Forensic Prediction of Malingering from Performance Validity Tests: Review of Leonhard (2023, a, b, c)

In a series of articles in 2023, Leonhard has presented criticisms of extant approaches to the use and interpretation of performance validity tests (PVTs) in malingering determinations in neuropsychological assessments. This paper reviews the relevant details of the articles relevant commentary. In the first article, Leonard describes statistical issues. In the second, he moves on to methodological ones. His third article responds to commentaries on the first two articles. The fourth article gives implications for court, and whether standard approaches to the use of PVTs in malingering determinations meet expected scientific standards according to the SCOTUS decision of Daubert. Among the criticisms he raises, he queries: (a) whether PVTs are independent, in that they are too collinear; (b) classificatory algorithms do not use all relevant statistics; (c) the studies in the field do not typically present confidence intervals; (d) the studies on the validity of available PVTs are circular because they typically use PVTs to define malingering status; (e) classification accuracy statistics are overinflated by typically excluding indeterminate cases; and (f) validation studies reflect a high risk of bias, as demonstrated for one PVT reviewed. Both Leonhard and the present article call for more research on these questions.