Questionnaire and structural imaging data accurately predict headache improvement in patients with acute post-traumatic headache attributed to mild traumatic brain injury.

BACKGROUND: Our prior work demonstrated that questionnaires assessing psychosocial symptoms have utility for predicting improvement in patients with acute post-traumatic headache following mild traumatic brain injury. In this cohort study, we aimed to determine whether prediction accuracy can be refined by adding structural magnetic resonance imaging (MRI) brain measures to the model. METHODS: Adults with acute post-traumatic headache (enrolled 0-59 days post-mild traumatic brain injury) underwent T1-weighted brain MRI and completed three questionnaires (Sports Concussion Assessment Tool, Pain Catastrophizing Scale, and the Trait Anxiety Inventory Scale). Individuals with post-traumatic headache completed an electronic headache diary allowing for determination of headache improvement at three- and at six-month follow-up. Questionnaire and MRI measures were used to train prediction models of headache improvement and headache trajectory. RESULTS: Forty-three patients with post-traumatic headache (mean age = 43.0, SD = 12.4; 27 females/16 males) and 61 healthy controls were enrolled (mean age = 39.1, SD = 12.8; 39 females/22 males). The best model achieved cross-validation Area Under the Curve of 0.801 and 0.805 for predicting headache improvement at three and at six months. The top contributing MRI features for the prediction included curvature and thickness of superior, middle, and inferior temporal, fusiform, inferior parietal, and lateral occipital regions. Patients with post-traumatic headache who did not improve by three months had less thickness and higher curvature measures and notably greater baseline differences in brain structure vs. healthy controls (thickness: p < 0.001, curvature: p = 0.012) than those who had headache improvement. CONCLUSIONS: A model including clinical questionnaire data and measures of brain structure accurately predicted headache improvement in patients with post-traumatic headache and achieved improvement compared to a model developed using questionnaire data alone.

T2* reduction in patients with acute post-traumatic headache.

OBJECTIVES: Although iron accumulation in pain-processing brain regions has been associated with repeated migraine attacks, brain structural changes associated with post-traumatic headache have yet to be elucidated. To determine whether iron accumulation is associated with acute post-traumatic headache, magnetic resonance transverse relaxation rates (T2*) associated with iron accumulation were investigated between individuals with acute post-traumatic headache attributed to mild traumatic brain injury and healthy controls. METHODS: Twenty individuals with acute post-traumatic headache and 20 age-matched healthy controls underwent 3T brain magnetic resonance imaging including quantitative T2* maps. T2* differences between individuals with post-traumatic headache versus healthy controls were compared using age-matched paired t-tests. Associations of T2* values with headache frequency and number of mild traumatic brain injuries were investigated using multiple linear regression in individuals with post-traumatic headache. Significance was determined using uncorrected p-value and cluster size threshold. RESULTS: Individuals with post-traumatic headache had lower T2* values compared to healthy controls in cortical (bilateral frontal, bilateral anterior and posterior cingulate, right postcentral, bilateral temporal, right supramarginal, right rolandic, left insula, left occipital, right parahippocampal), subcortical (left putamen, bilateral hippocampal) and brainstem regions (pons). Within post-traumatic headache subjects, multiple linear regression showed a negative association between T2* in the right inferior parietal/supramarginal regions and number of mild traumatic brain injuries and a negative association between T2* in bilateral cingulate, bilateral precuneus, bilateral supplementary motor areas, bilateral insula, right middle temporal and right lingual areas and headache frequency. CONCLUSIONS: Acute post-traumatic headache is associated with iron accumulation in multiple brain regions. Correlations with headache frequency and number of lifetime mild traumatic brain injuries suggest that iron accumulation is part of the pathophysiology or a marker of mild traumatic brain injury and post-traumatic headache.

The Aphasia Communication Outcome Measure (ACOM): Dimensionality, Item Bank Calibration, and Initial Validation.

PURPOSE: The purpose of this study is to investigate the structure and measurement properties of the Aphasia Communication Outcome Measure (ACOM), a patient-reported outcome measure of communicative functioning for persons with aphasia. METHOD: Three hundred twenty-nine participants with aphasia responded to 177 items asking about communicative functioning. The data were analyzed using a categorical item factor analysis approach. Validity of ACOM scores on the basis of their convergence with performance-based, clinician-reported, and surrogate-reported assessments of communication was also assessed. RESULTS: Fifty-nine items that obtained adequate fit to a modified bifactor measurement model and functioned similarly across several demographic and clinical subgroupings were identified. The factor model estimates were transformed to item response theory graded response model parameters, and the resulting score estimates showed good precision and moderately strong convergence with other measures of communicative ability and functioning. A free software application for administration and scoring of the ACOM item bank is available from the first author. CONCLUSIONS: The ACOM provides reliable measurement of patient-reported communicative functioning in aphasia. The results supported the validity of ACOM scores insofar as (a) factor analyses provided support for a coherent measurement model, (b) items functioned similarly across demographic and clinical subgroups, and (c) scores showed good convergence with measures of related constructs.

