Comparative Effectiveness of Pneumococcal Vaccination Strategies to Prevent Invasive Pneumococcal Disease: A Population-Based Cohort Study at the Veterans Health Administration in the United States

Comparative effectiveness of pneumococcal 13-valent conjugate vaccine (PCV13), 23-valent polysaccharide vaccine (PPSV23), and their combinations for adults in preventing invasive pneumococcal disease (IPD) has yet to be thoroughly investigated. We aimed to estimate the comparative effectiveness of preventing IPD, using population-based data from the Veterans Health Administration (VHA) in the United States (US).