To determine the test–retest correlation of an objective eye-tracking device among uninjured youth athletes.
Healthy youth athletes (mean age = 14.6 ± 2.2 years; 39% women) completed a brief, automated, and objective eye-tracking assessment.
Participants completed the eye-tracking assessment at 2 different testing sessions.
During the assessment, participants watched a 220-second video clip while it moved around a computer monitor in a clockwise direction as an eye tracker recorded eye movements. We obtained 13 eye movement outcome variables and assessed correlations between the assessments made at the 2 time points using Spearman's Rho (rs).
Thirty-one participants completed the eye-tracking evaluation at 2 time points [median = 7 (interquartile range = 6–9) days between tests]. No significant differences in outcomes were found between the 2 testing times. Several eye movement variables demonstrated moderate to moderately high test–retest reliability. Combined eye conjugacy metric (BOX score, rs = 0.529, P = 0.008), the variance of the ratio for both eye movements in the horizontal (rs = 0.497, P = 0.013) and vertical (rs = 0.446; P = 0.029) movement planes along the top/bottom of the computer screen, and the variance of the left and right eye movement along the bottom segment of the computer screen (rs = 0.565; P = 0.004) each demonstrated moderate between-test correlations.
Automated and quantitative eye movement and conjugacy metrics provide relatively stable measurements among a group of healthy youth athletes. Thus, their inclusion as a visual tracking metric may be complementary to other visual examination techniques when monitoring concussion recovery across time.
*Sports Medicine Center, Children's Hospital Colorado, Aurora, Colorado;
†Department of Orthopedics, University of Colorado School of Medicine, Aurora, Colorado;
‡The Micheli Center for Sports Injury Prevention, Waltham, Massachusetts;
§Division of Sports Medicine, Department of Orthopaedics, Boston Children's Hospital, Boston, Massachusetts;
¶Sports Medicine and Performance Center, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania;
‖University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania; and
**Department of Pediatrics and Orthopaedic Surgery, Harvard Medical School, Boston, Massachusetts.
Corresponding Author: David R. Howell, PhD, Department of Orthopedics, ATC Sports Medicine Center, Children's Hospital Colorado, University of Colorado School of Medicine, 13123 E 16th Ave, Aurora, CO 80045 (David.Howell@ucdenver.edu).
D. R. Howell's research has been funded, in part, through a research contract between Boston Children's Hospital, Cincinnati Children's Hospital Medical Center, and ElMindA Ltd. W. P. Meehan receives royalties from (1) ABC-Clio publishing for the sale of his books, Kids, Sports, and Concussion: A guide for coaches and parents, and Concussions; (2) Springer International for the book Head and Neck Injuries in Young Athlete; and (3) Wolters Kluwer for working as an author for UpToDate. His research is funded, in part, by philanthropic support from the National Hockey League Alumni Association through the Corey C. Griffin Pro-Am Tournament and by a grant from the Football Players Health Study at Harvard University, which is funded by the NFL Players Association.
The authors report no conflicts of interest.
Received October 03, 2017
Accepted March 08, 2018