Pooled unadjusted estimates on the association between prior ICI exposure with risks of: a mortality, b severity, c hospitalization, and d ICU admission. ICI, immune checkpoint inhibitor. ICU, intensive care unit. aOverlapping populations were observed between Luo et al. [30] and Robilotti et al. [31], of which Robilotti [31] et al. was prioritized due to larger sample size