SCAT 6 – 2023 Concussion Update

SCAT-6 UPDATE (with SCAT 5 comparison)

The 2022 International Consensus Statement on Concussion in Sport, which took place in Amsterdam, unveiled the most recent iteration of the concussion assessment tool known as Sport Concussion Assessment Tool-6 (SCAT-6) (1). This update was based on insights from 10 systematic reviews and an extensive consensus-building process involving a diverse set of stakeholders. All decisions were subject to a voting process, with a requirement for at least 80% agreement.

The SCAT-6 represents the most up-to-date version of the standardized concussion assessment tool, designed for use by healthcare professionals (HCPs) (2). The update features specialized versions catered to specific demographics, including the Child SCAT-6 designed for children under 13 years old, an in-office edition called the SCOAT-6, and the Concussion Recognition Tool 6 (CRT-6), intended for use by individuals without a healthcare professional background.

The SCAT-6 is designed for assessment of individuals within 72 hours following an incident, extending up to 7 days thereafter. Should the evaluation extend beyond this timeframe, it is recommended to use the SCOAT-6.

The key updates in SCAT-6, compared to SCAT-5 are outlined below. Screenshots from SCAT-5 are on the left, and SCAT-6 on the right for side-by-side comparison.

Front page:

The SCAT-6 front page incorporates multiple updates: patient details are moved to the second page, introduction of the term “healthcare professionals” to include a wider range of qualified individuals, and recommendation of a “10-15 minute” evaluation period, contrasting with the SCAT-5’s minimum of 10 minutes. It enhances the visual impact of verbal instruction with blue italics, cautions against the use of NSAIDs, sedatives, or opiates in concussion management, and emphasizes ongoing serial evaluations within hours and days, diverging from SCAT5’s recommendation to “consider” repeat assessments.

Second page:

This second introductory page is new to the SCAT-6 and offers an enhanced demographic section as well as a flow chart on how to use the SCAT-6. It streamlines the presentation of patient demographic information by centralizing it, eliminating the need for athlete name and information on each page. It also adds the concussion history with primary symptoms to this section.

IMMEDIATE OR ON FIELD ASSESSMENT:

This page continues to focus on triaging whether or not the patient should be removed from play for an off-field assessment. In the SCAT-6, a GCS <15 and visible deformity of the skull were added to the red flags section. In the observable signs section, falling unprotected to the surface, impact seizure, and high-risk mechanism of injury were added. The C-spine exam now includes assessing tenderness to palpation. The addition of the coordination and ocular/motor screen section is also new to the SCAT-6. This outlines the emerging evidence of the importance in identifying vestibulo-ocular deficits early on in concussion. The Maddocks questions are now in Step 5 of the SCAT-6 compared to Step 3 of the SCAT-5.

OFFICE OR OFF FIELD ASSESSMENT:

The SCAT-6 consolidates much of the athlete background information into the previously mentioned enhanced patient demographic section. The SCAT-6 also incorporates a notes section within the athlete background. In the symptom evaluation, a notable change is that instructions are now verbally communicated to the patient, whereas in the previous version, athletes were responsible for reading the instructions independently. Furthermore, a new addition to SCAT-6 is a dedicated box to record the time elapsed since the suspected injury. There is an additional note at the bottom for clinicians to consider revisiting positive symptoms to gather more detail.

COGNITIVE SCREENING:

SCAT-6 restructures the cognitive screen over multiple pages, with the most significant change being the shift to a mandatory 10-word list in the immediate memory subtest. This modification aims to address the “ceiling effect” observed in SCAT-5, where athletes achieved a mean score of 14.51 out of 15 on the immediate memory subtest when using the 5-word list (3). With that said, the SCAT-6 does not seem to define a standardized acceptable score, making it difficult to interpret the subtest without baseline testing. The SCAT-6 did however add a scoring system of 0 or 1 for each word, offering a more convenient method for tracking which specific words were recalled.

COGNITIVE SCREENING CONTINUED

In the concentration subtest of SCAT-6, additional guidance has been provided for administration, including clear parameters for test progression and when to conclude the subtest. Furthermore, SCAT-6 introduces a confirmatory example to ensure that the patient comprehends the instructions effectively. Regarding the “months in reverse order” test, SCAT-6 places emphasis on responding “as quickly and accurately as possible.” It is noted that a stopwatch should be used, and the test must be completed within 30 seconds to earn the point.

BALANCE EXAMINATION:

The next page of the SCAT-5 includes the neurological screen, which as mentioned previously, is now in Step 4 of the on-field assessment of the SCAT-6. The SCAT-5 neurological screen also includes tandem gait which is instead integrated in the balance screen of the SCAT-6.

