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The study examined the effect of preparation time and financial incentives on healthy adults' ability to simulate traumatic brain injury (TBI) during neuropsychological evaluation. A retrospective comparison of two TBI simulator group designs: a traditional design employing a single-session of standard coaching immediately before participation (SIM-SC; n = 46) and a novel design that provided financial incentive and preparation time (SIM-IP; n = 49). Both groups completed an ecologically valid neuropsychological test battery that included widely-used cognitive tests and five common performance validity tests (PVTs). Compared to SIM-SC, SIM-IP performed significantly worse and had higher rates of impairment on tests of processing speed and executive functioning (Trails A and B). SIM-IP were more likely than SIM-SC to avoid detection on one of the PVTs and performed somewhat better on three of the PVTs, but the effects were small and non-significant. SIM-IP did not demonstrate significantly higher rates of successful simulation (i.e., performing impaired on cognitive tests with <2 PVT failures). Overall, the rate of the successful simulation was ∼40% with a liberal criterion, requiring cognitive impairment defined as performance >1 SD below the normative mean. At a more rigorous criterion defining impairment (>1.5 SD below the normative mean), successful simulation approached 35%. Incentive and preparation time appear to add limited incremental effect over traditional, single-session coaching analog studies of TBI simulation. Moreover, these design modifications did not translate to meaningfully higher rates of successful simulation and avoidance of detection by PVTs. [ABSTRACT FROM AUTHOR]

Pupillometry provides information about physiological and psychological processes related to cognitive load, familiarity, and deception, and it is outside of conscious control. This study examined pupillary dilation patterns during a performance validity test (PVT) among adults with true and feigned impairment of traumatic brain injury (TBI). Participants were 214 adults in three groups: adults with bona fide moderate to severe TBI (TBI; n = 51), healthy comparisons instructed to perform their best (HC; n = 72), and healthy adults instructed and incentivized to simulate cognitive impairment due to TBI (SIM; n = 91). The Recognition Memory Test (RMT) was administered in the context of a comprehensive neuropsychological battery. Three pupillary indices were evaluated. Two pure pupil dilation (PD) indices assessed a simple measure of baseline arousal (PD-Baseline) and a nuanced measure of dynamic engagement (PD-Range). A pupillary-behavioral index was also evaluated. Dilation-response inconsistency (DRI) captured the frequency with which examinees displayed a pupillary familiarity response to the correct answer but selected the unfamiliar stimulus (incorrect answer). All three indices differed significantly among the groups, with medium-to-large effect sizes. PD-Baseline appeared sensitive to oculomotor dysfunction due to TBI; adults with TBI displayed significantly lower chronic arousal as compared to the two groups of healthy adults (SIM, HC). Dynamic engagement (PD-Range) yielded a hierarchical structure such that SIM were more dynamically engaged than TBI followed by HC. As predicted, simulators engaged in DRI significantly more frequently than other groups. Moreover, subgroup analyses indicated that DRI differed significantly for simulators who scored in the invalid range on the RMT (n = 45) versus adults with genuine TBI who scored invalidly (n = 15). The findings support continued research on the application of pupillometry to performance validity assessment: Overall, the findings highlight the promise of biometric indices in multimethod assessments of performance validity. [ABSTRACT FROM AUTHOR]

Strong associations between civilian posttraumatic stress disorder (PTSD) scales and measures of general psychological distress suggest that the scales are nonspecific to PTSD. Three common PTSD scales were administered to 122 undergraduates who had experienced an emotionally salient, nontraumatic event: a college examination. Results indicated that normal levels of anxiety associated with the examination were positively correlated with scores on the Impact of Event Scale-Revised, Revised Civilian Mississippi Scale, and PTSD Checklist-Civilian Version. Multiple regression analyses indicated that substantial variance in the PTSD scales was accounted for by trait characteristics such as negative and positive affectivity and affect intensity (R2 .29 to .53). Negative affectivity correlated as highly with PTSD measures (r = .46 to .71) as those measures correlated with each other (r = .48 to .65). A high proportion of participants exceeded clinical cutoffs on these measures. The findings suggest that these PTSD scales may be overly sensitive to nontraumatic stressors such as everyday distress and trait characteristics.

