Multidimensional Malingering Criteria for Neuropsychological Assessment: A 20-Year Update of the Malingered Neuropsychological Dysfunction Criteria

Objectives Empirically informed neuropsychological opinion is critical for determining whether cognitive deficits and symptoms are legitimate, particularly in settings where there are significant external incentives for successful malingering. The Slick, Sherman, and Iversion (1999) criteria for malingered neurocognitive dysfunction (MND) are considered a major milestone in the field’s operationalization of neurocognitive malingering and have strongly influenced the development of malingering detection methods, including serving as the criterion of malingering in the validation of several performance validity tests (PVTs) and symptom validity tests (SVTs) (Slick, D.J., Sherman, E.M.S., & Iverson, G. L. (1999). Diagnostic criteria for malingered neurocognitive dysfunction: Proposed standards for clinical practice and research. The Clinical Neuropsychologist, 13(4), 545–561). However, the MND criteria are long overdue for revision to address advances in malingering research and to address limitations identified by experts in the field. Method The MND criteria were critically reviewed, updated with reference to research on malingering, and expanded to address other forms of malingering pertinent to neuropsychological evaluation such as exaggeration of self-reported somatic and psychiatric symptoms. Results The new proposed criteria simplify diagnostic categories, expand and clarify external incentives, more clearly define the role of compelling inconsistencies, address issues concerning PVTs and SVTs (i.e., number administered, false positives, and redundancy), better define the role of SVTs and of marked discrepancies indicative of malingering, and most importantly, clearly define exclusionary criteria based on the last two decades of research on malingering in neuropsychology. Lastly, the new criteria provide specifiers to better describe clinical presentations for use in neuropsychological assessment. Conclusions The proposed multidimensional malingering criteria that define cognitive, somatic, and psychiatric malingering for use in neuropsychological assessment are presented.

Exaggerated Functional Impairment due to Malingered Neurocognitive Dysfunction Following Mild Traumatic Brain Injury

Objective Functional impairment associated with Neurocognitive Disorder is often claimed in medico-legal settings after mild Traumatic Brain Injury (mTBI). This case–control study examined self-reported functional impairment and the plausibility of chronic disability claims following uncomplicated mTBI. Method Independent Medical Evaluations included a battery of performance and symptom validity tests, along with self-reports of physical or emotional complaints and functional impairment. Slick and colleagues’ (Slick, D. J., Sherman, E. M., & Iverson, G. L. (1999). Diagnostic criteria for malingered neurocognitive dysfunction: Proposed standards for clinical practice and research. The Clinical Neuropsychologist, 13, 545–561.) criteria ruled out probable malingering in 21 mTBI cases without psychiatric comorbidity and their self-reports were compared to those of seven non-malingering cases with a psychiatric comorbidity, 17 who were probable malingerers, and 31 orthopedic pain sufferers. Coherence Analysis of medical documentation corroborated assignment of mTBI cases to non-malingering versus probable malingering groups. Results Probable malingerers reported more postconcussion symptoms than non-malingerers (d = 0.79) but they did not differ significantly on tests of neurocognitive performance. Probable malingerers and orthopedic pain patients gave significantly higher ratings of functional impairment (d = 1.28 and 1.26) than non-malingerers. Orthopedic pain patients reported more disability due to pain than non-malingerers (d = 1.03), but pain catastrophizing was rated more highly by the probable malingerers (d = 1.21) as well as by the orthopedic pain patients (d = 0.98). The non-malingerers reported lower emotional distress than the other three groups, but only the probable malingerers reported elevated depression symptoms compared to the non-malingerers (d = 1.01). Conclusions The combined evaluation of performance validity, function, and coherence analysis would appear to enhance the difficult clinical evaluation of postconcussion symptoms in the medical-legal setting.

Detection of Malingered Neurocognitive Dysfunction Among Patients with Acquired Brain Injuries

The Word Memory Test (WMT) is one of the most sensitive forced-choice tests available designed to evaluate negative response bias (NRB). Presently there is no valid verbal test designed to evaluate NRB for Hebrew-speaking patients. The aims of the present study were to validate the response bias measures of the WMT among Hebrew-speaking patients with acquired brain injuries and to reveal the malingering base rate among Israeli patients involved in compensation-seeking. Participants were 112 patients. The Test of Memory Malingering (TOMM) was used for convergent validity and injury related variables were used for concurrent validity. A translated version of the WMT had high split-half reliability. Regarding convergent validity, WMT effort measures had high positive correlations with the TOMM. Moreover, based on TOMM cutoff scores for classification, the WMT had reasonable classification rates. Regarding concurrent validity, multivariate logistic regression revealed that failure in the WMT was significantly predicted by normal brainscans and involvement in compensation-seeking behavior. The baserate of probable malingering was 34%. These findings emphasize the universality of the WMT in detecting NRB and establishing a malingered neurocognitive dysfunction baserate among Israeli patients involved in compensation-seeking.