A systematic review of the utility of continuous performance tests among adults with ADHD

OBJECTIVE

The clinical utility of continuous performance tests (CPTs) among adults with attention-deficit/hyperactivity disorder (ADHD) has increasingly been brought under question. Therefore, the objective of this study was to systematically review the literature to investigate the clinical utility of various commercially available CPTs, including the Conner's Continuous Performance Test (CCPT), Test of Variables of Attention (TOVA), Gordon Diagnostic System (GDS), and Integrated Visual and Auditory Continuous Performance Test (IVA) in the adult ADHD population.

METHODS

This systematic review followed the a priori PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Articles were gathered from PsycINFO, PsycARTICLES, Academic Search Complete, and Google Scholar on 11 April 2022. Sixty-nine articles were included in the final review. Risk of bias was assessed using the National Institute of Health Quality Assessment Took for Observational Cohort and Cross-Sectional Studies.

RESULTS

Most articles demonstrated high risk of bias, and there was substantial heterogeneity across studies. Overall, the reviewed CPTs appeared to have limited diagnostic utility and classification accuracy. Although many studies showed differing scores between adults with ADHD and comparison groups, findings were not consistent. Characteristics of CPT performances among adults with ADHD were mixed, with little consistency and no evidence of a clear profile of performances; however, CCPT commission errors appeared to have the most utility when used a treatment or experimental outcome measure, compared to other CCPT scores.

CONCLUSION

Overall, CPTs should not be used in isolation as a diagnostic test but may be beneficial when used as a component of a comprehensive assessment.

Comparing embedded performance validity indicators within the WAIS-IV Letter-Number sequencing subtest to Reliable Digit Span among adults referred for evaluation of attention-deficit/hyperactivity disorder

Objectives: This study investigated the Wechsler Adult Intelligence Scale-Fourth Edition Letter-Number Sequencing (LNS) subtest as an embedded performance validity indicator among adults undergoing an attention-deficit/hyperactivity disorder (ADHD) evaluation, and its potential incremental value over Reliable Digit Span (RDS). Method: This cross-sectional study comprised 543 adults who underwent neuropsychological evaluation for ADHD. Patients were divided into valid (n = 480) and invalid (n = 63) groups based on multiple criterion performance validity tests. Results: LNS total raw scores, age-corrected scaled scores, and age- and education-corrected T-scores demonstrated excellent classification accuracy (area under the curve of .84, .83, and .82, respectively). The optimal cutoff for LNS raw score (≤16), age-corrected scaled score (≤7), and age- and education-corrected T-score (≤36) yielded .51 sensitivity and .94 specificity. Slightly lower sensitivity (.40) and higher specificity (.98) was associated with a more conservative T-score cutoff of ≤33. Multivariate models incorporating both LNS and RDS improved classification accuracy (area under the curve of .86), and LNS scores explained a significant but modest proportion of variance in validity status above and beyond RDS. Chaining LNS T-score of ≤33 with RDS cutoff of ≤7 increased sensitivity to .69 while maintaining ≥.90 specificity. Conclusions: Findings provide preliminary evidence for the criterion and construct validity of LNS as an embedded validity indicator in ADHD evaluations. Practitioners are encouraged to use LNS T-score cutoff of ≤33 or ≤36 to assess the validity of obtained test data. Employing either of these LNS cutoffs with RDS may enhance the detection of invalid performance.

EMG measured reaction time as a predictor of invalid symptom report in psychosomatic patients

Background: Symptom validity tests (SVTs) and performance validity tests (PVTs) are important tools in sociomedical assessments, especially in the psychosomatic context where diagnoses mainly depend on clinical observation and self-report measures. This study examined the relationship between reaction times (RTs) and scores on the Structured Inventory of Malingered Symptomatology (SIMS). It was proposed that slower RTs and larger standard deviations of reaction times (RTSDs) would be observed in participants who scored above the SIMS cut-off (>16). Methods: Direct surface electromyography (EMG) was used to capture RTs during a computer-based RT test in 152 inpatients from a psychosomatic rehabilitation clinic in Germany. Correlation analyses and Mann-Whitney U were used to examine the relationship between RTs and SIMS scores and to assess the potential impact of covariates such as demographics, medical history, and vocational challenges on RTs. Therefore, dichotomized groups based on each potential covariate were compared. Results: Significantly longer RTs and larger RTSDs were found in participants who scored above the SIMS cut-off. Current treatment with psychopharmacological medication, diagnosis of depression, and age had no significant influence on the RT measures. However, work-related problems had a significant impact on RTSDs. Conclusion: There was a significant relationship between longer and more inconsistent RTs and indicators of exaggerated or feigned symptom report on the SIMS in psychosomatic rehabilitation inpatients. Findings from this study provide a basis for future research developing a new RT-based PVT.

