Minimizing evaluation time while maintaining accuracy: Cross-validation of the Test of Memory Malingering (TOMM) Trial 1 and first 10-item errors as briefer performance validity tests.

Abstract

Current standards of practice in neuropsychology advocate for including validity tests (PVTs). Abbreviating PVTs, such as the Test of Memory Malingering (TOMM), may help reduce overall evaluation time while maintaining diagnostic accuracy. TOMM Trial 1 performance (T1), as well as the number of errors within the first 10 items of Trial 1 (TOMMe10), have shown initial promise as abbreviated PVTs but require additional external cross-validation. This study sought to replicate findings from other mixed, diverse, clinical samples and provide further validation of abbreviated administrations of the TOMM. Data included 120 veterans who completed the TOMM and 3 criterion PVTs during clinical evaluation. In total, performance from 68% of the sample was classified as valid (52% met criteria for cognitive impairment), and performance from 32% of the sample was invalid. Group differences, diagnostic accuracy statistics, and receiver operating characteristic (ROC) curves were analyzed for relevant TOMM indices. There were large (η²p= .45-.66), significant differences between validity groups (p < .001) on TOMM T1 and TOMMe10, with lower TOMM T1 and higher TOMMe10 scores for participants with invalid performance. Using established cut-scores, sensitivities/specificities were: TOMMe10 ≥1 error: .84/.66; ≥2 errors: .74/.93; TOMM T1 ≤40: .82/.93. ROC curve analysis yielded significant areas under the curve for both TOMMe10 and T1 with respective optimal cut-scores of ≥2 errors (.74 sensitivity/.93 specificity) and ≤41 (.84 sensitivity/.91 specificity). TOMMe10 and T1 performances are minimally impacted by cognitive impairment. Although both evidenced robust psychometric properties, TOMM T1 continued to show greater accuracy than TOMMe10. (PsycInfo Database Record (c) 2020 APA, all rights reserved).