A proof-of-concept randomized crossover clinical trial of a first-in-class vasopressin 1a receptor antagonist for PTSD: Design, methods, and recruitment

Background

Almost eight million Americans suffer from Posttraumatic Stress Disorder (PTSD). Current PTSD drug therapies rely on repurposed antidepressants and anxiolytics, which produce undesirable side effects and have recognized compliance issues. Vasopressin represents a promising and novel target for pharmacological intervention. Logistical issues implementing a clinical trial for a novel PTSD pharmaceutical are relatively uncharted territory as trials concerning a new agent have not been published in the past several decades. All published trials have repurposed FDA-approved psychoactive medications with known risk profiles. Our recruitment challenges are discussed in this context.

Methods

An 18-week proof-of-concept randomized crossover clinical trial of a first-in-class vasopressin 1a receptor antagonist (SRX246) for PTSD was conducted. All participants received SRX246 for 8 weeks, the placebo for 8 weeks, and the drug vs. placebo arms were compared. Participants were assessed every 2 weeks for PTSD symptoms as well as other medication effects. Results were expected to provide an initial demonstration of safety and tolerability in this clinical population and potentially clinical efficacy in SRX246-treated patients measured by Clinician Administered PTSD Scale (CAPS) score changes, clinical impression, and other indices compared to placebo. The primary hypothesis was that SRX246 would result in a clinically meaningful 10-point reduction in mean CAPS score compared to placebo.

Discussion

This study is the first to investigate an oral vasopressin 1a receptor antagonist for PTSD. As a wave of PTSD clinical trials with new pharmaceutical compounds are beginning now, lessons learned from our recruitment challenges may be invaluable to these endeavors.

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.

Structured Interview of Reported Symptoms-2nd Edition (SIRS-2): Use and Admissibility in Forensic Mental Health Assessment

Assessment of symptom feigning is paramount in forensic psychological and psychiatric assessment. The Structured Interview of Reported Symptoms, 2nd Edition (SIRS-2; Rogers et al., 2010) is a revised edition to the original SIRS (Rogers et al., Structured Interview of Reported Symptoms (SIRS) and professional manual. Psychological Assessment Resources, Inc, 1992) and was developed to assess feigned psychiatric symptoms. The current paper reviews use of the SIRS-2 in forensic assessment, specifically addressing topics such as translations of the instrument, its use in assessing psychiatric and cognitive feigning, and its use in special populations. Empirical foundation and psychometric properties of the SIRS-2 is also covered. The SIRS-2 was revised in part to reduce false positive classifications of feigning. Research suggests that this goal was largely accomplished, albeit at the expense of reduced sensitivity. The paper also provides a review of federal and state appellate cases that mention the SIRS-2. Notably, most cases that cite the SIRS-2 do not actually center on the SIRS-2, and the test's admissibility has never been outrightly challenged. The paper concludes with a discussion of expert testimony concerning the SIRS-2.

The association between clinicians' initial judgments of feigning and outcomes on symptom validity measures among pretrial forensic psychiatric inpatients

Research suggests the use of validated symptom validity tests to detect feigning is imperative to increase accuracy over unaided clinical judgment, especially in forensic settings. This study examined performance on the Miller Forensic Assessment of Symptoms (M-FAST) and Structured Interview of Reported Symptoms (SIRS) during 297 assessments of forensic inpatients. The risk of being identified as feigning on the M-FAST or SIRS was similar for those who were referred for evaluation of feigning compared to those who were not, but individuals with malingering designations prior to the evaluation scored significantly higher than those without on the M-FAST and several SIRS subscales. Findings support the importance of utilizing objective methods of data collection.

The Development of the Inventory of Problems-29: A Brief Self-Administered Measure for Discriminating Bona Fide From Feigned Psychiatric and Cognitive Complaints

This article describes the development of the Inventory of Problems-29 (IOP-29), a new, short, paper-and-pencil, self-administered measure of feigned mental and cognitive disorders. Four clinical comparison simulation studies were conducted. Study 1 (n = 451) selected the items and produced an index of potential feigning. Study 2 (n = 331) scaled this index to produce a probability score, and examined its psychometric properties. Study 3 tested the generalizability of Study 2's findings with 2 additional samples (ns = 128 and 90). Results supported the utility of the IOP-29 for discriminating bona fide from feigned psychiatric and cognitive complaints. Validity was demonstrated in feigning mild traumatic brain injury, psychosis, posttraumatic stress disorder, and depression. Within the independent samples of Studies 2 and 3, the brief IOP-29 performed similarly to the MMPI-2 and Personality Assessment Inventory, and perhaps better than the Test of Memory Malingering. Classifications within these samples with base rates of .5 produced sensitivity, specificity, positive predictive power, and negative predictive power statistics of about .80. Further research is needed testing the IOP-29 in ecologically valid field studies.

