Assessing performance validity during attention-deficit/hyperactivity disorder evaluations: Cross-validation of non-memory embedded validity indicators.

Embedded performance validity tests (PVTs) are key components of neuropsychological evaluations. However, most are memory-based and may be less useful in the assessment of attention-deficit/hyperactivity disorder (ADHD). Four non-memory-based validity indices derived from processing speed and executive functioning measures commonly included in ADHD evaluations, namely Verbal Fluency (VF) and the Trail Making Test (TMT), were cross-validated using the Rey 15-Item Test (RFIT) Recall and Recall/Recognition as memory-based comparison measures. This consecutive case series included data from 416 demographically-diverse adults who underwent outpatient neuropsychological evaluation for ADHD. Validity classifications were established, with ≤1 PVT failure of five independent criterion PVTs as indicative of valid performance (374 valid performers/42 invalid performers). Among the statistically significant validity indicators, TMT-A and TMT-B T-scores (AUCs = .707-.723) had acceptable classification accuracy ranges and sensitivities ranging from 29%-36% (≥89% specificity). RFIT Recall/Recognition produced similar results as TMT-B T-score with 42% sensitivity/90% specificity, but with lower classification accuracy. In evaluating adult ADHD, VF and TMT embedded PVTs demonstrated comparable sensitivity and specificity values to those found in other clinical populations but necessitated alternate cut-scores. Results also support use of RFIT Recall/Recognition over the standard RFIT Recall as a PVT for adult ADHD evaluations.

Examining Traditional and Novel Validity Indicators from the Medical Symptom Validity Test Across Levels of Verbal and Visual Memory Impairment.

OBJECTIVE: This cross-sectional study examined accuracy of traditional Medical Symptom Validity Test (MSVT) validity indicators, including immediate recognition (IR), delayed recognition (DR), and consistency (CNS), as well as a novel indicator derived from the mean performance on IR, DR, and CNS across verbal, visual, and combined learning and memory impairment bands. METHOD: A sample of 180 adult outpatients was divided into valid (n = 150) and invalid (n = 30) groups based on results of four independent criterion performance validity tests. Verbal and visual learning and recall were classified as indicative of no impairment, mild impairment, or severe impairment based on performance on the Rey Auditory Verbal Learning Test and Brief Visuospatial Memory Test-Revised, respectively. RESULTS: In general, individual MSVT subtests were able to accurately classify performance as valid or invalid, even in the context of severe learning and memory deficits. However, as verbal and visual memory impairment increased, optimal MSVT cut-scores diverged from manual-specified cutoffs such that DR and CNS required cut-scores to be lowered to maintain adequate specificity. By contrast, the newly proposed scoring algorithm generally showed more robust psychometric properties across the memory impairment bands. CONCLUSIONS: The mean performance index, a novel scoring algorithm using the mean of the three primary MSVT subtests, may be a more robust validity indicator than the individual MSVT subtests in the context of bona fide memory impairment.