Table 3. Univariate and multivariate linear regression analysis: Standardized Beta coefficients of independent variables assessed in the study group after receiving a 2nd dose of the ChAd vaccine (n = 63) and in the cohort participating in the post-booster follow-up (n = 40).

Parameters	Early follow-up– 14–21 days after receiving 2nd dose of ChAdOx1 vaccine, n = 63
	Univariate analysis			Multivariate analysis* (adjusted R2 = 0.23)
	B	SE	p	B	SE	p
age ≥ 60	-0.01	0.10	0.953	-0.02	0.11	0.869
seropositivity before the study started 1	0.21	0.06	0.001	0.17	0.06	0.008
smoking	-0.17	0.09	0.072	0.12	0.09	0.167
allergy	0.06	0.13	0.654	0.00	0.12	0.967
obesity	0.15	0.07	0.037	0.00	0.10	0.995
NFF	0.11	0.05	0.026	0.11	0.05	0.057
FF	0.13	0.05	0.020	0.14	0.06	0.036
Parameters	Post-booster follow-up—21 days after receiving the BNT162b2 booster, n = 40
	Univariate analysis			Multivariate analysis** (adjusted R2 = 0.19)
	B	SE	p	B	SE	p
age ≥ 60	0.09	0.08	0.258	0.10	0.09	0.272
seropositivity before the study started 1	0.13	0.05	0.027	0.06	0.06	0.333
smoking	-0.12	0.07	0.079	0.07	0.06	0.250
allergy	-0.01	0.11	0.962	-0.02	0.10	0.854
obesity	0.15	0.06	0.022	0.01	0.10	0.886
NFF	0.09	0.04	0.022	0.09	0.05	0.094
FF	0,08	0.05	0.086	0.06	0.06	0.319

¹seropositivity before the study started–anti-SARS-CoV-2 IgG titers ≥ 10.00 AU/mL before the first vaccine dose

*Durbin-Watson parameter is equal 1.87

**Durbin-Watson parameter is equal 2.04.

Abbreviations. R–linear regression coefficient, B—logistic regression coefficient, SE–standard error, p–statistical significance, NFF—non-fat factor, FF—fat factor.