A meta-analysis of neuropsychological outcome after mild traumatic brain injury: re-analyses and reconsiderations of Binder et al. (1997), Frencham et al. (2005), and Pertab et al. (2009)

The meta-analytic findings of Binder et al. (1997) and Frencham et al. (2005) showed that the neuropsychological effect of mild traumatic brain injury (mTBI) was negligible in adults by 3 months post injury. Pertab et al. (2009) reported that verbal paired associates, coding tasks, and digit span yielded significant differences between mTBI and control groups. We re-analyzed data from the 25 studies used in the prior meta-analyses, correcting statistical and methodological limitations of previous efforts, and analyzed the chronicity data by discrete epochs. Three months post injury the effect size of -0.07 was not statistically different from zero and similar to that which has been found in several other meta-analyses (Belanger et al., 2005; Schretlen & Shapiro, 2003). The effect size 7 days post injury was -0.39. The effect of mTBI immediately post injury was largest on Verbal and Visual Memory domains. However, 3 months post injury all domains improved to show non-significant effect sizes. These findings indicate that mTBI has an initial small effect on neuropsychological functioning that dissipates quickly. The evidence of recovery in the present meta-analysis is consistent with previous conclusions of both Binder et al. and Frencham et al. Our findings may not apply to people with a history of multiple concussions or complicated mTBIs.     

Sensitivity to brain dysfunction of the Halstead-Reitan vs an ability-focused neuropsychological battery

We compared the sensitivity to brain dysfunction of an ability focused neuropsychological battery (AFB), as a proxy for the core of a flexible battery, to the Halstead-Reitan Battery (HRB). The AFB was designed to represent constructs of language function, fine motor skill, working memory, processing speed, verbal and visual memory, and verbal and visual abstraction and problem solving. Receiver operating characteristic analysis (ROC) yielded an area under curve (AUC) of. 86 for the AFB, versus. 83 for the HRB (p =. 50), for discriminating 54 patients with brain dysfunction due to various etiologies, from 69 non-neurologic medical controls. Additionally, Bayesian Model Averaging selected four tests from the combined set of AFB and HRB subtests, plus Trail Making B, which optimally discriminated the brain dysfunction from medical control patients: H-Words, Grooved Pegboard, Finger Tapping, and Trail Making B. These data support the current mainstream practice in neuropsychology of using an AFB (flexible battery) to assess brain dysfunction. In particular, tests involving processing speed appear to be among the most sensitive measures of brain dysfunction. The data do not support the superiority of the HRB to AFB approaches.     

American Academy of Clinical Neuropsychology Consensus Conference Statement on the Neuropsychological Assessment of Effort,Response Bias,and Malingering

During the past two decades clinical and research efforts have led to increasingly sophisticated and effective methods and instruments designed to detect exaggeration or fabrication of neuropsychological dysfunction, as well as somatic and psychological symptom complaints. A vast literature based on relevant research has emerged and substantial portions of professional meetings attended by clinical neuropsychologists have addressed topics related to malingering (Sweet, King, Malina, Bergman, & Simmons, 2002 Sweet, JJ, King, JH, Malina, AC, Bergman, MA and Simmons, A. 2002. Documenting the prominence of forensic neuropsychology at national meetings and in relevant professional journals from 1990 to 2000. The Clinical Neuropsychologist, 16: 481–494. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). Yet, despite these extensive activities, understanding the need for methods of detecting problematic effort and response bias and addressing the presence or absence of malingering has proven challenging for practitioners. A consensus conference, comprised of national and international experts in clinical neuropsychology, was held at the 2008 Annual Meeting of the American Academy of Clinical Neuropsychology (AACN) for the purposes of refinement of critical issues in this area. This consensus statement documents the current state of knowledge and recommendations of expert clinical neuropsychologists and is intended to assist clinicians and researchers with regard to the neuropsychological assessment of effort, response bias, and malingering.