S100B and Stroke: Previous studies on S100b have shown its short half-life in blood and recommend a maximum delay of 3–6 h for sampling after the head trauma.14,15,17,26,28 GFAP increases more slowly after a head trauma and peaks at 20 h.29 HFABP as a marker of brain damage in stroke has been seen to peak already at 2–3 h and to remain elevated up to 120 h.30 In our cohort, we did two separated analyses of performances, depending on sampling time after the trauma (within 6 h and 24 h).