Objective: To examine motor vehicle crash frequency and risk factors following moderate-to-severe traumatic brain injury (TBI). Setting: Eight TBI Model Systems sites. Participants: Adults (N = 438) with TBI who required inpatient acute rehabilitation. Design: Cross-sectional, observational design. Main Measures: Driving survey completed at phone follow-up 1 to 30 years after injury. Results: TBI participants reported 1.5 to 2.5 times the frequency of crashes noted in the general population depending on the time frame queried, even when accounting for unreported crashes. Most reported having no crashes; for those who experienced a crash, half of them reported a single incident. Based on logistic regression, age at survey, years since injury, and perception of driving skills were significantly associated with crashes. Conclusion: Compared with national statistics, crash risk is higher following TBI based on self-report. Older age and less time since resuming driving were associated with lower crash risk. When driving was resumed was not associated with crash risk. These results do not justify restricting people from driving after TBI, given that the most who resumed driving did not report experiencing any crashes. However, there is a need to identify and address factors that increase crash risk after TBI. [ABSTRACT FROM AUTHOR]

Examine considerations and perceived barriers to return to driving, and their association with psychosocial outcomes among adults with traumatic brain injury (TBI) who were not driving. 174 adults with moderate-to-severe TBI enrolled in the TBI Model System participated in this cross-sectional study. All participants were drivers prior to their TBI. Outcome measures included the Barriers to Driving Questionnaire, Disability Rating Scale, Patient Health Questionnaire-9, General Anxiety Disorder-7, and Satisfaction With Life Scale. Descriptive analyses examined considerations and barriers to driving, including differences associated with demographic characteristics. Moderation analyses investigated the extent to which disability moderated the relationship between barriers and psychosocial outcomes. Social barriers were the most strongly endorsed domain, whereas physical barriers were endorsed least. The profile of endorsements differed for men and women, and for Black and White participants, on both theoretical considerations in returning to drive and experiences of barriers in doing so. Disability level moderated the relationship between barriers to driving and depression and life satisfaction, but not anxiety. The experience of barriers to driving is differentially associated with psychosocial outcomes among nondriving adults with TBI. Adults with low disability appear to be at risk for distress, even compared to other nondrivers. [ABSTRACT FROM AUTHOR]

Describes a comprehensive, day treatment program conducted in public school classrooms for children with serious emotional disorders (SED) and presents data evaluating program efficacy. At the 9-month follow-up, 50.7% of the sample showed overall symptom reduction, and 27.5% scored below clinical cutoff levels, indicating remission of symptoms to within normal limits. (Contains 80 references and 3 tables.) (GCP)

The nature and magnitude of practice effects on the Wechsler Memory Scale-Revised (D. Wechsler, 1987) were studied with 64 adult college students. The clinically meaningful increase observed across the four test sessions highlights the importance of controlling for practice effects on repeated administration of neuropsychological measures. (SLD)

Abstract Objective Method Results Conclusions This study examined the relationships among functional outcomes and performance on standard-length and abbreviated cognitive screening measures for multiple sclerosis (MS).72 adults with MS underwent neurological examination and cognitive screening. They completed standard-length and abbreviated versions of tests from the Minimal Assessment of Cognitive Function in MS (MACFIMS), the abbreviated aMACFIMS, and the Brief International Cognitive Assessment for MS (BICAMS). Functional outcomes included neurological disability, physical and psychological dysfunction, and employment status.Concordance of impairment classifications was examined between standard-length and abbreviated tests using logistic regression and ROC curve analyses. Overall, the abbreviated test versions showed a broad range of concordance with impairment classifications made using the full-length tests. Processing speed was the strongest correlate of neurological disability and employment status; immediate recall was the strongest predictor of subjective physical dysfunction. Test performance provided unique value toward predicting neurological disability and employment status, but not physical and psychological dysfunction.The findings replicate some support for abbreviated tests in MS assessment, although caveats regarding loss of validity associated with abbreviation remain. The findings extend prior research showing that abbreviated tests of processing speed and immediate recall can provide unique predictive information regarding objective functional outcomes. [ABSTRACT FROM AUTHOR]

