Faking ADHD? Symptom Validity Testing and Its Relation to Self-Reported, Observer-Reported Symptoms, and Neuropsychological Measures of Attention in Adults With ADHD

The Impact of Adverse Childhood Experiences on Symptom and Performance Validity Tests Among a Multiracial Sample Presenting for ADHD Evaluation

OBJECTIVE

Adverse childhood experiences (ACEs) are commonly reported in individuals presenting for attention-deficit hyperactivity disorder (ADHD) evaluation. Performance validity tests (PVTs) and symptom validity tests (SVTs) are essential to ADHD evaluations in young adults, but extant research suggests that those who report ACEs may be inaccurately classified as invalid on these measures. The current study aimed to assess the degree to which ACE exposure differentiated PVT and SVT performance and ADHD symptom reporting in a multi-racial sample of adults presenting for ADHD evaluation.

METHOD

This study included 170 adults referred for outpatient neuropsychological ADHD evaluation who completed the ACE Checklist and a neurocognitive battery that included multiple PVTs and SVTs. Analysis of variance was used to examine differences in PVT and SVT performance among those with high (≥4) and low (≤3) reported ACEs.

RESULTS

Main effects of the ACE group were observed, such that high ACE group reporting demonstrated higher scores on SVTs assessing ADHD symptom over-reporting and infrequent psychiatric and somatic symptoms on the Minnesota Multiphasic Personality Inventory-2-Restructured Form. Conversely, no significant differences emerged in total PVT failures across ACE groups.

CONCLUSIONS

Those with high ACE exposure were more likely to have higher scores on SVTs assessing over-reporting and infrequent responses. In contrast, ACE exposure did not affect PVT performance. Thus, ACE exposure should be considered specifically when evaluating SVT performance in the context of ADHD evaluations, and more work is needed to understand factors that contribute to different patterns of symptom reporting as a function of ACE exposure.

Cognitive Underperformance in a Mixed Neuropsychiatric Sample at Diagnostic Evaluation of Adult ADHD

(1) Background: The clinical assessment of attention-deficit/hyperactivity disorder (ADHD) in adulthood is known to show non-trivial base rates of noncredible performance and requires thorough validity assessment. (2) Objectives: The present study estimated base rates of noncredible performance in clinical evaluations of adult ADHD on one or more of 17 embedded validity indicators (EVIs). This study further examines the effect of the order of test administration on EVI failure rates, the association between cognitive underperformance and symptom overreporting, and the prediction of cognitive underperformance by clinical information. (3) Methods: A mixed neuropsychiatric sample (N = 464, ADHD = 227) completed a comprehensive neuropsychological assessment battery on the Vienna Test System (VTS; CFADHD). Test performance allows the computation of 17 embedded performance validity indicators (PVTs) derived from eight different neuropsychological tests. Further, all participants completed several self- and other-report symptom rating scales assessing depressive symptoms and cognitive functioning. The Conners' Adult ADHD Rating Scale and the Beck Depression Inventory-II were administered to derive embedded symptom validity measures (SVTs). (4) Results and conclusion: Noncredible performance occurs in a sizeable proportion of about 10% up to 30% of individuals throughout the entire battery. Tests for attention and concentration appear to be the most adequate and sensitive for detecting underperformance. Cognitive underperformance represents a coherent construct and seems dissociable from symptom overreporting. These results emphasize the importance of performing multiple PVTs, at different time points, and promote more accurate calculation of the positive and negative predictive values of a given validity measure for noncredible performance during clinical assessments. Future studies should further examine whether and how the present results stand in other clinical populations, by implementing rigorous reference standards of noncredible performance, characterizing those failing PVT assessments, and differentiating between underlying motivations.

