Controlled DTI Evaluations in High School Football and Female Soccer to Evaluate Efficacy of Jugular Compression Collar
Phase: NA
Conditions: MTBI - Mild Traumatic Brain Injury, Concussion, Mild
Sponsor: Children's Hospital Medical Center, Cincinnati

CINCINNATI CHILDREN’S HOSPITAL MEDICAL CENTER 
 
 
STUDY TITLE: Controlled DTI evaluations in High School Football and Female Soccer to 
evaluate efficacy of jugular compression collar 
 
NCT #04068883 
 
IRB Approval Date:  02/19/2020 
Protocol Version 8 
 

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CINCINNATI CHILDREN’S HOSPITAL MEDICAL CENTER
STUDY TITLE: Controlled DTI evaluations in High School Football and Female Soccer to 
evaluate efficacy of jugular compression collar
INVESTIGATOR INFORMATION:
Gregory D. Myer, PhD
(513) 636-0249
Principal Investigator Name
Telephone Number
(1) ABSTRACT:
Significant morbidity, mortality, and related costs are caused by traumatic brain injury (TBI). 
A simple, effective, and lightweight device worn by athletes or war fighters in the field, 
designed to mitigate TBI resulting from blast trauma or concussive events, would save lives, 
and the huge costs incurred for life-treatment of surviving victims. An externally-worn medical 
device that applies mild jugular compression according to the principle of the Queckenstedt 
Maneuver (the Device) is being developed by Q30 Sports Science, LLC (Q30) (Figure 1). 
Preliminary research indicates that the Device has the potential to reduce the likelihood of 
alterations to brain microstructure. The currently developed collar has been approved for 
studies in humans and the results indicate safety for use during high demand and maximal 
exertion activities, Study IDs: 2013-2240, 2016-7948, 2014-5009, 2016-9625, 2016-0988, and 
2015-2205   Institutional Review Board - Federalwide Assurance #00002988) (Myer, Yuan et 
al. 2016, Myer, Yuan et al. 2016, DiCesare, Barber Foss et al. 2017, Yuan, Leach et al. 2017, 
Yuan, Barber Foss et al. 2018, Yuan, Dudley et al. 2018). FDA has determined that this device 
is a nonsignificant risk (NSR) device study because it does not meet the definition of a 
significant risk (SR) device under § 812.3(m) of the investigational device exemptions (IDE) 
regulation (21 CFR 812). 
This study will investigate the effectiveness of this device 
in high school athletes playing a collision sport such as 
football or soccer. Athletes participating in this study will 
be randomly assigned to one of two groups: 1) Device 
wearing during the season or 2) Non-device wearing 
during the season. Male football players and female 
soccer players will be included in this investigation.  All 
participants may be outfitted with an accelerometer which 
will measure the magnitude of every impact to the head 
sustained by the athlete. This accelerometer will be affixed  with an adhesive patch,(which will 
be placed behind the ear, to measure the magnitude of every impact to the head sustained by 
the athlete Effectiveness of the device will be determined via differences in longitudinal brain 
imaging and behavioral assessments following competitive football and soccer participation.  
We will also enroll a group of athletes involved in a non-contact sport (such as cross-country) 
to act as controls.
(2) PURPOSE OF STUDY:
Figure 1: Collar Device

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The purpose of the study is to monitor longitudinal changes in brain structure between the 
preseason and postseason, in a population of football and soccer playing athletes wearing the 
Device and compared to a similar population not wearing the device. Secondly, the purpose is 
to determine the efficacy of device to reduce alterations in brain structure relative to amount 
and magnitude of sustained head impacts. Finally, to show that DTI efficacy and safety results 
can be prospectively confirmed in a multi-school investigation.  
Test the null hypotheses of no difference between collar users and non-collar users changes 
from baseline to end of season for:
•
Primary: Alterations in pre-defined DTI metrics (AD, MD, RD) are significantly 
reduced in the neck collar group at EOS relative to BL. 
•
Secondary: Alterations in pre-defined DTI metrics is explained by the number of 
hits, the hit intensity, and the intensity per head impact over the season non-collar 
users.
(3) BACKGROUND:
Summary of Prior Work: Pre-Clinical Trials 
Prior to the onset of in vivo clinical trials, animal studies (rat) of slosh mitigation showed 
that venous compression in the neck applied during a standardized mild TBI model (Marmarou, 
Foda et al. 1994) significantly reduced the extent of axonal injury.(Smith, Bailes et al. 2012) Extent 
of axonal injury was determined by quantification of amyloid precursor protein (APP) 
immuno-histological staining. Figure 2 shows the rat device in situ, and a summary of the 
results of this study. In addition, further analysis in the same rat brains showed that established 
histological biomarkers of TBI (Woodcock and Morganti-Kossmann 2013) were reduced in parallel with 
slosh mitigation.(Turner, Naser et al. 2012) In this study, we observed a 48.7%–59.1% 
reduction in degenerative neurons, a 36.8%–45.7% decrease in reactive astrocytes, and a 
Figure 2. A. Corticolspinal tracts stained for APP after experimental injury. B. Quantification of 
axons staining for positive APP, expressed per mm
3 C. Investigational device utilized. No 
observable changes in behavior were noted following collar application.

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44.1%–65.3% reduction in microglial activation, all of which indicate a significant reduction 
in inflammatory response and neuronal damage after mTBI attributable to jugular vein 
compression. 
At the request of the FDA, an investigation 
was conducted to alleviate concerns of 
increasing the propensity for hemorrhage and 
hemorrhagic propagation with applied jugular 
vein compression. This study aimed to test the 
safety of IJV compression in a large animal 
controlled cortical impact (CCI) injury model 
and the resultant effects on hemorrhage. Twelve 
swine were randomized to placement of a 
bilateral IJV compression collar (CCI+collar) or 
control/no collar (CCI) prior to CCI injury. A 
histological 
grading 
of 
the 
extent 
of 
hemorrhage, both subarachnoid (SAH) and 
intra-parenchymal (IPH), was conducted in a 
blinded manner by two neuropathologists. Other various measures of TBI histology were also 
analyzed including: b-amyloid precursor protein (b-APP) expression, presence of degenerating 
neurons, extent of cerebral edema, and inflammatory infiltrates. Euthanized 5 h after injury, 
the CCI+collar animals exhibited a significant reduction in total SAH (p = 0.024–0.026) and 
IPH scores (p = 0.03-0.05) compared with the CCI animals. There was no statistically 
significant difference in scoring for the other markers of TBI (b-APP, neuronal degeneration, 
cerebral edema, or inflammatory infiltration). In conclusion, IJV compression was shown to 
reduce hemorrhage (SAH and IPH) in the porcine CCI model when applied prior to injury 
(Figure 3).  These results suggest the role of IJV compression for mitigation of not only axonal, 
but also hemorrhagic injury following TBI.
Summary of Prior Work: Clinical Trials
Prior to the initiation of clinical trials, the BIC research team employed a large scale 
epidemiologic investigation to evaluate a potential mechanism by which brain slosh dynamics 
can be controlled via physiologies that occur during acclimatization to altitude such as 
increased diphosphoglycerate, red cell mass, intracranial pressure and volume (the intent was 
to see if the latter two adaptations, which also occur with the jugular compression device in 
place, might be protective against TBI). The investigations were approved by the local IRB 
and was completed in the Cincinnati Children’s Hospital Human Performance Laboratory 
(Study ID: Waiver). The first study evaluated 5,936 concussions that occurred in 20,618,915 
exposures reported by athletic trainers from a large national sample of United States high 
schools to evaluate the effect of 
topographical elevation from nearly 
sea level to nearly 7,000 ft. We 
hypothesized that in the chronic 
phases of adaptation at topographical 
elevation erythropoietin (Epo) will 
have 
increased 
blood 
synthesis 
Figure 3. Representative hemorrhage from whole 
brain gross pathology of (A) controlled cortical 
impact (CCI) and (B) CCI+collar  swine brain. (C) 
Depiction of anatomical sectioning (10 total plus 
sections from bilateral thalami) in relation to CCI 
injury site.
Figure 4 (A) Random-effects model using all available data (4 studies); 
(B) Fixed-effects model of included American football studies 
demonstrating the effect of increased altitude on reduced concussion 
incidence.

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TABLE 2: Association between topographical elevation and concussions in high school football:  Dichotomous 
topographical elevation categories are (low altitude) 0-644 ft, and (high altitude) >645 ft.  The National High School 
Sports-Related Injury Surveillance System, U.S., 2005/06-2011/12 
Practice
Competition
Total
Practice
Competition
Total
# of concussions
585
876
1,461
511
795
1,306
# of athletic exposures (AE)
1641185
330311
1,971,496
1,867,735
380,625
2,248,360
Rate per 10,000 AE
3.56
26.52
7.41
2.74
20.89
5.81
RR
1.3
1.27
1.28
referent category referent category referent category
95% CI
1.16, 1.47
1.15, 1.40
1.18, 1.37
p-value
<0.001
<0.001
<0.001
Low Altitude
High Altitude
leading to relative polycythemia. Our results indicate that the increased topographical elevation 
may contribute to an internal cranial environment that is protective to the brain against 
concussion in both practice and competition. Specifically, elevated topographical elevation 
was associated with a reduction in concussion rates overall (RR=1.31; p <0.001), in 
competition (RR=1.31; p <0.001) and in practice (1.29; p <0.001).(Smith, Myer et al. 2013) In 
a high school football population specific to the current pivotal study proposal, we also found 
a significant reduction in practice related, competition and total reported concussions (Table 
2).(Smith, Myer et al. 2013) In a follow-up investigation, in professional football players, there 
was a statistically significant and clinically lower incidence of concussions for games played 
at altitudes above 644 feet.(Myer, Smith et al. 2014) Relative to game field elevation, there 
was a 30% reduced odds of concussion when playing at higher elevation compared to playing 
a game at lower elevation. The results of this study in professional athletes are consistent with 
the results of the previous study on high school football players.(Smith, Myer et al. 2013, Myer, 
Smith et al. 2014) To summarize the effect of all existing data, a recent and more encompassing 
meta-analysis was performed and published (Figure 4). 
Safety testing in athletes has been approved by the local IRB and was completed in the 
Cincinnati Children’s Hospital Human Performance Laboratory (IRB Study ID: 2013-2240; 
Clinicaltrials.gov: NCT02901028). Evaluation of monitored vital signs, biomechanics, 
cardiorespiratory capacity, postural control, dynamic stabilization, reactive index, 
concentration and cognition, memory, strength and power in a population of athletes showed 
no statistically significant adverse effect of wearing a mild jugular vein compressive neck 
collar compared to a sham arm band.(Myer, Edwards et al. 2013) Cumulatively, the pre and 
post safety measures indicate that neurologic parameters of executive function, eye-hand 
coordination, 
balance, 
memory, 
strength, 
power, 
oxygen 
uptake, 
cardio-metabolic 
measure and reaction times were unchanged 
following two hours of physical testing wearing 
the collar prototype.(Barber Foss, Clark et al. 
2017, DiCesare, Barber Foss et al. 2017, 
Thomas, Edwards et al. 2017) Acceptance of 
the compression collar was not different in 
physiological biomarker response to the non-
collared condition during maximal oxygen 
uptake and maximum effort power testing 
(Figure 5).(Myer, Edwards et al. 2013) 
FIGURE 5. Physiological testing of the athletes 
while wearing the internal jugular vein compression 
device. Panel A shows the collar being fitted and 
evaluated for jugular pressures. In B, the athlete 
demonstrates that the collar does not impede full 
extension of the arms overhead during maximal 
power testing. C. The collar in place during 
Dynavision and (D), the collar during maximum 
oxygen uptake test.

