Victoria Symptom Validity Test: A Systematic Review and Cross-Validation Study.

Abstract

The Victoria Symptom Validity Test (VSVT) is a performance validity test (PVT) with over two decades of empirical backing, although methodological limitations within the extant literature restrict its clinical and research generalizability. Chief among these constraints includes limited consensus on the most accurate index within the VSVT and the most appropriate cut-scores within each VSVT validity index. The current systematic review synthesizes existing VSVT validation studies and provides additional cross-validation in an independent sample using a known-groups design. We completed a systematic search of the literature, identifying 17 peer-reviewed studies for synthesis (7 simulation designs, 7 differential prevalence designs, and 3 known-groups designs). The independent cross-validation sample consisted of 200 mixed clinical neuropsychiatric patients referred for outpatient neuropsychological evaluation. Across all indices, Total item accuracy produced the strongest psychometric properties at an optimal cut-score of ≤ 40 (62% sensitivity/88% specificity). However, ROC curve analyses for all VSVT indices yielded statistically significant areas under the curve (AUCs; .73-81), suggestive of moderate classification accuracy. Cut-scores derived using the independent cross-validation sample converged with some previous findings supporting cut-scores of ≤ 22 for Easy item accuracy and ≤ 40 for Total item accuracy, although divergent findings were noted for Difficult item accuracy. Overall, VSVT validity indicators have adequate diagnostic accuracy across populations, with the current study providing additional support for its use as a psychometrically sound PVT in clinical settings. However, caution is recommended among patients with certain verified clinical conditions (e.g., dementia) and those with pronounced working memory deficits due to concerns for increased risk of false positives.