Attention and impulsivity assessment using virtual reality games

The assessment of cognitive functions is mainly based on standardized neuropsychological tests, widely used in various fields such as personnel recruitment, education, or health. This paper presents a virtual reality game that allows collecting continuous measurements of both the performance and behaviour of the subject in an immersive, controllable, and naturalistic experience. The application registers variables related to the user's eye movements through the use of virtual reality goggles, as well as variables of the game performance. We study how virtual reality can provide data to help predict scores on the Attention Control Scale Test and the Barratt Impulsiveness Scale. We design the application and test it with a pilot group. We build a random forest regressor model to predict the attention and impulsivity scales' total score. When evaluating the performance of the model, we obtain a positive correlation with attention (0.434) and with impulsivity (0.382). In addition, our model identified that the most significant variables are the time spent looking at the target or at distractors, the eye movements variability, the number of blinks and the pupil dilation in both attention and impulsivity. Our results are consistent with previous results in the literature showing that it is possible to use data collected in virtual reality to predict the degree of attention and impulsivity.

Symptom and performance validity in samples of adults at clinical evaluation of ADHD: a replication study using machine learning algorithms

INTRODUCTION

Research has shown non-trivial base rates of noncredible symptom report and performance in the clinical evaluation of attention-deficit/hyperactivity disorder (ADHD) in adulthood. The goal of this study is to estimate and replicate base rates of symptom and performance validity test failure in the clinical evaluation of adult ADHD and derive prediction models based on routine clinical measures.

METHODS

This study reuses data of a previous publication of 196 adults seeking ADHD assessment and replicates the findings on an independent sample of 700 adults recruited in the same referral context. Measures of symptom and performance validity (one SVT, two PVTs) were applied to estimate base rates. Prediction models were developed using machine learning.

RESULTS

Both samples showed substantial rates of noncredible symptom report (one SVT failure: 35.7% - 36.6%), noncredible test performance (one PVT failure: 32.1% - 49.3%; two PVT failures: 18.9% - 27.3%), or both (each one SVT and PVT failure: 13.3% - 22.4%; one SVT and two PVT failures: 9.7% - 13.7%). Machine learning algorithms resulted in generally moderate to weak prediction models, with advantages of the reused sample compared to the independent replication sample. Associations between measures of symptom and performance validity were negligible to small.

CONCLUSIONS

This study highlights the necessity to include measures of symptom and performance validity in the clinical evaluation of adult ADHD. Further, this study demonstrates the difficulty to characterize the group failing symptom or performance validity assessment.

Cross-Validation of Multiple WAIS-IV Digit Span Embedded Performance Validity Indices Among a Large Sample of Adult Attention Deficit/Hyperactivity Disorder Clinical Referrals

This study investigated the utility of four WAIS-IV Digit Span (DS) indices (traditional Reliable Digit Span [RDS], RDS-Working Memory [RDS-WM], RDS-Revised [RDS-R], and DS Age-Corrected Scaled Score [ACSS]) as embedded performance validity tests (PVTs) among a sample of 342 consecutive adults referred for neuropsychological evaluation of ADHD. All DS indices had acceptable classification accuracy (areas under the curve: .73–.76) for detecting invalid performance with optimal cut-scores of RDS ≤7 (35% sensitivity/93% specificity), RDS-WM ≤7 (56% sensitivity/86% specificity), RDS-R ≤12 (48% sensitivity/85% specificity), and ACSS ≤7 (46% sensitivity/87% specificity). Although all indices were able to detect invalid performance, DS indices incorporating the more complex working memory trials of the task yielded the best accuracy for identification of invalid test performance among adults referred for ADHD evaluation.

Detection of Feigned ADHD Using the MOXO-d-CPT

Objective: The objective of this study was to assess the MOXO-d-CPT utility in detecting feigned ADHD and establish cutoffs with adequate specificity and sensitivity. Method: The study had two phases. First, using a prospective design, healthy adults who simulated ADHD were compared with healthy controls and ADHD patients who performed the tasks to the best of their ability (n = 47 per group). Participants performed the MOXO-d-CPT and an established performance validity test (PVT). Second, the MOXO-d-CPT classification accuracy, employed in Phase 1, was retrospectively compared with archival data of 47 ADHD patients and age-matched healthy controls. Results: Simulators performed significantly worse on all MOXO-d-CPT indices than healthy controls and ADHD patients. Three MOXO-d-CPT indices (attention, hyperactivity, impulsivity) and a scale combining these indices showed adequate discriminative capacity. Conclusion: The MOXO-d-CPT showed promise for the detection of feigned ADHD and, pending replication, can be employed for this aim in clinical practice and ADHD research.

