Neuropsychological outcome and recovery of a group of 91 patients with mode
rate-to-severe head injuries were prospectively investigated over a 2 year
period, with evaluations at acute hospital discharge at 6 months and 2 year
s post-injury. A group of 39 trauma patients with injuries to parts of the
body other than the head were used as controls. The head injured group perf
ormed significantly worse than the control group at baseline, 6 months and
2 years post-injury. Significant improvement was found during the first 6 m
onths, but also between 6 months and 2 years post-injury. Trauma controls a
lso performed significantly better at 6 months post-injury compared to base
line. Differential practice effects between groups cause difficulties in de
termining recovery. Within the head injured group, three distinct recovery
groups were identified varying as a function of coma-length and coma-durati
on. The first group is comparable with the trauma controls. The other two g
roups demonstrate significant neuropsychological impairments at baseline, w
ith one group showing a marked improvement over the 2 year period, and the
other group showing only small improvement over this time period.