Detection of Feigned Crime-Related Amnesia: A Multi-Method Approach

Abstract

Claims of crime-related amnesia appear to be common. Using a mock crime approach, the diagnostic power of seven symptom validity instruments was investigated. Sixty participants were assigned to three conditions: responding honestly; feigning crime-related amnesia; feigning amnesia with a warning not to exaggerate. High sensitivity and specificity were obtained for the Structured Inventory of Malingered Symptomatology, the Amsterdam Short-Term Memory Test, and the Morel Emotional Numbing Test. Only three warned malingerers went undetected. The results demonstrate that validated instruments exist to support forensic decision making about crime-related amnesia. Yet, warning may undermine their effectiveness, even when using a multi-method approach.

The Structured Inventory of Malingered Symptomatology (SIMS): A Systematic Review and Meta-Analysis

“…For example, the SIMS attained a higher sensitivity than the ASTM among respondents who were coached and asked to feign cognitive impairment (detection rates of .90 and .70, respectively; Jelicic, Merckelbach, Candel, & Geraerts, 2007). The sensitivity of the SIMS matched that of the ASTM in a study on the effects of forewarning among experimental feigners of cognitive dysfunction (Giger, Merten, Merckelbach, & Oswald, 2010). In addition, Jelicic, Ceunen, Peters, and Merckelbach (2011) found the SIMS to be as sensitive as the TOMM when coached feigners simulated cognitive problems (detection rates of .87 and .86, respectively).…”

“…Using the SIMS in conjunction with other validity tests allows for a significant reduction in false-positive risk; namely, through adherence to the rule that a respondent has to fail at least two validity tests in order to be classified as a feigner (Giger et al, 2010). Clinicians and researchers who decide to employ the SIMS are welladvised to bear this rule, also known as the two-failure rule (Victor et al, 2009), in mind.…”

“…This might reflect a common strategy among feigners-the tendency to overgeneralize when reporting symptoms. Studies involving experimental feigners typically find that, in spite of instructions to feign specific symptoms, participants are inclined to overgeneralize and report a diversity of symptoms (e.g., Giger et al, 2010;. Clegg et al (2009) noted that experimental feigners who were instructed to feign depression and patients who were suspected of feigning a mood disorder were just as likely to fail the SIMS as they were to fail the Affective Disorders subscale.…”

“…While the sensitivity of a SIMS subscale might thus benefit from certain contexts, it rarely exceeds that of the SIMS total score. Subscales that attain high sensitivity when confronted with their target psychopathology are Affective Disorders, Neurological Impairment, and Amnestic Disorders (Benge et al, 2012;Clegg, Fremouw, & Mogge, 2009;Giger et al, 2010). The Low Intelligence subscale remains relatively insensitive to explicit attempts to mimic poor intellectual abilities (Clegg et al, 2009).…”

Symptom validity assessment in European countries: Development and state of the art

“…Only few published studies are authored from psychologists of other nationalities, such as Austria (e.g., Schiemann, 2003), Portugal (Martins & Martins, 2010;Simões et al, 2010), or Switzerland (Giger, Merten, Merckelbach, & Oswald, 2010) while there is no or almost no evidence for substantial research activities in some major European nations like France or Italy. This might reflect large differences in the degree of acceptance that symptom validity assessment has reached within Europe.…”