Which of the following markers has significant association with poor prognosis in traumatic brain injury?

After moderate or severe traumatic brain injury, serum S-100b protein concentrations are significantly associated with unourable prognosis in the sho, mid, or long term. Optimal thresholds for discrimination remain unclear. Measuring the S-100b protein could be useful in evaluating the severity of traumatic brain injury and in the determination of long term prognosis in patients with moderate and severe injury. S-100b protein serum concentrations correlate significantly with unourable prognosis in patients with moderate or severe traumatic brain injury, as defined by moality, Glasgow outcome score <=3, or brain stem death, with or without concomitant traumatic injuries. Ref: Predictive value of S-100b protein for prognosis in patients with moderate and severe traumatic brain injury: systematic review and meta-analysis ; BMJ 2013;346:f1757.