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Subsequent to the safety testing, Cincinnati Children’s Institutional Review Board and the 
FDA panel determined that clinical investigation with jugular vein compression collar is a 
nonsignificant risk (NSR) device because it does not meet the definition of a significant risk 
(SR) device under § 812.3(m) of the investigational device exemptions (IDE) regulation (21 
CFR 812).(FDA 2016)
An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (IRB Study 
ID: 2016-6895; Clinicaltrials.gov: NCT03236389). Magnetic Resonance Elastography was 
established at CCHMC in collaboration with The Mayo Clinic to support these studies. Under 
jugular vein compression with the collar, all participants tolerated the procedure without any 
untoward effects. Jugular vein compression via a passive collar device is a promising avenue 
for mitigating diffuse traumatic brain injury in collision sports and other impact-prone 
activities. Inspired by similar mechanisms found in woodpeckers and bighorn sheep, in 
principle the reduction of venous return increases intracranial blood volume and consequently 
mitigates the forces involved in coup and countercoup injuries. Here, we employed magnetic 
resonance venography (MRV), 
 
elastography (MRE), and imaging (MRI) to investigate whether the collar can modulate venous 
return, cranial compliance, brain tissue stiffness, and intracranial volume of cerebrospinal fluid 
(CSF). All images were acquired on a 3T GE Discovery system and processed in SPM12. Four 
participants (3 male, 1 female;19-24 years old) received the following neuroimaging battery: 
Figure 6. MRV images show successful restriction of jugular vein flow for cranial responder while also showing 
that recruitment of alternative pathways for venous return was achieved for spinal responder. Cranial responder 
showed increased stiffness as indicated by increased red response while limited increased stiffness (not likely to 
be reflected with cranial MRE) in the spinal responder who utilized alternative pathways for blood flow in 
response to jugular vein compression.

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two 3D T1-weighted scans (1 mm3 isotropic, TR/TE = 8.6/3.2 ms), two 2D MRE scans (1.875 
x 1.875 mm in plane, 3.6 mm slice thickness, TR/TE = 2600/120.7 ms), and two 2D time-of-
flight MRV scans (0.47 x 0.47 mm in plane, 6 mm slice thickness, TR/TE = 13.8/2.4 ms). 
Between repeated acquisitions, participants exited the scanner and put on/removed the collar, 
providing one image of each modality in a “collar-on” and “collar-off” condition. 2D scout 
images were acquired prior to each scan to achieve similar positioning and slice prescriptions 
for all acquisitions. Brain stiffness measures for collar-on and -off conditions were computed 
from the MRE images. On and off condition MRE magnitude images were co-registered for 
each subject using a normalized cross-correlation algorithm and the corresponding calculated 
stiffness images were multiplied by the resulting rigid body transformation matrices. Lastly, 
an 8mm Gaussian smoothing kernel was applied to approximate the effective resolution of the 
MRE scan at 25Hz. To calculate intracranial CSF volume for each subject and condition, the 
T2-weighed MRE magnitude image was co-registered using normalized mutual information 
and resampled to match the T1-weighted MRI scan. Both images were then used to generate 
tissue probability maps of gray matter, white matter, and CSF volume from SPM12’s multi-
channel unified segmentation algorithm. Analyses of these images provide preliminary 
evidence of the proposed protective mechanism of the collar. MRV images showed successful 
restriction of jugular vein flow for responder participants while also showing that recruitment 
of alternative pathways for venous return was achieved for non-responders (Figure 6). 
Notably, stiffness was not substantially changed for non-responder, but was increased for 
responder. Taken together, these multimodal imaging data provide initial, in vivo, evidence 
demonstrating a potential mechanism by which the collar changes the jugular vein blood flow 
and compliance and thus affects the vulnerability of the brain against acceleration/deceleration 
injuries. Furthermore, the differential responses of subjects may indicate a subject representing 
those who do not respond in the same way to the application of the collar in the physical 
properties of the jugular vein. Whether these subjects are representative of two potential 
distinct groups, cranial responder vs. spinal responders” to the collar usage, requires further 
investigation.  For example, there is reasonable logic to presume that just the filling of the 
spinal vertebral venous space could be enough to impart the wanted protective action for the 
cranial space (and MRE would not be able to detect this spinal filling per say). However, the 
data presented in this report is a proof of concept for exploring the potential physiological 
mechanism by which the jugular vein compression helps to improve protection from brain 
injury in contact sports. If our results can be replicated and proved valid in future studies, the 
imaging variables could serve as valuable explanatory markers for real-world studies of collar 
use and ultimately be used as predictors of outcome.
An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (IRB Study 
ID: 2013-5717; Clinicaltrials.gov NCT02262507). We studied 410 participants (ages 12 to 68 
years of age) via a middle ear power analysis (MEPA) with and without the compression collar, 
and no complaints or untoward effects were noted and no declines in the auditory perception 
were recorded. The expected changes of reduced Acoustic Reflectance of the inner ear and 
middle ear (indicative of reduced compliance) were noted only in a subgroup analysis of those 
with jugular vein compression. The results of this study indicate that the neck compression 
collar prototype may have the potential to safely reduce energy impartation into cranial 
structures (i.e., the inner ear); however, further work is needed with advanced collar designs 
to establish this effect. 

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fMRI and CO2 reactivity was performed on 12 adults before and after application of jugular 
vein compression. Results comparing before 
and after jugular vein compressions (with 
the collar) yielded that compression of the 
internal jugular veins in supine healthy 
volunteers increases blood volume in the 
skull 
with 
venous 
blood 
distributed 
particularly to the large venous sinuses. 
Specifically, compression of IJV increases 
the blood volume in venous sinuses, 
observable in particular in the straight and 
sigmoid 
sinuses. 
This 
confirms 
the 
effectiveness of the IJV compression. 
Compression of IJV results in a small, but 
widespread reduction in BOLD signal over 
the brain. This observation is consistent with 
either a decrease in cerebral blood flow or 
increase in volume of deoxygenated blood. A small increase in the BOLD signal seen in the 
middle cerebral artery (MCA) and cerebellum indicated the possibility of a slightly increased 
cerebral blood flow or the accumulation of arterial blood diffusely as well.  Jugular venous 
compression (JVC) does not change the magnitude or distribution of the resting blood flow in 
the brain and does not affect the response of brain blood flow to hypercapnia. This finding 
implies that it would not affect the brain blood flow in response to an increase in demand for 
flow. Further JVC does not reduce the cerebral blood flow CBF if applied during increase in 
flow demand, as simulated in this study by hypercapnia. This finding provides confidence that 
the brain would be able to maintain CBF if the collar is applied under other high flow states 
such as exercise (Figure 7).(Fisher, Duffin et al. 2013)
An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (Study ID: 
2014-5009; Clinicaltrials.gov: NCT02271451). The in vivo clinical trial was performed in 
hockey players of the proposed intervention device used during sporting competitions to test 
its effect in ameliorating neuroanatomical and neurophysiological changes to the brain using 
two widely accepted techniques [(DTI), and 
event related potentials (ERPs) utilizing 
electroencephalography.](Reches, Laufer et 
al. 2014) For athletes in the non-intervention 
group, RD (Song, Sun et al. 2003, Song, 
Yoshino et al. 2005) increased significantly 
from 
pre-season 
to 
mid-season. By 
comparison, the athletes in the intervention 
group did not show a significant change in RD 
with similar accumulated g-force head 
impacts (Figure 8). In kind, ERP analysis 
showed concomitant changes in brain network 
dynamics in the non-intervention group—the 
level of change was strongly correlated with 
 Figure 8 Significant alterations in MD (a) and RD 
(B) from pre- to mid-season in non-collar group 
after accounting for longitudinal changes in collar 
group. The red regions represent areas where the 
increase of DTI measure in the non-collar group 
was significantly larger than that in the collar group, 
p < 0.05 level (FWE corrected). The red regions are 
thickened to improve visual display.
 Figure 7: Mid-brain single slice ASL images for a 
single subject at both normocapnia and 
hypercapnia, with and without the collar. Color 
scale range from 0 to 75 in units of mL/100g/min.

