Interpreting Clinical Reaction Time Change and Recovery After Concussion: A Baseline Versus Norm-Based Cutoff Score Comparison.

Context: Preseason testing can be time intensive and cost prohibitive. Therefore, using normative data for postconcussion interpretation in lieu of preseason testing is desirable.

Objective: To establish the recovery trajectory for clinical reaction time (RTclin) and assess the usefulness of changes from baseline (comparison of postconcussion scores with individual baseline scores) and norm-based cutoff scores (comparison of postconcussion scores with a normative mean) for identifying impairments postconcussion.

Clinical Reaction Time After Concussion: Change From Baseline Versus Normative-Based Cutoff Scores.

Context: Pre-season testing is often used to establish baseline scores for post-concussion interpretation. However, pre-season testing can be time-intensive and cost-prohibitive, in which case normative data may be used for post-injury interpretation.

Objective: To compare change from baseline and normative-based cutoff scores in interpreting clinical reaction time (RTclin) following concussion.

Estimated age of first exposure to American football and outcome from concussion.

Objective: To examine the association between estimated age at first exposure (eAFE) to American football and clinical measures throughout recovery following concussion.

Methods: Participants were recruited across 30 colleges and universities as part of the National Collegiate Athletic Association (NCAA)-Department of Defense Concussion Assessment, Research and Education Consortium. There were 294 NCAA American football players (age 19 ± 1 years) evaluated 24-48 hours following concussion with valid baseline data and 327 (age 19 ± 1 years) evaluated at the time they were asymptomatic with valid baseline data.

Bifactor Model of the Sport Concussion Assessment Tool Symptom Checklist: Replication and Invariance Across Time in the CARE Consortium Sample.

Background: Identifying separate dimensions of concussion symptoms may inform a precision medicine approach to treatment. It was previously reported that a bifactor model identified distinct acute postconcussion symptom dimensions.

Purpose: To replicate previous findings of a bifactor structure of concussion symptoms in the Concussion Assessment Research and Education (CARE) Consortium sample, examine measurement invariance from pre- to postinjury, and evaluate whether factors are associated with other clinical and biomarker measures.

Clinical Reaction-Time Performance Factors in Healthy Collegiate Athletes.

Context: In the absence of baseline testing, normative data may be used to interpret postconcussion scores on the clinical reaction-time test (RTclin). However, to provide normative data, we must understand the performance factors associated with baseline testing.

Objective: To explore performance factors associated with baseline RTclin from among candidate variables representing demographics, medical and concussion history, self-reported symptoms, sleep, and sport-related features.

Investigating the Range of Symptom Endorsement at Initiation of a Graduated Return-to-Play Protocol After Concussion and Duration of the Protocol: A Study From the National Collegiate Athletic Association-Department of Defense Concussion, Assessment, Research, and Education (CARE) Consortium.

Background: Organizations recommend that athletes should be asymptomatic or symptom-limited before initiating a graduated return-to-play (GRTP) protocol after sports-related concussion, although asymptomatic or symptom-limited is not well-defined.

Hypotheses: (1) There will be a range (ie, beyond zero as indicator of "symptom-free") in symptom severity endorsement when athletes are deemed ready to initiate a GRTP protocol. (2) Baseline symptom severity scores and demographic/preinjury medical history factors influence symptom severity scores at the commencement of the GRTP protocol.

Exercise Guidelines for Gait Function in Parkinson's Disease: A Systematic Review and Meta-analysis.

Unlabelled: This systematic review and meta-analysis is to provide comprehensive evidence-based exercise recommendations targeting walking function for adults with Parkinson's disease.

Methods: Fixed- or random-effect meta-analyses estimated standardized effect sizes (Hedge's g), comparing treatment effects from exercise with nonexercise and another form of exercise (non-EXE control and EXE control). Cuing and exercise duration were used as moderators for subanalyses.

The Prevalence of Traumatic Brain Injury and On-Campus Service Utilization Among Undergraduate Students.

Objective: (1) To examine the prevalence of college-aged students on campus who had a history of concussion(s) or traumatic brain injury (TBI) and associated symptoms and (2) to evaluate the rate of campus service utilization among students who had a TBI.

Setting: A representative sampling, randomly selected campus-wide e-mail was sent out with a Qualtrics online survey.

Participants: College-aged students (N = 466, n = 429) at a northeastern US university responded and consented to participate in the online survey.

Influences of Mental Illness, Current Psychological State, and Concussion History on Baseline Concussion Assessment Performance.

Background: A student-athlete's mental state, including history of trait anxiety and depression, or current psychological state may affect baseline concussion assessment performance.

Purpose: (1) To determine if mental illness (anxiety, depression, anxiety with depression) influences baseline scores, (2) to determine if psychological state correlates with baseline performance, and (3) to determine if history of concussion affects Brief Symptom Inventory-18 (BSI-18) subscores of state anxiety, depression, and somatization.

Study Design: Cross-sectional study; Level of evidence, 3.