Intraindividual Variability in Attention-Deficit/Hyperactivity Disorder: An Ex-Gaussian Approach.

Higher intraindividual variability (IIV) of response times is consistently noted in children with attention-deficit/hyperactivity disorder (ADHD). The current study investigated whether an ex-Gaussian estimate of IIV in children ages 6-13 years-old could differentiate between children with and without ADHD. Children completed a computerized go/no-go task to estimate trial-by-trial IIV and a continuous performance test (CPT) to estimate inattention and hyperactivity/impulsivity. Parents completed questionnaires assessing inattention and hyperactive/impulsive behaviors. IIV, commission errors, and attention problems as rated by parents were significantly greater in the ADHD group. Groups did not differ on errors of omission, but IIV was predictive of omission errors and parent ratings of inattention and hyperactivity/impulsivity. IIV predicted group membership (ADHD vs Control) whereas errors of omission did not. However, IIV did not improve diagnostic accuracy when parent ratings were used, such that parent ratings were superior at determining diagnosis. Current results support the use of IIV, based on the ex-Gaussian approach, as an objective measure of attention problems over omission errors on sustained attention CPT-type tasks. Additionally, while parent ratings of attention impairment remain the best predictor of ADHD diagnostic status, IIV may be helpful in determining when further assessment is required in the absence of those ratings.

Cognitive, Sleep-Arousal, Physical, and Affective Domain Scores on the Post-Concussion Symptom Scale: Added Utility in Detecting Symptom Elevations among Student-Athletes with a Remote History of Concussion.

OBJECTIVE: The evaluation of self-reported symptoms is a standard component of concussion assessment and management. Clinicians typically evaluate a total symptom severity score rather than scores corresponding to specific symptom domains (i.e., cognitive, sleep-arousal, physical, and affective symptoms). This study examined (i) whether elevations in specific symptom domains would be missed when interpreting only the total symptom severity score and (ii) if a single symptom domain elevation was more common than having elevated symptoms across multiple domains. METHOD: Adolescent student-athletes (N = 1,008) with concussion history (i.e., ≥6 months since last concussion) completed the Post-Concussion Symptom Scale (PCSS). The PCSS total score and cognitive, sleep-arousal, physical, and affective domain scores were calculated. To determine if symptoms were elevated, scores were compared to normative data matched on gender and pre-existing conditions, with scores considered elevated if they were ≥84th percentile. The frequency of total and domain score elevations were calculated and stratified by gender and number of prior concussions (i.e., 1 or ≥2 prior concussions). RESULTS: Overall, 26% of student-athletes had an elevated symptom domain score without being elevated on the total score. The most common symptom presentation was to have a single elevated symptom domain (21%), followed by two (11%), three (8%), or four elevated domains (6%). CONCLUSIONS: Interpreting PCSS symptom domains may be beneficial in detecting student-athletes with elevated symptoms following a remote concussion. Roughly a quarter of student-athletes have domain-specific symptom elevations that would be missed by interpreting the total score alone.

The Neurobehavioral Symptom Inventory: Psychometric Properties and Symptom Comparisons in Women With and Without Brain Injuries Due to Intimate Partner Violence.

This study psychometrically evaluated the Neurobehavioral Symptom Inventory (NSI) among women survivors of intimate partner violence (IPV) and compared symptoms between women with no brain injury history (n = 93) and women with IPV-related brain injury history (n = 112). Women completed the NSI and questionnaires on traumatic brain injury (TBI), hypoxic-ischemic brain injury (HI-BI), and lifetime IPV history. A four-factor NSI model, including affective, somatosensory, cognitive, and vestibular factors, had the best fit (comparative fit index = 0.970, root mean square error of approximation = 0.064), with strong reliability for the total score (ω = .93) and subscale scores (ω range = .72-.89). In group comparisons, women with IPV-related brain injuries reported greater total, affective, and cognitive symptom severity after adjusting for age and education; however, no group differences were observed after adjusting for IPV severity. When examining lifetime number of brain injuries, HI-BI count was independently predictive of total, cognitive, and vestibular symptom severity after adjusting for age, education, and IPV severity; whereas TBI count did not independently predict any NSI scores after adjusting for these covariates. The NSI had acceptable psychometric properties for measuring neurobehavioral symptoms among women survivors of IPV. The association between HI-BI count and cognitive and vestibular symptoms may indicate the importance of studying repetitive nonfatal strangulation as an injury mechanism in this population.

Treatment of chronic symptoms following mild traumatic brain injury with transcranial LED: a sham run-in pilot study of photobiomodulation therapy.