The Relationship Between Psychiatric and Cognitive Symptom Feigning Among Forensic Inpatients Adjudicated Incompetent to Stand Trial

The accurate assessment of feigning is an important component of forensic assessment. Two potential strategies of feigning include the fabrication/exaggeration of psychiatric impairments and the fabrication/exaggeration of cognitive deficits. The current study examined the relationship between psychiatric and cognitive feigning strategies using the Structured Interview of Reported Symptoms and Test of Memory Malingering among 150 forensic psychiatric inpatients adjudicated incompetent to stand trial. A greater number of participants scored within the feigning range on the Structured Interview of Reported Symptoms than on the Test of Memory Malingering. Relative risk ratios indicated that individuals shown to be feigning cognitive deficits were 1.68 times more likely to feign psychiatric symptoms than those not shown to be feigning cognitive deficits. Likewise, individuals shown to be feigning psychiatric deficits were 1.86 times more likely to feign cognitive deficits than those not shown to be feigning psychiatric symptoms. Overall, findings suggest that psychiatric feigning and cognitive feigning are related, but can be employed separately as feigning strategies. Therefore, clinicians should consider evaluating for both feigning strategies in forensic assessments where cognitive and psychiatric symptoms are being assessed.

A Meta-Analysis of Malingering on the MMPI-2

With the widespread adoption of the MMPI-2 as an assessment tool, psychologists are frequently required to make important decisions regarding the validity of its clinical profiles and a determination of malingering. Ten MMPI-2 fake-bad scales/indexes are reviewed with respect to their potential usefulness in the evaluation of feigning mental illness. In addition, a meta-analysis of the MMPI-2 was performed. Of the six indicators with sufficient research, we found that the instrument's F, F-K, and O-S had very strong effect sizes, which were maintained across both nonclinical controls and psychiatric groups. Specific recommendations are made for clinical practice and applied research.

The Recognition Memory Test, Digit Span, and Knox Cube Test as Markers of Malingered Memory Impairment

The purpose of this investigation was to examine the efficacy of using the Recognition Memory Test (RMT), Digit Span subtest (WAIS-R), and Knox Cube Test as markers for malingered memory deficits. Participants were 100 subjects from three general populations: university students, federal inmates, and patients with head injuries. Twenty students, 20 inmates, and 20 patients with head injuries resulting in memory impairment were instructed to try their best on the assessment procedures. The remaining 20 students and 20 inmates were instructed to malinger memory impairment on the procedures. The experimental-malingerers (i.e., students and inmates) performed more poorly than the patients with head injuries on nearly every score derived from the three tests. Discriminant function analyses using the age-corrected Digit Span scale score, the Knox Cube Test total score, and the RMT raw scores for words and faces as predictors of group membership resulted in an overall 98% correct classification rate and 100% correct on cross-validation. Simultaneously applying two empirically-derived RMT cutoff scores resulted in an overall correct classification rate of 100%. The extraordinarily high classification rates in this study were likely influenced by the experimental design and procedures.

Antisocial features and "faking bad": A critical note

We critically review the literature on antisocial personality features and symptom fabrication (i.e., faking bad; e.g., malingering). A widespread assumption is that these constructs are intimately related. Some studies have, indeed, found that antisocial individuals score higher on instruments detecting faking bad, but others have been unable to replicate this pattern. In addition, studies exploring whether antisocial individuals are especially talented in faking bad have generally come up with null results. The notion of an intrinsic link between antisocial features and faking bad is difficult to test and research in this domain is sensitive to selection bias. We argue that research on faking bad would profit from further theoretical articulation. One topic that deserves scrutiny is how antisocial features affect the cognitive dissonance typically induced by faking bad. We illustrate our points with preliminary data and discuss their implications.

The detection of feigning using multiple PAI scale elevations: a new index

Archival data were collected from 98 male inmates at a psychiatric inpatient unit to examine the utility of the Multiscale Feigning Index (MFI) as a proposed feigning index for the Personality Assessment Inventory (PAI). MFI was compared with existing PAI feigning indices, Malingering (MAL), Negative Impression Management (NIM), and Rogers Discriminant Function (RDF), using performance on the Structured Interview of Reported Symptoms (SIRS) as the feigning criterion. Regression analyses revealed that MFI was a stronger predictor of SIRS outcome than NIM, MAL, and RDF. In addition, NIM, MAL, and RDF did not add substantial incremental validity to MFI in predicting SIRS outcome. Receiver operating characteristic analyses revealed sensitivity of 68.89% and specificity of 94.34% at an MFI cutoff of more than 76, which compared favorably with the utility of NIM, MAL, and RDF.

