Subtypes of psychopathology in children referred for neuropsychological assessment.
The validity of a Personality Inventory for Children-Revised edition (PIC-R) typology was examined in a sample of 323 children aged 6-16 years. These children had been referred to a children's mental health centre for neuropsychological assessment. In study 1, K-means cluster analysis (k = 12) was applied to the PIC clinical scales in an attempt to replicate the 12 clusters identified by Gdowski, Lachar, and Kline (1985). Partial cluster replication was achieved. Examination of the obtained clusters revealed significant overlap, suggesting that fewer clusters would represent an optimal solution. In study 2, a two-stage cluster analysis yielded a seven-cluster solution consistent with several key forms of psychopathology previously reported in the literature using specific neuropsychological populations. Identified subtypes included profiles characterized as: normal, cognitive deficit, cognitive deficit with internalized psychopathology, cognitive deficit with social impairment, cognitive deficit with hyperactivity, cognitive deficit with both internalized and externalized psychopathology, and combined internalized and externalized psychopathology without a cognitive deficit component.