Effects of coaching on detecting feigned cognitive impairment with the Category Test

In a replication and extension of previous research (Tenhula & Sweet, 1996) , the current study investigated the utility of the Category Test (CT) for detecting feigned cognitive impairment. Ninety-two undergraduate participan ts were randomly assigned to one of three groups and administered the CT. A Coached Simulator group was instructed to simulate cognitive impairment an d was provided lest-taking strategies to avoid detection. An Uncoached Simu lator group was simply insmrcred to feign impairment. A control group was i nstructed to perform optimally. In addition, the CT results of 30 traumatic brain injury (TBI) patients were analyzed. The results largely supported t he utility of five CT malingering indicators identified by TenhrLla and Swe et: (a) number of errors on subtests I and II, (6) number of errors errors on subtest VII, (c) total CT errors, (d) number of errors on 19 "easy" item s, and (e) number of criteria exceeded. Correct Classification rates of the five indicators for Uncoached Simulators and optimal performance controls ranged from 87% to 98%. Correct Classification rates for the TBI patients r anged from 70% to 100%. In addition, significantly more Coached Simulators were misclassified as nonsimulators on four of the CT malingering indicator s, relative to their Uncoached counterparts. A decision rule of > I error o n subtests I and II was consistently the most accurate malingering indicato r, regardless of degree of coaching or presence of TBI. This indicator corr ectly classified 76% of all simulators and 100% of the optimal performance controls and TBI patients. Implications of providing persons with test-taki ng strategies and the utility of these CT malingering indicators for variou s populations are discussed. (C) 2000 National Academy of Neuropsychology. Published by Elsevier Science Ltd.