = 1.0 | Ref = 1.0 |
| Neutral | 4.22 (2.16-8.25)d | 6.16 (1.23-30.87)b |
| Satisfaction/very strong satisfaction | 8.97 (4.41-18.24)d | 17.43 (3.42-88.85)c |
| Don’t know | 3.54 (0.58-21.60) | 10.75 (0.67-172.44)a |
| Frequency of exposure to positive social media messages about COVID-19 vaccines | ||
| Extremely/quite infrequent | Ref = 1.0 | Ref = 1.0 |
| Average | 0.96 (0.58-1.57) | 0.58 (0.28-1.20) |
| Extremely/quite frequent | 3.02 (1.69-5.39)d | 1.35 (0.61-3.02) |
| Don’t know | NA | NA |
| Internal Factors of BICV | ||
| Descriptive norms | ||
| Perceived level of vaccination among Hong Kong citizense | 1.34 (1.18-1.53)d | 1.15 (0.95-1.40) |
| Perceived level of vaccination among acquaintancese | 1.48 (1.32-1.66)d | 1.41 (1.22-1.63)d |
| Perceived impact of COVID-19 vaccine on controlling COVID-19 in Hong Kong | ||
| Very low/quite low | Ref = 1.0 | Ref = 1.0 |
| Moderate | 0.97 (0.41-2.32) | 1.31 (0.43-3.95) |
| Quite strong/very strong | 3.56 (1.54-8.20)c | 2.04 (0.16-25.98) |
| Don’t know | 0.72(0.07-7.18) | |
| Perceived duration of effectiveness of the COVID-19 vaccine | ||
| <1 year | Ref = 1.0 | Ref = 1.0 |
| ≥1 year | 2.65 (1.58-4.45)d | 2.83 (1.14-7.02)b |
| Don’t know | 0.80 (0.47-1.36) | 3.06 (1.28-7.36)b |
| Perceived risk | ||
| Low/very low | Ref = 1.0 | Ref = 1.0 |
| Moderate | 1.38 (0.88-2.17) | 1.45 (0.77-2.75) |
| High/very high | 0.60 (0.29-1.21) | 0.24 (0.07-0.79)b |
| Life satisfactione | 1.43 (1.15-1.78)c | 1.43 (1.00-2.04)b |
| Influenza vaccination in the past 12 months | ||
| No | Ref = 1.0 | Ref = 1.0 |
| Yes | 2.11 (1.29-3.45)c | 3.50 (1.79-6.81)d |
| Don’t know | NA | NA |
Abbreviations: BICV, behavioral intention for COVID-19 vaccination; ORa, adjusted odds ratio (the models were adjusted for sex, age groups, educational level, current marital status, having children under 18, employment status, and chronic disease status); Ref: reference group; DV, dependent variable; NA, not applicable; MSE, mild side effects; SE, side effect.
Note. Scenario 1: COVID-19 vaccine of 80% effectiveness, rare MSE, and free.
a.05 < P <.10; bP < .05; cP < .01; dP < .001; e Those who answered “don’t know” and refused to answer were excluded from the analysis.