PRIMARY OBJECTIVE: We evaluated whether photobiomodulation with red/near infrared light applied transcranially via light emitting diodes (LED) was associated with reduced symptoms and improved cognitive functioning in patients with chronic symptoms following mild traumatic brain injury. RESEARCH DESIGN: Participants (3 men, 6 women; 22-61 years-old) underwent a 6-week intervention involving 18 40-minute transcranial LED treatment sessions. METHODS AND PROCEDURES: Reliable change indices were calculated for 10 neuropsychological test scores and 3 self-report questionnaires of subjective cognition, post-concussion symptoms, and depression at baseline and following treatment. Questionnaires were also administered after 2-week sham and at 1-month and 2-month follow-ups. MAIN OUTCOME AND RESULTS: Only 2 participants improved on neuropsychological testing. On questionnaires, 4 reported improved cognition, 5 reported improved post-concussion symptoms, and 3 reported improved depression. Significant improvement in 2 or more domains was reported by 4 participants and mostly maintained at both follow-ups. CONCLUSIONS: Most participants did not improve on neuropsychological testing. A minority self-reported improvement in symptoms, potentially explained by the intervention, psychiatric medication changes, placebo effects, or other factors. Selecting participants with different clinical characteristics, and dosing and delivery system changes, may produce different results. A study design accounting for placebo effects appears warranted in future trials.

The Sport Concussion Assessment Tool: A multidimensional symptom model for detecting elevated post-concussion symptoms.

Objective: Investigate whether a four-factor model of post-concussion symptoms (i.e. cognitive, physical, affective, and sleep-arousal) aids in identifying student-athletes with persistent concerns not reflected by a total symptom score. Method: Collegiate student-athletes (N = 32,066) from the Concussion Assessment Research and Education consortium completed the Sport Concussion Assessment Tool, 3rd edition Symptom Evaluation at baseline and two post-injury follow-ups (i.e. beginning RTP and 6-month). Confirmatory factor analysis was used to compare a one- and four-factor model of post-concussion symptoms. Normative reference data were compared across stratifications (e.g. sex, prior concussions, and number of pre-existing conditions) using Mann-Whitney U tests, and elevation rates (i.e. ≥84th percentile) for subscales and the total score were recorded. Results: The four-factor model fit well before and after injury (CFIs > .95). Greater symptom severity on the subscale and total scores was associated with female sex (ps<.001, r range: .07 to .14) and more pre-existing conditions (ps<.001, η2 range: .01 to .04), while having more prior concussions was only related to total symptom scores (ps<.001, η2<.01). After a concussion, a sizeable portion of student-athletes (i.e., RTP = 11.8%; 6-month = 8.3%) had subscale elevations despite no total score elevation. Physical subscale elevations at RTP were the most common (i.e., 11.9%), driven by head and neck pain. Conclusion: After a sport-related concussion, a four-factor symptom model can be used to assess persistent symptoms in collegiate student-athletes. Identifying athletes with domain-specific elevations may help clinicians identify areas for further assessment and, in some cases, personalized rehabilitation plans.

Test-Retest Reliability and Reliable Change on the NIH Toolbox Cognition Battery.

OBJECTIVE: Researchers and practitioners can detect cognitive improvement or decline within a single examinee by applying a reliable change methodology. This study examined reliable change through test-retest data from the English-language National Institutes of Health Toolbox Cognition Battery (NIHTB-CB) normative sample. METHOD: Participants included adults (n = 138; age: M ± SD = 54.8 ± 20.0, range: 18-85; 51.4% men; 68.1% White) who completed test-retest assessments about a week apart on five fluid cognition tests, providing raw scores, age-adjusted standard scores (SS), and demographic-adjusted T-scores (T). RESULTS: The Fluid Cognition Composite (SS: ICC = 0.87; T-score: ICC = 0.84) and the five fluid cognition tests had good test-retest reliability (SS: ICC range = 0.66-0.85; T-score: ICC range = 0.64-0.86). The lower and upper bounds of 70%, 80%, and 90% confidence intervals (CIs) were calculated around change scores, which serve as cutoffs for determining reliable change. Using T-scores, 90% CI, and adjustment for practice effects, 32.3% declined on one or more tests, 9.7% declined on two or more tests, 36.6% improved on one or more tests, and 5.4% improved on two or more tests. CONCLUSIONS: It was common for participants to show reliable change on at least one test score, but not two or more test scores. Per an 80% CI, test-retest difference scores beyond these cutoffs would indicate reliable change: Dimensional Change Card Sort (SS ≥ 14/T ≥ 10), Flanker (SS ≥ 12/T ≥ 8), List Sorting (SS ≥ 14/T ≥ 10), Picture Sequence Memory (SS ≥ 19/T ≥ 13), Pattern Comparison (SS ≥ 11/T ≥ 8), and Fluid Cognition Composite (SS ≥ 10/T ≥ 7). The reliable change cutoffs could be applied in research or practice to detect within-person change in fluid cognition at the individual level.

Preliminary Evaluation of the Scandinavian Guidelines for Initial Management of Minimal, Mild, and Moderate Head Injuries with Glial Fibrillary Acidic Protein.