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the accumulated g-force of the collisions, whereas the intervention group showed no significant 
change. These group differences indicate that mild jugular vein compression may provide 
protection from the detrimental effects of collisions and resultant brain injury. These 
prospective longitudinal data utilized an internal (in vivo) approach and demonstrate, for the 
first time, that it is possible to protect the brain from sports related head impacts. (Myer, Yuan 
et al. 2016)
An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (Study ID: 
2015-2205; Clinicaltrials.gov: NCT02696200) The in vivo clinical trial was performed in 
football players implementing the proposed intervention device used during sporting 
competitions to test its effect in ameliorating 
neuroanatomical 
changes 
to 
the 
brain 
evidenced by DTI. Based on pre-clinical data 
we hypothesized that collar, which imparted 
jugular compression that minimally restricts 
venous outflow to encourage cerebral venous 
sinus engorgement, would reduce brain injury 
biomarkers in athletes exposed to head 
impacts during a competitive football season. 
This project utilized a prospective controlled 
trial to evaluate effects of mild jugular vein 
(i.e., neck) compression (collar; n=31) 
relative to controls (no-collar; n=30) during a 
competitive football season (males; 17.04 ± 
0.67 years). Helmet sensors were used to 
collect daily impact data in excess of 20 g 
(games and practices) and the primary 
outcome measures, which included changes 
in white matter microstructure, were assessed 
by 
diffusion 
tensor 
imaging 
(DTI). 
Specifically, four DTI measures including 
fractional anisotropy (FA), mean diffusivity 
(MD), axial diffusivity (AD), and radial 
diffusivity (RD) were analyzed using a Tract-
Based Spatial Statistics (TBSS) approach—a 
voxel based analysis. The final analyses included both an intent to treat (ITT) and per protocol 
evaluation of the collar intervention. The ITT analysis indicated a consistent vascular response 
by the athletes to collar compression, as indicated by internal jugular vein dilation (IJV) 
superior to its application (p< .01). Both groups experienced similar overall g-forces and total 
head impacts during the competitive football season (impacts > 20 g; collar 16983 vs no-collar 
17750 (p>.05). Significant pre- to post-season reduction in MD, AD, and RD (corrected p<.05) 
was evidenced by extensive WM areas in the no-collar group, while no statistically significant 
longitudinal change was indicated for any of the DTI measures in any WM region in the collar 
group. Comparing the two groups, the no-collar group demonstrated significantly larger pre- 
to post-season DTI change in many WM regions (corrected p<.05) (Figure 9). Correlation 
analysis also showed initial evidence of significant correlation between the change in AD in 
 
Figure 9. White matter regions with significant 
within-group AD reduction at postseason compared 
with preseason baseline. The significant regions 
(red-yellow regions, p<0.05, FWE corrected for 
multiple comparisons) were overlaid on to the white 
matter skeleton (green) and standard T1-weighted 
image in MNI 152 space (grey scale). The 
significant regions were filled in using tbss_fill in 
FSL to improve visualisation. Image orientation is in 
radiological convention. AD, axial diffusivity; CTRL, 
control; FSL, FMRIB Software Library; FWE, family-
wise error rate; MNI, Montreal Neurological 
Institute. Top row: no-collar (CTRL) group; bottom 
row: collar group.
No-Collar
Collar

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some WM regions and the number of impacts and/or the cumulative G-force experienced in 
the no-collar group (all p<.05). Per protocol, results were consistent with presented ITT 
findings with an expected increase in effect sizes noted in most voxel analyses. Our findings, 
based on four DTI measures known to relate to brain injury, indicate a consistent reduction of 
change in diffusivity parameters noted in the no-collar group at post-season. This reduction is 
consistent with and repeated in our studies and likely indicative of sub-clinical white matter 
injury due to repetitive head impacts during the competitive season. The smaller and 
statistically non-significant change in diffusivity in the collar group evidences a mitigating 
effect from the induced jugular outflow impedance. Restated, the approach to impede IVJ 
blood flow appears to have ameliorated the detrimental effects that resulted from a season of 
head impacts. The current study presents the first football related prospective longitudinal data 
and demonstrates a novel, in vivo, approach to protect the brain from football related head 
impacts. These results build on prior research and evidence the need for future work to 
determine if this novel method for brain injury prevention is both safe and effective.(Myer, 
Yuan et al. 2016)
An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (Study ID: 
2015-2205; Clinicaltrials.gov: NCT02696200) The in vivo clinical trial was performed in 
football players implementing the proposed intervention device used during sporting 
competitions to evaluate effect of repetitive head impacts on the alteration of neuronal activity 
based on fMRI of working memory after a high school football season; and 2) determine 
whether a neck collar that applies mild jugular vein compression designed to reduce brain 
energy absorption in head impact, through slosh mitigation, can ameliorate the altered fMRI 
activation during a working memory task. Participants were recruited from local high school 
football teams with 27 and 25 athletes assigned to the non-collar and collar group, respectively. 
A standard N-Back task was used to engage working memory in the fMRI at both pre- and 
post-season. The two study groups experienced similar head impact frequency and magnitude 
during the season (all p>0.05). fMRI BOLD signal response (a reflection of the neuronal 
activity level) during the working memory task increased significantly from pre- to post-season 
in the non-collar group (corrected p<0.05), but not in the collar group. Areas displaying less 
activation change in the collar group 
(corrected p<0.05) included the precuneus, 
inferior parietal cortex, and dorsal lateral 
prefrontal 
cortex. 
Additionally, 
BOLD 
response in the non-collar group increased 
significantly in direct association with the total 
number of impacts and total g-force (p<0.05) 
(Figure 10). Our data provide initial 
neuroimaging evidence for the effect of 
repetitive head impacts on the working 
memory related brain activity, as well as a 
potential protective effect that resulted from 
the use of the purported brain slosh reducing 
neck collar in contact sports.(Yuan, Dudley et 
al. 2017)
 Figure 10. Correlation coefficient between the 
pre- to post-season change of brain activation and 
the weekly impact (A: number of hits; B: total g-
force; C: Average g-force) experienced at different 
time prior to the post-season imaging. The X-axis 
denotes the week number before the post-season 
imaging, e.g., -1 represents the last week, and -4 
represents the 4th week prior to the post-season 
imaging.

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An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (Study ID: 
2015-2205; Clinicaltrials.gov: NCT02696200) The in vivo longitudinal clinical trial was 
performed in football players implementing the proposed intervention device used during two 
sporting competitions to quantify the longitudinal persistence of altered white matter (WM) 
integrity observed in one high school football season at 8 months post season and to evaluate 
the long term effects of the jugular vein compression collar designed to ameliorate alterations 
in brain network. Prospective diffusion tensor imaging data from 23 male high school football 
athletes (10 non-collar; 13 collar) were acquired at three longitudinal time points: T1 (pre-
season), T2 (post-season) and T3 (following the off-season). The in-season time interval 
(T1→T2) was 4.24±0.52 months and the off-season interval (T2→T3) was 8.48±0.30 months. 
Tract Based Spatial Statistics approach was used to quantify change in the WM anisotropic 
diffusion properties between these time points. DTI remained unchanged across all time points 
in the collar group. Despite similar number/severity of head impact, the non-collar group 
showed significantly greater reduction than the collar group in mean, axial and radial 
diffusivity between T1→T2 in extensive WM regions (corrected p<0.05). During the 
presumed recovery off-season period without head impact exposure (T2→T3), DTI diffusivity 
values in the non-collar group increased significantly toward baseline, but remained 
significantly lower (T1>T3; all p<0.05). The non-collar group demonstrated WM recovery 
towards baseline during the off-season relative to post-season DTI alterations found following 
the competitive football season. However, the persistence of significantly lower diffusion 
properties (again, in the non-collar group) may be indicative of incomplete WM recovery. The 
lack of significant DTI change over time in the collar group suggests that a mitigating effect 
may be afforded from the applied jugular compression.(Yuan, Barber Foss et al. 2017)
An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (Study ID: 
2015-2205; Clinicaltrials.gov: NCT02696200) To evaluate the collar experience across a high 
school football season, a survey was created and distributed among the football participants. 
The survey was composed of three categories of questions: collar effect on performance, collar 
use and experience, and collar care and storage. Results were received from 31 of the 
participating high school football players to investigate their experiences when using the Q-
Collar during the football season. Football players reported an overall positive experience 
using the collar, feeling an increased sense of protection when wearing the device (0% negative 
responses), perceived improved performance and heightened maximum effort on the field (0% 
negative responses), and most athletes reported that they would continue to wear the device if 
made available in the future (6% negative responses). Players also reported little to no 
discomfort or pain while wearing the device. While this study did not investigate the efficacy 
of the device in reducing mild TBI risk or changes in DTI surrogate endpoints among high 
school football players, it showed that this device is both usable and tolerable among a small, 
selective sample of high school athletes.(Roth, Cohen et al. 2017)
An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (Study ID: 
2015-2205; Clinicaltrials.gov: NCT03014492). It is speculated that females may be at a 
particularly higher risk, prompting a prospective longitudinal controlled cohort study with a 

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novel jugular compression collar to determine its effects on long-term WM changes over three 
time-points spanning 9 months. DTI analyses revealed significant WM changes from pre- to 
post-season in the non-collar group in MD, AD, and RD but no significant change was found 
in the collar group, despite similar quantity and magnitude of head impacts.  Significant 
correlation was found between head impact 
exposure experienced during the season and 
pre- to post-season DTI changes in the non-
collar group. In addition, the WM changes in 
the non-collar group identified at the post-
season time point partially resolved at 3 months 
offseason follow-up but remained significantly 
different when compared to pre-season. In 
conclusion, microstructural changes in WM as 
assessed by DTI were found to occur during a 
single season of high school female soccer 
athletes. These changes occurred in athletes in 
who did not wear the jugular compression 
collar but did not occur in those who wore the 
collar (Figure 11). The mitigated WM 
alterations in athletes in the collar group 
suggested a potential effect of the collar in 
ameliorating the changes against repetitive 
head impacts. In addition, the in-season WM 
alterations were reduced within 3 months post-
season indicating a physiological reversal in 
diffusivity 
changes 
noted 
during 
the 
competitive season in non-collar wearing 
participants.(Myer, Barber Foss et al. 2017)
An in vivo clinical trial was approved by 
CCHMC IRB and was completed in the 
Cincinnati 
Children’s 
Hospital 
Human 
Performance 
Laboratory 
and 
Radiology 
Department (Study ID: 2015-2205; Clinicaltrials.gov: NCT03014492). Recent neuroimaging 
studies have suggested that repetitive sub-concussive head impacts, even after only one sport 
season, may lead to pre- to post-season structural and functional alterations in male high school 
football athletes. However, data on female athletes is limited. In the current investigation, we 
aimed to (1) assess the longitudinal pre- to post-season changes in fMRI of working memory 
and working memory performance, (2) quantify the association between the pre- to post-season 
change in fMRI of working memory and the exposure to head impact and working memory 
performance, and (3) assess whether wearing a neck collar designed to reduce intracranial slosh 
via mild compression of the jugular veins can ameliorate the changes in fMRI brain activation 
observed in the non-collar group after a full soccer season. A total of 48 female high school 
soccer athletes (age range: 14.00 – 17.97 years) were included in the study. These athletes were 
assigned to the non-collar group (n=21) or to the collar group (n=27). All athletes underwent 
MRI at both pre-season and post-season. In each session, an fMRI verbal N-Back task was 
 Figure 11. WM regions with significant group 
difference in the pre- to post-season reduction in 
(A). MD; (B) AD; and (C) RD between the 22 
participants in the non-collar group and the 24 
participants in the collar group who underwent both 
pre- and post-season MRI. The significant regions 
(red-yellow regions, p<0.05, TFCE corrected for 
multiple comparisons) were overlaid on to the WM 
skeleton (green) and standard T1-weighted image 
in MNI 152 space (grey scale). The significant 
regions were filled in using tbss_fill in FSL to 
improve visualization. 
A
B
C

