Nav: Home

Making it harder to 'outsmart' concussion tests

February 22, 2017

An equation that combines multiple subtest scores into one could make fooling a concussion protocol nothing more than a fool's errand, says a recent study from the University of Nebraska-Lincoln.

The study details a promising approach for pinpointing more athletes who play "impaired" on the Immediate Post-Concussion Assessment and Cognitive Testing, or ImPACT, a computerized tool consisting of eight subtests that gauge neurocognitive performance.

Administering ImPACT in the preseason helps establish a cognitive baseline that can be compared against the results of a post-concussion test, informing decisions about whether and when an athlete returns to action.

Concussions result from the brain slamming against the skull, usually causing short-term issues that some research suggests may evolve into long-term problems such as memory loss and depression when the brain is subjected to repeated trauma. To mitigate the risk of reinjury, athletes diagnosed with concussions take the ImPACT or a similar test to help determine when they have fully recovered.

But some athletes have undertaken the practice of sandbagging: giving lackadaisical effort on the baseline test to record a lower score in the hope of playing sooner after a concussion. Sandbagging can ruin the validity of the test and, because a recovering brain is more susceptible to further trauma, ultimately increase the likelihood of another concussion."At this point, people (administering) ImPACT may not have very much training in neuropsychological testing or standardized test administration or data interpretation," said lead author Kathryn Higgins, a postdoctoral researcher with the Center for Brain, Biology and Behavior at Nebraska. "If the baseline is the standard for when an athlete is recovered, there are all sorts of issues with returning someone to play based on poor baseline data."

So Higgins conducted an experiment to determine whether a statistical approach could identify more of the athletes who sandbagged on the baseline test. The experiment asked 54 athletes from rural Midwestern high schools to take the test twice, once while giving their best effort and once while subtly sandbagging. After analyzing the results, Higgins identified four subtests that created the largest disparity in scores. She then developed an equation that yielded a composite score from those subtests.

Establishing a threshold for the composite score allowed her to correctly find 100 percent of sandbagging cases while identifying the best-effort cases more than 90 percent of the time. Prior research suggests that ImPACT's existing system of validity checks, which flag suspicious scores on five individual subtests, detect just 65 to 70 percent of sandbaggers.

"Obviously, my flags are going to be better (in this case) because I built them and tested them on the same sample," said Higgins, who conducted the study as part of her dissertation. "But I thought it was worth pointing out that this equation has strong potential as another way to detect poor effort on baseline testing."

Higgins said she hopes further research will independently evaluate her approach and others that might improve the assessment of high school athletes, who suffer an estimated 300,000 sports-related concussions per year in the United States alone.

"There's so much room for work to be done," Higgins said. "We've come so far in the last 10 years -- we know so much more than we did -- but there are still a lot of things that we don't know."
Higgins authored the paper with Arthur Maerlender, director of clinical research at the Center for Brain, Biology and Behavior, and Robert Denney from Neuropsychological Associates of Southwest Missouri. It appeared in the journal Archives of Clinical Neuropsychology.

University of Nebraska-Lincoln

Related Concussion Articles:

Concussion protocols often not followed during FIFA World Cup
In the 2014 soccer World Cup, concussion assessment protocols were not followed in more than 60 percent of plays in which players involved in head collisions were not assessed by sideline health care personnel, according to a study published by JAMA.
Three ways neuroscience can advance the concussion debate
While concussion awareness has improved over the past decade, understanding the nuances of these sports injuries, their severity, symptoms, and treatment, is still a work in progress.
Concussion effects detailed on microscopic level
New research has uncovered details about subcellular-level changes in the brain after concussion that could one day lead to improved treatment.
Heads up tackling program decreases concussion rates, say researchers
Consistently using a tackling education program appears to help lessen youth football concussion severity and occurrence, say researchers presenting their work today at the American Orthopaedic Society for Sports Medicine's Specialty Day in San Diego, Calif.
Women may be at higher risk for sports-related concussion than men
Women athletes are 50 percent more likely than male athletes to have a sports-related concussion, according to a preliminary study released today that will be presented at the American Academy of Neurology's 69th Annual Meeting in Boston, April 22 to 28, 2017.
Making it harder to 'outsmart' concussion tests
Concussion testing on the athletic field depends upon comparing an athlete's post-concussion neurocognitive performance with the results of a previously administered baseline test.
Soccer players with more headers more likely to have concussion symptoms
Soccer players who head the ball a lot are three times more likely to have concussion symptoms than players who don't head the ball often, according to a new study published in the Feb.
Soccer ball heading may commonly cause concussion symptoms
Frequent soccer ball heading is a common and under recognized cause of concussion symptoms, according to a study of amateur players led by Albert Einstein College of Medicine researchers.
Could better eye training help reduce concussion in women's soccer?
With the ever-growing popularity of women's soccer, attention to sports-related concussions is also a growing concern.
Brain protein predicts recovery time following concussion
Elevated levels of the brain protein tau following concussion are associated with a longer recovery period and may serve as a marker to help physicians determine an athlete's readiness to return to play.

Related Concussion Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Failure can feel lonely and final. But can we learn from failure, even reframe it, to feel more like a temporary setback? This hour, TED speakers on changing a crushing defeat into a stepping stone. Guests include entrepreneur Leticia Gasca, psychology professor Alison Ledgerwood, astronomer Phil Plait, former professional athlete Charly Haversat, and UPS training manager Jon Bowers.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".