Objective: The COVID-19 pandemic exacerbated gender disparities in some academic disciplines. This study examined the association of the pandemic with gender authorship disparities in clinical neuropsychology (CN) journals. Method: Author bylines of 1,018 initial manuscript submissions to four major CN journals from March 15 through September 15 of both 2019 and 2020 were coded for binary gender. Additionally, authorship of 40 articles published on pandemic-related topics (COVID-19, teleneuropsychology) across nine CN journals were coded for binary gender. Results: Initial submissions to these four CN journals increased during the pandemic (+27.2%), with comparable increases in total number of authors coded as either women (+23.0%) or men (+25.4%). Neither the average percentage of women on manuscript bylines nor the proportion of women who were lead and/or corresponding authors differed significantly across time. Moreover, the representation of women as authors of pandemic-related articles did not differ from expected frequencies in the field. Conclusions: Findings suggest that representation of women as authors of peer-reviewed manuscript submissions to some CN journals did not change during the initial months of the COVID-19 pandemic. Future studies might examine how risk and protective factors may have influenced individual differences in scientific productivity during the pandemic. [ABSTRACT FROM AUTHOR]

This study investigated the best estimate of true Wechsler Adult Intelligence Scale-Revised (WAIS-R) Full Scale IQ for people who recently had been administered the WAIS-R using 65 college students. Results indicate the Verbal IQ, Verbal Comprehension factor score, and subtracting six points from the current full scale IQ yield the best estimates. (SLD)

Objective: The addition of Sequencing to WAIS-IV Digit Span (DS) brought about new Reliable Digit Span (RDS) indices and an Age-Corrected Scaled Score that includes Sequencing trials. Reports have indicated that these new performance validity tests (PVTs) are superior to the traditional RDS; however, comparisons in the context of known neurocognitive impairment are sparse. This study compared DS-derived PVT classification accuracies in a design that included adults with verified TBI. Methods: Participants included 64 adults with moderate-to-severe TBI (TBI), 51 healthy adults coached to simulate TBI (SIM), and 78 healthy comparisons (HC). Participants completed the WAIS-IV DS subtest in the context of a larger test battery. Results: Kruskal–Wallis tests indicated that all DS indices differed significantly across groups. Post hoc contrasts revealed that only RDS Forward and the traditional RDS differed significantly between SIM and TBI. ROC analyses indicated that RDS variables were comparable predictors of SIM vs. HC; however, the traditional RDS showed the highest sensitivity when approximating 90% specificity for SIM vs. TBI. A greater percentage of TBI scored RDS Sequencing < 1 compared to SIM and HC. Conclusion: In the context of moderate-to-severe TBI, the DS-derived PVTs showed comparable discriminability. However, the Greiffenstein et al. traditional RDS demonstrated the best classification accuracy with respect to specificity/sensitivity balance. This relative superiority may reflect that individuals with verified TBI are more likely to perseverate on prior instructions during DS Sequencing. Findings highlight the importance of including individuals with verified TBI when evaluating and developing PVTs. [ABSTRACT FROM AUTHOR]

Background and Purpose: Driving a motor vehicle is an essential activity of daily living for adults; however, few studies have examined the effects of driving cessation on community integration among stroke survivors. The present study investigated this relationship as well as social support and gender as potential moderators of outcome. Method: Ninety pairs of stroke survivors and informants participated. Objective community integration (mobility, occupation, social integration) was assessed via informant ratings, whereas subjective community integration and social support were assessed via selfreport. These poststroke outcomes were compared for survivors who did and did not resume driving post stroke. Results: Multivariate analysis of covariance (MANCOVA) indicated that drivers were more mobile and made more productive use of their time than did non-drivers, even after accounting for stroke severity and use of alternative transportation. Two interaction effects were observed: Drivers with high social support showed better community integration than did nondrivers and drivers with low social support. Additionally, among men, non-drivers fared substantially worse than drivers, whereas among women, drivers and non-drivers showed equivalent community integration. Conclusion: Driving status has unique and substantial influence on community integration following stroke. Social support facilitated community integration but did not substantially buffer the effects of driving cessation. Although men and women resumed driving at equal rates, driving cessation showed differential effects for men and women in regard to their community integration. Research is needed to design interventions that promote full engagement in community living among persons who cease driving after stroke. Key words: community integration, driving, gender differences, social support, stroke, Driving a motor vehicle is essential to functional independence and community integration, as it enables access to work, shopping, health care, and social activities, (1-5) Most adults are understandably resistant [...]