Differentiating Performance on the Connors Continuous Performance Test (CPT-3) as a Function of Comorbid Internalizing Psychopathology

OBJECTIVE

Internalizing psychopathology commonly co-occurs with attention-deficit/hyperactivity disorder (ADHD). Attention concerns are present in both ADHD and internalizing disorders, yet the neuropsychological functioning of those with comorbid ADHD and internalizing psychopathology is underexamined.

METHOD

This study compared Conners' Continuous Performance Test-Third Edition (CPT-3) profiles across ADHD (n = 141), internalizing psychopathology (n = 78), and comorbid (ADHD/internalizing psychopathology; n = 240) groups.

RESULTS

Compared to the internalizing psychopathology group, the comorbid group had higher mean T-scores on CPT-3 indices indicative of inattentiveness and impulsivity and more clinically elevated T-scores (T>60) on indices measuring inattentiveness and impaired sustained attention. Patients in the comorbid group were also more likely to have abnormal overall CPT-3 profiles (>2 elevated T-scores) than the ADHD and psychopathology only groups.

CONCLUSION

Patients with comorbid ADHD/internalizing psychopathology may evidence a more impaired attentional performance on the CPT-3, which could aid in more tailored treatment planning.

Multivariate models provide an effective psychometric solution to the variability in classification accuracy of D-KEFS Stroop performance validity cutoffs

ObjectiveThe study was designed to expand on the results of previous investigations on the D-KEFS Stroop as a performance validity test (PVT), which produced diverging conclusions. Method The classification accuracy of previously proposed validity cutoffs on the D-KEFS Stroop was computed against four different criterion PVTs in two independent samples: patients with uncomplicated mild TBI (n = 68) and disability benefit applicants (n = 49). Results Age-corrected scaled scores (ACSSs) ≤6 on individual subtests often fell short of specificity standards. Making the cutoffs more conservative improved specificity, but at a significant cost to sensitivity. In contrast, multivariate models (≥3 failures at ACSS ≤6 or ≥2 failures at ACSS ≤5 on the four subtests) produced good combinations of sensitivity (.39-.79) and specificity (.85-1.00), correctly classifying 74.6-90.6% of the sample. A novel validity scale, the D-KEFS Stroop Index correctly classified between 78.7% and 93.3% of the sample. Conclusions A multivariate approach to performance validity assessment provides a methodological safeguard against sample- and instrument-specific fluctuations in classification accuracy, strikes a reasonable balance between sensitivity and specificity, and mitigates the invalid before impaired paradox.

Conner's Continuous Performance Test and Adult ADHD: A Systematic Literature Review

OBJECTIVE

ADHD is a neurodevelopmental disorder affecting millions of adults worldwide. Continuous performance tests (CPTs) are widely used as assessment and diagnostic tools; however, their use in diagnosing undiagnosed ADHD in adults has been questioned due to their lack of specificity and sensitivity. This review sought to outline relevant findings concerning the diagnostic utility of the Conner's Continuous Performance Test (CCPT) in adults.

METHOD

This systematic review followed the a priori guide outlined by the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Articles were gathered from PsycINFO, PsycArticles, Cochrane, Scopus, Google Scholar, and PubMed.

RESULTS

Thirty-five articles were reviewed and analyzed. Most articles reviewed used outpatient and university populations. Moderate reliability, subpar discriminant and ecological validity, and mixed sensitivity and specificity were noted.

CONCLUSION

The results of this review lend support to previous critiques of the CCPT's diagnostic and utility as a treatment measure.

Failing The b Test: The influence of cutoff scores and criterion group approaches in a sample of adults referred for psychoeducational evaluation

OBJECTIVE

Previous research has shown that both criterion grouping approaches and cutoff scores can impact PVT classification accuracy statistics. This study aimed to examine the influence of cutoff scores and criterion grouping approaches on The b Test, a measure designed to identify feigned impairment in visual scanning, processing speed, and letter identification.

METHOD

Two hundred ninety-seven adults referred for psychoeducational testing were included with the majority of individuals seeking academic accommodations (n = 215). Cutoff scores of ≥82, ≥90, and ≥120 were utilized along with two different criterion group approaches, 0 PVT failures vs. ≥2 PVT failures and 0 PVT failures versus ≥ 1 PVT failures.