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used to engage working memory. A significant 
pre- to post-season increase in fMRI BOLD 
signal was demonstrated when performing the 
N-back working memory task in the non-collar 
group but not in the collar group, despite the 
comparable exposure of head impacts during 
the season between the two groups (this 
signifies more work, O2 uptake, was needed in 
the non-collared group to perform the same 
function). The collar group demonstrated 
significantly smaller pre- to post-season change 
in fMRI BOLD signal than the non-collar 
group, suggesting a potential protective effect 
from the collar device (Figure 12). Significant 
correlations were also found between the pre- to 
post-season increase in fMRI brain activation 
and the decrease in task accuracy in the non-collar group, indicating an association between 
the compensatory mechanism in underlying neurophysiology and the alteration in the 
behavioral outcomes.(Yuan, Leach et al. 2017)
 Figure 12. Brain regions with greater pre- to post-
season increase in activation in non-collar group 
(n=21) than collar group (n=27, p<0.05, corrected) 
The z value in the upper left corner in all the panels 
represents the z-coordinate in mm. 

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An in vivo clinical trial was approved by CCHMC IRB and was completed in the Cincinnati 
Children’s Hospital Human Performance Laboratory and Radiology Department (Study ID: 
2016-8580; Clinicaltrials.gov: NCT03017937). This clinical study is aimed at determining the 
required minimum pressure at various locations on the neck to cause restriction of outflow of 
blood via the Internal Jugular Veins (IJV) in various targeted populations. The populations 
targeted in this study included males and females 7-60 years of age. Three test devices, each 
corresponding to a range of collar sizes, allowed for a controlled application of pressure to 
both sides of the neck. The 
fixtures were designed to 
universally fit participants 7-
60 years of age and allowed 
local adjustments vertically 
along 
the 
neck. 
Two 
different pad sizes were 
evaluated with the size of 
pad being determined based 
on 
neck 
girth 
and 
corresponding Collar sizes, 
which 
were 
pre-defined. 
Study 
participants 
sat 
upright, and the IJV was 
identified via ultrasound. A 
sonographer 
performed 
vascular 
ultrasonography 
procedures of the neck for 
baseline measurements and 
sonographic images of the IJV on both sides with IJV compression. To address the first aim, 
the test fixture was applied to the participant’s neck, with no pressure applied. The pressure 
was increased in increments of 0.1 +/- 0.025 lb. until the test fixture reads ~0.5 lb. IJV 
dimensions were captured and labeled based on the minimum pressure measured and the 
location of the test fixture. The second aim was addressed by applying new Q-collars of known 
force to the test participant, and confirming dilation of the IJV superior to the point of pressure, 
using ultrasound. This process included applying collars corresponding to the measured size, 
one size above and one size below the fitted collar. Data was captured on hard copy case report 
forms (CRFs), in an electronic database, and as sonographic images. IJV dilation compared to 
baseline was visually confirmed by registered vascular technologist, and the force applied by 
the test collar at the lowest responsive level was recorded. Following this subjective 
measurement, length, width and area of the responsive IJV was measured, using the ultrasound 
software, and a % difference was measured compared to baseline. IJV response to the Q-collar 
was also collected, measured, and compared to baseline. Visually confirmed forces 
corresponding to IJV dilation indicated a response of the IJV to the test collar and Q-collars. 
These responses were confirmed by measurements. The results indicated a positive response 
in >90 of study participants at 0.2 lb of IVJ pressure and that optimal response as evidence by 
IJV distention was noted in fitted collar (Figure 13). The results of the current project indicate 
a universal response to IJV distention and the benefits of proper collar fitting to optimize IJV 
response.
 Figure 13. Internal jugular vein response to differential pressure 
applications of the tested collars.

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Evidence from a previous pilot study indicates that repetitive head impacts from sports leads 
to changes beyond chance in three pre-defined DTI metrics (AD, MD, and RD) in student 
athletes.  
This study aims are to: 
•Determine whether a neck collar that applies mild jugular vein compression designed to 
reduce brain energy absorption in head impact by evaluating three pre-defined DTI derived 
metrics following a full season.
•Control for and correlate with head impact exposure with the three pre-defined DTI 
metrics.
•Confirm collar user placement and compliance.
•Confirm collar user safety.
(4) STUDY DESIGN:
The current project will be a prospective longitudinal study design as well as to include 
retrospective data from a previous study (IRB #2018-2799, entitled Evaluation of Helmet 
Technology and Head Impact Exposure). The subjects in 2018-2799 underwent the same 
testing as subjects in the current study and thus incorporating the data from the previous study 
will strengthen the results from the current study.  All MRI scanning will be performed on a 3 
Tesla Philips Achieva MRI scanner located in Imaging Research Center (IRC) in the Cincinnati 
Children’s Hospital Research Foundation (CCHRF). Sedation will not be used for any of the 
test visits. The entire MRI series, which may include anatomical imaging, DTI, resting-state 
fMRI, and magnetic resonance spectroscopy (MRS) will take less than 45 minutes  (see Table 
3 for detailed specifications). 

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Table 3. Image sequence, mode and analysis. Imaging will be completed in 30 minutes or less. 
Sequence
Resolution
Mode
Analysis
Time 
(min)
3D T1
1x1x1 mm
Anatomy
Visual /Volumetrics/registration
5
DTI
2x2x2 mm
WM microstructure
Visual/ROI/TBSS/structural connectivity
12
fMRI
2.5x2.5mm
Blood Flow
Functional Connectivity
5
MRS
Single Voxel
Neural Integrity
Neurometabolic function of M1
5
MRS
Single Voxel
Neural Integrity
Neurometabolic function of DLPFC
5
MRS
Single Voxel
Neural Integrity
Neurometabolic function of ACC
5
Total Time
~37 min
(5) DURATION:
The study recruitment and intervention will occur during one season. Each participant will 
participate in 2 planned study visits that may take up to 1 hour. Data analysis will continue for 
a 2 year period following the final enrollment. 
(6) SELECTION & RECRUITMENT OF PARTICIPANTS:
We will recruit up to 500 study participants (250 per sport). The participants (age 13-19 years 
old) will be recruited from local school districts. Participants will be recruited using a top-
down approach. We have gained the consent and the cooperation of the school district 
administrations. Presentations and letters from the research team will be given to each 
participating school to detail the participation requirements and study risks. Questions 
regarding participation will be answered during the presentations or through e-mail or phone. 
Participants will be contacted via telephone or email to further explain the study, answer any 
additional questions and to enroll them in the study. Participants also have the option of 
completing an electronic eligibility screener.  Qualifying participants may then choose to 
provide their contact information for research staff to contact them about potential 
participation.  The demographic forms will be distributed to parents to complete at the 
coaches/parent meeting or when the subject is enrolled.  The participants and parents/guardians 
who voluntarily agree to participate will be scheduled to complete the pre-participation testing. 
The participant and parent/guardian will read and sign the “Consent to Participate in a Research 
Study” form, approved by the Institutional Review Board of Cincinnati Children’s Hospital. If 
the participant and parent/guardian does not read or sign the form, they will not participate in 
the study. Once the potential school teams are identified, they will be randomized to one of 
two groups: 1) Device wearing during the season or 2) Non-device wearing during the season. 
This research does not mandate that the participant maintains participation in their sport. The 
desire to participate in the sporting event is an independent, personal decision separate from 
the decision to enter into this study. If any athlete choses to stop participation in the sporting 
activity then they will also be withdrawn from the study, due to no longer meeting inclusion 
criteria. We will also enroll a group of athletes involved in a non-contact sport (such as cross-
country) as no head impact controls (N=40). 

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Inclusionary criteria include:

Normal healthy volunteer 

Able to provide written consent

Must be 13 years or older and a participant on a high school football or soccer team
Exclusionary criteria include: 

Unable to provide written consent

History of neurological deficits, previous cerebral infarction, or severe head trauma as 
indicated through pre-season screening:

Medical contraindications to restriction of venous outflow via the internal jugular veins 
(known increased intracerebral pressure, metabolic acidosis or alkalosis)

Glaucoma (Narrow Angle or Normal Tension)

Hydrocephalus

Recent penetrating brain trauma (within 6 months)

Known carotid hypersensitivity

Known increased intracranial pressure

Central vein thrombosis

Any known airway obstruction

Any known seizure disorder

Prothrombotic or hyperthrombotic condition

Cerebral cavernous malformation

Players not medically cleared to play sports
Waiver of Documentation For all potential participants that are invited and/or screened by 
phone, mail, e-mail or eScreener, we are requesting a waiver of documentation of consent for 
the Screening Phase of the study. Screening and questionnaire completion are minimal risk 
activities and typically done in the clinical setting without consent. Completion of the 
eligibility screen and questionnaires prior to the participant’s arrival will decrease the overall 
time spent in the study visit.
(7) PROCESS OF OBTAINING CONSENT
Once a participant is identified as a potential participant, is contacted by a CCHMC/Sports 
Medicine representative and verbally agrees to participate, the process to obtain consent will 
begin. A copy of the informed consent will be provided to the participant at this time. The 
study coordinator will review the informed consent and the participant will have an opportunity 
to ask any questions regarding the study and/or the study protocol. At that time, the participant 
will be given time to decide whether or not they wish to participate and if so, asked to sign the 
informed consent. Once the signature is obtained, the participant will be given a copy of the 
consent and testing will commence. At no time will the participant be coerced into 
participation. Receiving the informed consent prior to enrollment will allow the participants to 
review the study information prior to participation in the study. This will aid the participant to 
make an informed, unforced decision regarding election to participate in the study.

