Detecting Coached Feigning of Schizophrenia with the Inventory of Problems – 29 (IOP-29) and Its Memory Module (IOP-M): A Simulation Study on a French Community Sample

Abstract

Evaluating the credibility of the respondent’s cognitive and psychological complaints is a core component of forensic mental health assessment. The Inventory of Problems-29 (IOP-29) and a new IOP-Memory module (IOP-M) are designed specifically for that purpose. Initial research suggests that they might provide practitioners with a quick and thus potentially efficient check of an examinee’s presentation credibility, based on the integration of both symptom and performance validity indicators. To contribute to emerging research on this topic, this study used a simulation design to examine the validity of the IOP-29 and IOP-M and their robustness in detecting coached feigning of schizophrenia. It is the first to extend this duo of measures to a French sample. Results from 115 volunteers supported the effectiveness of both IOP instruments. Because all participants were male, however, our findings may not generalize to females.