Objective: This study examined the correlation between the worst abbreviated injury scale 1990 (AIS) intracranial severity score and outcome following severe head injury.
Design: The initial CT scans of 109 severely head injury patients were examined by a neuroradiologist and classified according to the worst applicable intracranial severity code from the AIS. This score was then correlated with the glasgow outcome scale (GOS) at 6 months. For comparison, the GOS was also correlated with the diffuse injury scale (DIS) described by L.F. Marshall et al. [5], the worst post-resuscitation Glasgow coma score (GCS) in the first 24 h, and the head injury outcome prediction tree described by Choi et al. [1].
Results: Our results show Spearman rank correlation coefficients of 0.58 (p < 0.001), 0.47 (p < 0.001), 0.45 (p < 0.001), and 0.31 (p < 0.01) for the correlation between the AIS, prediction tree, DIS, and GCS respectively and the GOS. Independent outcome (i.e. GOS good or moderate) was strongly predicted by an AIS of 3 or less (positive predictive value 95%, specificity 98%, sensitivity 40%, likelihood ratio 25:1). Death or vegetative survival was less strongly predicted in patients with an AIS of 5 (positive predictive value 71%, specificity 75%, sensitivity 67%, likelihood ratio 2.7:1).
Conclusion: The AIS, based on initial CT scan, provides useful prognostic information in patients with severe head injury.