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Because we will be testing teens, we will be using the Parent Consent Form to obtain both the 
participant assent and the parent consent. The participants and their parents will be given 
adequate time to review the study materials and ask questions. If they choose to participate, 
the patient and parent will sign the IRB approved consent forms. It will be made clear to the 
patient and their parents that participation in the study is voluntary.   Subjects aged 18 and over 
will complete the Adult Subject consent form.
In the event that a parent or guardian will not be present at the scheduled testing appointment, 
consent/assent forms will be provided ahead of time for review for those subjects under age 
18. The coordinator will ensure that all necessary forms have been signed prior to any data 
collection.
Parents of study participants may complete a brief behavioral rating scale that assesses 
symptoms of ADHD (See Procedures section).  We will send parents a link via email for them 
to complete this questionnaire via a REDCap online survey.  This questionnaire will take no 
longer than 5-10 minutes for the parent to complete. The Concussion in Sport Group panel has 
recognized numerous mTBI “modifiers” (e.g., sex, age, ADHD) that can impact the severity 
of the mTBI and course of recovery. The presence of ADHD has been associated with greater 
likelihood of mTBI occurance, as well as experiencing multiple mTBIs.  An ADHD diagnosis 
is also associated with worse symptom severity and prolonged course of mTBI symptom 
recovery, compared to non-ADHD cohorts.  However the effects of ADHD on repetitive head 
impacts and sub-clinical threshold head impact exposure is unknown.  The current study will 
help uncover the potential effect of co-morbid ADHD on the study outcomes.
(8) STUDY PROCEDURES:
      Study Visit and Brain Imaging-Performed at CCHMC Imagining Research Center may 
contain the following tasks:
MR imaging data Acquisition
Magnetic Resonance Imaging (MRI), including sequences outlined in Table 3 are all based on 
the concept of using magnetic fields and radio waves to make chemical, anatomical and 
physiological assessments with in the living tissue. This technology has been utilized for 
diagnostic and research purposes since the early 1980s. 
This testing will consist of a minimum of 2 MRI sessions (preseason, and post season) all 
inside a 3T scanner at the CCHMC Imaging Research Center. During the acquisition of MR 
images, the study participants will lie on the scanner table. For most portions of MR 
acquisition, the study participants will only be instructed to lie still. For other parts of the 
acquisition, study participants will be asked to answer questions that will assess their cognitive 
ability and working memory. Participants will be allowed to communicate with the MR 
operator via an always-on, two-way intercom at any time. In addition, the participants have a 
hand-held air ball to squeeze in the event that they elect to be removed from the magnet 
immediately. The study participants have control over their presence in the magnet, which in 
turn tends to minimize feelings of claustrophobia. As magnetic resonance imaging employs 
the use of strong magnets, patients will receive a standard preoperative screening questionnaire 

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regarding the potential for ferromagnetic objects within their bodies to ensure their safety 
during the study. 
Participants will be screened for MRI specific contraindications such as:
•
Braces or permanent metal dental work
•
Insulin pump
•
Cardiac pacemaker
•
Cochlear implants
•
Hearing aids
•
Aneurysm clips
•
Orthopedic pins, wires, screws, or plates
•
Any other exclusionary criteria as documented on the MRI safety screening poster 
included with recruitment materials
Those participants with any aforementioned contraindication will be excluded from the 
imaging portion of the study but will still be eligible to participate in the rest of the study 
procedures.  
Functional Assessments of Neurovisual endpoints. 
The MRI data will provide anatomic and inferred functional information concerning putative 
brain changes pre to post season. Additional and complimentary functional information will 
be obtained using following neurofunctional tests. These are outlined below. 
1. Visual Evoked Potential (VEP). 
2. Timed Saccades. 
VEP: VEP is a method to assess the relative time and voltage involved in a flash to each eye 
individually and the response received at the occipital lobe. It is based on 
electroencephalogram (EEG) technology. The VEP accumulates 100 flashes and averages the 
responses obtained. The primary outcome measures are the N75 and P100 latencies and the 
signal amplitude as measured by the Reteval system (Roland systems Chicago IL). The system 
uses a hand held device that flashes light in one eye at a time and measures the responses. It is 
capable of doing multiple colors of light, in this case it will flash white light. A total of three 
EEG type Electrodes are placed relative to bony landmarks (mid forehead, lambda suture and 
inion.  For electrode placement, the surface of the scalp is cleaned using NuPrep abrasive skin 
prep gel at the location of each electrode. Surface electrodes are fixed to the scalp using 
Conductive Neurodiagnostic Electrode Paste and standard surgical tape. Signal averaging is 
automatically processed by the system and stored on the hand held device and downloaded to 
a computer for further analysis. No mydriatic solution is used. The test is performed 
monocularly by placing an opaque patch over the unstimulated eye. The covered eye is kept 
open and hidden from light throughout the test.  
Saccades: Saccadic eye movement is a critical component for activity of daily living, 
especially for school aged individuals who are reading and studying. We will use the 10 x 10 
saccadic eye charts.

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The subject reads alternating columns going down. So for the figure above the person would 
read: B, L, 2, V, F, 4 etc. The conclusion of the test is when the subject reads H, G. The test is 
timed and the time recorded. The result from the test is a time in seconds. 
King Devick Test: The K-D test involves reading aloud a series of single digit numbers from 
left to right on three test cards. Standardized instructions will be used and the test requires less 
than 2 min to administer. Specifically, participants will perform a timed, two-minute test 
wherein participants are asked to read aloud single digit numbers separated by lines and arrows 
printed on test cards. This test will be performed twice. The test cards become more 
challenging as the spacing between numbers becomes more variable. The K–D test will include 
one demonstration card and three test cards. Participants will be asked to read the numbers on 
each card from left to right as quickly as possible but without making any errors. The sum of 
the three test card time scores will be used to create a summary score for the entire test. In 
addition the numbers of errors made in reading the test cards are also recorded.3   The fastest 
time will be recorded.
Near Point Convergence: We will assess near point of convergence (NPC) on all participants 
in order to compare these measurements with the oculomotor measurements. The NPC is a 
measurement that pertains specifically to visual fusion. Fusion is a visual term that refers to 
binocular vision. More specifically, fusion pertains to combining the image from the left and 
right eye synchronously to produce a single image. NPC is the closest point in space for which 
an individual can hold visual fusion. NPC is measured by bringing an object close to the nasal 
bridge. Once that image becomes blurry or double vision ensues, this is marked as the NPC 
break (measured in centimeters from the nasal bridge). NPC recovery can also be measured as 
the distance from the nasal bride when binocular vision ensues. Normal NPC break in youth is 
reported to be 5-6 cm with NPC recovery being 7-9 cm.NPC will be measured using a Gulden 

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Near 
Point 
Rule 
(http://www.guldenophthalmics.com/products/index.php/near-point-
rule.html). The rule is placed on the patient’s forehead with accommodation card at eye level. 
The accommodation card is brought towards the patient’s nasal bridge. When the patient 
reports that he or she can no longer maintain binocular single vision (object becomes blurry), 
this is marked as the NPC break (distance from nasal bridge to accommodation card measured 
in centimeters). The NPC recovery is measured when the accommodation card is brought away 
from the nasal bridge. When binocular single vision is resumed, this is marked as the NPC 
recovery (distance from nasal bridge to accommodation card measured in centimeters).
Cognitive Testing:
Cued task switching. Participants are instructed to match a stimulus presented in the upper 
center of the screen to one of two stimuli in the lower left and right corners of the screen. In 
task-homogeneous (i.e., single task) blocks, participants match the upper stimulus to shape 
only (Task A) or color only (Task B). There will be 6 blocks. Participants switch between the 
two tasks (A, B) pseudo-randomly during task-heterogeneous (i.e., mixed) blocks. Each 
block contains 12 trials. Each trial will last for approximately 3700-ms. Presentation of task 
block type will be CACCBC. Participants will be instructed which type of task to complete 
prior to each block. The cued task switching task will take approximately 7 minutes to 
complete.
Digital Trail Making Test (dTMT).  The digital version of the Trail Making Test is nearly 
identical and uses the same instructions to the standard paper version with the exception  of 
replacing ‘pencil’ for ‘stylus’ and ‘page’ for ‘screen.’ Both parts of the dTMT consist of 
circles distributed over a tablet screen laid flat on a table. In Part A, the circles are numbered 
1 – 20, and the participant should draw lines to connect the numbers in ascending order. In 
Part B, the circles include both numbers (1 – 10) and letters (A – H); as in Part A, the 
participant draws lines to connect the circles in an ascending pattern, but with the added task 
of alternating between the numbers and letters (i.e., 1-A-2-B-3-C, etc.). The participant is 
instructed to connect the circles as quickly as possible, without lifting the stylus from the 
tablet screen. The dTMT is an Android-based app that was created to automatically extract 
participant performance features (see Dahmen, Cook, Fellows, and Scmitter-Edgecomb, 
2005) including number of errors, time to completion, number of pauses, average pause 
duration, number of lifts, average lift duration, time inside each circle, and time between 
circles. Timing begins as soon as the stylus makes contact with the tablet screen and stops as 
soon as the last circle is touched. If the wrong circle is entered a red X is presented over the 
circle and the administrator informs the participants that a circle was skipped and to return to 
the last circle. The dTMT (both parts) will take 5 minutes. 
Flanker Task. The flanker task assesses the orienting, alerting, and executive/conflict 
attention networks. Each trial begins with a central fixation cross. The target array is a set of 
five arrows presented horizontally in the center of a computer screen. The participant is to 
respond based on whether the central arrow is pointing to the left or right by pressing the 
corresponding left or right key on the mouse. On congruent trials the flanking arrows are 
pointing in the same direction, on incongruent trials the flankers point in the opposite 
direction from the central arrow, and on neutral trials the central arrow appears alone. Each 
target is preceded by one of four warning cue conditions: a center cue, a double cue, a spatial 