Non-credible symptom report in the clinical evaluation of adult ADHD: development and initial validation of a new validity index embedded in the Conners' adult ADHD rating scales

As attention-deficit/hyperactivity disorder (ADHD) is a feasible target for individuals aiming to procure stimulant medication or accommodations, there is a high clinical need for accurate assessment of adult ADHD. Proven falsifiability of commonly used diagnostic instruments is therefore of concern. The present study aimed to develop a new, ADHD-specific infrequency index to aid the detection of non-credible self-report. Disorder-specific adaptations of four detection strategies were embedded into the Conners’ Adult ADHD Rating Scales (CAARS) and tested for infrequency among credible neurotypical controls (n = 1001) and credible adults with ADHD (n = 100). The new index’ ability to detect instructed simulators (n = 242) and non-credible adults with ADHD (n = 22) was subsequently examined using ROC analyses. Applying a conservative cut-off score, the new index identified 30% of participants instructed to simulate ADHD while retaining a specificity of 98%. Items assessing supposed symptoms of ADHD proved most useful in distinguishing genuine patients with ADHD from simulators, whereas inquiries into unusual symptom combinations produced a small effect. The CAARS Infrequency Index (CII) outperformed the new infrequency index in terms of sensitivity (46%), but not overall classification accuracy as determined in ROC analyses. Neither the new infrequency index nor the CII detected non-credible adults diagnosed with ADHD with adequate accuracy. In contrast, both infrequency indices showed high classification accuracy when used to detect symptom over-report. Findings support the new indices’ utility as an adjunct measure in uncovering feigned ADHD, while underscoring the need to differentiate general over-reporting from specific forms of feigning.

A comparison of the self-report patterns of analog versus real-world malingerers of attention deficit hyperactivity disorder

Much of what we know about malingering of attention deficit hyperactivity disorder (ADHD) has been learned from the performance of analog malingerers, typically first-year psychology students given credit for study participation. It is not clear, however, whether their performance is similar to that found in actual clinical settings. Indeed, past research suggests that analog malingerers may overexaggerate deficits relative to real-world malingerers, making them easier to identify in controlled studies. The purpose of the current study was, therefore, to compare the performance of analog malingers to post-secondary students strongly suspected of malingering ADHD on a self-report measure of ADHD symptoms. Their scores were, in turn, compared to those returned by students with genuine ADHD and clinical controls. Results demonstrated that, apart from analog subjects overexaggerating symptoms of hyperactivity, few differences exist between the scores returned by analog malingerers relative to clinical malingerers. While newly devised symptom validity measures show promise in identifying malingered ADHD, neither the analog nor the clinical malingers consistently failed these symptom validity scales. Furthermore, a good portion in both malingering groups failed to endorse high levels of ADHD symptoms in general. Clinical implications are discussed.

Use of machine learning to classify adult ADHD and other conditions based on the Conners' Adult ADHD Rating Scales

A reliable diagnosis of adult Attention Deficit/Hyperactivity Disorder (ADHD) is challenging as many of the symptoms of ADHD resemble symptoms of other disorders. ADHD is associated with gambling disorder and obesity, showing overlaps of about 20% with each diagnosis. It is important for clinical practice to differentiate between conditions displaying similar symptoms via established diagnostic instruments. Applying the LightGBM algorithm in machine learning, we were able to differentiate subjects with ADHD, obesity, problematic gambling, and a control group using all 26 items of the Conners' Adult ADHD Rating Scales (CAARS-S: S) with a global accuracy of .80; precision (positive predictive value) ranged between .78 (gambling) and .92 (obesity), recall (sensitivity) between .58 for obesity and .87 for ADHD. Models with the best 5 and best 10 items resulted in less satisfactory fits. The CAARS-S seems to be a promising instrument to be applied in clinical practice also for multiclassifying disorders displaying symptoms resembling ADHD.

