Values of the Sport Concussion Assessment Tool (SCAT3) in High School Athletes

Snedden TR, Brooks MA,
Hetzel S, McGuine T. Clinical Journal of
Sports Medicine
. 2016: Sep.

Home Message: Individual differences may be seen in baseline SCAT3 data between
sex, history of concussion, and history of comorbidities. Therefore, using the patient’s
personal medical history may add value to the SCAT3 sideline screening.

One of the most common
assessment tools utilized to screen for a concussion is the sport concussion
assessment tool (SCAT). Previous authors established that baseline testing
utilizing the SCAT2 version found scores varied depending on specific modifying
factors (age, sex, concussion history). The updated
was released; however, there has been little research done to establish if
these modifying factors exist in the current version. Therefore, the authors
evaluated baseline SCAT3 scores from 750 healthy, nonconcussed high school
athletes from 7 Wisconsin high schools (571 male; ~15 years of age) to establish normative data to account for sex, age and concussion
history differences. Athletic trainers administered the tool prior to the start
of each athlete’s respective season in a cafeteria or gymnasium. Two SCAT3
assessments (Maddocks questions and Tandem Gait) were not assessed as they were
either out of place in the baseline setting or participating athletic trainers
suggested they would not use this portion of the test during the sideline
assessment. The authors found that males reported higher baseline symptoms and
symptom severity scores compared to females, and females scored better on the
SAC and orientation scores than males. Additionally, athletes who self-reported
a history of concussions, headaches, migraines, learning disability, dyslexia,
attention deficit disorder/ attention deficit hyperactivity disorder (ADD/ADHD)
or depression/anxiety reported higher baseline symptoms and severity scores.
Athletes with a history of concussion did not perform differently on the SAC
portion of the SCAT3 compared to those without a history, but all of the other
previously mentioned modifiers showed worse performance. Athletes who
self-reported a history of concussion, diagnosis of a learning disability,
dyslexia or ADD/ADHD scored more errors on the balance error scoring system
(BESS) than those who did not. Age was not a modifying factor on any of the
SCAT3 sections.

This was an important
study because it was the first to evaluate the potential modifying factors for
SCAT3 baseline testing. Despite the presence of several statistically
significant findings, there were limited clinically significant findings
associated with each modifying factor and SCAT3 performance. An interesting
result of the current study was that athletes who self-reported a learning
disability scored worse on the BESS portion of the SCAT3. Similarly, the increased
symptom reporting by males (vs. females) does not align well with previously
reported sex differences. It should be noted that the SCAT3, like any test, has
limitations, which may limit certain uses in clinical practice. The SAC has
been observed to have ceiling effects, which can sometimes make interpretation
convoluted. In clinical practice, these limitations are sometimes mitigated by athletic
trainers modifying the way the SCAT3 is administered to make it more difficult.
Therefore, when a clinician is creating a normative database, it is important
to consider using those particular administration techniques, which are going
to be upheld during the post-injury assessment. It is not recommended and
caution is warranted when administering any test outside of the provided
instructions given that measurement properties such as reliability and validity
are based on those instructions. Individualized school/institution specific
normative data would not only limit variability in administration techniques,
but also decrease the uncertainty about how one institution’s athletes compare
to national normative values. As was seen in this study, differences are likely
to appear between subgroups such as sex and those with and without modifying
factors. Therefore clinicians should be aware of how their athlete population
performs and should use caution when utilizing normative data that was
collected outside of that population.

for Discussion: Do you use normative data or baseline data to evaluate your
athletes’ concussions? If so, whose normative data should you use?

Written by: Sam Walton, MEd, ATC

Reviewed by: Jane McDevitt

Related Posts:

Snedden TR, Brooks MA, Hetzel S, & McGuine T (2016). Normative Values of the Sport Concussion Assessment Tool 3 (SCAT3) in High School Athletes. Clinical journal of sport medicine PMID: 27606952