Laurence M. Binder

A review of mild head trauma. part I: Meta-analytic review of neuropsychological studies

We conducted a meta-analytic review of neuropsychological studies of mild head trauma (MHT). Studies were included if they met these criteria: patients studied at least 3 months after MHT; patients selected because of a history of MHT rather than because they were symptomatic; and attrition rate of less than 50% for longitudinal studies. Studies of children were not considered. We found a total of 8 published papers with 11 samples that met these criteria. Using the g statistics, the overall effect size of 0.07 was nonsignificant, but the d statistic yielded an effect size of 0.12, p < .03. Measurers of attention had the largest effect, g = 0.17. p < .02 and d = 0.20, p < .006. Severity of injury accounted for far more variance than did specific neuropsychological domain, however. The small effect size suggests that the maximum prevalence of persistent neuropsychological deficit is likely to be small and neuropsychological assessment is likely to have positive predictive value of less than 50%. Consequently, clinicians will more likely be correct when not diagnosing brain injury than when diagnosing a brain injury in cases with chronic disability after MHT.

Persisting symptoms after mild head injury: A review of the postconcussive syndrome

Seemingly mild head injuries frequently result in persisting postconcussive syndromes. The etiology of these symptoms is often controversial. Neuropsychological, neurophysiological, and neuropathological evidence that brain damage can occur in the absence of gross neurological deficits after mild injuries is reviewed. Direct impact to the head is not required to cause brain injury. Understandably, psychological factors also play a role in post-head-injury disability, but the effect of compensation claims and preinjury psychopathology is often secondary to organic factors. Persons over age 40 or with a history of previous head injury are more vulnerable to protracted symptomatology.

Assessment of malingering after mild head trauma with the portland digit recognition test

The Portland Digit Recognition Test (PDRT), a forced-choice measure of recognition memory designed for the purpose of assessing the possibility of malingering, was administered to two groups of clinically referred patients seeking financial compensation for injuries including a mild head trauma group and a brain dysfunction group and also to a third group with brain dysfunction not seeking compensation. The three groups were equated on verbal acquisition ability. The two groups seeking remuneration were impaired on the PDRT compared with the group not seeking compensation, and the brain dysfunction group seeking compensation was superior to the mild head trauma group. Cut-off scores were established for the group with brain dysfunction not seeking compensation, and 33% of the mild head trauma group and 18% of the brain dysfunction group seeking compensation fell below the cut-offs. Significantly below chance scores were found in 17% and 3% of the two groups seeking compensation, respectively. Difficult PDRT items were more sensitive than easy items to compensation-related deficit. The PDRT is recommended as a measure of exaggeration of memory deficits.

A review of mild head trauma. part II: Clinical implications

In Binder et al. (1997) a metal-analytic review revealed a small effect size attributable to a history of mild head trauma (MHT). The results suggested a weak association between MHT and persistent neuropsychological deficits. In this paper, additional outcome data are summarized and the results are discussed. On a chronic basis, 7-8% of MHT patients remain symptomatic and 14% are disabled from work. Magnetic resonance studies of acutely injured persons may show lesions that are not detected in usual clinical practice. It is likely that the effects of these lesions dissipate with time, consistent with the neuropsychological data. The association between MHT and cognitive deficits, symptoms, and disability may not be casual; data suggest that MHT patients have more psychosocial problems prior to injury than do non-injured persons. The examiner of the MHT patient with chronic complaints must consider alternative medical and psychiatric explanations and perform a differential diagnosis. The possibility of a neurological basis for sustained neuropsychological problems cannot be completely dismissed. Presently, however, there is little evidence for neurological causation of most persisting complaints.

Money matters: A meta-analytic review of the association between financial compensation and the experience and treatment of chronic pain.

Meta-analytic procedures were used to determine the relation between disability compensation and pain. Of the 157 relevant identified studies, only 32 contained quantifiable data from treatment and control groups. The majority of these exclusively examined chronic low back pain patients (72%). Overall, 136 comparisons were obtained, on the basis of 3,802 pain patients and 3,849 controls. Liberal procedures for estimating effect sizes (ESs) yielded an ES of .60 (p < .0002). Conservative procedures yielded an ES of .48 (p < .0005). Both ESs differed from zero, indicating that compensation is related to increased reports of pain and decreased treatment efficacy. These results are interpreted in light of current models of pain. Health policy implications are also discussed.

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.

Detecting exaggeration and malingering in neuropsychological assessment.

&NA; Magnification of symptoms or nonoptimal effort on neuropsychological tests, within the context of head injury litigation, can have several independent or related underlying causes. Therefore, detecting exaggeration does not automatically indicate that the individual is malingering. This article reviews the evaluative and differential diagnostic process and provides the clinician with suggestions regarding assessment methods. A forensic evaluation that does not include careful consideration of possible negative response bias should be considered incomplete.

Malingering following Minor head trauma

The possibility of malingering should be considered whenever an opportunity for financial gain exists or when the subjective complaints outweigh the objective findings. Minor-head-injury patients often meet one or both of these criteria. Four cases of probable malingering and one case of possible malingering after minor head injury are discussed. Observations of untruthfulness, test abnormalities more severe than predicted by knowledge of the injury, bizarre results on Face-Hand (Double Simultaneous Stimulation) testing, and especially forced-choice testing of memory complaints provided useful diagnostic data in these cases. Performance on a forced-choice technique that is significantly worse than chance is presumed to result from the deliberate production of wrong answers. An improved method of forced-choice testing based on work by Hiscock and Hiscock (in press) is presented.

Constructional strategies on complex figure drawings after unilateral brain damage

The strategy used in drawing a complex geometric design was compared in right-brain-damaged (RBD) and left-brain-damaged (LBD) stroke patients and normals. A record of the sequence of line segments used to copy the design was obtained. Normals drew elements of the figure as one unit, while LBD patients broke these elements into more than one unit. The unusual sequencing and fragmented, piecemeal approach of the LBD group was sometimes associated with a delay in attention to the right side, but did not necessarily lead to an impaired finished copy. As expected, the RBD distortions were more severe. It is concluded that an intact right hemisphere does not ensure a holistic approach to copying complex geometric figures.

Neuropsychological evidence of a factitious memory complaint

The authors describe a patient who complained of a severe memory loss. Information gathered from the history, interview, and testing suggested malingering. The patient was then assessed by a strategy called Symptom Validity Testing. Her score was statistically worse than chance, which provided compelling evidence that she was faking bad.