Pneumococcal Vaccination in Adults: What Can We Learn From Observational Studies That Evaluated PCV13 and PPV23 Effectiveness in the Same Population? Eileen M. Dunne; Catia Cilloniz; Claire von Mollendorf; Joseph Lewnard; Lindsay R. Grant; Mary P.E. Slack; Luis Jodar; Christian Theilacker; Bradford D. Gessner;