Aberrations in Oxidative Stress Markers in Amyotrophic Lateral Sclerosis: A Systematic Review and Meta-Analysis

Figure 4

Funnel plots examining publication bias in studies comparing blood uric acid (a), GSH (b), and MDA (c) levels between cases and controls. GSH: glutathione; MDA: malondialdehyde.

(a)

(b)

(c)