Baseline Concussion Testing Often Reveals Invalid Result

March 30, 2018

DETROIT—A surprisingly large number of young athlete’s baseline concussion test scores do not accurately reflect their normal cognitive function, rendering the test invalid, a University of Windsor and Henry Ford Health System study reveals. The study appears in the March issue of JAMA Neurology.

Baseline testing is widely used to assess an athlete’s pre-concussion cognitive functioning. When an injury occurs, the test can help clinicians and athletic trainers determine when it is safe for an athlete to return to play by comparing post injury and baseline test scores.

For this study researchers compared four measures to detect invalid performance on baseline tests. Performance validity tests measure the test-taking behavior of athletes and whether or not the results accurately reflect the true “normal” cognitive abilities of the test taker.

“An invalid test is one where an individual’s low scores suggest there were issues affecting their performance and the test results do not reflect their actual abilities,” says Brad, Merker, Ph.D., a study co-author and co-director of the Henry Ford’s Sports Concussion Clinic

“We need to do a better job of ensuring that athletes do their best when they take a baseline test.”

The retrospective study included data collected between January 1, 2012, and December 31, 2016, from a clinical referral System in the Midwest. Participants included an equal number of 10 to 21-year-old male and female athletes who completed baseline neurocognitive testing for concussion management.

The baseline assessments were conducted using the Immediate Post-Concussion Assessment and Cognitive Test (ImPact), a computerized neurocognitive test designed for assessment of concussion. The test measures functions affected by concussion such as memory, reaction time, and visual motor speed.

The 30-minute test was conducted in groups of approximately 20 athletes and were overseen by athletic trainers or licensed clinical neuropsychologist at community centers, or in a hospital-based setting.

The study shows that base rates of failure (BRF), also known as the base rate of invalid performance, were surprisingly high.

Of the study’s 7,897 participants, 56 percent of athletes failed at least one of the four validity indicators. The base rate of failure varied considerably across age groups, from 29 percent in 21-year-old athletes to 84 percent in the 10-year-olds.

Among the youngest athletes, three out of four participants failed multiple validity indicators.

Based on study findings, researchers surmise that baseline testing usefulness may be questionable for 10 to 12-year-olds.

Over the past decade, computerized neurocognitive testing has largely replaced paper and pencil testing and has become widespread at all levels of sport. The ease of administering and scoring the test allows it to be given in a group setting and to be supervised by a wider range of health professionals.

“The expanded number of users and examiners supports the need to be more vigilant about monitoring the data the tests produce,” Merker added.

“It is important for examiners to be aware that how they administer the baseline tests has important implications for its value in later post-injury assessments.”

The study found that when taking baseline tests, younger children and adolescents were more likely to have invalid performance test results due to inattentiveness, poor understanding of the task or instructions or a lack of appreciation for the importance of doing their best on the test.

Besides age, performance might be affected by the testing environment. Also, larger groups yield more invalid baselines.

Researchers recommend:

• Making sure there are no distractions when giving the test to younger athletes and being certain that they understand the nature of the test and the instructions.
• Using all four validity algorithms to give practitioners a better sense of the validity of an athlete’s baseline test performance.
• Recognizing that failure of one validity indicator is cause for some concern, but failing two or more indicators are red flags suggesting invalid performance.
• Being mindful of the validity of baseline scores when using them to determine if an athlete has recovered from a concussion.

An estimated 1.5 million sport and recreation-related concussions occur annually in the United States in children aged 18 years or younger. The potential long-term effects of multiple concussions is leading to a focus on the management of concussion as a public health concern.


Synthia Bryant