An impairment index of brain functions in children.

An impairment index of brain functions in children, based on the 1979 Rules System by Selz and Reitan, was developed to summarize the performance on the Halstead-Reitan Neuropsychological Test Battery for older children comparing groups of 25 normal, learning-disabled, and brain-damaged children aged 9 through 14 yr. Analysis of variance indicated a significant difference between all pairs of groups. A cut-off Impairment Index between .17 and .18 correctly differentiated 78% of the brain-damaged and control subjects. The findings suggested that the Impairment Index for Children may be a valid and objective indicator of brain functions in older children, although cross-validation is necessary.