Prognosis of six-month functioning after moderate to severe traumatic brain injury: a systematic review of prospective cohort studies

Objective: To systematically review which determinants, assessed within the first month after a moderate to severe traumatic brain injury, predict 6-month functional outcome. Methods: Databases were searched for relevant publications between 1995 and August 2008. Selection criteria were: prospective cohort studies; determinants associated with functional outcome 6 months after moderate to severe traumatic brain injury in adult patients; determinants assessed within the first month post-injury. Two reviewers independently performed the selection and quality assessment. A best-evidence synthesis was performed for prognostic factors assessed in 2 or more studies. Results: Twenty-eight studies were included, 27 of which were high quality. Most studies used the Glasgow Outcome Score at 6 months post-injury as outcome measure, sometimes in combination with other outcome measures. Strong evidence for predicting outcome at 6 months was found for the Glasgow Coma Scale (GCS), GCS admission, motor score, midline shift on computed tomography scan, subdural haematoma and pulsatility index. Strong evidence of no association was found for gender and intraventricular haemorrhage. For other determinants, inconclusive or no evidence was found. Conclusion: GCS, GCS on admission, motor score, midline shift, subdural haematoma and pulsatility index predicted outcome 6 months after traumatic brain injury. Gender and intraventricular haemorrhage did not have predictive value.