RESULTS

Failure rates for The b Test in the overall sample ranged from 12.5% to 16.2%. Subgroup analyses in those referred specifically for ADHD revealed failure rates for The b Test ranging from 10.5% to 14.2%. ROC curves within the full sample and ADHD subsample demonstrated significant AUCs utilizing both criterion group approaches (AUC = .66 - .78). Sensitivity and specificity varied as a function of criterion group approach and cutoff score, with 0 PVT failures vs. ≥ 2 PVT failures resulting in the greatest sensitivity when maximizing specificity at ≥.90 in the full sample and ADHD sample.

CONCLUSIONS

The results demonstrate that criterion approaches and cutoff scores impact classification accuracy of The b Test with 0 PVT vs. ≥ 2 PVT failures demonstrating the greatest classification accuracy. Special considerations should be made with regard to clinical decision making in the context of psychoeducational evaluations given that a large portion of individuals seeking accommodations fail only one PVT. Limitations of this study are also discussed.

Malingering and Stimulant Medications Abuse, Misuse and Diversion

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that interferes with multiple aspects of daily functioning. Malingering or feigning of symptoms can be a major challenge during ADHD assessment. Stimulant medication abuse, misuse and diversion may constitute another challenge during management. A literature search of the past 15 years on the topic continued to suggest that there are several reasons for malingering and faking ADHD symptoms. Some of the reasons include the intent to obtain prescriptions for stimulant medications for performance enhancement, to gain access to additional school services and accommodations, to use recreationally and to sell as a street drug. In some countries, patients may receive additional tax or student loan benefits. Several researchers suggested that self-report rating measures are easily simulated by patients without ADHD. They concluded that no questionnaire has proved sufficiently robust against false positives. Some clinical factors that may suggest malingering during the ADHD assessment are highlighted and some available tests to detect malingering are discussed.

SPECT Functional Neuroimaging Distinguishes Adult Attention Deficit Hyperactivity Disorder From Healthy Controls in Big Data Imaging Cohorts

Background: The diagnosis of attention deficit hyperactivity disorder (ADHD) relies on history and observation, as no reliable biomarkers have been identified. In this study, we compared a large single diagnosis group of patients with ADHD (combined, inattentive, and hyperactive) to healthy controls using brain perfusion single-photon emission computed tomography (SPECT) imaging to determine specific brain regions which could serve as potential biomarkers to reliably distinguish ADHD. Methods: In a retrospective analysis, subjects (n = 1,135) were obtained from a large multisite psychiatric database, where resting state (baseline) and on-task SPECT scans were obtained. Only baseline scans were analyzed in the present study. Subjects were separated into two groups - Group 1 (n = 1,006) was composed of patients who only met criteria for ADHD with no comorbid diagnoses, while a control group (n = 129) composed of individuals who did not meet criteria for any psychiatric diagnosis, brain injury, or substance use served as a non-matched control. SPECT regions of interests (ROIs) and visual readings were analyzed using binary logistic regression. Predicted probabilities from this analysis were inputted into a Receiver Operating Characteristic analysis to identify sensitivity, specificity, and accuracy. Results: The baseline ROIs and visual readings show significant separations from healthy controls. Sensitivity of the visual reads was 100% while specificity was >97%. The sensitivity and specificity of the post-hoc ROI analysis were both 100%. Decreased perfusion was primarily seen in the orbitofrontal cortices, anterior cingulate gyri, areas of the prefrontal cortices, basal ganglia, and temporal lobes. In addition, ROI analysis revealed some unexpected areas with predictive value in distinguishing ADHD, such as cerebellar subregions and portions of the temporal lobes. Conclusions: Brain perfusion SPECT distinguishes adult ADHD patients without comorbidities from healthy controls. Areas which were highly significantly different from control and thus may serve as biomarkers in baseline SPECT scans included: medial anterior prefrontal cortex, left anterior temporal lobe, and right insular cortex. Future studies of these potential biomarkers in ADHD patients with comorbidities are warranted.

What can we learn about performance validity from TOVA response profiles?

