Are we documenting performance validity testing in pediatric neuropsychological assessments? A brief report

A comparison of MVP and MSVT performance among a diverse clinical pediatric sample

The Memory Validity Profile (MVP) and Medical Symptom Validity Test (MSVT) are performance validity tests (PVTs) used to identify potential noncredible test performance during psychological evaluations. This study sought to examine the agreement between MVP and MSVT pass rates, as well as to determine if there are differences in MVP pass rates when using the cutoff score in the MVP professional manual compared with the experimental cutoff score of <31. Via retrospective review of records, 106 clients at a private neuropsychological clinic who had been given the MVP and the MSVT were identified. Results indicated that only one client met the manual cutoff scores, compared to 20 clients who failed the MSVT, raising concerns regarding the sensitivity of the MVP. Utilizing the receiver operator characteristic (ROC), curve analyses indicated fair discriminability of the MVP for the 106 participants (AUC = .717) with acceptable sensitivity (.50) and specificity (.92) for an MVP total score cutoff of <31. These findings support the utility of the experimental cut score in improving the sensitivity while maintaining adequate specificity in a clinically mixed population.

Multivariate models provide an effective psychometric solution to the variability in classification accuracy of D-KEFS Stroop performance validity cutoffs

ObjectiveThe study was designed to expand on the results of previous investigations on the D-KEFS Stroop as a performance validity test (PVT), which produced diverging conclusions. Method The classification accuracy of previously proposed validity cutoffs on the D-KEFS Stroop was computed against four different criterion PVTs in two independent samples: patients with uncomplicated mild TBI (n = 68) and disability benefit applicants (n = 49). Results Age-corrected scaled scores (ACSSs) ≤6 on individual subtests often fell short of specificity standards. Making the cutoffs more conservative improved specificity, but at a significant cost to sensitivity. In contrast, multivariate models (≥3 failures at ACSS ≤6 or ≥2 failures at ACSS ≤5 on the four subtests) produced good combinations of sensitivity (.39-.79) and specificity (.85-1.00), correctly classifying 74.6-90.6% of the sample. A novel validity scale, the D-KEFS Stroop Index correctly classified between 78.7% and 93.3% of the sample. Conclusions A multivariate approach to performance validity assessment provides a methodological safeguard against sample- and instrument-specific fluctuations in classification accuracy, strikes a reasonable balance between sensitivity and specificity, and mitigates the invalid before impaired paradox.

Performance and Symptom Validity in Outpatient Pediatric Neuropsychological Evaluations

This study aimed to clarify the value of using different types of validity measures in pediatric neuropsychological evaluations. We examined the relationship between performance (PVT) and symptom (SVT) validity tests as well as demographic variables and results from a screening test of learning and memory (i.e. Child and Adolescent Memory Profile [ChAMP]) in a mixed pediatric sample (n = 103). There was minimal overlap between PVT and SVT failures. Regression analyses demonstrated that PVT results, parental education, and history of special education were statistically significant predictors of ChAMP results, whereas SVT results were not.

The Temporal Memory Sequence Test (TMST) in children: Validity test performance in clinically referred children

Validity evaluation is fundamental in neuropsychological assessment in adults, with increasing interest among pediatric neuropsychologists. Although some measures exist, given time constraints placed on clinicians, and children's limited sustained attention, development of less time-consuming measures is beneficial. We explored the use of the Temporal Memory Sequence Test (TMST), a new performance validity test, in clinically referred children. One minor adaptation included reading the instructions and labels to non-fluent readers. Participants were 68 consecutive clinically referred children and adolescents, aged 6-18 years, with neurological (n = 46) or behavioral (n = 22) difficulties. Applying the adult cutoff, 83.8% passed the TMST. Age, gender, and diagnosis did not differ between children passing the TMST cutoff and those who failed it. Classification accuracy calculated against three embedded measures of performance validity (Wechsler scale Digit Span, Coding, and Processing Speed Index) indicated specificity over 90% (Digit Span: 94%, Coding: 96%, Processing Speed Index: 92%) and sensitivity between 30 and 33%. For individuals without Intellectual Disability (ID), 90.9% passed the TMST, and intelligence did not predict success. Thus, the use of the TMST with the adult cutoff was supported in children without ID, offering an additional validity measure for clinically referred children.