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cue, or no cue. In the center cue condition, an asterisk is presented at the location of the 
fixation cross. In the double cue condition, an asterisk appears at the locations of the target 
above and below the fixation cross. Spatial cues involve a single asterisk presented in the 
position of the upcoming target. A session of the ANT consists of a total of 24 practice trials 
and one experimental blocks of 96 trials in each.  Participants indicate their responses via a 
right or left keyboard button-press. Accuracy and reaction time are recorded. Each trial 
begins with a fixation period of a random variable duration of between 400 and 1600ms. 
Subsequently, on some trials a warning cue is presented for 150ms. A brief fixation period of 
450ms appears after the disappearance of the cue, followed by either the simultaneous 
appearance of the target and flanker, or by the appearance of the target alone. This display 
remains on the screen until a response is detected, to a maximum of 1700ms. After 
responding, the participant receives auditory and visual feedback from the computer. This 
task will take 5 minutes to complete.
Postural Sway Task: Participants will be asked to stand upright on a force platform. The 
force platform is a noninvasive device that measures the ground reaction forces produced 
during upright stance. Specifically, participants will be asked to stand comfortably with their 
arms at their side for a minute for two trials. Once with their eyes open and once with their 
eyes closed.  There are no potential risks beyond those experienced during everyday upright 
bipedal stance (e.g., fatigue, falling, etc.).  There are no direct benefits for the participants; 
however, participants may indirectly benefits from the opportunity to investigate the 
relationships among motor control, concussions, and brain activation.
Questionnaires:  
Strength and Weaknesses of ADHD-Symptoms and Normal-Behavior scale (SWAN):  Parents 
and study participants may complete a brief behavioral rating scale that assesses symptoms of 
ADHD via a REDCap online survey to be completed prior to the MRI scanning session.  
Parents that do not attend the MRI session with the research participant will be sent a link via 
email for them to complete this questionnaire. This questionnaire will take no longer than 5-
10 minutes to complete.  This will be completed at both the pre and post-season appointments 
and post-concussion.  The SWAN consists of 18 items to measure ADHD symptoms. The 18 
DSM-5 ADHD symptoms in the SWAN rating scale have been adapted to measure attention, 
as opposed to inattention, and positive impulse control, instead of lack of impulse control. 
Participants rate items on a seven point scale (1 = “far below average,” 2 = “below average,” 
3 = “slightly below average,” 4 = “average,” 5 = “slightly above average,” 6 = “above average,” 
7 = “far above average”).
PCSI: Parents and study participants will complete the Post Concussion Symptom Inventory 
(PCSI) form at the MRI screening session at both pre and post-season.  The PCSI is used to 
assess for mTBI symptom severity at baseline and post-testing and post-concussion.  The PCSI 
is comprised 20 questions assessing common symptoms of mTBI. Symptoms were rated on a 
seven point scale ranging from 0 (“not a problem”) to 6 (“severe problem”). Four factor scores 
are derived by summing items on each factor: Physical (8-items; e.g., “complains of 
headaches”), Fatigue (3-items; e.g., “sleeping more than usual”), Emotional (4-items; e.g., 
“acts irritable”), Cognitive (5-items; e.g., “has difficulty concentrating”) symptoms.

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Exposure Questionnaire:  Study participants may complete a brief REDCap survey to collect 
the participant’s previous exposure to contact or collision sports.  The Exposure Questionnaire 
is based on the subject’s participation in school- or club-based sports in their lifetime. 
Participants were asked to select sports they have participated in any sport from a list sports 
with a high risk of concussion. For each sport the participant selected, they were asked at which 
ages they participated in the identified sport and for how many hours per week they participated 
in that identified sport.  This online survey will be completed prior to the MRI scanning session.  
This questionnaire will take no longer than 5-10 minutes to complete.  This will be completed 
at the pre-season appointment only.
TBI History Questionnaire: Parents and study participants will complete a brief REDCap 
survey to collect participant’s history of TBI.  The TBI History Questionnaire assesses the 
lifetime history of traumatic brain injury (TBI). The questionnaire elicits recall of head or neck 
injuries requiring medical attention, as a result of a motor vehicle accident, or from falling or 
getting hit by something or someone. For each identified head or neck injury incident, the 
participants are asked if they experienced (1) a loss of consciousness and for how long (i.e., 
<30 minutes, 30mintues to 24 hours, >24 hours), (2) feeling dazed or a gap in their memory 
from the injury and for how long, (3) nausea, vomiting, severe headaches, memory problems 
and/or dilated eyes and for how long, and (4) if they missed any school/work or other activities 
because of these symptoms.  This will be completed at the pre-season appointment only.
If participants fail to complete any portion of the questionnaires during their study visit, we 
will contact them via email to obtain this missing information.
Injury Surveillance
Device and Compliance Acceptance: The study coordinator will be responsible for providing 
the appropriate intervention (device or no-device) to each team based on their random 
assignment prior to the season onset. At first fitting of the collar a registered vascular 
technologist will utilize ultrasound to ensure that the collar fits correctly and is activated as 
prescribed. Following the initial fitting, each athlete will receive adequate instruction on how 
to properly use the device on a daily basis. Throughout the season, the coordinator will make 
routine visits to each team to monitor the proper usage and fitting of the device, tracking the 
use of the device by each athlete individually.  At the end of practice/game the device will be 
collected by the athletic trainer and/or stored in the athlete’s locked locker.  The device is not 
to go home with the athlete.
 
Head Impact Surveillance and Follow-up: All players will wear an accelerometer (CSx 
Systems, Auckland, New Zealand) to measure the magnitude of each head impact sustained 
by the subject.  The accelerometers are equipped with electronics that allow for the 
measurement of linear accelerations and rotational velocities of the head.  The accelerometer 
measures six degrees of freedom by directly measuring three axes relative to linear acceleration 
and three axes relative to angular velocity.  The accelerometer stores all data locally for 
uploading to a computer.  De-identified impact data are transmitted to a cloud-based server, 

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accessible only to the study research team via a unique username and password.  All impacts 
greater than a preselected threshold between 15-20 g-force will be recorded and utilized in the 
postseason analyses.  If available, video of games and practices will be used to validate and 
confirm head impacts recorded by accelerometers.  Accelerometer tracking and management 
will occur at every game and practice by the study research team.
The study participants will also be monitored on a weekly basis for athletic exposures for a 
single season. The data secured regarding each athlete’s participation in individual practices 
and games combined with accelerometer exposure to impacts allows the research team to 
capture robust individual athlete exposures rather than just combined team exposures.
The athletic trainer will evaluate any athlete for whom a concussive event has been observed 
(within 24 hours). Should the MD concur with the AT on a positive evaluation, a diagnosis of 
isolated concussion is made and the athlete is removed from play and participant is referred 
for to a post-concussion evaluation. 
Post-concussion and post season testing consists of the same battery of tests as performed for 
pre-season testing, which allows for direct comparison between typical and concussed data. 
Concussion follow-up:  The data collection for this study was completed successfully as 
proposed in the original IRB.  We collected neuroimaging data from over 400 participants at 
both pre-season and post-season. For those who experienced concussion, we also collected 
neuroimaging data soon after the concussion. During the 2018 football and soccer season, a 
total of 41 participants experienced concussion.  From our preliminary data analysis, we have 
found significant pre-season to post-concussion changes in the brain network and we also 
found that the collar wearing at the time of concussion showed significant mitigating effect to 
these changes. The initial finding has been reported in a recent abstract submitted to a scientific 
meeting (see reference below).  In the present amendment, we propose to conduct follow-up 
scans in these children with concussion experienced in the past sports season before the new 
sports season starts. Our goal is to quantify the degree of abnormality preserved in these 
athletes before the new season starts. The progression of the change observed in brain network, 
from post-concussion, to post-season, and then the follow-up at approximately 6-9 months 
after injury, will allow us to generate significant data critical for future prospective extramural 
grant applications focusing on the sports related concussion and recovery. We will use the 
same MRI protocol as in the original study. The MRI protocol will include the following 
sequences: 3D T1w, DTI, rs-fMRI, and MRS, which will be approximately 40 minutes in total 
in scan time. All the sequence specifications will remain unchanged. No sedation will be used 
during the scan. In addition to the MRI scan, we will also collect information regarding 
participation in contact sports between the end of last season and the proposed follow-up scans.  
Myer GD, Barber Foss KD, Dudley JA, Diekfuss JA, DiCesare CA, Logan K, Leach JL, Yuan W. 
Brain white matter alteration in structural integrity and connectivity following a sports-related 
concussion: evaluation of the potential ameliorating effect of a jugular vein compression collar 
device. The 7th Annual Meeting for Pediatric Research in Sports Medicine Society, Glendale, 
Arizona, January 23-25, 2020. Submitted.