Self- and surrogate-reported communication functioning in aphasia.

PURPOSE: To evaluate the dimensionality and measurement invariance of the aphasia communication outcome measure (ACOM), a self- and surrogate-reported measure of communicative functioning in aphasia. METHODS: Responses to a large pool of items describing communication activities were collected from 133 community-dwelling persons with aphasia of ≥ 1 month post-onset and their associated surrogate respondents. These responses were evaluated using confirmatory and exploratory factor analysis. Chi-square difference tests of nested factor models were used to evaluate patient-surrogate measurement invariance and the equality of factor score means and variances. Association and agreement between self- and surrogate reports were examined using correlation and scatterplots of pairwise patient-surrogate differences. RESULTS: Three single-factor scales (Talking, Comprehension, and Writing) approximating patient-surrogate measurement invariance were identified. The variance of patient-reported scores on the Talking and Writing scales was higher than surrogate-reported variances on these scales. Correlations between self- and surrogate reports were moderate-to-strong, but there were significant disagreements in a substantial number of individual cases. CONCLUSIONS: Despite minimal bias and relatively strong association, surrogate reports of communicative functioning in aphasia are not reliable substitutes for self-reports by persons with aphasia. Furthermore, although measurement invariance is necessary for direct comparison of self- and surrogate reports, the costs of obtaining invariance in terms of scale reliability and content validity may be substantial. Development of non-invariant self- and surrogate report scales may be preferable for some applications.

The Burden of Stroke Scale (BOSS) provided valid, reliable, and responsive score estimates of functioning and well-being during the first year of recovery from stroke.

OBJECTIVES: To examine the reliability, validity, and responsiveness of the Burden of Stroke Scale (BOSS). STUDY DESIGN: A prospective cohort of stroke survivors were assessed at 3 (T1, T2), 6 (T3), and 12 (T4) months post onset (MPO) of stroke. Test-retest reliability was evaluated by calculating intra-class correlation coefficients (ICCs) between T1 and T2 scale scores. Convergent validity was evaluated by calculating Pearson product moment correlation coefficients between T1 BOSS, Stroke Impact Scale and MOS SF-36 scale scores assessing similar health concepts. Responsiveness was evaluated using a repeated measures ANOVA and the linear trend test in the full study sample and by calculating standardized response means (SRM) and a probability of change statistic, p between T1, T3, and T4 scale scores in participants demonstrating change on external criteria. RESULTS: ICCs ranged from 0.78 to 0.94. Pearson coefficients ranged from -0.57 to -0.86. Moderate to high responsiveness estimates were obtained for 9 of 12 subscales with SRM (p) values ranging from .497 (.690) to 1.161 (.877). Composite scale SRM (p) values ranged from .661 (.746) to 1.192 (.883). CONCLUSIONS: The BOSS provided valid and reliable score estimates that were responsive to positive changes in functioning and well-being during the first year of recovery from stroke.

Discriminative validity of selected measures for differentiating normal from aphasic performance.

Normal elderly and mildly aphasic individuals may exhibit similar impairments in comprehension and expression. The discriminative validity between normal and aphasic performance on most standardized measures of aphasia has not been reported. The authors compared the performance of 18 aphasic and 18 normal adults to determine the discriminative validity of 2 general language measures--the Porch Index of Communicative Ability (B. E. Porch, 1967) and the Western Aphasia Battery (A. Kertesz, 1982)--and 2 functional communication measures--the Communication Activities of Daily Living-Second Edition (A. L. Holland, C. Frattali, and D. Fromm, 1999) and the American Speech-Language-Hearing Association's Functional Assessment of Communication Skills for Adults (C. Frattali, C. K. Thompson, A. L. Holland, C. B. Wohl, and M. K. Ferketic, 1995). All between-groups comparisons of summary scores for each measure showed significant mean differences. Expressive language ability and efficiency of performance best differentiated between the aphasic and normal groups. However, group performance ranges overlapped by at least 10% on each measure. To enhance the differential diagnosis of aphasia, supplementing formal test results with additional subjective and objective evidence is recommended.