80 Demographic Factors Affecting Sensitivity Rates of Performance Validity Tests in Spanish-Speaking Forensic Litigants.

Abstract

Objective:

This retrospective study compared base rates of failure on a series of standalone and embedded performance validity tests (PVTs) in a sample of Spanish-speaking forensic litigants and explored the impact of demographic factors on PVT performance.

Participants and Methods:

62 Spanish-speaking participants involved in litigation (primarily for work-related mTBI) underwent outpatient neuropsychological evaluation. Country of origin spanned South American (56.5%), Caribbean (22.5%), Central American (16.1%), North American (3.2%), and Spanish (1.6%) regions. Of this sample, 56 completed the Test of Memory Malingering (TOMM), 45 completed the Rey Fifteen Item Test (RFIT), and 49 completed the Dot Counting Test (DCT). Embedded validity measures, Reliable Digit Span (RDS) and the WHO-Auditory Verbal Learning Test (WHO-AVLT) were completed by 32 and 48 participants, respectively.

Results:

Effects of age (M=42.4, SD=11.72) and region of origin did not significantly impact overall performance on any measure. Mean scores across all standalone PVTs were below cutoffs, which have been previously suggested for use with Spanish-speaking populations (TOMM <40, RFIT total <21, DCT e-score >18). Overall base rates of failure were as follows: 52.5% TOMM (T1 M= 37.5, SD=10.7; T2 M=35.1, SD=10.6), 64.9% RFIT (M=17.8, SD=7.8) 57.6% DCT (M=18.3, SD=8.8), 51.1% RDS (M=6.1, SD=1.6), 29.4% WHO-AVLT (M=10.7, SD=3.9. Years of education (M=9.98, 3.96) was significantly correlated with RFIT total score (r(43) = .48, p<.01) and DCT e-score (r(47) = -.34, p<.05. When stratified by level of education (0-6, 7-11, and 12+), a large discrepancy in base rate of failure was observed on the RFIT, with failures in 92% of participants with less than six years of education, as compared to 52% and 59% failure in those with 7-11 and 12+ years, respectively. Variability in base rates of DCT failure across levels of education, although less extreme than on the RFIT, again demonstrated higher rates of failure in participants with less than six years of education (0-6: 71%, 7-11: 54%, 12+: 52%).

Conclusions:

These findings add to the existing literature surrounding measurement of suboptimal effort in Spanish-speaking populations. Base rates of PVT failure on both standalone and embedded measures were generally much higher than those reported in prior studies of forensic or compensation-seeking groups, including some with Spanish speaking participants. These high rates of failure are likely attributable, at least in part, to sample characteristics, due to the high proportion of individuals engaged in litigation associated with workplace injuries on construction sites at the study location. Such findings illustrate the importance of a thorough effort assessment for this population. Finally, results demonstrating reduced specificity of the RFIT in Spanish-speaking participants with less than six years of education, suggesting caution is warranted for its use in neuropsychological evaluations with such individuals.