The Importance of the Morel Emotional Numbing Test Instructions: A Diagnosis Threat Induction Study.

Objective: Marketed as a validity test that detects feigning of posttraumatic stress disorder (PTSD), the Morel Emotional Numbing Test for PTSD (MENT) instructs examinees that PTSD may negatively affect performance on the measure. This study explored the potential that MENT performance depends on inclusion of "PTSD" in its instructions and the nature of the MENT as a performance validity versus a symptom validity test (PVT/SVT).

Method: 358 participants completed the MENT as a part of a clinical neuropsychological evaluation. Participants were either administered the MENT with the standard instructions (SIs) that referenced "PTSD" or revised instructions (RIs) that did not. Others were administered instructions that referenced "ADHD" rather than PTSD (AI). Comparisons were conducted on those who presented with concerns for potential traumatic-stress related symptoms (SI vs. RI-1) or attention deficit (AI vs. RI-2).

Results: Participants in either the SI or AI condition produced more MENT errors than those in their respective RI conditions. The relationship between MENT errors and other S/PVTs was significantly stronger in the SI: RI-1 comparison, such that errors correlated with self-reported trauma-related symptoms in the SI but not RI-1 condition. MENT failure also predicted PVT failure at nearly four times the rate of SVT failure.

Conclusions: Findings suggest that the MENT relies on overt reference to PTSD in its instructions, which is linked to the growing body of literature on "diagnosis threat" effects. The MENT may be considered a measure of suggestibility. Ethical considerations are discussed, as are the construct(s) measured by PVTs versus SVTs.