title: Assessment of the King-Devick® (KD) test for screening acute mTBI/concussion in warfighters.
abstract: OBJECTIVE
  The Department of Defense reported that 344,030 cases of traumatic brain injury (TBI) were clinically confirmed from 2000 to 2015, with mild TBI (mTBI) accounting for 82.3% of all cases. Unfortunately, warfighters with TBI are often identified only when moderate or severe head injuries have occurred, leaving more subtle mTBI cases undiagnosed. This study aims to identify and validate an eye-movement visual test for screening acute mTBI.
  
  
  METHODS
  Two-hundred active duty military personnel were recruited to perform the King-Devick® (KD) test. Subjects were equally divided into two groups: those with diagnosed acute mTBI (≤72h) and age-matched controls. The KD test was administered twice for test-retest reliability, and the outcome measure was total cumulative time to complete each test.
  
  
  RESULTS
  The mTBI group had approximately 36% mean slower performance time with significant differences between the groups (p<0.001) in both tests. There were significant differences between the two KD test administrations in each group, however, a strong correlation was observed between each test administration.
  
  
  CONCLUSIONS
  Significant differences in KD test performance were seen between the acute mTBI and control groups. The results suggest the KD test can be utilized for screening acute mTBI. A validated and rapidly administered mTBI screening test with results that are easily interpreted by providers is essential in making return-to-duty decisions in the injured warfighter.
authors.affiliation: Vision Protection and Performance Division, U.S. Army Aeromedical Research Laboratory, 6901 Farrel Rd, Fort Rucker, AL 36362, United States. Electronic address: david.v.walsh.mil@mail.mil.
authors.forename: David V
authors.initials: DV
authors.lastname: Walsh
authors.affiliation: Department of Optometry, Womack Army Medical Center, 2817 Reilly Rd; Stop A, Fort Bragg, NC 28310, United States.
authors.forename: José E
authors.initials: JE
authors.lastname: Capó-Aponte
authors.affiliation: Department of Clinical Investigation, Womack Army Medical Center, 2817 Reilly Rd; Stop A, Fort Bragg, NC 28310, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Beltran
authors.affiliation: Department of Brain Injury Medicine/Defense and Veterans Brain Injury Center, Womack Army Medical Center, 2817 Reilly Rd; Stop A, Fort Bragg, NC 28310, United States.
authors.forename: Wesley R
authors.initials: WR
authors.lastname: Cole
authors.affiliation: Department of Optometry, Womack Army Medical Center, 2817 Reilly Rd; Stop A, Fort Bragg, NC 28310, United States.
authors.forename: Ashley
authors.initials: A
authors.lastname: Ballard
authors.affiliation: Department of Optometry, Womack Army Medical Center, 2817 Reilly Rd; Stop A, Fort Bragg, NC 28310, United States.
authors.forename: Joseph Y
authors.initials: JY
authors.lastname: Dumayas
mesh_terms: D000208:Acute Disease; D000328:Adult; D001924:Brain Concussion / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D053483:Eye Movement Measurements; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D008889:Military Personnel; D015203:Reproducibility of Results; D012438:Saccades; D014481:United States
keywords: King-Devick (KD) test; Mild traumatic brain injury (mTBI); Military; Saccades