Given the functional impairments associated with Attention Deficit/Hyperactivity Disorder (AD/HD), a valid diagnosis is important. However, particularly when carried out in adulthood, the diagnostic process can be challenging and is complicated by conclusive evidence that a proportion of individuals referred for evaluation of AD/HD exaggerate or feign their symptoms. Relatively few methods, however, exist to identify such feigning. While continuous performance tests (CPTs) may provide useful information regarding performance validity, the question remains as to whether there are consistent patterns of exaggeration demonstrated by those feigning AD/HD. Thus, this study used cluster analysis to determine whether valid and reliable performance clusters would emerge based on CPT performance. Using archival data from a university-based AD/HD screening clinic, we investigated the performance of 305 adults on the Test of Variables of Attention (TOVA). Three profiles emerged, including one cluster who demonstrated exceptionally low performance on the TOVA, exceptionally high reports of AD/HD symptomology, and higher rates of failure on symptom and performance validity tests. The implication from our analysis is that this group most likely represents individuals who were exaggerating or magnifying their difficulties. The results reaffirm previous research showing that performance profiles on a continuous performance test can be used as an indicator of credible performance.

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.

Diagnosing ADHD in Adults: An Examination of the Discriminative Validity of Neuropsychological Tests and Diagnostic Assessment Instruments

OBJECTIVE

The objective of this study is to investigate the discriminative validity of neuropsychological tests and diagnostic assessment instruments in diagnosing adult ADHD in a clinical psychiatric population.

METHOD

Of 108 patients, 60 were diagnosed with ADHD. The Diagnostic Interview for ADHD in adults (DIVA 2.0) and Adult ADHD Self-Report Scale (ASRS) v.1.1 together with eight neuropsychological tests were investigated.

RESULTS

All instruments showed poor discriminative ability except for the DIVA, which showed a relatively good ability to discriminate between the groups (sensitivity = 90.0; specificity = 72.9). A logistic regression analysis model with the DIVA and measures of inattention, impulsivity, and activity from continuous performance tests (CPTs) showed a sensitivity of 90.0 and a specificity of 83.3.

CONCLUSION

Neuropsychological tests have a poor ability to discriminate between patients diagnosed with ADHD and patients not diagnosed with ADHD, but variables from CPT tests can contribute to increasing the specificity by 10% if used in combination with the DIVA.

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

OBJECTIVE

To compare ADHD patients who failed a symptom validity test with those who passed the test to explore whether there are signs of negative response bias on group level.

METHOD

In our outpatient department, 196 adults were diagnosed with ADHD using a comprehensive diagnostic strategy featuring a detailed clinical history, clinical interview, observer rating, several self-rating scales, and neuropsychological attention tests. The Amsterdam Short Term Memory Test (AKGT) was applied as a symptom validity measure.

RESULTS

Sixty-three patients (32.1%) scored below the AKGT cutoff level. The two groups did not significantly differ regarding self-report and observer ratings. Those who failed the AKGT had higher reaction time variabilities in selective, auditory and visual divided attention, and higher omission errors in sustained attention.

CONCLUSION

We found no strong indicators for negative response bias in ADHD patients who failed a symptom validity test. New measures and approaches to detect feigned ADHD should be developed.

Cognitive persistence: Development and validation of a novel measure from the Wisconsin Card Sorting Test

The Wisconsin Card Sorting Test (WCST) has long been used as a neuropsychological assessment of executive function abilities, in particular, cognitive flexibility or "set-shifting". Recent advances in scoring the task have helped to isolate specific WCST performance metrics that index set-shifting abilities and have improved our understanding of how prefrontal and parietal cortex contribute to set-shifting. We present evidence that the ability to overcome task difficulty to achieve a goal, or "cognitive persistence", is another important prefrontal function that is characterized by the WCST and that can be differentiated from efficient set-shifting. This novel measure of cognitive persistence was developed using the WCST-64 in an adult lifespan sample of 230 participants. The measure was validated using individual variation in cingulo-opercular cortex function in a sub-sample of older adults who had completed a challenging speech recognition in noise fMRI task. Specifically, older adults with higher cognitive persistence were more likely to demonstrate word recognition benefit from cingulo-opercular activity. The WCST-derived cognitive persistence measure can be used to disentangle neural processes involved in set-shifting from those involved in persistence.

Word Memory Test Performance Across Cognitive Domains, Psychiatric Presentations, and Mild Traumatic Brain Injury

Objective

The current study addressed two aims: (i) determine how Word Memory Test (WMT) performance relates to test performance across numerous cognitive domains and (ii) evaluate how current psychiatric disorders or mild traumatic brain injury (mTBI) history affects performance on the WMT after excluding participants with poor symptom validity.

Method

Participants were 235 Iraq and Afghanistan-era veterans (Mage = 35.5) who completed a comprehensive neuropsychological battery. Participants were divided into two groups based on WMT performance (Pass = 193, Fail = 42). Tests were grouped into cognitive domains and an average z-score was calculated for each domain.