Cross-Cultural Performance Validity Testing: Managing False Positives in Examinees with Limited English Proficiency

Base rates of failure (BR_Fail) on performance validity tests (PVTs) were examined in university students with limited English proficiency (LEP). BR_Fail was calculated for several free-standing and embedded PVTs. All free-standing PVTs and certain embedded indicators were robust to LEP. However, LEP was associated with unacceptably high BR_Fail (20-50%) on several embedded PVTs with high levels of verbal mediation (even multivariate models of PVT could not contain BR_Fail). In conclusion, failing free-standing/dedicated PVTs cannot be attributed to LEP. However, the elevated BR_Fail on several embedded PVTs in university students suggest an unacceptably high overall risk of false positives associated with LEP.

Critical Item Analysis Enhances the Classification Accuracy of the Logical Memory Recognition Trial as a Performance Validity Indicator

OBJECTIVE

: Replicate previous research on Logical Memory Recognition (LM_Recog) and perform a critical item analysis.

METHOD

: Performance validity was psychometrically operationalized in a mixed clinical sample of 213 adults. Classification of the LM_Recog and nine critical items (CR-9) was computed.

RESULTS

: LM_Recog ≤20 produced a good combination of sensitivity (.30-.35) and specificity (.89-.90). CR-9 ≥5 and ≥6 had comparable classification accuracy. CR-9 ≥5 increased sensitivity by 4% over LM_Recog ≤20; CR-9 ≥6 increased specificity by 6-8% over LM_Recog ≤20; CR-9 ≥7 increased specificity by 8-15%.

CONCLUSIONS

: Critical item analysis enhances the classification accuracy of the optimal LM_Recog cutoff (≤20).

Five shades of gray: Conceptual and methodological issues around multivariate models of performance validity

OBJECTIVE

This study was designed to empirically investigate the signal detection profile of various multivariate models of performance validity tests (MV-PVTs) and explore several contested assumptions underlying validity assessment in general and MV-PVTs specifically.

METHOD

Archival data were collected from 167 patients (52.4%male; MAge = 39.7) clinicially evaluated subsequent to a TBI. Performance validity was psychometrically defined using two free-standing PVTs and five composite measures, each based on five embedded PVTs.

RESULTS

MV-PVTs had superior classification accuracy compared to univariate cutoffs. The similarity between predictor and criterion PVTs influenced signal detection profiles. False positive rates (FPR) in MV-PVTs can be effectively controlled using more stringent multivariate cutoffs. In addition to Pass and Fail, Borderline is a legitimate third outcome of performance validity assessment. Failing memory-based PVTs was associated with elevated self-reported psychiatric symptoms.

CONCLUSIONS

Concerns about elevated FPR in MV-PVTs are unsubstantiated. In fact, MV-PVTs are psychometrically superior to individual components. Instrumentation artifacts are endemic to PVTs, and represent both a threat and an opportunity during the interpretation of a given neurocognitive profile. There is no such thing as too much information in performance validity assessment. Psychometric issues should be evaluated based on empirical, not theoretical models. As the number/severity of embedded PVT failures accumulates, assessors must consider the possibility of non-credible presentation and its clinical implications to neurorehabilitation.

The emotion word fluency test as an embedded performance validity indicator - Alone and in a multivariate validity composite

OBJECTIVE

This project was designed to cross-validate existing performance validity cutoffs embedded within measures of verbal fluency (FAS and animals) and develop new ones for the Emotion Word Fluency Test (EWFT), a novel measure of category fluency.

METHOD

The classification accuracy of the verbal fluency tests was examined in two samples (70 cognitively healthy university students and 52 clinical patients) against psychometrically defined criterion measures.

RESULTS

A demographically adjusted T-score of ≤31 on the FAS was specific (.88-.97) to noncredible responding in both samples. Animals T ≤ 29 achieved high specificity (.90-.93) among students at .27-.38 sensitivity. A more conservative cutoff (T ≤ 27) was needed in the patient sample for a similar combination of sensitivity (.24-.45) and specificity (.87-.93). An EWFT raw score ≤5 was highly specific (.94-.97) but insensitive (.10-.18) to invalid performance. Failing multiple cutoffs improved specificity (.90-1.00) at variable sensitivity (.19-.45).