The Utility of the Structured Interview of Reported Symptoms in a Sample of Individuals With Intellectual Disabilities

The challenges of accurate forensic assessment are aggravated when evaluatees have intellectual disabilities. Few studies have addressed the efficacy of forensic assessment in samples diagnosed with an intellectual disability, and those that have typically focus on measures of cognitive effort rather than on feigned psychiatric symptoms. This study focuses on the applicability of the original and revised versions of the Structured Interview of Reported Symptoms (SIRS) in a sample of participants with genuine intellectual disabilities. The SIRS was administered to 43 individuals diagnosed with intellectual disabilities, all of whom were asked to respond honestly. A considerable proportion of these respondents were misclassified as feigning psychiatric symptoms. These misclassifications were most frequent when the respondents had comorbid psychiatric diagnoses. The updated scoring algorithm of the SIRS-2 generated a rate of misclassifications that was substantially lower but that still exceeded published normative data. The implications for forensic assessment are discussed.

The utility of the MMPI-2 malingering discriminant function index in the detection of malingering: a study of criminal defendants

This study examined the utility of the Minnesota Multiphasic Personality Inventory-2's (MMPI-2) malingering discriminant function index (M-DFI), recently developed by Bacchiochi and Bagby, in the detection of malingering in a forensic sample. Criminal defendants were divided into "malingering" and "not malingering" groups using the structured interview of reported symptoms (SIRS) criteria proposed by Rogers. Logistic regression analysis (LRA) revealed that the MMPI-2 infrequency (F) scale had the best predictive utility of the traditional infrequency scales. Although the M-DFI did significantly differentiate the malingering from the not malingering groups, it did not add significantly to the predictive utility of the MMPI-2 F scale. Receiver operating characteristics analyses demonstrated acceptable sensitivity and specificity for the MMPI-2 F scale, but poor sensitivity for the M-DFI scale. The results are discussed in terms of the utility of the M-DFI in detecting malingering and problems of extending the findings of simulation studies to the forensic context.

Validation of an abbreviated version of the structured interview of reported symptoms in outpatient psychiatric and community settings

This study examined the effectiveness of an abbreviated version of the Structured Interview of Reported Symptoms (SIRS-A) in identifying malingered mental illness. The SIRS-A is comprised of 69 items drawn from the SIRS (R. Rogers et al. 1992, SIRS: Structured Interview of Reported Symptoms: Professional Manual. Odessa, FL: Psychological Assessment Resources, Inc.), substantially reducing the administration time. A simulation design was used with three samples; 87 psychiatric outpatients who responded honestly were compared to 29 community-dwelling adults and 24 psychiatric patients instructed to malinger psychopathology. The SIRS-A generated sensitivity comparable to or exceeding that of the SIRS normative data, but specificity was poorer; many genuinely impaired patients were misclassified as malingering. Although these findings suggest the SIRS-A may be an effective means to assess malingering in psychiatric populations, further research assessing the reasons for the elevated false positive rates is necessary.

Detection of Malingering of Psychiatric Disorder With the Personality Assessment Inventory: An Investigation of Criminal Defendants

To assess the diagnostic accuracy of the Personality Assessment Inventory (PAI; Morey, 1991) Validity scales for the detection of malingered psychiatric disorders, we divided a sample of criminal defendants referred for forensic evaluation by the federal courts into malingering and not malingering groups based on their performance on the Structured Interview of Reported Symptoms (Rogers, Gillis, & Bagby, 1990). Logistic regression analyses (LGAs) revealed that there were no differences between the malingering and not malingering groups with respect to age, race, years of education, history of drug abuse, or number of previous felony convictions. LGA with malingering versus not malingering as the criterion revealed that the PAI Negative Impression Management (NIM) scale but not the Rogers Discriminant Function (RDF; Rogers, Sewell, Morey & Ustad, 1996) nor the Malingering index (MAL; Morey, 1996) significantly differentiated the malingering from the not malingering group. Receiver operating characteristics analyses demonstrated acceptable sensitivity and specificity for the NIM scale but not the RDF scale or the MAL index. We discuss the results in terms of the suggested cutoff scores for the PAI Validity scales in detecting criminal defendants who are attempting to feign psychiatric disorder.

