Corrigendum: Key Determinants of Cell-Mediated Immune Responses: A Randomized Trial of High Dose Vs. Standard Dose Split-Virus Influenza Vaccine in Older Adults - Verschoor, Chris P.; Haynes, Laura; Pawelec, Graham; Loeb, Mark; Andrew, Melissa K.; Kuchel, George A.; McElhaney, Janet E. (Frontiers in Aging, 2021)