Forensic neuropsychiatric evaluation of a personal injury case.

Civil litigation involving the forensic neuropsychiatric evaluation of a personal injury case requires an assessment of damages and causation. The expert witness is obliged to integrate data from three critical sources of information: the review of records; the results of neuropsychological testing; and the findings from the clinical examination. In civil litigation involving a personal injury claim, the expert witness can be expected to address causation and prognosis of any neuropsychiatric damages. We discuss the undertaking of a forensic neuropsychiatric evaluation, psychiatric disorders often encountered in personal injury litigation, provide case vignettes and describe a number of special types of forensic neuropsychiatric evaluations, for example, Workers' Compensation, VA Disability and Social Security Disability.

Screening for neuropsychological impairment using Reitan and Wolfson's preliminary neuropsychological test battery.

This study examined the utility of a screening battery developed by Reitan & Wolfson, 2006 for predicting neuropsychological impairment on the Halstead-Reitan neuropsychological test battery for adults. Using archival neuropsychological data from 69 litigants seen in a private practice setting, the Pearson correlation between the General Neuropsychological Deficit Scale (GNDS) score and the total Neuropsychological Deficit Scale (NDS) score from the screening battery (SBNDS) was .82. ROC curve analysis determined that the AUC was .88. Using a cutoff score of 9, as recommended by Reitan and Wolfson, the screening battery had excellent specificity but only fair sensitivity for identifying individuals with neuropsychological impairment on the Halstead-Reitan battery. Using a cutoff score of 8, the sensitivity and specificity of the screening battery was comparable to the findings of Reitan and Wolfson. The findings from this study indicate the optimal cutoff score for the screening battery may vary with different populations. The positive predictive power (PPP) and negative predictive power (NPP) were calculated for various base rates for cut scores with both sensitivity and specificity of greater than .600, and this information is provided.

Examining the Test Of Memory Malingering Trial 1 and Word Memory Test Immediate Recognition as screening tools for insufficient effort.

Assessing effort level during neuropsychological evaluations is critical to support the accuracy of cognitive test scores. Many instruments are designed to measure effort, yet they are not routinely administered in neuropsychological assessments. The Test of Memory Malingering (TOMM) and the Word Memory Test (WMT) are commonly administered symptom validity tests with sound psychometric properties. This study examines the use of the TOMM Trial 1 and the WMT Immediate Recognition (IR) trial scores as brief screening tools for insufficient effort through an archival analysis of a combined sample of mild head-injury litigants ( N = 105) who were assessed in forensic private practices. Results show that both demonstrate impressive diagnostic accuracy and calculations of positive and negative predictive power are presented for a range of base rates. These results support the utility of Trial 1 of the TOMM and the WMT IR trial as screening methods for the assessment of insufficient effort in neuropsychological assessments.

Hit rates of adequate performance based on the test of memory malingering (TOMM) Trial 1.

The Test of Memory Malingering (TOMM) is a method of identifying patients who may be exerting poor effort during neuropsychological testing. This study seeks to examine whether TOMM Trial 1 scores are useful in identifying patients whose overall TOMM performance does not indicate obvious poor effort. Hit rates of adequate performance on Trial 2 and the Retention Trial were calculated based on a fixed criterion of 45 or greater on Trial 1. Archival data were collected from a sample of 77 mild traumatic brain injured litigants and compared to each clinical sample described in the TOMM test manual (Tombaugh, 1996). Results show a hit rate of 100% for each group. Findings reveal that adequate Trial 1 scores predict adequate Trial 2 and Retention Trial scores, suggesting that patients scoring 45 or greater on Trial 1 are not likely to be suspected of poor effort based on overall TOMM performance.

Is poor performance on recognition memory effort measures indicative of generalized poor performance on neuropsychological tests?

The detection of suboptimal effort has become crucial in clinical neuropsychological practice in order to make accurate diagnoses, prognoses, and referrals. Symptom Validity Testing (SVT) has been the most commonly utilized model for assessing effort, and frequently includes recognition memory tasks. Some conflicting views on this model purport, however, that measures of effort gathered from a recognition memory paradigm do not necessarily extend to effort in other cognitive domains and other areas of performance. The present study sought to investigate whether performance on an SVT measure, which utilizes recognition memory, the TOMM, could predict performance on other measures that do not evaluate recognition memory or just memory per se in a group of mildly traumatic brain-injured litigants. Results indicated that poor performance on the TOMM was significantly correlated with poorer performance on the WAIS-R and the HRNB-A. Further, experimental exploration of these results indicated that the overall neuropsychological performance of litigants with suboptimal effort was poorer than what is generally expected from mild TBI individuals, and was also lower than the other mild TBI examinees in the study, who were not classified by the TOMM as exhibiting suboptimal effort. These findings support the proposition that poor effort as measured by recognition memory effort measures is not restricted to recognition and memory measures. In fact, in the present study it appears that a poor performance on the TOMM is predictive of a generalized poorer performance on standardized measures such as the WAIS-R and the HNRB-A.

Performance profiles and cut-off scores on the Memory Assessment Scales.

The increased role of neuropsychologists in the courtroom has led to an increased effort in the detection of possible symptom exaggeration/malingering. Whereas domain specific measures of malingering have traditionally been used in this detection process, the identification of performance profiles and cut-off scores on standard neuropsychological assessment instruments may provide an alternate strategy. The present study evaluated the effectiveness of performance profiles and cut-off scores in discriminating traumatic brain injury (TBI) litigants suspected of malingering from those not suspected of malingering on the Memory Assessment Scales (MAS). Results suggest that TBI litigants suspected of poor effort will perform globally at a lower level than TBI litigants not suspected of poor effort on nearly all MAS indices, however, the performance profiles of each group was similar. Cut-off scores, especially when used in combination, were also effective in correctly classifying individuals in the two groups. The present findings warrant further research examining the utility of the proposed cut-off scores separately and concomitantly. Such research will aid the clinical neuropsychological practitioner in interpreting aberrant performance profiles on the MAS in forensic situations.

Utility of the trail making test in the assessment of malingering in a sample of mild traumatic brain injury litigants.

The Trail Making Test (TMT) is one of the most commonly administered tests in neuropsychological assessments. It has been shown to be a valid indicator of brain damage due to traumatic brain injury (TBI), as well as a number of other neuropathological conditions. TMT error and ratio scores have been suggested as possible markers of malingering. The present study examined the utility of various TMT scores as malingering measures in 94 TBI litigants. Litigants were divided into those suspected of (n = 27) and those not suspected of malingering (n = 67) based on scores obtained on the Test of Memory Malingering and/or the Rey 15-Item Test. TMT errors did not discriminate between suspected and nonsuspected malingerers; however, the overall level of performance on the TMT was suppressed in suspected malingerers. The TMT ratio score was significantly lower in litigants suspected of malingering, although the clinical utility of this ratio is minimal. Results of the present study suggest using caution when interpreting TMT scores as markers of malingering in TBI litigants.