Table 3.

Mean scores and pairwise comparisons for Influenza and COVID-19 responses (N = 1,660).

Construct	Seasonal Influenza	COVID-19-19	T-test	Effect Size, Cohen’s d
	Mean (SD)	Mean (SD)
Intention	3.27 (1.33)	3.11 (1.07)	t(1,659) = 5.74, p < .001	d = 0.14
Vaccine Attitudes	3.81 (1.09)	3.76 (1.10)	t(1,659)= −2.29, p = .022	d = 0.06
Subjective Norms	2.62 (0.97)	3.16 (0.89)	t(1,659)= −22.47, p < .001	d = 0.05
Perceived Severity	2.64 (1.02)	3.01 (1.03)	t(1,659)= −19.104, p < .001	d = 0.51
Anticipated regret	3.28 (1.27)	3.55 (1.30)	t(1,659)= −12.61, p < .001	d = 0.31
Knowledge sufficiency	3.56 (1.03)	2.56 (1.11)	t(1,659) = 31.95, p < .001	d = 0.78
Vaccine benefits	2.90 (0.70)	2.93 (0.75)	t(1,659)= −1.30, p > .05	d = 0.03
Vaccine safety/side effects	3.69 (0.87)	3.11 (0.84)	t(1,659) = 29.86, p < .001	d = 0.73
Trust to Authorities	3.64 (0.93)	3.16 (0.97)	t(1659) = 24.56, p < .001	d=0.60
Perceived control	4.10 (0.99)	3.45 (1.11)	t(1,659) = 22.32, p < .001	d = 0.55
Susceptibility	2.44 (1.09)	2.55 (1.11)	t(1,659)= −4.521, p < .001	d = 0.11
Sub-analyses
Vaccine perceived safety (per each component):
Mild vaccine side effects	3.61 (0.95)	3.02 (0.85)	t(1,659) = 25.83, p < .001	d = 0.63
Vaccine fully tested	3.77 (0.96)	3.22 (1.01)	t(1659) = 25.57, p < .001	d = 0.63
Attitudes (per each component):
Worthless/Valuable	3.61 (1.33)	3.71 (1.25)	t(1,659) = 3.48, p < .001	d = 0.09
Harmful/Beneficial	3.79 (1.18)	3.73 (1.23)	t(1,659)= −2.48, p < .05	d = 0.06
Painful/Tolerable	4.03 (1.14)	3.84 (1.18)	t(1,659)= −7.76, p < .001	d = 0.19