Base rate comparison of suboptimal scores on the RBANS effort scale and effort index in Parkinson’s disease

A Meta-Analysis of Neuropsychological Effort Test Performance in Psychotic Disorders

Psychotic disorders are characterized by a generalized neurocognitive deficit (i.e., performance 1.5 SD below controls across neuropsychological domains with no specific profile of differential deficits). A motivational account of the generalized neurocognitive deficit has been proposed, which attributes poor neuropsychological testing performance to low effort. However, findings are inconsistent regarding effort test failure rate in individuals with psychotic disorders across studies (0-72%), and moderators are unclear, making it difficult to know whether the motivational explanation is viable. To address these issues, a meta-analysis was performed on data from 2205 individuals with psychotic disorders across 19 studies with 24 independent effects. Effort failure rate was examined along with moderators of effort test type, forensic status, IQ, positive symptoms, negative symptoms, diagnosis, age, gender, education, and antipsychotic use. The pooled weighted effort test failure rate was 18% across studies and there was a moderate pooled association between effort failure rate and global neurocognitive performance (r = .57). IQ and education significantly moderated failure rate. Collectively, these findings suggest that a nontrivial proportion of individuals with a psychotic disorder fail effort testing, and failure rate is associated with global neuropsychological impairment. However, given that effort tests are not immune to the effects of IQ in psychotic disorders, these results cannot attest to the viability of the motivational account of the generalized neurocognitive deficit. Furthermore, the significant moderating effect of IQ and education on effort test performance suggests that effort tests have questionable validity in this population and should be interpreted with caution.

Performance Validity, Neurocognitive Disorder, and Post-concussion Symptom Reporting in Service Members with a History of Mild Traumatic Brain Injury

Objective

To examine the influence of different performance validity test (PVT) cutoffs on neuropsychological performance, post-concussion symptoms, and rates of neurocognitive disorder and postconcussional syndrome following mild traumatic brain injury (MTBI) in active duty service members.

Method

Participants were 164 service members (Age: M = 28.1 years [SD = 7.3]) evaluated on average 4.1 months (SD = 5.0) following injury. Participants were divided into three mutually exclusive groups using original and alternative cutoff scores on the Test of Memory Malingering (TOMM) and the Effort Index (EI) from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS): (a) PVT-Pass, n = 85; (b) Alternative PVT-Fail, n = 53; and (c) Original PVT-Fail, n = 26. Participants also completed the Neurobehavioral Symptom Inventory.

Results

The PVT-Pass group performed better on cognitive testing and reported fewer symptoms than the two PVT-Fail groups. The Original PVT-Fail group performed more poorly on cognitive testing and reported more symptoms than the Alternative PVT-Fail group. Both PVT-Fail groups were more likely to meet DSM-5 Category A criteria for mild and major neurocognitive disorder and symptom reporting criteria for postconcussional syndrome than the PVT-Pass group. When alternative PVT cutoffs were used instead of original PVT cutoffs, the number of participants with valid data meeting cognitive testing criteria for neurocognitive disorder or postconcussional syndrome decreased dramatically.

Conclusion

PVT performance is significantly and meaningfully related to overall neuropsychological outcome. By using only original cutoffs, clinicians and researchers may miss people with invalid performances.

A meta-analysis of the accuracy of embedded performance validity indicators from the repeatable battery for the assessment of neuropsychological status

Objective: Meta-analyze the embedded performance validity tests of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), emphasizing two topics: diagnostic accuracy and relationships with demographics. Method: Literature was identified through a review of PsycINFO, PubMed, and Google Scholar. Bivariate linear mixed models were used for diagnostic accuracy analyses. Random-effects analysis of correlations with demographic variables was also used for the Effort Index. Results: Diagnostic accuracy analyses utilized 12 studies of the Effort Index (EI; N = 1469) and 6 studies of the Effort Scale (ES; N = 854). The EI was found to have a sensitivity of .44 (95% CI: .28 - .62), specificity of .87 (95% CI: .78 - .93), and diagnostic odds ratio (DOR) of 5.41 (95% CI: 3.74 - 7.58). The ES produced a sensitivity of .67 (95% CI: .50 - .81), specificity of .72 (95% CI: .53 - .85), and DOR of 5.97 (95% CI: 1.70 - 15.30). Meta-analysis of correlations utilized 14 samples of the EI (N = 3781), but insufficient data were available for the ES. Correlations between the EI and age (r = .10, 95% CI: .05 - .16), education (r = -.11, 95% CI: -.18 to -.04), and the RBANS Total Scale (r = -.45, 95% CI: -.62 to -.24) were significant. These results appeared to be robust to publication bias. Conclusion: Results support use of the EI over the ES; however, the latter is comparatively less studied and did not have similar variability in reported cut-off scores. ES accuracy statistics were significantly predicted by sample variables, which may be related to its relatively fewer studies. Both measures should be used cautiously in the context of genuine cognitive impairment.