Results

Significant differences were found between those who passed and those who failed the WMT on the memory, attention, executive function, and motor output domain z-scores. WMT failure was associated with a larger performance decrement in the memory domain than the sensation or visuospatial-construction domains. Participants with a current psychiatric diagnosis or mTBI history were significantly more likely to fail the WMT, even after removing participants with poor symptom validity.

Conclusions

Results suggest that the WMT is most appropriate for assessing validity in the domains of attention, executive function, motor output and memory, with little relationship to performance in domains of sensation or visuospatial-construction. Comprehensive cognitive batteries would benefit from inclusion of additional performance validity tests in these domains. Additionally, symptom validity did not explain higher rates of WMT failure in individuals with a current psychiatric diagnosis or mTBI history. Further research is needed to better understand how these conditions may affect WMT performance.

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.

Assessment of Performance Validity Using Embedded Saccadic and Manual Indices on a Continuous Performance Test

OBJECTIVE

In addition to manual (i.e., "button press") metrics, oculomotor metrics demonstrate considerable promise as tools for detecting invalid responding in neurocognitive assessment. This study was conducted to evaluate saccadic and manual metrics from a computerized continuous performance test as embedded indices of performance validity.

METHOD

Receiver operating characteristic analyses, logistic regressions, and ANOVAs were performed to evaluate saccadic and manual metrics in classification of healthy adults instructed to feign deficits ("Fake Bad" group; n = 24), healthy adults instructed to perform their best ("Best Effort" group; n = 26), and adults with a history of mild traumatic brain injury (TBI) who passed a series of validity indices ("mTBI-Pass" group; n = 19).

RESULTS

Several saccadic and manual metrics achieved outstanding classification accuracy between Fake Bad versus Best Effort and mTBI-Pass groups, including variability (consistency) of saccadic and manual response time (RT), saccadic commission errors, and manual omission errors. Very large effect sizes were obtained between Fake Bad and Best Effort groups (Cohen's d range: 1.89-2.90; r range: .75-.78) as well as between Fake Bad and mTBI-Pass groups (Cohen's d range: 1.32-2.21; r range: .69-.71). The Fake Bad group consistently had higher saccadic and manual RT variability, more saccadic commission errors, and more manual omission errors than the Best Effort and mTBI-Pass groups.

CONCLUSIONS

These findings are the first to demonstrate that eye movements can be used to detect invalid responding in neurocognitive assessment. These results also provide compelling evidence that concurrently measured saccadic and manual metrics can detect invalid responding with high levels of sensitivity and specificity.

Misuse of Methylphenidate

This chapter reviews methylphenidate misuse, abuse, dependence, diversion, and malingering associated with its use as a prescription medication for attention-deficit/hyperactivity disorder and the nonmedical use linked to its stimulant effects. Methylphenidate-induced regional elevations in brain dopamine appear to be integral to both efficacy in attention-deficit/hyperactivity disorder and potential for abuse, raising potential concerns for drug safety and prescription drug diversion costs associated with nonmedical use. Regardless, methylphenidate is an important treatment option, and detecting malingering for the purpose of illicit access to methylphenidate for subsequent misuse or diversion is a difficult challenge. Also discussed are the effects of methylphenidate in patients with comorbid substance use disorder and the potential linkage of methylphenidate use with subsequent substance abuse. The current data suggest that methylphenidate misuse and diversion are common health-care problems with a stimulant prescription drug diversion prevalence of approximately 5-10 % of high school students and 5-35 % of college students. The effectiveness and speed of action of methylphenidate are deemed desirable to enhance attention and focus performance for activities such as studying for exams, but methylphenidate is also misused recreationally. These data suggest a need for close screening and therapeutic monitoring of methylphenidate use in the treatment of attention-deficit/hyperactivity disorder.

"Why is this so hard?" A review of detection of malingered ADHD in college students

OBJECTIVE

The purpose of this article is to review studies that have investigated malingered ADHD in college students and offer recommendations for assessing effort in clinical evaluations of ADHD in college students.

METHOD

This article identified and summarized nineteen peer-reviewed, empirical studies published between 2002 and 2011 that investigated malingered ADHD in college students.

RESULTS

Few of the measures examined proved useful for detecting malingered ADHD. Most self-report questionnaires were not sensitive to malingering. While there is some variability in the usefulness of neuropsychological test failure, profiles between malingerers and individuals with ADHD are too similar to confidently detect malingered ADHD. Failure of three or more symptom validity tests proved most useful at detecting malingered ADHD.

