Are there differences in performance validity test scores between African American and White American neuropsychology clinic patients?

OBJECTIVE: The purpose of the present study was to compare performance on a wide range of PVTs in a neuropsychology clinic sample of African Americans and White Americans to determine if there are differences in mean scores or cut-off failure rates between the two groups, and to identify factors that may account for false positive PVT results in African American patients. METHOD: African American and White American non-compensation-seeking neuropsychology clinic patients were compared on a wide range of standalone and embedded PVTs: Dot Counting Test, b Test, Warrington Recognition Memory Test, Rey 15-item plus recognition, Rey Word Recognition Test, Digit Span (ACSS, RDS, 3-digit time, 4-digit time), WAIS-III Picture Completion (Most discrepant index), WAIS-III Digit Symbol/Coding (recognition equation), Rey Auditory Verbal Learning Test, Rey Complex figure, WMS-III Logical Memory, Comalli Stroop Test, Trails A, and Wisconsin Card Sorting Test. RESULTS: When groups were equated for age and education, African Americans obtained mean performances significantly worse than White Americans on only four of 25 PVT scores across the 14 different measures (Stroop Word Reading and Color Naming, Trails A, Digit Span 3-digit time); however, FSIQ was also significantly higher in White American patients. When subjects with borderline IQ (FSIQ = 70 to 79) were excluded (resulting in 74 White Americans and 25 African Americans), groups no longer differed in IQ and only continued to differ on a single PVT cutoff (Trails A). Further, specificity rates in African Americans were comparable to those of White Americans with the exception of the b Test, the Dot Counting Test, and Stroop B. CONCLUSIONS: PVT performance generally does not differ as a function of Black versus White race once the impact of intellectual level is controlled, and most PVT cutoffs appear appropriate for use in African Americans of low average IQ or higher.

Wait, There's a Baby in this Bath Water! Update on Quantitative and Qualitative Cut-Offs for Rey 15-Item Recall and Recognition.

OBJECTIVE: Evaluate the effectiveness of Rey 15-item plus recognition data in a large neuropsychological sample. METHOD: Rey 15-item plus recognition scores were compared in credible (n = 138) and noncredible (n = 353) neuropsychology referrals. RESULTS: Noncredible patients scored significantly worse than credible patients on all Rey 15-item plus recognition scores. When cut-offs were selected to maintain at least 89.9% specificity, cut-offs could be made more stringent, with the highest sensitivity found for recognition correct (cut-off ≤11; 62.6% sensitivity) and the combination score (recall + recognition - false positives; cut-off ≤22; 60.6% sensitivity), followed by recall correct (cut-off ≤11; 49.3% sensitivity), and recognition false positive errors (≥3; 17.9% sensitivity). A cut-off of ≥4 applied to a summed qualitative error score for the recall trial resulted in 19.4% sensitivity. Approximately 10% of credible subjects failed either recall correct or recognition correct, whereas two-thirds of noncredible patients (67.7%) showed this pattern. Thirteen percent of credible patients failed either recall correct, recognition correct, or the recall qualitative error score, whereas nearly 70% of noncredible patients failed at least one of the three. Some individual qualitative recognition errors had low false positive rates (<2%) indicating that their presence was virtually pathognomonic for noncredible performance. Older age (>50) and IQ < 80 were associated with increased false positive rates in credible patients. CONCLUSIONS: Data on a larger sample than that available in the 2002 validation study show that Rey 15-item plus recognition cut-offs can be made more stringent, and thereby detect up to 70% of noncredible test takers, but the test should be used cautiously in older individuals and in individuals with lowered IQ.

Examination of the Modified Somatic Perception Questionnaire (MSPQ) in a large sample of credible and noncredible patients referred for neuropsychological testing.

OBJECTIVE: The current study evaluated MSPQ sensitivity to noncredible PVT performance in the context of external incentive, and examined MSPQ false positive rates in noncompensation-seeking neuropsychology patients; and investigated effects of ethnicity/culture, gender, and somatoform diagnosis on MSPQ scores, and relationships with PVT and MMPI-2-RF data. METHOD: MSPQ scores were compared in credible (n = 110) and noncredible (n = 153) neuropsychology referrals. RESULTS: Noncredible patients scored higher than credible patients. When the credible group was divided into those with somatoform orientation (n = 39) versus those without (n = 71), the credible nonsomatoform group scored lower than the other two groups, who did not differ from each other. MSPQ elevations were found in ethnic minorities, and in individuals who learned English as a second language or concurrently with another language. MSPQ elevations were also associated with chronic systemic diseases, neurologic illness, and substance abuse. Women scored higher than men, but men and women were equally represented among those patients scoring beyond cut-offs. MSPQ scores were minimally related to PVT data but were more strongly correlated with MMPI-2-RF scales, particularly over-report validity scales, RC1, and Somatic/Cognitive scales, with more widespread relationships observed in noncredible patients. CONCLUSIONS: A cut-off of 18 resulted in few false positives in credible nonsomatoform patients, and appears appropriate for identifying physical symptom over-report (due to malingering or somatoform orientations), with associated sensitivity of 29%. However, clinicians are cautioned regarding using the MSPQ in patients with systemic, neurologic, and substance abuse conditions, and in ethnic minorities and non-monolingual English-speakers.

