Placebo), the incidence risk of pneumonitis was also increased by PD-1/PD-L1 inhibitors (OR = 2.53, 95%CI [1.59, 4.02], I2 = 40%, Z = 3.94(P < 0.0001); Fig. 2C) [69–73, 75–80]. This evidence concerns the gene PDCD1 and pneumonitis.