Date of Award


Publication Type

Doctoral Thesis

Degree Name





Clinical psychology, Cognitive psychology


Laszlo A Erdodi




The current study explored the effects of cultural, demographic and psychiatric variables on Performance Validity Test (PVT) base rates of failure (BRFAIL) in 325 examinees with traumatic brain injury (TBI) following motor vehicle accidents. PVTs are widely used measures of credibility in neuropsychological assessment. Gaps in the PVT literature regarding the effects of various demographic, cultural, and psychiatric factors limit the generalizability of PVTs. Higher false-positive rates in minority groups may lead to the inaccurate characterization of members as noncredible, resulting in the denial of treatment and compensation following injuries. To address this gap in the literature, the first objective of the study explored the relationship between BRFAIL, and limited English proficiency, time spent in Canada, education, age, gender, and injury severity. Results indicated that examinees with limited English proficiency had higher BRFAIL on PVTs with low verbal mediation (i.e., tests that did not have verbal components beyond the instructions) compared to Anglophone Canadians. Examinees who had language interpreters had higher BRFAIL on PVTs with both high and low verbal mediation compared to examinees assessed in English. Examinees who immigrated to Canada had higher BRFAIL on both high and low verbal mediation PVTs compared to Canadian-born examinees. Examinees aged 40 to 49 and those with less than high school education had higher BRFAIL for low verbal mediation PVTs than other groups. There were no differences for gender or TBI severity on BRFAIL. These results may be explained by several cultural factors, including cultural concepts of distress and differences in health literacy, which may contribute to PVT BRFAIL. As such, neuropsychologists should consider the contribution of these cultural factors when interpreting PVT results of examinees who have immigrated to Canada. Another important gap in the literature is in regards the relationship between PVTs and dissociative symptoms (i.e., disrupted consciousness, affect, and memory). Findings on the effects of psychiatric factors (e.g., posttraumatic, depressive, and anxious symptoms) on PVT BRFAIL are mixed but generally indicate that PVTs are robust to psychiatric disorders except psychosis. However, disruptions in consciousness, memory, and affect due to dissociative pathology might be expected to interfere with test performance. The second objective of this study explored the relationship between BRFAIL and dissociative, posttraumatic, anxious, and depressive symptoms. Results indicated elevated rates of PVT BRFAIL for examinees with higher levels of self-reported posttraumatic, depressive, and anxious symptoms. Results also indicated that those with high self-reported dissociative symptoms had higher BRFAIL for verbally mediated PVTs. The findings suggest that dissociative symptoms may interfere with verbally mediated PVTs, and highlight the need for further research into the effects of dissociative pathology on neuropsychological and PVT performance. The current study demonstrated that previously unexplored cultural, demographic, and psychiatric factors are related to PVT performance, and may affect the interpretation of PVTs. Implications, limitations, and avenues for future research are discussed.