A - 184 Validity of the Infrequent Patterns of Performance Embedded Performance Validity Indicators in a Mixed Clinical Sample.

OBJECTIVE: Novel performance validity tests (PVTs) for the Hopkins Verbal Learning Test-Revised (HVLT-R) and Brief Visuospatial Memory Test-Revised (BVMT-R), derived from infrequent patterns of performance (IPOP), were developed to examine invalid memory performance while reducing false positive misclassification. To examine their classification accuracy, these indicators were compared to several existing embedded PVTs in a mixed clinical sample.

METHOD: A chart review was completed for 75 adult outpatients (Mean Age = 52, Range = 19-85) referred to an academic medical center outpatient clinic for neuropsychological evaluation. Twenty-eight percent of the sample failed the Medical Symptom Validity Test (MSVT), which was used as the criterion to indicate invalid performance. Several established embedded validity indicators were calculated from HVLT-R and BVMT-R scores, including the recognition discrimination index (RDI) and percent retention (PR), as well as the Reliable Digit Span (RDS) validity indicator. Classification statistics, including sensitivity, specific, likelihood ratios, predictive values, and overall accuracy, were calculated and compared.

RESULTS: The HVLT-R IPOP had a higher overall classification accuracy (72%) compared to the RDI indicator (68%) while maintaining excellent specificity (97%). The BVMT-R IPOP had identical classification accuracy (75%) compared to the RDI and PR indicators with very high specificity (96%). Both indicators were more accurate than RDS (72%).

CONCLUSIONS: The HVLT-R and BVMT-R IPOP performance validity indicators produced adequate classification statistics when compared to existing embedded PVTs. Both indicators maintained excellent specificity, which is crucial in reducing false positive classification. Future research will focus on further examining the validity of these indicators in other clinical groups and known groups, including medico-legal populations.