Detection and management of malingering in people presenting for treatment of posttraumatic stress disorder: methods, obstacles, and recommendations

Malingering of symptoms of posttraumatic stress disorder (PTSD) has become a growing concern, particularly in healthcare and other settings in which the diagnosis is associated with financial incentives such as disability benefits. Although there is a steadily increasing body of research on methods for detecting PTSD malingering, little has been written on the assessment and practical management of malingering in treatment settings. The present article addresses this important issue, including a review of the methods, obstacles, and possible solutions for assessing PTSD malingering, along with suggestions for managing cases in which malingering is strongly suspected.

Psychopathy and malingering of psychiatric disorder in criminal defendants

Because the use of deception is an important clinical characteristic of psychopathy, there is intuitive appeal to the idea that psychopathy and malingering are associated. There is, however, very little research showing that psychopaths are more likely to malinger. We classified a sample of criminal defendants as high, moderate, or low in psychopathy, based on PCL-R scores, and compared their scores on indices typically used to detect malingering on the MMPI-2, the PAI and the SIRS. The high psychopathy group scored significantly higher on the MMPI-2 F and F-K; the PAI NIM, and the SIRS, but not the MMPI-2 Fb, F(p), or the PAI RDF or Mal, lending some support for the DSM-IV recommendation that malingering should be considered whenever there is a diagnosis of antisocial personality disorder. Logistic regression analysis (LGA) revealed that Factor I but not Factor II of the PCL-R significantly discriminated malingerers from nonmalingerers with 75% correct classification. However, receiver operating characteristic (ROC) analysis revealed that psychopathy ratings had poor sensitivity and specificity in the detection of malingering. Calculation of the percentages of those exceeding accepted cut-offs on each of the malingering measures revealed that a high percentage of severe psychopaths did not attempt to feign psychiatric disorder. The results suggest that psychopathy is not a clinically useful indictor of malingering. The results are discussed in terms of confirmatory bias and the impact such a bias could have on the evaluation of criminal defendants.

Response style and posttraumatic stress disorder (PTSD): a review

Response style is an important issue that is often not addressed when assessing or treating patients with posttraumatic stress disorder (PTSD). In this paper, various response styles are discussed along with their relevance to clinical work and research with PTSD patients. Two of the most prevalent measures of response style, the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and Structured Interview of Reported Symptoms (SIRS) scales are evaluated for use in assessing for PTSD. In addition, the Trauma Symptom Inventory's potential for use in evaluating response style is briefly discussed. Implications for future work and directions for future investigation are outlined.

Comparability of the MMPI-2 F(p) and F scales and the SIRS in clinical use with suspected malingerers

Relationships among Structured Interview of Reported Symptoms (SIRS) scores and Minnesota Multiphasic Personality Inventory--2 (MMPI-2) F(p) and F scores were examined for 63 suspected malingerers evaluated at either of two psychiatric facilities. Despite differences between facilities in terms of seriousness of subjects' offenses, mean scores on the malingering tests were similar. Cutting scores for F(p) and F resulting in substantial correspondence between these scales and the SIRS were derived. Use of the cut score for F(p) proposed by Arbisi and Ben-Porath (1995) resulted in less agreement with the SIRS than did a lower cut score. No substantial difference between F(p) and F in each scale's overall agreement with the SIRS was observed. A principal components analysis of the SIRS primary scales produced two factors, interpreted as Overreporting of Symptoms and Implausible Symptoms. F(p) was observed to correlate significantly with Implausible Symptoms but not with Overreporting of Symptoms; F was significantly correlated with both factors.

Refinement of the MMPI-2 F(p) scale is not necessary: a response to Gass and Luis

Gass and Luis (2001) reported that four MMPI-2 Lie scale items contained on the F(p) scale do not measure symptom exaggeration but measure defensiveness. They hold that elimination of the four Lie scale items improves the utility of the F(p) scale in the identification of exaggeration in VA samples. To directly address the assertion that removal of the L scale items from the F(p) scale enhances the predictive validity of F(p), data derived from a previously published study where 74 psychiatric inpatients were asked to retake the MMPI-2 and either feign psychopathology or respond in an honest manner were reanalyzed. The intact F(p) scale demonstrated a stronger correlation with group membership, increased incremental validity, and superior classification rates compared with the F(p) scale without the 4 Lie scale items. Consequently, the F(p) refinement recommended by Gass and Luis is unnecessary.

