Base rates of invalidity when patients undergoing routine clinical evaluations have social security disability as an external incentive.

Objective: Social Security Disability is a common external incentive in neuropsychological evaluations. This study determined base rates of invalidity when patients referred for routine clinical evaluations have Social Security Disability as an external incentive. Method: Patients (n = 242) were grouped as validly or invalidly performing based on the use of multiple performance validity tests. Frequency analyses were then conducted. Results: As a whole, 46.0% of clinically referred patients with Social Security Disability as an external incentive produced invalid data. When divided by disability pursuit status, 58.6% of individuals already receiving Social Security Disability, 44.6% of individuals actively seeking Social Security Disability, and 39.3% of individuals considering seeking Social Security Disability produced invalid data. By comparison, only 8.5% of clinically referred patients without known external incentives produced invalid data. Conclusions: Beyond establishing base rates, these data indicate that the external incentive, not necessarily the evaluation setting, increases the rate of invalidity, as obtained base rates mirror those observed in independent medical examinations. In addition, this study highlights that even patients who report that they are considering but have not committed themselves to pursuing an external incentive frequently invalidate testing.

A Systematic Review and Meta-Analysis of the Utility of the Test of Memory Malingering in Pediatric Examinees.

OBJECTIVE: This is the first systematic review and meta-analysis of the Test of Memory Malingering (TOMM) in pediatric examinees. It adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. METHOD: A systematic literature search was conducted using PsycINFO and PubMed, reviewing articles from January 1997 to July 2019. Books providing data on pediatric validity testing were also reviewed for references to relevant articles. Eligibility criteria included publication in a peer-reviewed journal, utilizing a pediatric sample, providing sufficient data to calculate specificity and/or sensitivity, and providing a means for evaluating validity status external to the TOMM. After selection criteria were applied, 9 articles remained for meta-analysis. Samples included clinical patients and healthy children recruited for research purposes; ages ranged from 5 to 18. Fixed and random effects models were used to calculate classification accuracy statistics. RESULTS: Traditional adult-derived cutoffs for Trial 2 and Retention were highly specific (0.96-0.99) in pediatric examinees for both clinical and research samples. Sensitivity was relatively strong (0.68-0.70), although only two studies reported sensitivity rates. A supplemental review of the literature corroborated these findings, revealing that traditional adult-based TOMM cutoffs are supported in most pediatric settings. However, limited research exists on the impact of very young age, extremely low cognitive functioning, and varying clinical diagnoses. CONCLUSIONS: The TOMM, at traditional adult cutoffs, has strong specificity as a performance validity test in pediatric neuropsychological evaluations. This meta-analysis found that specificity values in children are comparable to those of adults. Areas for further research are discussed.

Functional integration of acute myeloid leukemia into the vascular niche.

Vascular endothelial cells are a critical component of the hematopoietic microenvironment that regulates blood cell production. Recent studies suggest the existence of functional cross-talk between hematologic malignancies and vascular endothelium. Here we show that human acute myeloid leukemia (AML) localizes to the vasculature in both patients and in a xenograft model. A significant number of vascular tissue-associated AML cells (V-AML) integrate into vasculature in vivo and can fuse with endothelial cells. V-AML cells acquire several endothelial cell-like characteristics, including the upregulation of CD105, a receptor associated with activated endothelium. Remarkably, endothelial-integrated V-AML shows an almost fourfold reduction in proliferative activity compared with non-vascular-associated AML. Primary AML cells can be induced to downregulate the expression of their hematopoietic markers in vitro and differentiate into phenotypically and functionally defined endothelial-like cells. After transplantation, these leukemia-derived endothelial cells are capable of giving rise to AML. These novel functional interactions between AML cells and normal endothelium along with the reversible endothelial cell potential of AML suggest that vascular endothelium may serve as a previously unrecognized reservoir for AML.