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Following the competitive season/end of study participation, the collar study device will be 
returned to the study coordinator.  No participant will be allowed to keep the study device once 
study participation has concluded.
(9) DATA ANALYSIS/METHODS:
Data Storage. 
The personal demographic data for each participant will be blinded from the researchers, and 
a coded identification number will be used to track all collected data. Data will be stored on 
password-protected computers and only pertinent research personnel will have access. Data 
forms will be stored by coded identification number in a locked cabinet to which only pertinent 
research personnel have access. All data will be collected for research purposes only.
Statistical Analysis. 
All analyses will be conducted according to a prospectively approved Statistical Analysis Plan. 
All analyses will be conducted in accordance with ICH E6 under pre-existing standard 
operating procedures. All analyses will be performed using SAS Version 9.1 or later. A two-
sided p=0.05 is required to reach statistical significance.
All effectiveness data is expected to be continuous. Intra-group comparisons will be analyzed 
using a one-sample t-test while all inter-group comparisons will be analyzed using a two-
sample t-test. Group differences will be tested using ANCOVA; baseline covariates include 
group, age, cumulative playing time, hit counts, hit intensity, and intensity per hit. Results will 
be presented for FA as well, but no FA effectiveness claims will be made.
All players will be included in all analyses to the fullest extent possible, consistent with the 
intent-to-treat principle. Repeated measures will be used to simultaneously evaluate the three 
pre-defined DTI metrics (AD, MD, RD). 
Subgroup analyses will be performed for those playing >50% of all possible minutes for the 
position played as well as collar compliance, players dropping out due to injury or other 
reasons, and motion artifacts. 
Data processing and analysis will be performed using a series of existing software including 
FSL (FMRIB’s Diffusion Toolbox in FSL Software, Oxford, UK), AFNI (Cox, 1996) , SPM 
(Statistical Parametric Mapping analysis package, Wellcome Department of Cognitive 
Neurology, London, UK), DTIStudio (John Hopkins University, Baltimore, MD; Jiang et al., 
2006), as well as additional customized software written in Matlab or IDL. 
DTI data will first be subjected to preprocessing to correct for Eddy current and head motion 
artifact, followed by calculation of the three diffusion eigenvectors and eigenvalues. DTI 
measures, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), 
and radial diffusivity (RD) will be calculated. The regions of interest will be manually 
determined in major white matter areas such as corpus callosum, internal capsule, and external 
capsule. After being normalized to a common template, voxel based group analysis can be 

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performed to explore brain regions that present significant group difference or longitudinal 
changes. Fiber tracking can be performed to generate white matter tracts in different areas in 
the brain, e.g., cortico-spinal tract, different segments in corpus callosum, optic radiation, 
cingulum superior longitudinal fasciculus, and others. 
Statistical considerations. The following calculations summarize the effect sizes which can be 
detected with the proposed sample size per intervention (collar users, non-collar users). The 
mean difference between collar users and non-collar users will be of primary interest. Effect 
sizes >1 are expected for each of AD, MD, and RD.
Soccer:
Group Specific: With 40-60 subjects per group subset (separately for collar users and not collar 
users), the following intra-group deteriorations (BL->EOS) can be detected with 90% power 
and two-sided 5% Type I error; small (<0.3) effect sizes for the change from baseline within a 
group (either non-user change or no collar user change) can be detected; a 15% loss can be 
accommodated to retain 80% power:
 One group t-test: Mean change = 0
90% Power
Reach Significance
1
2
3
4
 Test significance level, α
0.050
0.050
0.050
0.050
 1 or 2 sided test?
2
2
2
2
 Effect size, E =|mA-m0|/SDW
0.526
0.425
0.318
0.257
 Power (%)
90
90
NA
NA
 N
40
60
40
60
Group Comparisons: With 40-60 subjects per group, the following inter-group comparisons 
(at EOS) can be detected with 90% power and two-sided 5% Type I error; a moderate (0.3-
0.5) effect size for the treatment difference will result in reaching statistical significance for 
testing the above pre-specified hypotheses (a pre-specified treatment group difference at a pre-
specified time); a 15% loss can be accommodated to retain 80% power:

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Two group t-test: Mean difference = 0 (equal n's)
90% Power
Reach Significance
1
2
3
4
 Test significance level, α
0.050
0.050
0.050
0.050
 1 or 2 sided test?
2
2
2
2
 Effect size, E=|m1-m2|/SDB
0.734
0.597
0.444
0.361
 Power (%)
90
90
NA
NA
 n per group
40
60
40
60
Type 1 Error Control: There will be multiple effectiveness endpoints which require Type I 
error control for multiple comparisons. Hierarchical strategies will be used. The overall Type 
1 error is two-sided p=0.05.  The primary hypotheses for the three pre-defined DTI metrics 
(excluding FA) will first be assessed. All three pre-defined DTI metrics must each achieve 
statistical significance in order to achieve study success.  Based on historical data, there are 
many factors (compliance, mouth braces, MR head motion, not making sports team, sports 
related injury) that limit final per protocol follow-up assessments, therefore we will recruit up 
to 250 soccer athletes to ensure adequate sampling to support the study aims.
 
Football:
It is assumed that each school will have 48-72 participating players allowing a comparison of 
48-72 players using the neck collar vs. 48-72 players not using the neck collar. 
Group Specific: With 48-72 subjects per cohort-group subset (separately for collar users and 
not collar users), the following intra-group deteriorations (BL->EOS) can be detected with 
90% power and two-sided 5% Type I error; small (<0.3) effect sizes for the change from 
baseline within a group (either non-user change or no collar user change) can be detected; 15% 
loss can be accommodated to maintain 80% power:
 One group t-test: Mean change = 0
90% Power
Reach Significance
1
2
3
4
 Test significance level, α
0.050
0.050
0.050
0.050
 1 or 2 sided test?
2
2
2
2
 Effect size, E =|mA-m0|/SDW
0.478
0.387
0.289
0.234
 Power (%)
90
90
NA
NA
 N
48
72
48
72
With 48-72 subjects per group, the following inter-group comparisons (at EOS) can be detected 
with 90% power and two-sided 5% Type I error; a moderate (0.3-0.5) effect size for the 
treatment difference will result in reaching statistical significance for testing the above pre-
specified hypotheses (a pre-specified treatment group difference at a pre-specified time); a 
15% loss can be accommodated to retain 80% power:
 

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Two group t-test: Mean difference = 0 (equal n's)
90% Power
Reach Significance
1
2
3
4
 Test significance level, α
0.050
0.050
0.050
0.050
 1 or 2 sided test?
2
2
2
2
 Effect size, E=|m1-m2|/SDB
0.669
0.544
0.404
0.329
 Power (%)
90
90
NA
NA
 n per group
48
72
48
72
Non-Head Impact Controls:
Based on the overall study, effect sizes indicated in the 2-sample t-tests, we will enroll and 
monitor 40 non head impact control participants (e.g. cross country) involved in training 
exercise to evaluate with the contact sport athletes The comparisons for the athlete group in 
non-contact sports will be used to account for the potential brain change resulting from exercise 
so that the change in the non-collar contact-sport athletes can be attributed to head impact 
experienced during the season.
Type 1 Error Control: There will be multiple effectiveness endpoints which require Type I 
error control for multiple comparisons. Hierarchical strategies will be used. The overall Type 
1 error is two-sided p=0.05. The primary hypotheses for the three pre-defined DTI metrics 
(excluding FA) will first be assessed. All three pre-defined DTI metrics must achieve statistical 
significance in order to achieve study success.  Based on historical data, there are many factors 
(compliance, mouth braces, MR head motion, not making sports team, sports related injury) 
that limit final per protocol follow-up assessments, therefore we will recruit up to 250 football 
athletes to ensure adequate sampling to support the study aims.
Statistical analysis of outcomes measures will be done using SAS®, version 9.3 (SAS Institute, 
Cary, NC) and SPSS statistical software (SPSS Inc, Chicago IL). Comparisons between the 
testing conditions (collar vs. no collar) will be made using Analysis of Covariance, in order to 
control for time (pre vs post season) and condition (collar versus no collar).  We will also 
conduct correlation analysis to test the association between imaging biomarkers (as described 
above) with the results obtained from the impact surveillance. The collision indices, including 
total number of collisions, number of collisions from front, back, left, right, top, bottom, G 
force, and timing of each collision will all be recorded and tested in the analysis. Secondary 
analysis to compare the intervention with no intervention and calculate the rates would involve 
a Poisson model, using an offset to account for the playing time and exposure to concussive 
impact for each of the study participants. We will calculate the rate and the associated 95% 
confidence interval. SAS®, PROC GENMOD will be used for analysis, which allows us to 
account for the fixed and random effects, use the appropriate link function, and the offset for 
amount of playing time exposure.
For additional data analysis with a larger sample size, de-identified from Study 2018-2799 
will be combined with this dataset.  Data were collected with identical methods in order to 
support aggregate analysis of associated outcomes. Our rationale to include a larger sample 

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from 2018-2799 is to provide more robust results to the scientific community. Neuroimaging 
analyses require large sample sizes as ‘trending or preliminary findings’ often do not reach 
significance due to corrections for multiple comparisons (1000’s of analyses require very 
conservative p values). More specifically, a larger sample size will provide us the opportunity 
to identify additional white matter regions with new features (location, volume, direction of 
DTI change) and their association with head impact exposure (linear and rotational 
acceleration).
(10) FACILITIES AND PERFORMANCE SITES:
All MRI scanning will be performed on a 3 Tesla Philips Achieva MRI scanner located in 
Imaging Research Center (IRC) in the Cincinnati Children’s Hospital Research Foundation 
(CCHRF). Sedation will not be used for any of the test visits. The entire MRI series, including 
anatomical imaging, 3d T1, DTI, will be completed in 30 minutes or less (see Table 1. for 
detailed specifications). 
(11) POTENTIAL BENEFITS:
Participants of this study will not receive any direct or immediate benefits by completing this 
study. However, they will be contributing to research involving the potential for major 
contributions to future TBI/concussion prevention strategies.
(12) POTENTIAL RISKS, DISCOMFORTS, INCONVENIENCES AND PRECAUTIONS:
The Device partially circumnavigates and compresses the neck in the same way that a 
compression garment (non-medical apparel) behaves, and very similar to the compression 
exerted by a necktie (although this device is open over the trachea and can be pulled off if 
inadvertently gripped). These garments have been shown to gently facilitate natural response 
mechanisms in several small neck muscles and tendons (the Omohyoids), which are 
universally present in mammals and birds.
The physiologies imparted by these Omohyoids (and further facilitated by these garments) 
merely approximate natural physiologies, which occur when individuals lie in the prone, or 
supine position, and are also comparable to the simple act of yawning (which has been shown 
to collapse the jugulars). The Device will intentionally deliver an exacting, but gentle 
compression to the Omohyoid muscles in the neck allowing these muscles to optimize blood 
outflow of the neck vasculature. In the upright position (without the collar), the resultant 
vascular blood column siphons volume out of the neck, rapidly, creating a negative pressure 
on the cranium and resulting in a slight “under filling” and “sloshability” inside the skull.
The Omohyoid muscle raises the volume of the intracranial space by design. The Device does 
not contain any inherently rigid structures in its design. Similarly, neckties circumnavigate the 
neck, and safely raise intracranial pressure and volume comparable to the Device. The Device 
is manufactured of a soft rubber similar material and should be barely noticeable to the wearer. 
Careful MRI studies have confirmed an increase in blood volume in the brain but have also 
shown that there is no significant change in brain blood flow pattern with wearing a “tight 
necktie” (Rafferty, Quinn et al. 2010). 
Evaluation of monitored vital signs, biomechanics, cardiorespiratory capacity, postural 
control, dynamic stabilization, reactive index, concentration and cognition, memory, strength 

