Components of executive function in typically developing and head-injured children.

To identify the key components of executive functions (EFs) in children following traumatic brain injury (TBI), data from a series of EF tests administered to 286 pediatric TBI patients at least 3 years postinjury were subjected to an exploratory factor analysis. A 5-factor model included discourse, EFs (e.g., problem solving, planning), processing speed (e.g., coding), declarative memory, and motor speed. Confirmatory factor analysis based on data obtained from 265 pediatric TBI patients at 3 months postinjury disclosed that the 5-factor model provided a good fit to the data. A second exploratory analysis of the 3-month postinjury data disclosed a 4-factor model in which processing speed and motor speed measures loaded on a common factor. Severity of TBI and age at test had significant effects on all factors in both the 5- and 4-factor models. Adaptive functioning, as measured by the Vineland Adaptive Behavioral Scale-Revised, was moderately related to factor scores at 3 years or longer postinjury, but weakly related to factor scores obtained at 3 months postinjury. The factor scores could be used in clinical trials to facilitate data reduction and appear to have validity as indicators of TBI outcome.