CONCLUSION

This review suggests that there is substantial need for measures designed specifically for detecting malingered ADHD. Simulators are able to produce plausible profiles on most tools used to diagnose ADHD.

Quantitative and subjective behavioural aspects in the assessment of attention-deficit hyperactivity disorder (ADHD) in adults

BACKGROUND

Self-rating scales and cognitive tests are instruments used in the assessment of attention-deficit hyperactivity disorder (ADHD). However, few studies have examined the differential validity of these kinds of instruments in psychiatric samples.

AIMS

To examine the discriminative validity of two self-report scales (ADHD Self-Report Scale [ASRS v.1.1], Current Symptom Scale [CSS]) and a continuous performance test with measures of motor activity (QBTest Plus).

METHODS

The interrelation between the instruments, and their abilities to differentiate between patients with an ADHD diagnosis and non-ADHD patients referred for psychiatric assessment were examined in a naturalistic sample of 61 adult patients.

RESULTS

The area under the receiver operating characteristic curve (AUC) for the dichotomized versions of the test variables in all tests ranged from 0.61 to 0.71. The ASRS and CSS exhibited sensitivity of 90.2% and 85.4%, and specificity of 35.0% and 40.0%, respectively. Variables from the QBTest Plus showed the opposite result for the variables QBImpulsivity and QBInattention, with sensitivity of 58.5% and 36.3% and specificity of 80.0% and 100.0%. Sensitivity and specificity of QBActivity were 68.3% and 65.0%, respectively. A stepwise discriminant function analysis showed that two variables from the QBTest Plus--QBInattention and QBActivity--accounted for 22.8% of the between-group variability, with the strongest predictor being QBInattention. The function yielded an overall correct classification of 72.1%. The classification correctly identified 87.8% of patients diagnosed with ADHD and 40.0% of non-ADHD patients.

CONCLUSION

The discriminant validity of self-rating scales and the more objective measure of ADHD symptoms are poor and should be integrated generally with other sources of data.

Detecting suboptimal cognitive effort: classification accuracy of the Conner's Continuous Performance Test-II, Brief Test Of Attention, and Trail Making Test

Many cognitive measures have been studied for their ability to detect suboptimal cognitive effort; however, attention measures have not been extensively researched. The current study evaluated the classification accuracy of commonly used attention/concentration measures, the Brief Test of Attention (BTA), Trail Making Test (TMT), and the Conners' Continuous Performance Test (CPT-II). Participants included 413 consecutive patients who completed a comprehensive neuropsychological evaluation. Participants were separated into two groups, identified as either unbiased responders or biased responders as determined by performance on the TOMM. Based on Mann-Whitney U results, the two groups differed significantly on all attentional measures. Classification accuracy of the BTA (.83), CPT-II omission errors (OE; .76) and TMT B (.75) were acceptable; however, classification accuracy of CPT-II commission errors (CE; .64) and TMT A (.62) were poor. When variables were combined in different combinations, sensitivity did not significantly increase. Results indicated for optimal cut-off scores, sensitivity ranged from 48% to 64% when specificity was at least 85%. Given that sensitivity rates were not adequate, there remains a need to utilize highly sensitive measures in addition to these embedded measures. Results were discussed within the context of research promoting the need for multiple measures of cognitive effort.

Using symptom validity tests to detect malingered ADHD in college students

Recently there has been growing concern that college students may feign symptoms of ADHD in order to obtain academic accommodations and stimulant medication. Unfortunately research has only begun to validate detection tools for malingered ADHD. The present study cross-validated the results of Sollman, Ranseen, and Berry (2010) on the efficacy of several symptom validity tests for detection of simulated ADHD among college students. Undergraduates with a history of diagnosed ADHD were randomly assigned either to respond honestly or exaggerate symptoms, and were compared to undergraduates with no history of ADHD or other psychiatric disorders who were also randomly assigned to respond honestly or feign symptoms of ADHD. Similar to Sollman et al. (2010) and other recent research on feigned ADHD, several symptom validity tests, including the Test of Memory Malingering (TOMM), Letter Memory Test (LMT), Digit Memory Test (DMT), Nonverbal Medical Symptom Validity Test (NV-MSVT), and the b Test were reasonably successful at discriminating feigned and genuine ADHD. When considered as a group, the criterion of failure of 2 or more of these SVTs had a sensitivity of. 475 and a specificity of 1.00.