Spring 2015
Spring 2015

King-Devick Test
This January, the Mayo Clinic licensed the King-Devick Test, developed by 1976 alumni Alan King and Steven Devick while attending ICO. Measuring saccadic performance as it relates to reading ability, the test is used to detect concussions. Despite the fact that Mayo considers the K-D Test the gold standard for sideline concussion diagnosis, the test is still not widely used in the NFL. If given the opportunity to speak to NFL officials about concussion diagnosis, what would you say?

Danielle Leong, OD, FAAO

ICO Primary Care and Ocular Disease resident, 2012
Senior Director of Research, King-Devick Test

I’m not terribly concerned about millionaires playing for billionaires. But what happens on Sunday, happens on Friday.

At the highest level of play, the NFL is setting an example for millions of athletes from collegiate and high school down to USA Football and Pop Warner leagues.

The developing brains of children are at higher risk for injury and prolonged recovery. Their brains are not fully myelinated. Even at the age of five, their heads are already 90 percent of adult size, largely disproportional relative to their small necks –and then add on a few more pounds by throwing a helmet on them. John Madden put it into perspective when he said in a recent interview, ‘Why do we have to start with a six-year-old who was just potty trained a year ago and put a helmet on him and tackle?’

Athletes at the professional level represent only a small percentage of the total number of athletes playing football. The vast majority are at the high school and youth levels where the medical personnel afforded to professional athletes are limited, if not totally absent.

Professional athletes have access to countless physicians on the sideline as well as eyes in the sky specifically tasked with identifying possible head injuries. Even with all these safeguards in place, concussions still occur and players still continue to play with blatant head injuries. Case in point: During the 2015 Super Bowl, the New England Patriots’ Julian Edelman was so clearly concussed he was gripping his head, off-balance on several occasions, and during postgame interviews referred to Seattle as St. Louis. Apparently he had passed the NFL’s concussion test.

In most cases, team physicians use a test called the SCAT3, an eight-part physical and cognitive test conducted on the sidelines that takes about 15 minutes and requires a medically trained administrator. The Glasgow Coma Scale, which measures ocular, verbal, and motor response is included; however, opening your eyes spontaneously gets you a perfect score on the ocular portion of the test. Many players will score high despite having a concussion, which makes sense: The scale was developed as a tool to measure severe head trauma, so it isn’t even applicable to sports concussions, which are considered mild brain injuries. In other parts of the SCAT3, athletes are asked to repeat a string of numbers or words. They’re asked to answer simple questions like who scored the last touchdown, and put through a rudimentary coordination assessment similar to roadside DUI testing. Athletes close their eyes and touch their nose or stand heel to toe. Memory and balance represent just a small part of the brain leaving a lot of areas untested. Vision alone accounts for more than half of the brain’s pathways and eye movement function involves a wide neural network, yet there’s no real visual test on the SCAT3. An overall SCAT3 score is tallied up but there is no definitive “cut-off” score that determines whether a player should be removed from the game. The sideline physician makes a subjective decision based on an athlete’s performance on the test.

The King-Devick–a test of rapid number naming which requires visual processing, eye movements (accommodation, vergence, and saccades) as well as language and attention functions–is much more straightforward for an inexperienced physician or coach to grade than the SCAT3. Many concussed athletes have passed the SCAT3 exam but failed the King-Devick, and recent studies have shown the King-Devick not only has the highest capacity among sideline tests to distinguish concussed from non-concussed athletes, but that it is also tremendously additive to other sideline evaluation tools.

Optometry is distinctively suited to fill a vital role in concussion management by incorporating King-Devick concussion baselines into annual exams as well as patient and parent education on the utility of effective sideline tools to benefit athlete’s overall brain health.


Arol Augsburger, OD

ICO President

The King-Devick Test has been found to be a highly reliable, cost-effective, and time-efficient method to assess the likelihood of brain concussion on the sideline of sporting events. It is already being used as a sideline tool at the high school and college level to triage those likely to have a concussion, even those with no obvious symptoms.

It seems to me that the NFL would be well advised to utilize such a proven assessment technique that optometrists have been using for years. In contrast to other much more time intensive and costly assessments the NFL is currently using, the King-Devick Test would offer great value to the players and the NFL with high reliability.


Alicia Kinch ’16

President, ICO Sports Legacy Institute Community Educators chapter

The biggest drive for any athlete or sport is the win. Athletes are continuously asked to be at the top of their game both physically and mentally every moment to compete and reduce personal error for team success. When concussions go undetected, an athlete’s potential for error increases as their mental game is now faltered. Pristine athletes are being put at risk for sustaining an even worse mental game with repeated and unhealed concussions. As a result, an athlete may never return as the same player they were before.

The NFL pays for the best athletes to help their team win. With the King-Devick Test’s ability to rapidly detect concussions, it gives the NFL and its’ players the opportunity for earlier identification and a quicker onset for recovery. This should potentially allow each athlete to keep that pristine mental status–before repeated, unhealed concussions cause more serious injuries. In the long term, I see the NFL benefiting through the potential of the K-D Test to extend the length of their athletes’ careers. Even more importantly, as these athletes age, the NFL would be helping to preserve a healthy mental status for the individuals, long after their playing days are over.

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