Types of Malingering in PTSD: Evidence from a Psychological Injury Paradigm

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.

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.

Strategies of feigning mild head injuries related to validity indicators and types of coaching: Results of two experimental studies

OBJECTIVE

In this paper, we analyzed differences between uncoached, symptom-coached, and test-coached simulators regarding strategies of feigning mild head injuries.

METHOD

Healthy undergraduates (n = 67 in the first study; n = 48 in the second study), randomized into three simulator groups, were assessed with four experimental memory tests. In the first study, tests were administered face-to-face, while in the second study, the procedure was adapted for online testing.

RESULTS

Online simulators showed a different approach to testing than face-to-face participants (U tests  < 920, p < .05). Nevertheless, both samples favored strategies like memory loss, error making, concentration difficulties, and slow responding. Except for slow responding and concentration difficulties, the favorite strategies correlated with validity indicators. In the first study, test-coached simulators (m = 4.58-5.68, SD = 2.2-3) used strategies less than uncoached participants (m = 5.25-5.88, SD = 2.26-2.84). In the second study, test-coached participants (m = 3.8-5.6, SD = 1.51-2.2) employed strategies less than uncoached (m = 6.21-7.29, SD = 1.25-1.85) and symptom-coached participants (m = 6.14-6.79, SD = 1.69-2.76).

DISCUSSION

Similarities and differences between online and face-to-face assessments are discussed. Recommendations to associate heterogeneous indicators for detecting feigning strategies are issued.

Take Their Word for It: The Inventory of Problems Provides Valuable Information on Both Symptom and Performance Validity

This study was designed to compare the validity of the Inventory of Problems (IOP-29) and its newly developed memory module (IOP-M) in 150 patients clinically referred for neuropsychological assessment. Criterion groups were psychometrically derived based on established performance and symptom validity tests (PVTs and SVTs). The criterion-related validity of the IOP-29 was compared to that of the Negative Impression Management scale of the Personality Assessment Inventory (NIM_PAI) and the criterion-related validity of the IOP-M was compared to that of Trial-1 on the Test of Memory Malingering (TOMM-1). The IOP-29 correlated significantly more strongly (z = 2.50, p = .01) with criterion PVTs than the NIM_PAI (r_IOP-29 = .34; r_NIM-PAI = .06), generating similar overall correct classification values (OCC_IOP-29: 79-81%; OCC_NIM-PAI: 71-79%). Similarly, the IOP-M correlated significantly more strongly (z = 2.26, p = .02) with criterion PVTs than the TOMM-1 (r_IOP-M = .79; r_TOMM-1 = .59), generating similar overall correct classification values (OCC_IOP-M: 89-91%; OCC_TOMM-1: 84-86%). Findings converge with the cumulative evidence that the IOP-29 and IOP-M are valuable additions to comprehensive neuropsychological batteries. Results also confirm that symptom and performance validity are distinct clinical constructs, and domain specificity should be considered while calibrating instruments.

An Eye Tracking Study on Feigned Schizophrenia

Research on malingering detection has not yet taken full advantage of eye tracking technology. In particular, while several studies indicate that patients with schizophrenia behave notably differently from controls on specific oculomotor tasks, no study has yet investigated whether experimental participants instructed to feign could reproduce those behaviors, if coached to do so. Due to the automatic nature of eye movements, we anticipated that eye tracking analyses would help detect feigned schizophrenic problems. To test this hypothesis, we recorded the eye movements of 83 adult UK volunteers, and tested whether eye movements of healthy volunteers instructed to feign schizophrenia (n = 43) would differ from those of honest controls (n = 40), while engaging in smooth pursuit and pro- and anti-saccade tasks. Additionally, results from our investigation were also compared against previously published data observed in patients with schizophrenia performing similar oculomotor tasks. Data analysis showed that eye movements of experimental participants instructed to feign (a) only partially differed from those of controls and (b) did not closely resemble those from patients with schizophrenia reported in previously published papers. Taken together, these results suggest that examination of eye movements does have the potential to help detecting feigned schizophrenia.

Health and return to work in the first two years following road traffic injury: a comparison of outcomes between compensation claimants in Victoria and New South Wales, Australia

BACKGROUND

People who sustain road traffic injuries often have poor health outcomes. While outcomes are often worse in people with a compensation claim, especially in fault-based schemes versus no-fault schemes, few studies have directly compared outcomes across scheme types.

OBJECTIVE

To compare health and work outcomes between people who had no compensation claim, a fault-based claim, or "no-fault" transport or workers compensation claim after hospitalisation for a road traffic injury.

METHODS

Participants aged >=18 years admitted to hospital in New South Wales or Victoria for >24 hours were recruited in two separate prospective cohort studies (N=1,034). People who died or sustained minor or very severe injuries were excluded. Groups included Compulsory Third Party (fault-based, n=128), no-fault Transport Accident Commission (TAC; n=454) and workers compensation claimants (n=73), or no claim (n=226). Outcomes at six, 12- and 24-months post-injury included health [SF-12 Mental Component Score (MCS) and Physical Component Score (PCS)], and return to work for people working pre-injury. Multivariable mixed effects linear and logistic regressions, adjusting for demographic and injury covariates, examined differences in health and work outcomes between claimant groups, with fixed effects of time and random effects of participant ID.

RESULTS

Health status was better in people with a no-fault TAC claim (MCS: m=50.62, 95%CI:49.62,51.62; PCS: m=40.49, 95%CI:39.46,41.52) or no claim (MCS: m=49.99, 95%CI:49.62,51.62; PCS: m=44.36, 95%CI:43.00,45.72), than people with a workers compensation (MCS: m=45.73, 95%CI:43.46,48.00; PCS: m=38.94, 95%CI:36.59,41.30) or fault-based CTP claim (MCS: m=41.34, 95%CI:39.54,43.13; PCS: m=35.64, 95%CI:33.78,37.49). Relative to fault-based CTP claimants, the odds of returning to work were higher for people with no claim (AOR=6.84, 95%CI:1.73,27.05) but did not differ for no-fault TAC (AOR=1.21, 95%CI:0.36,4.05) or workers compensation claimants (AOR=0.83,95%CI: 0.17,3.99). While people with a fault-based CTP claim had poorer mental and physical health and return to work after injury, they showed greater improvements in mental health, and similar levels of improvement in physical health and work participation over time to the other groups.

CONCLUSION

The patterns of health and work across scheme types provide important insights against which we can contrast the effects of future scheme designs on client outcomes.