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and power in a population of athletes showed no statistically significant adverse effect of 
wearing a mild jugular vein compressive neck collar compared to a sham arm band.(Myer, 
Edwards et al. 2013) Cumulatively, the pre and post safety measures indicate that neurologic 
parameters of executive function, eye-hand coordination, balance, memory, strength, power, 
oxygen uptake, cardio-metabolic measure and reaction times were unchanged following two 
hours of physical testing wearing the collar prototype.(Barber Foss, Clark et al. 2017, 
DiCesare, Barber Foss et al. 2017, Thomas, Edwards et al. 2017) Acceptance of the 
compression collar was not different in physiological biomarker response to the non-collared 
condition during maximal oxygen uptake and maximum effort power testing
Considering the above mentioned findings on jugular compression, this device can be 
considered not to meet the definition of a “significant risk device,” as that term is defined in 
21 C.F.R. § 812.3(m).
MR Imaging of the Brain: The risk the magnetic fields and the strengths, and radio waves is 
vanishingly small. Some patients can experience anxiety from the confined space of the 
magnet’s bore. Therefore people with known claustrophobic tendencies will be excluded from 
the study. Another minor concern when using magnetic resonance technology is the noise the 
magnet makes when collecting data. Noise abatement measures are used; headphones and 
music with a selection of music options. Ferrous implants and or piercings can be affected in 
the magnetic field. Therefore participants will be advised to remove these and or scanned with 
a metal detector to screen for such objects. 
Our colleague’s previous experience with MRI experiments (who will be present and has a 
decade of experience with this technology) has provided confidence that there should be no 
psychological, physical, legal, or social risks involved with MRI experiments in general, 
though participants may be anxious about the scan, possibly causing them slight stress. The 
MRI scanning will be performed using the 3 T Siemens Trio MRI scanner. MRI does not 
involve ionizing radiation and scans up to 8 T are considered as non-significant risk. The risks 
common to all MRI scans can be described as: (1) ferromagnetic objects introduced into the 
magnetic field, (2) confinement in the scanner bore, (3) radio-frequency (RF) heat deposition 
in tissue which is monitored by the system to conform with FDA guidelines, and (4) acoustic 
noise. These risks are addressed below: Participants are allowed to communicate with the MR 
operator via an always-on, two-way intercom at any time. In addition, the participants have a 
hand-held air ball to squeeze in the event that they elect to be removed from the magnet 
immediately. Thus, the participants have control over their presence in the magnet, which in 
turn tends to minimize feelings of claustrophobia. 
The MR imaging will be initially reviewed by a licensed radiologist just as it would be if it 
were being used as part of routine medical care. There is a possibility that while reviewing MR 
images we may see an abnormality that we did not expect to see in this study. In this event, we 
will notify the participant’s legal representative (or participant is 18 years or older) if we see 
such an incidental finding. Depending on the type of incidental finding, we may contact the 
participant by mail or by phone. A member of the research team will discuss the incidental 
finding with the legal representative (or participant if over the age of 18 years). If the 
participant chooses, we will give information about this incidental finding to their primary 

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doctor or we will refer them to an appropriate doctor for further evaluation. The costs for any 
care that will be needed to diagnose or treat an incidental finding would not be paid for by this 
research study.
Data Storage. There is also a minimal risk that the data collected for each participant may be 
viewed by individuals outside the research team. The risk that confidential data may be viewed 
is relevant for both the written forms and electronic databases. Precautions, such as password-
protected computers, locked cabinets and coded identification numbers, are in place to 
minimize this risk.
Adverse Events. During the course of the investigation, injuries consistent with the sports being 
monitored are expected to occur (E.g. concussion, musculoskeletal injury, bone fractures). 
Care of all injuries will follow standard of care as directed by the team’s athletic trainer and/or 
the participants treating physician. CCHMC will not be responsible for the medical treatment 
of any injuries that are not directly related to wear of the Q-collar device. In the case of an 
adverse event that is determined to be directly related to the wear of the Q-collar during 
competitive play, the principal investigator will report such event to Cincinnati Children’s 
Hospital Medical Center IRB as any future funding organizations in a manner consistent with 
the requirements of each organization. As described in the consent, if a participant believes 
they have sustained an injury as a result of the study then they are instructed to contact the 
principal investigator or director of social services who in turn will then contact CCHMC IRB 
and necessary funding institutions, as aforementioned. If a participant sustains an injury during 
testing they will be referred to the most appropriate medical facility or seek medical attention 
by the physician/medical specialist of their choice.
(13) RISK/BENEFIT ANALYSIS:
Participants will be approached for participation via the appropriate method. The purpose and 
the study protocol will be fully explained in conversation and with the informed consent 
process. 
On the day of the study, the investigators will confirm that the volunteer participant has no 
health impairment as outlined in the exclusion criteria. Time will be taken to repeat the aims 
of the study, test protocol, and to answer any remaining questions posed by the participant.
The methods described in this protocol have been used extensively in previous testing in the 
laboratory. During previous testing, there have been no reported injuries, adverse events or 
complications. Additionally, the investigators have considered potential risk for injury and 
have taken additional steps, described in the protocol, to minimize these risks. 
A study participant may be withdrawn from the investigation if they demonstrate repeated 
alteration in their proper football tackling technique, such as adoption of spearing tackling 
tendencies. Subject participation will also be halted should an adverse event while wearing the 
collar, such as syncope, occur. Any adverse events will be immediately reported. The safety 
officer will evaluate all adverse events and will determine if early stopping of the study due to 
safety concerns is warranted. Given the study design and sample, we do not deem futility or 
efficacy stopping rules are warranted.

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(14) DATA SAFETY & MONITORING:
The Safety Officer will act in an advisory capacity to the Principal Investigator (PI) to monitor 
patient safety and progress for the clinical trial, and will be the contact person for severe 
adverse event reporting.
The Safety Officer’s responsibilities are to:
•
review the research protocol, informed consent documents and plans for data safety 
and monitoring;
•
evaluate the progress of the trial, including periodic assessments of data quality and 
timeliness, participant recruitment, accrual and retention, participant risk versus 
benefit, performance of the trial site, and other factors that can affect study outcome;
•
consider factors external to the study when relevant information becomes available, 
such as scientific or therapeutic developments that may have an impact on the safety of 
the participants or the ethics of the trial;
•
review study performance, make recommendations and assist in the resolution of 
problems reported by the PI;
•
protect the safety of the study participants;
•
report to the PI on the safety and progress of the trial; 
•
make recommendations to the PI concerning continuation, termination or other 
modifications of the trial based on the observed beneficial or adverse effects of the 
treatment under study;
•
ensure the confidentiality of the trial data and the results of monitoring; and, assist the 
PI by commenting on any problems with study conduct, enrollment, sample size and/or 
data collection.
The Safety Officer and PI will hold meetings to review the data safety, the first of which will 
be held prior to initiation of the trial to discuss the protocol, approve the commencement of the 
trial, and approve the plans for monitoring the study. Meetings with the safety officer will be 
determined by the PI and will be closed to the public because of confidentiality considerations. 
An emergency meeting may be called at any time by the Safety Officer, or by the PI, should 
questions of participant safety arise.
This research study involves only minimal risk for participants (see Risk/Benefit Analysis 
section (15)). Further assurances regarding participant safety and protection of private and 
confidential participant information have been outlined in the Potential Risks, Discomforts, 
Inconveniences and Precautions section (14), the Privacy section (18) and the Confidentiality 
section (19). If during the, preliminary analyses the research team identifies strong evidence 
of harm from the Q-collar device the study will be stopped immediately.
(15) PRIVACY AND CONFIDENTIALITY:
The participant has the right to privacy. The investigators will protect participant privacy to 
the extent allowed by law. All facts about this study that can describe a participant’s name will 
be kept private. Results of the study will be summarized regarding age, etc. but the 
investigators will take every precaution necessary to keep names private. 

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To maintain the privacy information of study participants, only pertinent research personnel 
will have access to participant information. Research personnel are employees of CCHMC and 
have been trained in human participants research and HIPAA compliance. To further insure 
privacy, all data will be analyzed and tracked using a coded identification number that does 
not use identifiable personal information. Personal information and identifiers will be securely 
recorded and filed by the administrative assistant. The data will be encrypted with a password 
and stored on a personal computer and backed up on a network drive. The participant 
identification code will be used on all data questionnaires.
The results of this study will be kept confidential. No participant identification will be made 
public record in any form unless the participant gives his or her expressed written permission 
of release of participant’s name, photograph or likeness captured on video. The investigators 
will be available for any questions that may arise.
To further insure confidentiality, only pertinent research personnel will have access to 
participant information. Research personnel are employees of CCHMC and have been trained 
in human subjects research and HIPAA compliance. 
(16) COST OF PARTICIPATION:
Participants will endure no costs other than time and effort in participating in this study. 
Insurance will not be billed for any of the tests associated with this study.
(17) PAYMENT FOR PARTICIPATION:
Participants will be compensated for their time and effort in participating in this study. They 
will receive a $50 Clincard Mastercard® gift card for completing the first testing session and 
a $100 Clincard Mastercard® gift card for completing the final testing session. Participants 
who sustain a clinically diagnosed concussion will also receive $50 for each completed session 
following new concussion diagnosis.

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Myer, G. D., K. D. Barber Foss, S. Thomas, R. T. Galloway, C. DiCesare, J. Dudley, B. Gadd, J. 
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Myer, G. D., D. Smith, K. D. Barber Foss, C. A. Dicesare, A. W. Kiefer, A. M. Kushner, S. M. 
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