The King-Devick Test objectively measures visual tracking and saccadic eye movements (rapid movement of the eye between fixation points). The test was originally developed in 1976 by eye care specialists to help evaluate reading disabilities as they related to oculomotor movement. Since 2011, the test has been used as a rapid sideline screening tool for concussion in a variety of sports, based on the findings that concussion is associated with many neuro-ophthalmologic signs. Many studies have shown the King-Devick Test to be a valid aid in detecting and evaluating concussions.