Philip Dunbar-Mayer

Bio: Philip Dunbar-Mayer is an academic researcher from Argosy University, Seattle. The author has contributed to research in topics: Test validity & Psychometrics. The author has an hindex of 1, co-authored 1 publications receiving 33 citations.

Relationship between Tomm performance and PAI validity scales in a mixed clinical sample.

Abstract: This study addressed the relationship between Personality Assessment Inventory (PAI) validity indicators and cognitive effort measures on the Test of Memory Malingering (TOMM). Significant correlations were found between TOMM and some PAI validity scales. Factor analysis results found separate cognitive and personality components, but the Negative Impression Management (NIM) scale, a measure of response bias, had factor loadings on both the cognitive and the personality components. Follow-up hierarchical multiple regression and t-test analysis generally confirmed this result, and found that NIM and the Infrequency (INF) scale have significant relationships with the TOMM. The results indicate that individuals with elevations on the PAI's INF and NIM scales often display decreased cognitive effort on the TOMM. The current results support the hypothesis that personality assessment validity indicators have a modest but significant relationship with poor cognitive effort.

Influence of poor effort on self-reported symptoms and neurocognitive test performance following mild traumatic brain injury.

Abstract: When considering a diagnosis of postconcussion syndrome, clinicians must systematically evaluate and eliminate the possible contribution of many differential diagnoses, comorbidities, and factors that may cause or maintain self-reported symptoms long after mild traumatic brain injury (MTBI). One potentially significant contributing factor is symptom exaggeration. The purpose of the study is to examine the influence of poor effort on self-reported symptoms (postconcussion symptoms and cognitive complaints) and neurocognitive test performance following MTBI. The MTBI sample consisted of 63 referrals to a concussion clinic, evaluated within 5 months post injury (M = 2.0, SD = 1.0, range = 0.6-4.6), who were receiving financial compensation from the Workers' Compensation Board. Participants completed the Post-Concussion Scale (PCS), British Columbia Cognitive Complaints Inventory (BC-CCI), selected tests from the Neuropsychological Assessment Battery Screening Module (S-NAB), and the Test of Memory Malingering (TOMM). Participants were divided into two groups based on TOMM performance (15 fail, 48 pass). There were significant main effects and large effect sizes for the PCS (p = .002, d = 0.79) and BC-CCI (p = .011, d = 0.98) total scores. Patients in the TOMM fail group scored higher than those in the TOMM pass group on both measures. Similarly, there were significant main effects and/or large effect sizes on the S-NAB. Patients in the TOMM fail group performed more poorly on the Attention (p = .004, d = 1.26), Memory (p = .006, d = 1.16), and Executive Functioning (p > .05, d = 0.70) indexes. These results highlight the importance of considering the influence of poor effort, in conjunction with a growing list of factors that can influence, maintain, and/or mimic the persistent postconcussion syndrome.

Cognitive underperformance and symptom over-reporting in a mixed psychiatric sample.

Abstract: The current study examined the prevalence of cognitive underperformance and symptom over-reporting in a mixed sample of psychiatric patients (N = 183). We employed the Amsterdam Short-Term Memory Test (ASTM) to measure cognitive underperformance and the Structured Inventory of Malingered Symptomatology (SIMS) to measure the tendency to over-report symptoms. We also administered neuropsychological tests (e.g., Concept Shifting Task; Rey's Verbal Learning Test) and the Symptom Checklist-90 (SCL-90) to the patients. A total of 34% of them failed the ASTM, the SIMS or both tests. ASTM and SIMS scores were significantly, albeit modestly, correlated with each other (r = −.22). As to the links between underperformance, over-reporting, neuropsychological tasks, and the SCL-90, the association between over-reporting on the SIMS and SCL-90 scores was the most robust one. The subsample that only failed on the ASTM performed significantly worse on a compound index of memory performance. Our findings indicate that und...

Poor Performance Validity Predicts Clinical Characteristics and Cognitive Test Performance of OEF/OIF/OND Veterans in a Research Setting

Abstract: This study examined the performance of 198 Veteran research participants deployed during Operation Enduring Freedom, Operation Iraqi Freedom, and/or Operation New Dawn (OEF/OIF/OND) on four measures of performance validity: the Medical Symptom Validity Test (MSVT), California Verbal Learning Test: Forced Choice Recognition (FCR), Reliable Digit Span (RDS), and TOVA Symptom Exaggeration Index (SEI). Failure on these performance validity tests (PVTs) ranged from 4% to 9%. The overall base rate of poor performance validity, as measured by failure of the MSVT in conjunction with an embedded PVT (FCR, RDS, SEI), was 5.6%. Regression analyses revealed that poor performance validity predicted cognitive test performance and self-reported psychological symptom severity. Furthermore, a greater prevalence of traumatic brain injury (TBI), Post-Traumatic Stress Disorder (PTSD), co-morbid TBI/PTSD, and other Axis I diagnoses, was observed among participants with poor effort. Although poor performance validity is relatively uncommon in a research setting, these findings demonstrate that clinicians should be cautious when interpreting psychological symptoms and neuropsychological test performance of Veteran participants who fail effort measures.

TOMM Trial 1 as a performance validity indicator in a criminal forensic sample.

Abstract: Objective: To determine the effectiveness of the Test of Memory Malingering Trial 1 (TOMM1) as a freestanding Performance Validity Test (PVT) as compared to the full TOMM in a criminal forensic sample.Method: Participants included 119 evaluees in a Midwestern forensic hospital. Criterion groups were formed based on passing/failing scores on other freestanding PVTs. This resulted in three groups: +MND (Malingered Neurocognitive Dysfunction), who failed two or more freestanding PVTs; possible MND (pMND), who failed one freestanding PVT; and –MND, who failed no other freestanding PVTs. All three groups were compared initially, but only +MND and –MND groups were retained for final analyses. TOMM1 performance was compared to standard TOMM performance using Receiver Operating Characteristic (ROC) analyses.Results: TOMM1 was highly predictive of the standard TOMM decision rules (AUC = .92). Overall accuracy rate for TOMM1 predicting failure on 2 PVTs was quite robust as well (AUC = .80), and TOMM1 ≤ 39 p...