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There is increasing awareness of the need to use Performance Validity Tests (PVTs) when assessing cognitive abilities in children. Since 1996, there has been an ongoing clinical study of the use of three PVTs with a consecutive series of 1,285 developmentally disabled children. In this study, we report on the results of these PVTs in children of many diagnostic categories. Failure rates on all three tests were very low. The mean scores on the effort measures in those passing the PVTs were extremely high. Failure on each PVT was found to be associated with a significant and widespread suppression of scores across a neuropsychological battery. Failure on even one PVT significantly suppresses ability test scores.

Objective: To replicate previous research on Conners' Continuous Performance Test - Second Edition subscales as performance validity tests (PVTs) in children., Method: Classification accuracy for the Omissions (OMI), Hit Reaction Time (HRT), and Perseverations (PER) subscales was computed for 414 children and adolescents., Results: Overall, OMI, HRT, and PER demonstrated good specificity but low and variable sensitivity across cutoffs., Conclusions: Results suggest that OMI, HRT, and PER can function as embedded PVTs in mixed clinical samples of children, although their clinical utility is limited by their low sensitivity. Implications for the use of these PVTs in the context of attention-deficit/hyperactivity disorder evaluations, medication-seeking patients, and sports concussion clinics are discussed.

Past studies have examined the ability of the Wisconsin Card Sorting Test (WCST) to discriminate valid from invalid performance in adults using both individual embedded validity indicators (EVIs) and multivariate approaches. This study is designed to investigate whether the two most stable of these indicators-failures to maintain set (FMS) and the logistical regression equation S-B LRE -can be extended to pediatric populations. The classification accuracy for FMS and S-B LRE was examined in a mixed clinical sample of 226 children aged 7 to 17 years (64.6% male, MAge = 13.6 years) against a combination of established performance validity tests (PVTs). The results show that at adult cutoffs, FMS and S-B LRE produce an unacceptably high failure rate (33.2% and 45.6%) and low specificity (.55-.72), but an upward adjustment in cutoffs significantly improves classification accuracy. Defining Pass as <2 and Fail as ≥4 on FMS results in consistently good specificity (.89-.92) but low and variable sensitivity (.00-.33). Similarly, cutting the S-B LRE distribution at 3.68 produces good specificity (.90-.92) but variable sensitivity (.06-.38). Passing or failing FMS or S-B LRE is unrelated to age, gender and IQ. The data from this study suggest that in a pediatric sample, adjusted cutoffs on the FMS and S-B LRE ensure good specificity, but with low or variable sensitivity. Thus, they should not be used in isolation to determine the credibility of a response set. At the same time, they can make valuable contributions to pediatric neuropsychology by providing empirically-supported, expedient and cost-effective indicators to enhance performance validity assessment.

In previous research, several subscales of Conners' CPT-II were found to be useful as performance validity tests (PVTs) when administered to adults with traumatic brain injury (TBI). Furthermore, invalid response sets were associated with inflated scores on several CPT-II scales. The present study proposed to investigate whether these findings would replicate in a pediatric sample. The analyses were based on archival data from 15 children with TBI. The Omissions, Hit RT, Perseverations, and Hit RT BC scales proved effective at differentiating valid and invalid response sets. However, Commission errors were unrelated to scores on PVTs. A composite measure based on these four scores was a superior and more stable validity indicator than individual scales. Two or more T-scores >65 on any of these scales resulted in acceptable overall specificity (.86-1.00) and variable sensitivity (.00-1.00). Scores on CPT-II scales were generally higher among those who failed the reference PVTs. Results suggest that embedded CPT-II validity indices developed in adult TBI samples function similarly in children with TBI, with some notable exceptions. Although the use of adult PVT cutoffs in pediatric assessment is a common practice, and broadly supported by the present findings, there remains a clear need for the independent empirical validation of adult PVTs in children.

Aboriginal children in Canada are at high risk of fetal alcohol spectrum disorder (FASD) but there is little research on the cognitive impact of prenatal alcohol exposure (PAE) in this population. This paper reviews the literature on parent report of executive functioning in children with FASD that used the Behavior Rating Inventory of Executive Function (BRIEF). New data on the BRIEF is then reported in a sample of 52 Aboriginal Canadian children with FASD for whom a primary caregiver completed the BRIEF. The children also completed a battery of neuropsychological tests. The results reveal mean scores in the impaired range for all three BRIEF index scores and seven of the eight scales, with the greatest difficulties found on the Working Memory, Inhibit and Shift scales. The majority of the children were reported as impaired on the index scores and scales, with Working Memory being most commonly impaired scale. On the performance-based tests, Trails B and Letter Fluency are most often reported as impaired, though the prevalence of impairment is greater for parent ratings than test performance. No gender difference is noted for the parent report, but the boys had slightly slower intellectual functioning and were more perseverative than the girls on testing. The presence of psychiatric comorbidity is unrelated to either BRIEF or test scores. These findings are generally consistent with prior studies indicating that parents observe considerable executive dysfunction in children with FASD, and that children with FASD may have more difficulty with executive functions in everyday life than is detected by laboratory-based tests alone.

