ABSTRACT

The factor structure of EF tasks has been explored in one study of children following TBI. Levin, Fletcher, Kufera, et al. (1996) examined the factor structure of EF measures in a group of head-injured and normal children by completing a principal components analysis of data collected from a series of tests designed to measure concept formation and problem solving, planning, verbal fluency, design fluency, memory, and response modulation. The five-factor solution obtained in this initial study included the following: Conceptual-Productivity (e.g., word fluency), Planning (e.g., Tower of London), Schema (e.g., Twenty Questions Test), Semantic Clustering (e.g., California Verbal Learning Test), and Inhibition (e.g., Go-No Go task). Severity of injury had a significant effect on four factors and age at testing had a significant effect for three of the five factors. In view of the relatively small sample size ofthis initial factor analytic study, Levin, Fletcher, Kufera, et al. (1996) recommended further research to explore the dimensionality of the EF measures with a larger sample of head-injured children, using alternative methods of factor analysis.