Internal consistency reliabilities were computed for the Tactual Performance Test Memory and Location scores (N = 602). After adjusting for unequal item difficulty, the reliabilities for Memory and Location were .69 and .79, respectively.

The present study tested the incremental utility of response time (RT) on the Warrington Recognition Memory Test – Words (RMT-W) in classifying bona fide versus feigned TBI. Participants were 173 adults: 55 with moderate to severe TBI, 69 healthy comparisons (HC) instructed to perform their best, and 49 healthy adults coached to simulate TBI (SIM). Participants completed a computerized version of the RMT-W in the context of a comprehensive neuropsychological battery. Groups were compared on RT indices including mean RT (overall, correct trials, incorrect trials) and variability, as well as the traditional RMT-W accuracy score. Several RT indices differed significantly across groups, although RMT-W accuracy predicted group membership more strongly than any individual RT index. SIM showed longer average RT than both TBI and HC. RT variability and RT for incorrect trials distinguished SIM-HC but not SIM-TBI comparisons. In general, results for SIM-TBI comparisons were weaker than SIM-HC results. For SIM-HC comparisons, classification accuracy was excellent for all multivariable models incorporating RMT-W accuracy with one of the RT indices. For SIM-TBI comparisons, classification accuracies for multivariable models ranged from acceptable to excellent discriminability. In addition to mean RT and RT on correct trials, the ratio of RT on correct items to incorrect items showed incremental predictive value to accuracy. Findings support the growing body of research supporting the value of combining RT with PVTs in discriminating between verified and feigned TBI. The diagnostic accuracy of the RMT-W can be improved by incorporating RT. [ABSTRACT FROM AUTHOR]

Describe who is able to return to driving (RTD) after moderate-to-severe traumatic brain injury (TBI), when this occurs, who maintains that activity, and the association with outcome. Cross-sectional descriptive study. Eight follow-up sites of the TBI Model Systems (TBIMS) program. 618 participants enrolled in the TBIMS and 88 caregivers (N=706). Not applicable. A survey was completed from 1-30 years postinjury focusing on RTD. Descriptors included demographic information, injury severity, and current employment status. Outcome was assessed at the time of the interview, including depression, quality of life, functional status, and community participation. Of 706 respondents, 78% (N = 552) RTD, but 14% (N = 77) of these did not maintain that activity. Of those who RTD, 43% (N = 192) did so within 6 months of the injury and 92% did so within 24 months postinjury. The percentage of people driving after TBI did not differ significantly based on age at time of injury or follow-up. There were significant differences between drivers and nondrivers with respect to severity of injury, seizures, race, education, employment, rural vs urban setting, marital status, and family income. We performed a multivariate logistic regression to examine the association between driving status and demographic variables, adjusting for other variables in the model. The strongest associations were with current employment, family income, race, seizures, and severity of injury. Driving was associated with greater community participation, better functional outcomes, fewer symptoms of depression, and greater life satisfaction. Over a span of 30 years, three-quarters of people experiencing moderate-to-severe TBI return to driving a personal vehicle, although not everyone maintains this activity. Employment, race, family income, and seizures are strongly associated with RTD. [ABSTRACT FROM AUTHOR]

Describe driving patterns following moderate-to-severe traumatic brain injury (TBI). Participants: Adults (N = 438) with TBI that required inpatient acute rehabilitation who had resumed driving. Cross-sectional, observational design. Eight TBI Model System sites. A driving survey was completed at phone follow-up. Most respondents reported driving daily, although 41% reported driving less than before their injury. Driving patterns were primarily associated with employment, family income, sex, residence, and time since injury, but not injury severity. Confidence in driving was high for most participants and was associated with a perception that the TBI had not diminished driving ability. Lower confidence and perceived loss of ability were associated with altered driving patterns. Most people with moderate-to-severe TBI resume driving but perhaps not at pre-injury or normal levels compared to healthy drivers. Some driving situations are restricted. The relationship between low confidence/perceived loss of ability and driving patterns/restrictions suggests people with TBI are exhibiting some degree of caution consistent with those perceptions. Careful assessment of driving skills and monitoring during early stages of RTD is warranted, particularly for younger, male, and/or single drivers who express higher levels of confidence. [ABSTRACT FROM AUTHOR]

