Fig. 2.

Contributed factor for anti-spike IgG level ≥ 2150 AU/ml.

Odds ratios for anti-spike IgG level ≥ 2150 AU/ml (2a for univariate and 2b for multivariate) are shown. Adjusted factors in the multivariate logistic model were sex, generation, smoking habit, drinking habit, allergy status, and the interval days between the second vaccination and anti-spike IgG measurement. In the multivariate analyses, age and alcohol drinking habits significantly affected the anti-spike IgG level ≥ 2150 AU/ml.