title: Use of the King-Devick test for sideline concussion screening in junior rugby league.
abstract: OBJECTIVE
  To determine whether the King-Devick (K-D) test used as a sideline test in junior rugby league players over 12 matches in a domestic competition season could identify witnessed and incidentally identified episodes of concussion.
  
  
  METHODS
  A prospective observational cohort study of a club level junior rugby league team (n=19) during the 2014 New Zealand competition season involved every player completing two pre-competition season baseline trials of the K-D test. Players removed from match participation, or who reported any signs or symptoms of concussion were assessed on the sideline with the K-D test and referred for further medical assessment. Players with a pre- to post-match K-D test difference >3s were referred for physician evaluation.
  
  
  RESULTS
  The baseline test-retest reliability of the K-D test was high (rs=0.86; p<0.0001). Seven concussions were medically identified in six players who recorded pre- to post-match K-D test times greater than 3s (mean change of 7.4s). Post-season testing of players demonstrated improvement of K-D time scores consistent with learning effects of using the K-D test (67.7s vs. 62.2s).
  
  
  CONCLUSIONS
  Although no witnessed concussions occurred during rugby play, six players recorded pre- to post-match changes with a mean delay of 4s resulting in seven concussions being subsequently confirmed post-match by health practitioners. All players were medically managed for a return to sports participation.
  
  
  CONCLUSIONS
  The K-D test was quickly and easily administered making it a practical sideline tool as part of the continuum of concussion assessment tools for junior rugby league players.
authors.affiliation: Sports Performance Research Institute New Zealand (SPRINZ) at AUT Millennium, Faculty of Health and Environmental Science, Auckland University of Technology, Auckland, New Zealand; Department of Paramedicine, School of Clinical Sciences, Faculty of Health and Environmental Sciences, Auckland University of Technology, New Zealand. Electronic address: dking@aut.ac.nz.
authors.forename: D
authors.initials: D
authors.lastname: King
authors.affiliation: Sports Performance Research Institute New Zealand (SPRINZ) at AUT Millennium, Faculty of Health and Environmental Science, Auckland University of Technology, Auckland, New Zealand.
authors.forename: P
authors.initials: P
authors.lastname: Hume
authors.affiliation: School of Sport Health and Applied Science, St. Mary's University, Twickenham, Middlesex, United Kingdom.
authors.forename: C
authors.initials: C
authors.lastname: Gissane
authors.affiliation: Australian College of Physical Education, Faculty of Human Performance, Sydney Olympic Park, New South Wales, Australia.
authors.forename: T
authors.initials: T
authors.lastname: Clark
mesh_terms: D001265:Athletic Injuries / Q000175:diagnosis*; D001924:Brain Concussion / Q000175:diagnosis*; D002648:Child; D005260:Female; D005538:Football; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011446:Prospective Studies; D015203:Reproducibility of Results
keywords: Brain injury; Eye-movement; Saccadic; Vision