BACKGROUND: The Glasgow coma scale (GCS) was introduced as a scoring system for 
patients with impaired consciousness after traumatic brain injury (TBI). Since, 
it has become the worldwide standard in TBI assessment. The GCS has repeatedly 
been criticized for its several failures to reflect verbal reaction in intubated 
patients, and to test brain stem reflexes. Recently, the full outline of 
unresponsiveness (FOUR) score was introduced, which is composed of four 
clinically distinct categories of evaluation: eye reaction, motor function, 
brainstem reflexes and respiratory pattern. This study aims to validate the FOUR 
score in neurosurgical patients.
METHODS: FOUR score and GCS were assessed in a consecutive series of 
neurosurgical patients with severely impaired consciousness (GCS < 9). Their 
correlation with the 30-day Glasgow outcome score (GOS) was compared. Patients 
admitted for TBI, spontaneous intracranial hemorrhage (intracerebral hemorrhage, 
aneurysmal subarachnoid hemorrhage, cerebellar hemorrhage), or malignant middle 
cerebral artery infarction were included.
RESULTS: We assessed a total of 101 patients (mean age = 64y, SD = 36.1y). The 
area under the curve (AUC) for mortality was 0.768 (P = 0.0001) for the FOUR 
Score, and 0.699 (P = 0.001) for the GCS. For poor outcome (GOS = 2-3) the FOUR 
score AUC was 0.683 (P = 0.018), the GCS AUC was 0.682 (P = 0.019). The FOUR 
score value for favorable outcome (GOS = 4-5) was 0.748 (P = 0.001), the 
corresponding GCS value was 0.704 (P = 0.002).
CONCLUSIONS: The FOUR score was more robust than the GCS in predicting mortality 
after 30 days in neurosurgical patients with severely impaired consciousness. 
There was no relevant difference in predicting poor and good outcome.