Forensic update: Malingering and incompetency

New response style measure hitting the market

Randy Otto and colleagues are as busy as beavers these days. I just blogged about Dr. Otto's new violence risk assessment text; now he and colleagues Jeffrey Musick and Christina Sherrod are releasing the Inventory of Legal Knowledge, a brief measure of response style for defendants undergoing adjudicative competence evaluations.

The 61-item, true-false test is orally administered and takes about 15 minutes. Questions are phrased in simple language and concern the legal process. It's highly portable for in-custody settings. And at $129 for the complete kit it's not a bad deal, considering PAR's normally hefty pricing. (You can order it now, but it won't actually release until mid-September.)

The theoretical basis is the same as for the Test of Memory Malingering and other measures of malingering; one suspects dissimulation when scores are either significantly lower than chance or significantly lower than attained by relevant normative groups.

A validation study has been published online in advance of the print edition of Assessment. The study, by the test authors, is titled: “Convergent validity of a screening measure designed to identify defendants feigning knowledge deficits related to competence to stand trial.” Here is the Abstract:

Because some defendants undergoing evaluation of their competence to stand trial may feign limitations in their ability to understand and participate in the legal process, assessment of their response style is critical. Preliminary research indicates that the Inventory of Legal Knowledge (ILK) has some potential to identify persons feigning competence related impairments. This study examined the convergent validity of the ILK using a sample of criminal defendants who, while undergoing competency evaluations, were administered the ILK and other response style measures. Moderate correlations between the ILK and these other tools provided some support for the ILK as a measure of response style.

More information is HERE.

Online review of updated SIRS malingering test

Richard Rogers' widely utilized Structured Inventory of Reported Symptoms (SIRS) has just been updated with a second edition, and forensic psychologist Steve Rubenzer of Houston, Texas (where "we don't only sing, but we dance just as good as we walk") has a critical review in the Open Access Journal of Forensic Psychology. The abstract:

The Structured Inventory of Reported Symptoms-2 (SIRS-2) contains significant changes designed to prevent false-positive and false-negative classification errors. While the SIRS-2 has many laudatory features, the manual contains some erroneous and questionable statistics and arguments, and authors sometimes stray from the best practices advocated by the first author. The SIRS-2 is a strong choice for assessing feigned psychosis and severe psychopathology. However, evidence for its value in assessing many other conditions, particularly somatic complaints and feigned cognitive impairment, is quite limited.

The full review is online HERE.

Overview: Feigning adjudicative incompetence

And, there's more! Sherif Soliman and Phillip J. Resnick have an overview of accepted methods for detecting feigning in competency evaluations, including specific instruments and their limitations, forthcoming from in an upcoming issue of Behavioral Sciences & the Law that is now online in advance of the print edition. The abstract:

Competence to stand trial (adjudicative competence) is the most requested forensic psychiatric evaluation, with an estimated 60,000 referrals annually. The challenge of detecting feigned incompetence has not been systematically studied until the past decade. Estimates of feigned adjudicative incompetence vary from 8 to 21%. This article reviews techniques for detecting malingered psychosis and malingered cognitive impairment during competence evaluations. Specific techniques for assessing feigned adjudicative incompetence and estimating the malingerer's genuine abilities are discussed. A stepwise approach to suspected feigned adjudicative incompetence is proffered.

Since this manuscript was already in press when the new ILK and the revised SIRS-2 were released, these instruments are not reviewed. In addition to a basic overview of instruments, however, Soliman and Resnick also describe a structured approach. As the authors point out, "Unlike many other evaluations, the assessment of adjudicative competence does not end with the determination that the defendant is malingering." Even with an uncooperative individual, the evaluator must make an effort to determine the subject's genuine capabilities.

Correspondence about that article should go to Dr. Soliman, Senior Clinical Instructor of Psychiatry at Case Western Reserve University in Ohio.