The juvenile group showed the largest (3.54 SMD, 95% CI, 2.79 to 4.29) and the group where age was not stated the smallest (2.20 SMD, 95% CI, 1.81 to 2.58), reduction in the abundance of SOD (χ2 = 283.09, Τ2 = 1.73, I2 = 78.8%, d.f. = 60, p<0.0005; Fig 4A).