Figure 3. Model-based opsonophagocytic activity (OPA) geometric mean ratios (GMRs) in participants aged ≥60 years for the 13 matched serotypes (20-valent pneumococcal conjugate vaccine [PCV20]/13-valent pneumococcal conjugate vaccine [PCV13]) ( A ) and 7 additional serotypes (PCV20/23-valent pneumococcal polysaccharide vaccine [PPSV23]) ( B ) 1 month after vaccination. Noninferiority was declared if the lower bound of the 2-sided 95% confidence interval (CI) for the GMR was >0.5 (2-fold criterion). Noninferiority criteria were met for all 13 matched serotypes between PCV13 and PCV20. Assay results below the lower limit of quantitation (LLOQ) were set to 0.5 × LLOQ in the analysis. GMRs (PCV20/control) and 2-sided CIs were calculated by exponentiating the difference in least-squares means and the corresponding CIs based on analysis of log-transformed OPA titers using a regression model including terms of vaccine group, age at vaccination in years (continuous), sex, smoking status, and baseline log-transformed OPA titers. The numbers of subjects with valid and determinate OPA titers for the specified serotype varied by serotype and were 1399–1430 for PCV20 and 1390–1419 for PCV13 for the 13 matched serotypes, and 1157–1374 for PCV20 and 1201–1319 for PPSV23 for the 7 additional serotypes.