Screening for feigned psychiatric symptoms in a forensic sample by using the MMPI-2 and the structured inventory of malingered symptomatology

Fifty-five men undergoing pretrial psychological evaluations for competency to stand trial or criminal responsibility in the federal justice system were administered the Structured Interview of Reported Symptoms (SIRS), the Minnesota Multiphasic Personality Inventory--2 (MMPI-2), and the Structured Inventory of Malingered Symptomatology (SIMS). On the basis of results from the SIRS, 31 were classified as honest responders and 24 as feigning. Significant differences between the 2 groups were found on all SIMS scales as well as on all tested MMPI-2 fake bad validity scales. The SIMS total score and the MMPI-2 Backpage Infrequency (Fb) scale had relatively high negative predictive power (100% and 92%, respectively). On the basis of this clinically relevant methodology, both tests have potential usefulness as screens for malingering.

An investigation of the relationship between psychopathic traits and malingering on the psychopathic personality inventory

This study employed a repeated-measures simulation design to examine (a) the specific effects of malingering on a recently developed measure of psychopathy, the Psychopathic Personality Inventory (PPI), and (b) the broader association between psychopathic traits and dissimulation. One hundred and forty-three participants completed the PPI twice (both under standard instructions and with instructions to feign psychosis), and also completed post-test questionnaires assessing their attitudes toward engaging in malingering across several hypothetical settings. When attempting to feign psychosis, participants produced elevated scores on a validity scale designed to identify deviant responding, and use of a cross-validated cutoff score with this scale produced high sensitivity and specificity rates across the honest and malingering conditions. Furthermore, PPI scores (in the honest condition) were significantly correlated with a willingness to engage in dissimulation across various hypothetical forensic/correctional scenarios. Results are discussed in terms of the "fakability" of the PPI, as well as the relationship between psychopathic personality features and malingering more generally.

Differential vulnerability between postconcussion self-report and objective malingering tests in identifying simulated mild head injury

The present study examined the ability of analog malingerers to feign postconcussion symptoms and neuropsychological performance patterns seen in mild head-injured patients. Experimental subjects were randomly assigned to either a control condition, asked to feign deficits consistent with mild head injury without task specific instruction, or feign deficits while given task-specific instruction. A separate group of mild head-injured patients served as a clinical comparison group. Analog malingering groups accurately simulated levels of postconcussive symptoms seen in the mild head-injured patients. However, poorer performance was displayed by the analog malingerers on the objective malingering tests. Coaching did not facilitate realistic patterns of performance for analog malingerers. The results of this study indicate that analog malingerers accurately replicated self-reported postconcussive symptoms, but were less able to simulate objective clinical malingering test performance. These results suggest that self-report measures of postconcussive symptoms and clinical tests are differentially vulnerable to simulation attempts.

Feigning schizophrenic disorders on the MMPI-2: detection of coached simulators

The Minnesota Multiphasic Personality Inventory (MMPI) and, more recently, its revised version (the MMPI-2) have represented the "gold standard" in the psychometric assessment of malingering and other response styles. In this study, we provide a stringent test of the MMPI-2 validity indices and their ability to detect feigned schizophrenia in four groups of simulators (n = 72). Simulators were randomly assigned to one of four conditions: (a) coached on symptoms of schizophrenia, (b) coached on strategies for the detection of fakers, (c) coached on both symptoms and strategies, or (d) uncoached. Simulators were compared to subjects responding under an honest condition (n = 13) and a comparison group of schizophrenic inpatients (n = 37). We found knowledge of strategies alone allowed many simulators (i.e., one third or more, depending on the validity indices) to elude detection. In contrast, knowledge of the disorder appeared less useful to simulators in avoiding detection. Coaching on both strategies and symptoms was not as effective as strategies alone. Consistent with previous studies, uncoached simulators were detected with moderately high levels of accuracy.

Faking specific disorders: a study of the Structured Interview of Reported Symptoms (SIRS)

An untested assumption of malingering research is that persons who feign mental illness will not attempt to fake a particular disorder, but will be content to fabricate non-specific and possibly global psychiatric impairment. We tested the effectiveness of the Structured Interview of Reported Symptoms (SIRS) to detect feigning of three diagnostic groupings: schizophrenia, mood disorders, and PTSD on 45 psychologically knowledgeable correctional residents. We found that the SIRS maintained its powers of discrimination with respect to clinical samples. Similar research on faking specific disorders is needed on the MMPI-2 and other psychological measures.