Glial fibrillary acidic protein (GFAP) has become the most promising biomarker for detecting traumatic abnormalities on head computed tomography (CT) in patients with traumatic brain injury (TBI), but most studies have not addressed the potential added value of combining the biomarker with clinical variables that confer risk for intracranial injuries. The Scandinavian Guidelines for Initial Management of Minimal, Mild, and Moderate Head Injuries in Adults were the first clinical decision rules in the field with an incorporated biomarker, the S100 astroglial calcium-binding protein B (S100B), which is used in the Mild (Low Risk) group defined by the guidelines. Our aim was to evaluate the performance of the guidelines when S100B was substituted with GFAP. The sample (N = 296) was recruited from the Tampere University Hospital's emergency department between November 2015 and November 2016, and there were 49 patients with available GFAP results who were stratified in the Mild (Low Risk) group (thus patients undergoing biomarker triaging). A previously reported cutoff of plasma GFAP ≥140 pg/mL was used. Within the Mild (Low Risk) group (n = 49), GFAP sensitivity (with 95% confidence intervals in parentheses) for detecting traumatic CT abnormalities was 1.0 (0.40-1.00), specificity 0.34 (0.19-0.53), the negative predictive value (NPV) 1.0 (0.68-1.00), and the positive predictive value (PPV) 0.16 (0.05-0.37). The sensitivity and specificity of the modified guidelines with GFAP, when applied to all imaged patients (n = 197) in the whole sample, were 0.94 (0.77-0.99) and 0.20 (0.15-0.28), respectively. NPV was 0.94 (0.80-0.99) and PPV 0.18 (0.13-0.25). In the Mild (Low Risk) group, none of the patients with GFAP results below 140 pg/mL had traumatic abnormalities on their head CT. These findings were derived from a small patient subgroup. Future researchers should replicate these findings in larger samples and assess whether GFAP has added or comparable value to S100B in acute TBI management.

The Short Executive Function Scale.

This study involved a psychometric evaluation of the Short Executive Function Scale (SEFS), a new 15-item self-report questionnaire measuring five constructs: Planning, Inhibition, Working Memory, Shifting, and Emotional Control. Participants included 717 U.S. undergraduate students (M = 18.9 years old, SD = 1.9; 78.8% cisgender female, 81.7% White) who completed the SEFS. A subset of 156 participants (M = 18.8 years old, SD = 0.9; 79.5% cisgender female, 83.3% White) completed the SEFS again at 2- to 3-month retest along with the Behavior Rating Inventory of Executive Function-Adult (BRIEF-A) and the Patient Health Questionnaire (PHQ-8). The five-factor model fit well (CFI = 0.941, RMSEA = 0.079) and each scale had acceptable internal consistency (ω range: .68-.81) and test-retest reliability (ICC range: .75-.89). Apart from Shifting, all SEFS scales had significantly larger convergent validity coefficients with their respective BRIEF-A scales (r range: -.25 to -.70) than discriminant validity coefficients with the PHQ-8 (r range: -.06 to -.28). These findings provide preliminary psychometric support for the SEFS.

Multivariate base rates of potentially problematic scores on the NIH Toolbox Emotion Battery.

OBJECTIVE: To examine the normal frequency of obtaining one or more scores considered potentially problematic based on normative comparisons when completing the NIH Toolbox Emotion Battery (NIHTB-EB). METHOD: Participants (N = 753; ages 18-85, 62.4% women, 66.4% non-Hispanic White) from the NIHTB norming study completed 17 scales of emotional functioning fitting into three subdomains (i.e., Negative Affect, Psychological Well-being, Social Satisfaction). Scores were considered potentially problematic if they were 1 SD above/below the mean, depending on the orientation of the scale, and cutoffs for 1.5 and 2 SD were also included for reference. Multivariate base rates quantified the rate at which participants obtained one or more potentially problematic scale or subdomain scores. RESULTS: The portion of participants obtaining one or more potentially problematic scores on the NIHTB-EB scales and subdomains was 61.2 and 23.2%, respectively. Participants who were younger (i.e., 18-49) or had less education had higher rates of potentially problematic scores within specific subdomains. There were no significant differences by sex or race/ethnicity. CONCLUSIONS: Elevated scores on the NIHTB-EB were common in the normative sample and related to education/age. The multivariate base rates provided indicate obtaining one or more potentially problematic scores on the NIHTB-EB is broadly normal among adults, which may guard against overinterpreting a single score as clinically significant. These base rates should be considered in the context of other assessment findings, such as interviews, medical history or informant reports, to ensure that true emotional problems are not dismissed, and normal variation in emotional functioning is not pathologized.

Post-Traumatic Headache is Associated with Worse Anxiety and Mood Symptoms in Adolescent Mild Traumatic Brain Injury.

This study examined the relationships between post-traumatic headache (PTH) and mental health symptoms after concussions to inform adolescent concussion management. Headache is the most common complaint following adolescent concussion. In this sample of 123 adolescents with concussion, there was a 5-fold increase in odds of clinically elevated anxiety, as well as increased mental health symptoms (anxiety, depression, anger, and disruptive behaviours), among adolescents with PTH relative to those without PTH. Adolescents with headache following concussions are vulnerable to worse mental health outcomes, particularly anxiety, and may benefit from routine monitoring of mental health symptoms for early detection and intervention.