تشخیص تمارض عصب: اثرات مربیگری و اطلاعات

Concerns that patients presenting for neuropsychological assessment may not be putting forth maximum effort during testing has prompted the development of measures designed to detect malingering and incomplete effort. Two of these measures are the Computerized Assessment of Response Bias-97 (CARB-97) and Word Memory Test (WMT). Despite widespread use of these instruments, no study has been published determining the vulnerability of neuropsychological malingering measures to explicit coaching or brain injury information. The present study, using analog participants, found that the CARB-97 and WMT differentiate “normal” from “malingered” instructional sets, and show little difference between naı̈ve and coached malingering efforts. There was also little difference between providing brain injury information and a no-information condition, but when effects were present, the information group generally scored worse. Further, it was found that response times (RTs), in addition to items correct, may also be effective in detecting those who are not giving their full effort.

Clinical neuropsychological assessment is commonly performed following brain injury or other neurological insult. Accurate assessment, however, is dependent upon the patient putting forth his or her best possible effort (Bernard, 1990). It is, therefore, startling to learn that an estimated 70% or more of patients assessed by a clinical neuropsychologist in a forensic context are thought to alter their presentations (Heilbrun, Bennett, White, & Kelly, 1990). Youngjohn, Burrows, and Erdal (1995) speculates that almost half of all workers’ compensation claims may involve faked cognitive deficits. With such seemingly high base rates, clinicians must routinely consider that patients may not be completely honest about their condition, or may not be putting forth their best possible effort during testing. There are several commercially available instruments that have been designed specifically to evaluate the effort put forth during neuropsychological testing and to assess dissimulation. Although many of these instruments are generally thought to identify incomplete effort or malingering with at least partial success, new concerns are arising in the literature. Some patients may have access to information about how to exaggerate symptoms in a believable way or, worse, some are being deliberately coached about how to defeat malingering measures. Concerns have been raised that patients may be going to great lengths to defeat malingering measures on the advice of unethical attorneys (Lees-Haley, 1997). Youngjohn (1995) confirms the instance of an attorney coaching a client prior to neuropsychological testing and providing him with literature regarding malingering measures and simulating injury. If malingerers are able to perform convincingly on these measures, then truly accurate neuropsychological assessment becomes very difficult. It is important, therefore, to understand the impact on malingering measures of receiving coaching as to how to perform on certain tests convincingly or receiving information about the behavioral effects of brain injury.