Discrimination of brain-damaged, depressed, and normal subjects using the Woodcock-Johnson tests of cognitive ability-revised

The purpose of this investigation was to examine the validity of the Woodcock Johnson Tests of Cognitive Ability-Revised (WJTCA-R) in discriminating between individuals with neurological or psychiatric impairments and those without known impairment. The primary question was whether WJTCA-R Standard Battery test scores significantly differentiated between individuals with brain-damage (n = 36), depression (n = 21), and without known impairments (n = 32). Archival data obtained for the development of a new neuropsychological assessment measure utilizing the WJTCA-R was analyzed. The results of a discriminant functions analysis indicated that significant differences between the groups existed on the WJTCA-R. Based on WJTCA-R Standard Battery performance alone, participants had a 53% chance of being correctly classified into their diagnostic group. Brain-damaged individuals had the best chance of being correctly classified while correct classification of depressed individuals was only slightly greater than that obtained from random assignment. In addition to moderately supporting the use of a multi-factored, theory-driven assessment instrument, the results of this study have clinical relevance for the development of diagnosis-specific recommendations for brain-damaged and depressed individuals.Department of Educational PsychologyThesis (Ph. D.