What is a Neuropsychological Evaluation? – Part 3
Our previous posts in this serious have examined what a neuropsychological evaluation is and how these exams are conducted. In this post we’ll be talking about some of the limitations associated with these types of exams.
How Reliable Are Neuropsychological Evaluations?
As we explained in previous posts, neuropsychological evaluations seek to provide information about the brain and behavior through the use of established, standardized tests that produce quantitative data. This data can then be used to confirm and back up a subject’s reports of cognitive impairment.
These evaluations can serve several purposes, such as corroborating the cognitive effects of a disability, or outlining a subject’s limitations in his or her daily life (including the inability to return to one’s own occupation). For example, an evaluation might show that a dentist with a head injury has impaired motor skills and visuospatial processing abilities that make it unsafe for the dentist to continue treating patients. In this sense, an evaluation can provide data that can lend further support to a disability claim, but wouldn’t necessarily show up on an MRI or the results from other types of medical testing.
However, while these evaluations can be useful, they also have certain limitations that are important to consider. As with Functional Capacity Evaluations (FCEs) the examination is truly just a snapshot—the data is based on your functioning on a specific day, for a limited amount of time, in a quiet and controlled testing room.
Generally, findings indicate that performance on tests of motor function, speed of cognitive processing, cognitive flexibility, complex attention, and memory are related positively to real-word success. However, some argue that these exams do not adequately take into account the fact that, in the real world, several executive functions (such as recognizing a task must be completed, starting a task, switching tasks, making needed changes, finishing a task, etc.) can occur simultaneously. Further, the administered test may not indicate whether a subject was mentally exhausted after the test, and thus may not provide any insight into whether the subject is able to sustain the same demonstrated level of executive functioning day in and day out.
While the administered tests are designed to be objective and produce results that can be extrapolated across populations, this is not always possible. While a subject’s results should be compared with both population-based norms as well as specific patient populations for strengths and weaknesses, there can be gaps in normative data for certain age, educational, and intellectual ranges. This can be especially true for minority populations. Along these same lines, an evaluator may not take into account norms specific to doctors, or a doctor’s need for higher performance on certain tests (e.g. those for sensory-perceptual functions), when assessing whether a return to work is possible.
Excessive fatigue, medications, lack of motivation (sometimes due to depression), emotional distress, severe psychiatric conditions, serious medical complications, and illicit substances can also all impact the reliability of an evaluation.
Additionally, as we’ve discussed before in the context of Independent Medical Examinations (IMEs), a neuropsychological examiner selected by an insurance company may be presented as independent, but may not truly be so. An examiner selected and paid for by a disability insurer may be more likely to report that a subject is “malingering,” trying to influence a test’s outcome, or not putting forth a true effort.
In our next post, we will further explain why an insurer might require a neuropsychological evaluation, and how these exams can impact a disability claim.
 Atif B. Malike, MD; Chief Editor, et al., Neuropsychological Evaluation, Medscape, http://emedicine.medscape.com/article/317596-overview, updated May 18, 2017.
 Id. (citing Decker SL, Schneider WJ, Hale JB, Estimating Rates of Impairment in Neuropsychological Test Batters: A Comparison of Quantitative Models, Arch. Clin. Neuropsychol. 2011 Dec 15 [Medline].
Atif B. Malike, MD; Chief Editor, et al., Neuropsychological Evaluation, Medscape, http://emedicine.medscape.com/article/317596-overview, updated May 18, 2017.
Neuropsychological Evaluation FAQ, University of North Carolina School of Medicine Department of Neurology, https://www.med.unc.edu/neurology/divisions/movement-disorders/npsycheval
Kathryn Wilder Schaaf, PhD, et al, Frequently Asked Questions About Neuropsychological Evaluation, Virginia Commonwealth University Department of Physical Medicine and Rehabilitation, https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwir3pKk__fUAhUBEmMKHenkDzsQFggoMAA&url=http%3A%2F%2Fwww.tbinrc.com%2FWebsites%2Ftbinrcnew%2Fimages%2FNeuropsych_FAQ.pdf&usg=AFQjCNG0Mv3o17ZrNmXuDN5ITUIh4fWYtA&cad=rja