CONCLUSIONS

Results help resolve the inconsistency in previous reports, and confirm the overall utility of existing verbal fluency tests as embedded validity indicators. Multivariate models of performance validity assessment are superior to single indicators. The clinical utility and limitations of the EWFT as a novel measure are discussed.

A comparison of the self-report patterns of analog versus real-world malingerers of attention deficit hyperactivity disorder

Much of what we know about malingering of attention deficit hyperactivity disorder (ADHD) has been learned from the performance of analog malingerers, typically first-year psychology students given credit for study participation. It is not clear, however, whether their performance is similar to that found in actual clinical settings. Indeed, past research suggests that analog malingerers may overexaggerate deficits relative to real-world malingerers, making them easier to identify in controlled studies. The purpose of the current study was, therefore, to compare the performance of analog malingers to post-secondary students strongly suspected of malingering ADHD on a self-report measure of ADHD symptoms. Their scores were, in turn, compared to those returned by students with genuine ADHD and clinical controls. Results demonstrated that, apart from analog subjects overexaggerating symptoms of hyperactivity, few differences exist between the scores returned by analog malingerers relative to clinical malingerers. While newly devised symptom validity measures show promise in identifying malingered ADHD, neither the analog nor the clinical malingers consistently failed these symptom validity scales. Furthermore, a good portion in both malingering groups failed to endorse high levels of ADHD symptoms in general. Clinical implications are discussed.

The use of the MSVT in children and adolescents with epilepsy

Pediatric neuropsychologists are increasingly recognizing the importance of performance validity testing during evaluations. The use of such measures to detect insufficient effort is of particular importance in pediatric epilepsy evaluations, where test results are often used to guide surgical decisions and failure to detect poor task engagement can result in postsurgical cognitive decline. The present investigation assesses the utility of the Medical Symptom Validity Test (MSVT) in 104 clinically referred children and adolescents with epilepsy. Though the overall failure rate was 15.4% of the total group, children with 2nd grade or higher reading skills (a requirement of the task) passed at a very high rate (96.6%). Of the three failures, two were unequivocally deemed true positives, while the third failed due to extreme somnolence during testing. Notably, for those with ≥2nd grade reading levels, MSVT validity indices were unrelated to patient age, intellectual functioning, or age of epilepsy onset, while modest relations were seen with specific memory measures, number of epilepsy medications, and seizure frequency. Despite these associations, however, this did not result in more failures in this population of children and adolescents with substantial neurologic involvement, as pass rates exceeded 92% for those with intellectual disability, high seizure frequency, high medication burden, and even prior surgical resection of critical memory structures.

They're not just little adults: The utility of adult performance validity measures in a mixed clinical pediatric sample

Performance validity tests (PVTs) have become a standard part of adult neuropsychological practice; however, they are less widely used in pediatric testing. The current study aimed to obtain a better understanding of the application of PVTs within a mixed clinical pediatric sample with a wide range of diagnosis, IQ, and age. Cross-sectional data were analyzed from 130 consecutive pediatric patients evaluated as part of clinical care and diagnosed with a variety of medical/neurological, developmental, and psychiatric disorders. Patients were administered a battery of neuropsychological tests; results of intellectual functioning measures (i.e., Wechsler Intelligence Scale for Children-Fifth Edition [WISC-V] or Wechsler Adult Intelligence Scale-Fourth Edition [WAIS-IV]), and PVTs (i.e., Test of Memory Malingering [TOMM] and Digit Span [DS] subtests of the WISC-V/WAIS-IV) were analyzed to assess PVT performance across the sample as well as age- and Full-Scale IQ-related (FSIQ) effects on pass rate. Results suggested that the TOMM is an effective validity test for youth, as the TOMM adult cutoff score was also valid for children (88% pass rate on TOMM trial 1 cut-score ≥41, 71% pass rate on TOMM trial 1 cut-score ≥45). In contrast, Reliable Digit Span (RDS) was less accurate (34% failed RDS [cut-score ≤6], 54% failed RDS-r [cut-score ≤10], and 25% failed DS ACSS [cut-score ≤5]) using standard adult cutoffs. Notably, although TOMM scores were not strongly influenced by IQ, DS scores increased as IQ increased. Overall, further analysis of PVTs can champion new standards of practice through additional research establishing PVT accuracy within pediatric populations.