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An estimated 11% of Canadian adolescents will sustain a sport-related concussion each year. However, diagnostic tools to detect and monitor concussive outcomes are limited.To evaluate the feasibility and test-retest reliability of the Highmark Interactive Equilibrium (HIEQ) test battery in uninjured adolescents.Observational study with repeated measurements.Participants completed the HIEQ test battery, a game-based platform on an iPad application, that assesses balance, cognitive function, and visual function, for up to 15 consecutive school days in a group classroom setting. Feasibility for use of the HIEQ was evaluated by (1) recruitment rates; (2) retention rates; (3) test completion without assistance; and (4) adverse events. Test-retest reliability was examined using Bland Altman 95% limits of agreement and intraclass correlation coefficients comparing the first and second and second and third obtained scores. Reliability across multiple baseline assessments was also analyzed using intraclass correlations for the second to sixth and seventh to eleventh obtained scores.Fifty-five uninjured high school students (31 females and 24 males, mean age = 16.24 [1.09]) from three high schools participated in the study. Three participants (5%) completed all 15 days of testing, and 73% completed at least 10 of 15 test days. No adverse events were reported. Although the test was feasible, all subtests showed wide limits of agreement from first to second and from second to third testing occasions. Results indicate poor-to-moderate reliability (0.50 to 0.75) across those intervals, as well as across the second to sixth and seventh to eleventh testing occasions.The HIEQ is feasible in high school students; however, performance was characterized by wide limits of agreement and poor-to-moderate reliability across test occasions. Future evaluation of the HIEQ in visual and auditory distraction free individual testing settings is warranted.Level 3.

Context After concussion, a multifaceted assessment is recommended, including tests of physical exertion. The current criterion standard for exercise testing after concussion is the Buffalo Concussion Treadmill Test (BCTT); however, validated tests that use alternative exercise modalities are lacking. Objective To evaluate the feasibility and concurrent validity of a universal cycling test of exertion compared with the BCTT in adults who sustained a sport-related concussion. Design Crossover study. Setting University sports medicine clinic. Patients or Other Participants Twenty adults (age = 18–60 years) diagnosed with a sport-related concussion. Intervention(s) Participants completed the BCTT and a cycling test of exertion in random order, approximately 48 hours apart. Main Outcome Measure(s) The primary outcome of interest was maximum heart rate (HRmax; beats per minute [bpm]). Secondary outcomes of interest were the total number of symptoms endorsed on the Post-Concussion Symptom Scale, whether the participant reached volitional fatigue (yes or no), the symptom responsible for test cessation (Post-Concussion Symptom Scale), maximum rating of perceived exertion, symptom severity on a visual scale (0–10), and the time to test cessation. Results Of the 20 participants, 19 (10 males, 9 females) completed both tests. One participant did not return for the second test and was excluded from the analysis. No adverse events were reported. The median HRmax for the BCTT (171 bpm; interquartile range = 139–184 bpm) was not different from the median HRmax for the cycle (173 bpm; interquartile range = 160–182 bpm; z = −0.63; P = .53). For both tests, the 3 most frequently reported symptoms responsible for test cessation were headache, dizziness, and pressure in the head. Of interest, most participants (64%) reported a different symptom responsible for cessation of each test. Conclusions On the novel cycling test of exertion, participants achieved similar HRmax and test durations and, therefore, this test may be a suitable alternative to the BCTT. Future research to understand the physiological reason for the heterogeneity in symptoms responsible for test cessation is warranted.

Pressure data from 20° cone-cylinder models tested in a blowdown wind tunnel for the Mach number range 0.2 to 5.0 are compared to an interference-free standard to determine wall interference effects as a function of test section blockage. Four models representing a range of blockage from approximately 1% to 6% were compared to curve fits of the interference-free standard at each Mach number, and errors were determined at each pressure tap location. The average of the absolute values of the percent error over the length of the model based on an interference-free standard was determined and used as the criterion for evaluating model blockage interference effects. The results are presented in the form of the percent error as a function of model blockage and Mach number.

Brief review of the operational principle and capability of the high-Reynolds-number wind tunnel developed over the last few years. Its test medium is stored in a Ludwieg tube and held there by means of a diaphragm. When the diaphragm is broken, a rearward-facing centered rarefaction fan propagates upstream through the test section and nozzle into the supply tube, and the useful run time is bounded by the reflected rarefaction wave and the starting shock wave caused by choking at the nozzle. The operating problems center around the ability of model and sting support systems to withstand the loads and to meet the instrumentation requirements. Evaluation tests have shown that satisfactory force and moment measurements can be obtained in this facility.