Psychological characteristics contributing to performance on neuropsychological tests and effort testing.

The issue of effortful patient performance has been an area of clinical interest in individuals with minor traumatic brain injury (mTBI). Clinical attention to this area has increased largely because of an increase in the number of worker's compensation claims, injury-related lawsuits and/or insanity defense pleas. As patients are presented with the opportunity for secondary gain, the issue of optimum performance on neuropsychological measures becomes salient. In addition to neurocognitive deficits, there are psychological characteristics associated with mTBI including depression, emotional disturbance, personality changes, and other psychopathology. This study utilized the MSVT, a set of standard neuropsychological instruments, and the Minnesota Multiphasic Inventory-2 (MMPI-2) to investigate the relationships between effort, psychological characteristics, and neuropsychological functioning in individuals with minor traumatic brain injuries. The first objective of this study was to determine which psychological factors were related to effort in mTBI. The second objective was to determine if there were differences between groups that performed poorly on effort testing and groups that performed adequately on effort testing, based on relevant psychological characteristics. The results of the analyses supported the first hypothesis. Hysteria was inversely related to effort, and Mania was positively related to effort on one of five measures of effort. The second hypothesis was not supported