Decision making of forensic psychiatric inpatients deemed incompetent to stand trial

This study examined decision making and its correlates among forensic psychiatric inpatients deemed incompetent to stand trial (IST). This study utilized archival data (n = 41; Mean Age = 44.27, SD = 15.89, 79.1% Male; 34.1% Caucasian). Decision making was measured using the Iowa Gambling Task (IGT), which is purported to simulate real-life decision making. Correlates included cognitive functioning, psychiatric symptom severity, and impulsivity. Participants selected more frequently from disadvantageous decks, which yield larger immediate monetary gains with a larger long-term monetary losses (Mean NET = -9.51, SD = 26.70), but avoided decks yielding frequent monetary losses (Mean GLF = 10.10, SD = 26.70). Consistently, participants selected most frequently from a deck yielding the most immediate monetary gains and the least frequent monetary losses compared to other decks (ps < 0.05). Based upon their selections, participants lost a significant amount of money (M = -$1,493.22, SD = $1,182.26). IGT outcomes were differentially associated with cognitive functioning (rs = -0.26 to 0.47), psychiatric symptom severity (rs = -0.41 to 0.37), and impulsivity (rs = -0.47 to 0.28; all ps = 0.003-0.98). Findings can guide future research, as well as guide competency restoration and decision-making interventions, for this population.

Diagnosing Attention-Deficit/Hyperactivity Disorder (ADHD) in young adults: A qualitative review of the utility of assessment measures and recommendations for improving the diagnostic process

Objective: Identify assessment measures that augment the clinical interview and improve the diagnostic accuracy of adult ADHD assessment.Method: The sometimes limited research literatures concerning the diagnostic efficacies of the clinical interview, standard and novel ADHD behavior rating scales, performance and symptom validity testing, and cognitive tests are critically reviewed.Results: Based on this qualitative review, both clinical interviews alone and ADHD behavior rating scales alone have adequate sensitivity but poor specificity in diagnosing ADHD. Response validity and symptom validity tests have reasonably good sensitivity and very good specificity in detecting invalid symptom presentation. Cognitive test batteries have inadequate sensitivity and specificity in identifying ADHD. Using cognitive tests in conjunction with behavior rating scales significantly improves the specificity of an assessment battery. Executive function behavior rating scales and functional impairment rating scales are unlikely to improve the diagnostic accuracy of ADHD assessment.Conclusions: Based on this review, key clinical interview questions, behavior rating scales, symptom validity tests, and cognitive tests that have promise to enhance current assessment practices are recommended. These are the authors' personal opinions, not consensus standards, or guidelines promulgated by any organization. These measures are incorporated in a practical, somewhat abbreviated, battery that has the potential to improve clinicians' ability to diagnose adult ADHD.

Emotional dysregulation subgroups in patients with adult Attention-Deficit/Hyperactivity Disorder (ADHD): a cluster analytic approach

Emotion regulation deficits (ERD) are evident in about 34–70% of the adults with ADHD. In contrast to this, they are not considered in the diagnostic criteria of the disorder. In a recent study of our research group using confirmatory factor analysis, we modeled positive and negative emotion as well as emotion regulation skills along with the classical ADHD-core symptoms. We showed that negative affect and the failure to apply adaptive emotion regulation skills were distinct and indicative dimensions in adult ADHD. In this study, we used a person-centered approach based on cluster analysis to subtype patients on the presence or relative absence of ERD. This results in important information to individualize treatment decisions. We found two clusters, with cluster 2 showing high ERD that were associated with higher impairments indicated by depressive mood, negative affect and elevated psychological distress. There were also higher rates of comorbidity in cluster 2 such as somatoform disorders which were associated with ERD. Women were overrepresented in this cluster 2. Neuropsychological variables did not contribute significantly to cluster formation. In conclusion, ADHD in adults is a heterogeneous disorder with specific subgroups that need differential treatment approaches.

