This study was designed to examine the effect of various criterion measures on the classification accuracy of Trial 1 of the Test of Memory Malingering (TOMM-1), a free-standing performance validity test (PVT). Archival data were collected from a case sequence of 91 (M Age = 42.2 years; M Education = 12.7) patients clinically referred for neuropsychological assessment. Trials 2 and Retention of the TOMM, the Word Choice Test, and three validity composites were used as criterion PVTs. Classification accuracy varied systematically as a function of criterion PVT. TOMM-1 ≤ 43 emerged as the optimal cutoff, resulting in a wide range of sensitivity (.47-1.00), with perfect overall specificity. Failing the TOMM-1 was unrelated to age, education or gender, but was associated with elevated self-reported depression. Results support the utility of TOMM-1 as an independent, free-standing, single-trial PVT. Consistent with previous reports, the choice of criterion measure influences parameter estimates of the PVT being calibrated. The methodological implications of modality specificity to PVT research and clinical/forensic practice should be considered when evaluating cutoffs or interpreting scores in the failing range.
Keywords: Erdodi index; Test of Memory Malingering; modality specificity; multivariate models; performance validity.