Purpose: The purpose was to examine the role of therapy engagement as a potential mediator for the relationship between neuropsychological performance and functional outcomes. Materials and method: Participants were 94 adults with medically documented ABI recruited from three outpatient rehabilitation clinics at the start of occupational therapy. Participants (57% men) ranged from 18 to 82 in age, with the majority (81%) having completed 12 or more years of education. They completed a comprehensive neuropsychological assessment at baseline. Separately, occupational therapists (OTs) assessed functional independence and disability at baseline and follow up. The OTs also rated the participants' therapy engagement. Results: Therapy engagement predicted functional outcomes and mediated the relationship between neuropsychological performance and outcomes. Moreover, therapy engagement accounted for unique variance in functional outcome, even after accounting for education, comorbid health conditions, emotional distress, apathy, and baseline functional ability. Conclusions: Engagement in therapy is a crucial patient characteristic in successful rehabilitation outcome. Cognitive deficits associated with ABI undermine full engagement in rehabilitation therapy, which in turn diminishes potential gains made in therapy and functional recovery. Neuropsychological assessment can enhance rehabilitation outcomes by identifying characteristics that underlie therapy engagement, which can ultimately be used to maximize the effectiveness of individualized treatment plans. Neuropsychological assessment can identify cognitive abilities that are strongly related to functional outcomes during occupational therapy for acquired brain injury. Therapy engagement is an important pathway by which neuropsychological impairment predicts functional outcomes after acquired brain injuries. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to examine pain anxiety after acquired brain injury (ABI) and its relationship to rehabilitation outcomes. Materials and Method: Participants consisted of 89 adults with an ABI participating in outpatient rehabilitation therapy. They completed a battery of neuropsychological tests at baseline along with surveys of mood, health-related self-efficacy, and pain anxiety. Separately, occupational therapists assessed basic and instrumental activities of daily living (ADLs) as well as therapy engagement across treatment after the sixth session. Results: Individuals who reported high pain anxiety had fewer years of formal education, lower self-efficacy, and more emotional distress than those with low pain anxiety. Although Blacks were about half (56%) of the study sample, they comprised the majority (73.1%) of individuals in the high pain anxiety group. Pain anxiety was negatively related to therapy engagement. Moderation analysis using linear regression indicated that pain anxiety moderated the influence of self-efficacy on basic ADLs. Conclusions: Pain anxiety, particularly when high, is negatively associated with rehabilitation outcomes for individuals with ABI. Among those with high pain anxiety, health-related self-efficacy is an important resilience characteristic to improve functional outcomes. In rehabilitation therapy, pain anxiety provides a novel intervention target to enhance ABI recovery. [ABSTRACT FROM AUTHOR]

Purpose: This study examined the extent to which resilience is associated with well-being outcomes after traumatic brain injury, and whether those relationships are independent of global personality traits, such as affectivity. Materials and methods: Sixty-seven adults with complicated-mild to severe traumatic brain injury participated. Measures included the Connor-Davidson Resilience Scale, Modified Cumulative Illness Rating Scale, Disability Rating Scale, SF-12 Health Survey, Satisfaction with Life Scale, and Community Integration Measure. Results: Objective physical health and disability showed modest relation to resilience, indicating that adverse health conditions and disability decreased with increasing resilience. The three measures of subjective well-being showed modest-to-strong positive relation to resilience. These correlations between resilience and well-being generally remained significant after accounting for negative and positive affectivity. Results also suggest that the influence of resilience on well-being has a threshold effect: a greater influence on outcome among people with low or inadequate resilience than among people with average or high resilience. Conclusion: The experience of brain injury does not diminish the positive influence resilience may have on long-term well-being. Resilience may function as a buffer to trauma even in the challenging context of cognitive insult. Routine assessment of resilience might be beneficial to the rehabilitation team. Resilience is positively associated with subjective and objective well-being among adults with moderate-to-severe traumatic brain injury, and it appears to function among adults with traumatic brain injury similarly to adults without cognitive disabilities. Resilience overlaps with overarching trait personality constructs such as affectivity; yet, it has unique characteristics and unique value in understanding well-being. The adverse effects of low resilience show stronger influence on well-being than do the positive effects of high resilience. Routine assessment of resilience might be beneficial to the rehabilitation team in understanding patients and their families, especially in discharge planning, where beliefs about personal capabilities to rebound from adversity shape likely future behavior. [ABSTRACT FROM AUTHOR]