Comparison of credible patients of very low intelligence and non-credible patients on neurocognitive performance validity indicators.

The purpose of this archival study was to identify performance validity tests (PVTs) and standard IQ and neurocognitive test scores, which singly or in combination, differentiate credible patients of low IQ (FSIQ ≤ 75; n = 55) from non-credible patients. We compared the credible participants against a sample of 74 non-credible patients who appeared to have been attempting to feign low intelligence specifically (FSIQ ≤ 75), as well as a larger non-credible sample (n = 383) unselected for IQ. The entire non-credible group scored significantly higher than the credible participants on measures of verbal crystallized intelligence/semantic memory and manipulation of overlearned information, while the credible group performed significantly better on many processing speed and memory tests. Additionally, credible women showed faster finger-tapping speeds than non-credible women. The credible group also scored significantly higher than the non-credible subgroup with low IQ scores on measures of attention, visual perceptual/spatial tasks, processing speed, verbal learning/list learning, and visual memory, and credible women continued to outperform non-credible women on finger tapping. When cut-offs were selected to maintain approximately 90% specificity in the credible group, sensitivity rates were highest for verbal and visual memory measures (i.e., TOMM trials 1 and 2; Warrington Words correct and time; Rey Word Recognition Test total; RAVLT Effort Equation, Trial 5, total across learning trials, short delay, recognition, and RAVLT/RO discriminant function; and Digit Symbol recognition), followed by select attentional PVT scores (i.e., b Test omissions and time to recite four digits forward). When failure rates were tabulated across seven most sensitive scores, a cut-off of ≥ 2 failures was associated with 85.4% specificity and 85.7% sensitivity, while a cut-off of ≥ 3 failures resulted in 95.1% specificity and 66.0% sensitivity. Results are discussed in light of extant literature and directions for future research.

Cross validation of the b Test in a large known groups sample.

The b Test (Boone, Lu, & Herzberg, 2002a) is a measure of cognitive performance validity originally validated on 91 non-credible participants and 7 credible clinical comparison groups (total n = 161). The purpose of the current study was to provide cross-validation data for the b Test on a known groups sample of non-credible participants (n = 212) and credible heterogeneous neuropsychological clinic patients (n = 103). The new data showed that while the original E-score cut-off of ≥ 155 achieved excellent specificity (99%), it was associated with relatively poor sensitivity (41%). However, the cut-off could be substantially lowered to ≥82, while still maintaining adequate specificity (≥90%) and raising sensitivity to 68%. Examination of non-credible subgroups revealed that b Test sensitivity in feigned mild traumatic brain injury (mTBI) was 58%, whereas in non-credible patients claiming depression and psychosis, cut-off sensitivity was 76% and 67%, respectively. These data suggest that the b Test may have a particular role in detection of non-credible cognitive symptoms associated with feigned psychiatric symptoms, and that fabricated deficits in processing speed and vigilance/visual scanning, detected by the b Test, are more prominent in feigned psychiatric presentations than in feigned mTBI. Further, b Test failures in patients with somatoform disorders were common, indicating that the b Test may have a specific use in detection of non-consciously created cognitive dysfunction associated with somatoform conditions.

Re-examination of the Rey Word Recognition Test.

The Rey Word Recognition Test, a brief and simple to administer free-standing neurocognitive performance validity test, was examined in a large known-groups sample (122 credible patients and 134 non-credible patients). Total correctly recognized was the most sensitive score, identifying 54% of non-credible participants using a cut-off of ≤6, while maintaining specificity of approximately 90%. However, specifically rates were somewhat lower in credible individuals with <12 years of education or borderline intelligence, or who were bilingual (spoke English as a second language, or learned English concurrently with another language), indicating that cut-offs may require minor adjustment in these groups. Sensitivity rates were much higher in non-credible female versus male mild traumatic brain injury patients (mTBI; 68% versus 48% for total correct), suggesting that the Rey Word Recognition Test is particularly effective in identifying performance invalidity in female mTBI compensation seekers.

Use of the WAIS-III picture completion subtest as an embedded measure of response bias.

In the present study a large sample of credible patients (n = 172) scored significantly higher than a large sample of noncredible participants (n = 195) on several WAIS-III Picture Completion variables: Age Adjusted Scaled Score, raw score, a "Rarely Missed" index (the nine items least often missed by credible participants), a "Rarely Correct" index (nine items correct <26% of the time in noncredible participants and with at least a 25 percentage-point lower endorsement rate as compared to credible participants), and a "Most Discrepant" index (the six items that were the most discrepant in correct endorsement between groups-at least a 40 percentage point difference). Comparison of the various scores showed that the "Most Discrepant" index outperformed all the others in identifying response bias (nearly 65% sensitivity at 92.8% specificity as compared to at most 59% sensitivity for the other scores). While no differences in Picture Completion scores were observed between less-educated (<12 years) and better-educated (≥12 years) credible participants, noncredible participants with <12 years of education scored significantly poorer than noncredible participants with 12 or more years of education. On the "Most Discrepant" index, 76.7% of less-educated noncredible participants were detected as compared to 58.3% of better-educated noncredible participants. Results of the current study suggest that the Picture Completion subtest of the WAIS-III is an effective measure of response bias, and that it may have a unique role in identifying suboptimal effort in less-educated test takers.