Assessing ADHD symptoms in children and adults: evaluating the role of objective measures

BACKGROUND

Diagnostic guidelines recommend using a variety of methods to assess and diagnose ADHD. Applying subjective measures always incorporates risks such as informant biases or large differences between ratings obtained from diverse sources. Furthermore, it has been demonstrated that ratings and tests seem to assess somewhat different constructs. The use of objective measures might thus yield valuable information for diagnosing ADHD. This study aims at evaluating the role of objective measures when trying to distinguish between individuals with ADHD and controls. Our sample consisted of children (n = 60) and adults (n = 76) diagnosed with ADHD and matched controls who completed self- and observer ratings as well as objective tasks. Diagnosis was primarily based on clinical interviews. A popular pattern recognition approach, support vector machines, was used to predict the diagnosis.

RESULTS

We observed relatively high accuracy of 79% (adults) and 78% (children) applying solely objective measures. Predicting an ADHD diagnosis using both subjective and objective measures exceeded the accuracy of objective measures for both adults (89.5%) and children (86.7%), with the subjective variables proving to be the most relevant.

CONCLUSIONS

We argue that objective measures are more robust against rater bias and errors inherent in subjective measures and may be more replicable. Considering the high accuracy of objective measures only, we found in our study, we think that they should be incorporated in diagnostic procedures for assessing ADHD.

The Development of an Embedded Figures Test for the Detection of Feigned Attention Deficit Hyperactivity Disorder in Adulthood

OBJECTIVES

It has been shown that an increasing number of adults deliberately feign attention deficit hyperactivity disorder (ADHD), which demonstrates the need for new tests designed to detect feigned ADHD.

METHODS

An Embedded Figures Test (EFT) was developed for the detection of feigned ADHD in adulthood. EFT performance of 51 adults with ADHD was compared to the performance of 52 matched healthy individuals, as well as to 268 undergraduate students who were randomly allocated in a simulation design to one of four experimental conditions, i.e. a control group, a naïve simulation group, a symptom-coached simulation group or a test-coached simulation group. Furthermore, an independent sample of 11 adults with ADHD as well as a sample of 17 clinicians experienced in the work with adults with ADHD were assessed for further validation of the EFT.

RESULTS

The EFT was relatively easy to perform for both patients with ADHD and healthy comparisons as shown by low error rates and non-significant group differences. However, simulation groups differed from patients with ADHD by significant and large effects. An EFT index for the prediction of feigned ADHD was derived based on logistic regression coefficients. Receiver Operating Characteristics (ROC) demonstrated good classification accuracy of feigned ADHD relative to ADHD (AUC = 94.8%), i.e. high sensitivity (88%) and specificity (90%).

CONCLUSIONS

This study supports the utility of the EFT for the detection of feigned adult ADHD.

Factorial Structure and Validity of the Quantified Behavior Test Plus (Qb+©)

This study investigates the factorial structure and validity of the Quantified Behavior Test Plus (Qb+©), a computerized test to objectively evaluate the three attention deficit/hyperactivity disorder core symptoms, hyperactivity, inattention, and impulsivity, independently. Confirmatory and exploratory factor analyses were conducted with an outpatient sample of 773 subjects ≥12 years old. In a second sample of 297 patients ≥16 years, a multitrait–multimethod analysis was performed to examine concurrent and discriminant validity. The discriminative power of the Qb+ was investigated using a general linear model and logistic regression analysis. The three factorial structure (Hyperactivity, Inattention, Impulsivity) was verified in the confirmatory factor analysis. Fit indices demonstrated a good model fit and factor loadings were almost all moderate to high. In the multitrait–multimethod analysis, the criterion for convergent validity was fulfilled. The discriminant validity of the Qb+ was partially supported. Significant but small gender and age effects were found. In the logistic regression analysis, omission errors and reaction time variability, belonging to the Inattention factor, were able to discriminate between subjects with and without attention deficit/hyperactivity disorder. The internal structure of the Qb+ was verified. Its validity was partially supported. Results regarding discriminative power were mixed.