If we wish to conclude that failure on a performance validity test (PVT) is a false positive for poor effort, we must have evidence that the person is truly incapable of passing the test because of cognitive impairment. We must show that they have a diagnostic condition that is sufficient to account fully for failure on that test. The purpose of the current study was to evaluate the performance of children with a primary diagnosis of intellectual disability (ID) on the Word Memory Test (WMT), the Medical Symptom Validity Test (MSVT), and the Nonverbal Medical Symptom Validity Test (Green, 2003 , 2004 , 2008b ; Green & Astner, 1995 ). If a Full-Scale IQ (FSIQ) less than 70 could account for failure on these tests in adults, then children with ID would also fail them. In fact, the children with ID in the current study did not fail the WMT or MSVT as long as they had at least a Grade 3 reading level. Also, the children with ID did not fail these tests any more often than did children of significantly higher intelligence. The data suggest that an FSIQ in the range of 48 to 70 is not sufficient to explain failure on these PVTs by children or adults.

Previous studies of performance on the Word Memory Test (WMT; Green, 2003 ; Green & Astner, 1995 ) in adults with very low intelligence have provided conflicting evidence. Most studies suggest that a Full-Scale IQ (FSIQ) less than 70 cannot explain failure on the WMT, but Shandera et al. ( 2010 ) suggest that many adults with mental retardation (MR) cannot pass the WMT. If so, we would expect adults with such low intelligence to fail the WMT at a high rate, even if they were motivated to perform well. In the current study, parents with an FSIQ of 70 or less, who were seeking custody of their children, rarely failed the WMT or the Medical Symptom Validity Test (MSVT; Green, 2004 ). They did not fail the WMT or MSVT any more often than adults of higher intelligence. On the other hand, adults with an external incentive to appear impaired scored significantly lower on the WMT and MSVT than did parents with an incentive to look good. The data strongly suggest that MR with an FSIQ in the range of 46 to 70 is not sufficient to explain failure on these performance validity tests by adults.

The present study assessed performance on symptom validity tests (SVTs) and various cognitive-processing measures to evaluate the impact of having attention-deficit hyperactivity disorder (ADHD) on SVT performance using a clinical sample of 73 children aged 7 to 18 years old who had a previous diagnosis of ADHD. Cognitive impairment associated with ADHD may lead these individuals to perform poorly on what are considered to be relatively easy but boring SVTs. Few clients in this sample returned a score pattern on the Word Memory Test, Medical Symptom Validity Test, or Nonverbal Medical Symptom Validity Test that would have classified them as having invested poor effort; the Computerized Assessment of Response Bias returned higher rates of failure. In the absence of a lifelong history of severe attention and impulse control problems, and especially where secondary gains exist for obtaining a diagnosis, clinicians should interpret low scores on these SVTs as indicating low effort or noncredible performance as opposed to failure due to the symptoms of ADHD.

Primary Objective: Motivation has an important influence on neuropsychological test performances. This study examined effort on the Word Memory Test (WMT) in groups with differing external incentives., Research Design: 774 adults with Traumatic Brain Injury (TBI), tested as part of a Workers' Compensation, disability or personal injury claim stood to gain financially by appearing impaired on testing. In contrast, parents ordered by the Court to undergo a parenting assessment were highly motivated to do their best on cognitive tests because their goal was to regain custody of their children., Outcomes and Results: Consistent with these assumptions, 98.3% of 118 parents seeking child custody passed the WMT effort subtests but in cases of mild TBI the pass rate on the WMT was only 60%. The WMT failure rate in the mild TBI sample was 23 times higher than in the group of parents seeking custody. WMT failure was twice as frequent in the mild TBI group than in those with more severe TBI. WMT failure was also much higher in adults with mild TBI than in children with significant impairment from various clinical conditions., Conclusions: Such differences in failure rates on the WMT effort subtests cannot be explained by differences in cognitive skills but they are explainable by differences in external incentives. The findings support the recommendation that objective tests of effort should be used when evaluating cognitive impairment.

One-hundred and thirty-five children between the ages of 7 and 18 years were evaluated clinically. Their diagnoses included Fetal Alcohol Syndrome (FAS) or Effects, Schizophrenia, Bipolar Mood Disorder, various neurological diseases, Attention Deficit Hyperactivity Disorder (ADHD), Conduct Disorder, Oppositional-Defiant Disorder and learning disabilities. As part of a comprehensive neuropsychological assessment, the children were given the Word Memory Test (WMT; Green, Allen, & Astner, 1996; Green & Astner, 1995), containing various subtests which measure, respectively, effort and verbal memory. Although age and verbal intelligence are known to affect scores on most ability tests, they were not found to be significant determinants of WMT effort scores. Younger children did not score any lower on the effort subtests than older children. The children scored as well as a group of parents seeking custody of their children and they scored higher than adult patients with mild head injuries. The computerized WMT requires some basic reading skills and some children with lower than a grade 3 reading level scored at a relatively low level on the effort subtests. The current data suggest that most children with at least a grade 3 reading level can pass the WMT using the adult criteria. It is concluded that the WMT is potentially useful in the evaluation of effort during pediatric neuropsychological evaluations. Further research is needed to replicate these findings and to develop child norms for the memory subtests.