The coordination and balance exam of the SCAT-6 has some significant changes, with the addition of a timed tandem gait component and an optional dual task gait. The timed tandem gait can be skipped if Modified Balance Error Scoring System (mBESS) is abnormal. There is also an added option to perform the mBESS on foam. Finally, there is the addition of an area to note if any of the trials were not completed due to walking errors or other reasons.

DELAYED RECALL:

The delayed recall section has also been updated in the SCAT-6 to include the 10 word list. The recall words are listed out in the SCAT-6 as well, making it easier for the examiner to record, instead of having to remember the words or reference back. Similar to the immediate recall, the SCAT-6 also added a scoring of 0 or 1 for each word. A total cognitive score was also added with the aim of improving the test–retest reliability and reducing false positives (1).

DECISION:

The decision page of both SCAT-5 and SCAT-6 contains largely similar information, with slight formatting differences. SCAT-6 introduces the addition of 10 points for delayed recall, as well as incorporating the fastest times for the timed tandem gait and dual task. The warning in red on the SCAT-6 is not as prominent as on the SCAT-5, instead adding a box for additional clinical notes. There is also an additional warning on SCAT-6 at the bottom: “Remember: an athlete can score within normal limits on the SCAT6 and still have a concussion”.

CONCUSSION INJURY ADVICE, INSTRUCTIONS, AND CONCUSSION INFORMATION:

The SCAT-5 has the entirety of the concussion information, return to play protocol, and test administration instructions. In the SCAT-6, these are now in the SCOAT-6.

High level summary of new features directly from the consensus statement (1):

Discussion

The SCAT-6 represents a significant progression in concussion assessment, introducing notable improvements aligned with the latest evidence in concussion research. There are considerable modifications to the design of the SCAT-6, enhancing the aesthetic, functionality, and ease of administration of the test. The emphasis placed on a 10-15 minute minimum assessment time is a positive step in exerting pressure on sporting bodies to allocate sufficient time to administer the tool. The SCAT-6 accentuates the importance of serial evaluations and stresses the necessity of removing athletes from play whenever there is suspicion of  concussion. This not only recognizes the variable and dynamic nature of concussion symptomatology, but emphasizes the importance of preventing further injury, especially when there can be pressure from athletes and coaches to immediately return to play. The new flowchart for on-field assessment stands out as a particularly useful illustration for practitioners. It is a clear and simple evaluation process that determines whether the player needs to be removed from play. The addition of coordination and oculomotor screening to the on-field assessment is also a positive step in highlighting the emerging evidence that oculomotor and coordination deficits are often seen in concussion. Intentional difficulty increases in subtests was a fundamental change in addressing the ceiling effect, and the addition of further optional tests provides practitioners with greater flexibility in administration. These changes will prove useful in potentially mitigating the false negatives in athletes who exhibit high baseline cognitive functioning. The cognitive screening section benefits from the addition of added instructions, integration of confirmatory examples, and instructions on when to utilize certain subtests, making administration easier for the HCP. Overall, there are many positive changes noticeable in the SCAT-6, both for the HCP administering, and the athlete.

While the SCAT-6 brings about many positive changes, there are also areas where further refinement could enhance its effectiveness. Although the SCAT-6 implements many different changes to mitigate the ceiling effect, it does not explicitly mention how to interpret different scoring measures. For example, it is not clear what are acceptable scores for the new 10 word recall and delayed recall, further highlighting the need for baseline testing of all athletes, which can often be difficult to implement. Further, it seems that the rationale for the changes was not always explicitly mentioned, such as why an arbitrary 30 seconds was chosen as the time to complete certain tasks. The extended length of SCAT-6, although ensuring comprehensiveness, may also introduce challenges in performing the assessment within a timely manner, especially if the HCP performs the optional tests. Finally, the absence of concussion information, return-to-play guidelines, and instructions in SCAT-6, though logically placed in SCOAT-6, could cause issues if the test administrator needed to reference how to administer a subtest. The cutout on concussion injury advice was also a valuable piece for the patient in the initial management of concussion.

Summary

The much anticipated SCAT-6 offers an important update in how HCPs diagnose and manage sport related concussion. There are significant positive changes to the update that will ultimately help with ease of administration, accurate assessment, and efficiency of the process; however, there are also some areas for further refinement. Overall, we hope to see the SCAT-6 used more often to aid in the diagnosis and management of concussion and ultimately improve patient outcomes and safety in sports.

Author:  Dr. John Vu, Dr. Alessandro Francella, Dr. Jim Niu (PR ND November 2023)

References

1. https://bjsm.bmj.com/content/57/11/695#T1
2. https://bjsm.bmj.com/content/57/11/622
3. https://bjsm.bmj.com/content/bjsports/early/2017/04/26/bjsports-2017-097506SCAT5.full.pdf
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6109942/