Figure 2.
Adjusted relative vaccine effectiveness, overall (4–64 years old), post–inverse probability of treatment weighting and Poisson regression. Abbreviations: COPD, chronic obstructive pulmonary disease; ER, emergency room; HIAP, high influenza activity period; IIV4c, cell-derived quadrivalent influenza vaccine; IIV4e, standard egg-derived quadrivalent influenza vaccine; rVE, relative vaccine effectiveness; UTI, urinary tract infection.