A Comparison of Dynamic Vision Between College Athletes & Controls

The purpose of this study is to establish baseline reference values for tests of static and dynamic visual acuity and gaze stabilization in collegiate athletes and non-athletes, and to determine if there are differences in vision scores between collegiate athletes and non-athletes with and without a history of concussion.

Study Overview

• Status: Completed
• Conditions: Concussion, Brain; Dynamic Vision Tests
• Intervention / Treatment: Diagnostic test: Dynamic Vision Testing

Detailed Description

An IRB-approved human subjects study (IRB-FY 20-339) was designed to investigate dynamic vision pre-and post-concussion in collegiate athletes. In addition to examining if there are changes in objective tests of dynamic vision after concussion, it is important to determine if there are baseline differences in dynamic vision objective tests when comparing collegiate athletes and similar-aged controls. Dynamic vision will be assessed through the administration of the Dynamic Visual Acuity (DVA) test and the Gaze Stabilization Test (GST). Baseline testing of GST and DVA is performed using the Bertec Vision Advantage TM system. Athletes are eligible to participate if they are currently enrolled students, actively participating on specified teams, provide consent to participate, and are able to complete the testing protocol. Non-athlete control subjects are students enrolled in a Doctor of Physical Therapy (DPT) program and serve as a sample of convenience.

• Study Type: Observational
• Enrollment (Actual): 145

Contacts and Locations

Study Locations

• United States
  • California
    • Northridge, California, United States, 91330-8411
      • California State University, Northridge, Jacaranda Hall 1578, 1576, 1574

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Subjects were eligible to participate if they were currently enrolled DPT students, provided consent to participate, and were able to complete the testing protocol.

Description

Inclusion Criteria:

• Currently a California State University Northridge student
• Provide consent to participate Able to complete the testing protocol.

Exclusion Criteria:

• Unable to complete entirety of testing protocol.
• The subject is unable to attain a minimum of 85 degrees per second of horizontal head rotation when performing the DVA test.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Non-athlete college students with and without history of concussions; Non-athlete subjects included students currently enrolled in a Doctor of Physical Therapy (DPT) program served as a sample of convenience. Non-athlete subjects were excluded if they were over the age of 30 years old to minimize the effect of age in the data analysis.	Diagnostic test: Dynamic Vision Testing; Dynamic Vision Acuity is tested with the Dynamic Vision Acuity (DVA) and Gaze Stabilization Test (GST) using the Bertec Vision Advantage System.; Other Names: DVA; GST
Students athletes with and without history of concussions; D1 student athletes currently enrolled in a large public university in the Los Angeles area. Subjects volunteered to participate in this study and currently competing in one of the following teams: Men's and Women's soccer, Men's and Women's basketball, Women's water polo or Men's volleyball. Athletes were eligible to participate if they were currently enrolled students, actively participating on the specified teams, provided consent to participate, and were able to complete the testing protocol.	Diagnostic test: Dynamic Vision Testing; Dynamic Vision Acuity is tested with the Dynamic Vision Acuity (DVA) and Gaze Stabilization Test (GST) using the Bertec Vision Advantage System.; Other Names: DVA; GST

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dynamic Visual Acuity (DVA)	Subjects move their head at approximately 85 degrees per second per the standard test protocol. A metronome automatically generated by the computer assists in maintaining the correct head speed. When the sensor identifies 85 deg/sec, an optotype appears on the screen and the subject verbally identifies the optotype's orientation. This continues with progressively smaller sized letter until the athlete is no longer able to correctly identify the orientation. The computerized system uses a convergence algorithm to determine the accuracy of the response requiring 3 correct answers at the smallest letter size to assign a result. The computer then compares each subject's DVA score to their SVA, which is expressed a Log of minimal angle resolvable units (LogMAR). Simply, the computer considers the number of lines on an eye chart that are lost with head moving (DVA) compared to the head steady condition, known as static visual acuity (SVA)	August 31, 2021 - May 15, 2024

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gaze Stabilization Test (GST)	The subjects are asked to move their head in the horizontal plane and identify an optotype's orientation at increasing speeds. The optotype remains the same size while the head speed increases. A metronome is utilized to ensure correct head speeds which change throughout the test. When the subject reaches or exceeds the minimum threshold for velocity as measured by a wearable gyroscope attached to the forehead, the optotype appears on the screen for 75 ms, and the subject verbally identifies the direction of the optotype. The subject answers 3 of 5 trials correctly to confirm visual acuity for that velocity. The velocity of head movement begins very slowly (10 deg / second) and the rotational speed increases incrementally as long as the subject is asymptomatic and can see clearly. The test continues until the subject "fails", meaning the subject is unable to answer 3 of 5 trials correctly at a given velocity. The maximum head velocity is measured in degrees/second	August 31, 2021 - May 15, 2024
Static Visual Acuity (SVA) test	The SVA tests the subject's ability to see clearly with their head held still, similar to reading a Snellen eye chart. An optotype is briefly flashed on the screen and the subject is asked to correctly identify its orientation (which directing the capital "E" is facing) as it gets progressively smaller. Once the subject gives an inaccurate answer, the computer ends the test and provides their SVA baseline value based on the smallest optotype they could identify.	August 31, 2021 - May 15, 2024

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dynamic Visual Acuity (DVA)	Log of minimal angle resolvable units (LogMAR). The number of lines on an eye chart that are lost with head moving (DVA) compared to the head steady condition, known as static visual acuity (SVA)	August 31, 2021 - May 15, 2024

Collaborators and Investigators

• Sponsor: California State University, Northridge
• Investigators: Principal Investigator: Aimie Kachingwe, Dr., CSUN; Principal Investigator: Margaret Roller, Dr., CSUN

Study record dates

Study Major Dates

• Study Start (Actual): August 31, 2021
• Primary Completion (Actual): May 15, 2024
• Study Completion (Actual): May 15, 2024

Study Registration Dates

• First Submitted: April 6, 2023
• First Submitted That Met QC Criteria: April 6, 2023
• First Posted (Actual): April 19, 2023

Study Record Updates

• Last Update Posted (Actual): July 10, 2026
• Last Update Submitted That Met QC Criteria: July 8, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Baseline Dynamic vision Testing
• Additional Relevant MeSH Terms: Brain Injuries, Traumatic; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Wounds and Injuries; Craniocerebral Trauma; Trauma, Nervous System; Head Injuries, Closed; Wounds, Nonpenetrating; Brain Injuries; Brain Concussion
• Other Study ID Numbers: IRB-FY23-271

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No