In deep SSI subgroup, the infection rate was 0.61 % (17/2767) in the albumin <3.5 g/dL group and 0.18 % (108/58,818) in the albumin >3.5 g/dL group, (RR = 2.62, 95 % CI [1.56 4.42], Z = 3.62, p = 0.0003) in a fixed model (I2 = 0 %). The gene discussed is ALB; the disease is infection.