Purpose: Early detection of hearing loss is important for providing support and intervention for adults with age-related hearing loss. However, many older adults have hearing loss that is unidentified. Because they do not present the problem at health care settings, there is a dearth of research on people with unrecognized hearing loss (URHL). This study elucidates differences between older adults with normal hearing, adults with recognized hearing loss (RHL), and adults with URHL. Method: Participants included 130 adults, ages 55--85 years. Of these, 39 had hearing in the normal range (HNR), 61 had RHL, and 30 reported HNR but failed a hearing screen (i.e., URHL). Participants completed the Positive and Negative Affect Schedule (PANAS; Watson, Clark, & Tellegen, 1988) and a battery of neuropsychological tests. Results: The URHL group reported more positive affectivity than the HNR and RHL groups on the PANAS. In addition, the URHL group was significantly older and more likely to be male compared to the HNR group. Importantly, age was not significantly correlated with PANAS. Positive affectivity accounted for unique variance in group membership even after accounting for age, gender, physical health, and cognitive health. Conclusions: Older adults with URHL have more positive affectivity than older adults with HNR or RHL. This group may be prone to downplaying their difficulties; consequently, they may need to experience larger hearing deficits before seeking help. The findings highlight the need for research investigating the effectiveness of psychoeducation on the importance of formal hearing assessment verses relying on self-assessment in facilitating early and effective intervention among people with URHL. [ABSTRACT FROM AUTHOR]

This study examined the hypothesis that people who receive concussion recovery education would have better outcomes than those who received usual discharge paperwork from the emergency department (ED) and tested whether participants who were in litigation or seeking disability compensation had more symptoms than individuals not engaged in these activities. Two hundred and fifty-five persons with a diagnosis of concussion were assigned randomly to a brief education group (one-page double-sided document), a longer education group (10-page document), and usual care (standard ED discharge instructions), and were these documents in the ED. A (non-concussion) trauma comparison group was enrolled to determine the symptom rate unrelated to brain injury. The Concussion Symptom Checklist (CSC) and litigation and disability status questions were completed by telephone at one week, three months, and six months. Neither long nor brief information handouts had a significant impact on symptoms over time; the standard form had an average decrease of 1.20 symptoms compared with the brief instructional intervention group (p = 0.031). Litigation status and disability seeking status were significant predictors of symptoms on CSC over time: disability seeking (p = 0.017) and litigation status (p = 0.05). Persons seeking Social Security disability or legal compensation endorsed more symptoms over time than those who were not. Number of symptoms on the CSC for the trauma control group was the same as those who sustained concussion. Type of recovery material was not as important as noting that concussion symptoms resolve over time, and that remaining symptoms are not specific to brain injury. Litigation and disability seeking behavior accounted for maintained symptoms, rather than the concussion itself. [ABSTRACT FROM AUTHOR]

Objective: The present study examined the incremental utility of item-level response time (RT) variables on a traditional performance validity test in distinguishing adults with verified TBI from adults coached to feign neurocognitive impairment. Method: Participants were 45 adults with moderate to severe TBI, 45 healthy adults coached to feign neurocognitive impairment (SIM), and 61 healthy adult comparisons providing full effort (HC). All participants completed a computerized version of the Test of Memory Malingering (TOMM-C) in the context of a larger test battery. RT variables examined along with TOMM-C accuracy scores included mean RTs (Trial 1, Trial 2, correct and incorrect trials) and RT variability indices. Results: Several RT indices differed significantly across the groups. In general, SIM produced longer, more variable RTs than HC and TBI. Of the RT indices, average RT for Trial 1 and 2 were the best predictors of group membership; however, classification accuracies were greatly influenced by the groups being compared. Average RT for Trial 1 and 2 showed excellent discrimination of SIM and HC. All RT indices were less successful in discriminating SIM and TBI. Average RT for Trial 1 and 2 added incremental predictive value to TOMM-C accuracy in distinguishing SIM from TBI. Conclusion: Findings contribute to a limited body of research examining the incremental utility of combining RT with traditional PVTs in distinguishing feigned and bona fide TBI. Findings support the hypothesis that combining RT with TOMM-C accuracy can improve its diagnostic accuracy. Future research with other groups of clinical interest is recommended. [ABSTRACT FROM AUTHOR]