Detection of Feigning of Different Symptom Presentations With the PAI and IOP-29

Classification accuracy and resistance to coaching of the Spanish version of the Inventory of Problems-29 and the Inventory of Problems-Memory: A simulation study with mTBI patients

Objective: The present study aims to evaluate the classification accuracy and resistance to coaching of the Inventory of Problems-29 (IOP-29) and the IOP-Memory (IOP-M) with a Spanish sample of patients diagnosed with mild traumatic brain injury (mTBI) and healthy participants instructed to feign. Method: Using a simulation design, 37 outpatients with mTBI (clinical control group) and 213 non-clinical instructed feigners under several coaching conditions completed the Spanish versions of the IOP-29, IOP-M, Structured Inventory of Malingered Symptomatology, and Rivermead Post Concussion Symptoms Questionnaire. Results: The IOP-29 discriminated well between clinical patients and instructed feigners, with an excellent classification accuracy for the recommended cutoff score (FDS ≥ .50; sensitivity = 87.10% for coached group and 89.09% for uncoached; specificity = 95.12%). The IOP-M also showed an excellent classification accuracy (cutoff ≤ 29; sensitivity = 87.27% for coached group and 93.55% for uncoached; specificity = 97.56%). Both instruments proved to be resistant to symptom information coaching and performance warnings. Conclusions: The results confirm that both of the IOP measures offer a similarly valid but different perspective compared to SIMS when assessing the credibility of symptoms of mTBI. The encouraging findings indicate that both tests are a valuable addition to the symptom validity practices of forensic professionals. Additional research in multiple contexts and with diverse conditions is warranted.

Using the MMPI-2-RF, IOP-29, IOP-M, and FIT in the In-Person and Remote Administration Formats: A Simulation Study on Feigned mTBI

Our study compared the impact of administering Symptom Validity Tests (SVTs) and Performance Validity Tests (PVTs) in in-person versus remote formats and assessed different approaches to combining validity test results. Using the MMPI-2-RF, IOP-29, IOP-M, and FIT, we assessed 164 adults, with half instructed to feign mild traumatic brain injury (mTBI) and half to respond honestly. Within each subgroup, half completed the tests in person, and the other half completed them online via videoconferencing. Results from 2 ×2 analyses of variance showed no significant effects of administration format on SVT and PVT scores. When comparing feigners to controls, the MMPI-2-RF RBS exhibited the largest effect size (d = 3.05) among all examined measures. Accordingly, we conducted a series of two-step hierarchical logistic regression models by entering the MMPI-2-RF RBS first, followed by each other SVT and PVT individually. We found that the IOP-29 and IOP-M were the only measures that yielded incremental validity beyond the effects of the MMPI-2-RF RBS in predicting group membership. Taken together, these findings suggest that administering these SVTs and PVTs in-person or remotely yields similar results, and the combination of MMPI and IOP indexes might be particularly effective in identifying feigned mTBI.

On the Use of Eye Movements in Symptom Validity Assessment of Feigned Schizophrenia

Assessing the credibility of reported mental health problems is critical in a variety of assessment situations, particularly in forensic contexts. Previous research has examined how the assessment of performance validity can be improved through the use of bio-behavioral measures (e.g., eye movements). To date, however, there is a paucity of literature on the use of eye tracking technology in assessing the validity of presented symptoms of schizophrenia, a disorder that is known to be associated with oculomotor abnormalities. Thus, we collected eye tracking data from 83 healthy individuals during the completion of the Inventory of Problems – 29 and investigated whether the oculomotor behavior of participants instructed to feign schizophrenia would differ from those of control participants asked to respond honestly. Results showed that feigners had a longer dwell time and a greater number of fixations in the feigning-keyed response options, regardless of whether they eventually endorsed those options (d > 0.80). Implications on how eye tracking technology can deepen comprehension on simulation strategies are discussed, as well as the potential of investigating eye movements to advance the field of symptom validity assessment.

The sensitivity of the IOP-29 and IOP-M to coached feigning of depression and mTBI: An online simulation study in a community sample from the United Kingdom

Assessing the credibility of symptoms is critical to neuropsychological assessment in both clinical and forensic settings. To this end, the Inventory of Problems-29 (IOP-29) and its recently added memory module (Inventory of Problems-Memory; IOP-M) appear to be particularly useful, as they provide a rapid and cost-effective measure of both symptom and performance validity. While numerous studies have already supported the effectiveness of the IOP-29, research on its newly developed module, the IOP-M, is much sparser. To address this gap, we conducted a simulation study with a community sample (N = 307) from the United Kingdom. Participants were asked to either (a) respond honestly or (b) pretend to suffer from mTBI or (c) pretend to suffer from depression. Within each feigning group, half of the participants received a description of the symptoms of the disorder to be feigned, and the other half received both a description of the symptoms of the disorder to be feigned and a warning not to over-exaggerate their responses or their presentation would not be credible. Overall, the results confirmed the effectiveness of the two IOP components, both individually and in combination.

A Survey of Practices and Beliefs of Italian Psychologists Regarding Malingering and Symptom Validity Assessment

A few years ago, an article describing the current status of Symptom Validity Assessment (SVA) practices and beliefs in European countries reported that there was little research activity in Italy (Merten et al., 2013). The same article also highlighted that Italian practitioners were less inclined to use Symptom Validity Tests (SVTs) and Performance Validity Tests (PVTs) in their assessments, compared with their colleagues from other major European countries. Considering that several articles on malingering and SVA have been published by Italian authors in recent years, we concluded that an update of the practices and beliefs of Italian professionals regarding malingering and SVA would be beneficial. Accordingly, from a larger survey that examined general psychological assessment practices and beliefs of Italian professionals, we extracted a subset of items specifically related to malingering and SVA and analyzed the responses of a sample of Italian psychologists who have some experience with malingering-related assessments. Taken together, the results of our analyses indicated that even though our respondents tend to use SVTs and PVTs relatively often in their evaluations, at this time, they likely trust more their own personal observations, impressions, and overall clinical judgment, in their SVA practice. Additionally, our results also indicated that Italian practitioners with some familiarity with malingering-related evaluations consider malingering to occur in about one-third of psychological assessments in which the evaluee might have an interest in overreporting.