Figure 1. Relationship between number of previous concussions and baseline serum biomarker concentrations.

A significant but weak association was found between more previous concussions and higher baseline Aβ₄₂ levels (A). No other significant correlations were noted (B–G). Aβ₄₂ = β-amyloid peptide 42; CNPase = 2′,3′-cyclic-nucleotide 3′-phosphodiesterase; GFAP = glial fibrillary acidic protein; MAP2 = microtubule associated protein 2; S100B = S100 calcium binding protein B; SRC = sport-related concussion; UCH-L1 = ubiquitin carboxy-terminal hydrolyzing enzyme L1.