Study shows concussion assessments comprising of multiple tools is the best method to assess concussion
It is well known that assessment tools are required to identify concussion. Most organizations promote the use of multiple tools to evaluate several domains known to be impacted by concussion (1-4). Yet few studies have examined which tool individually or which tools in combination best assess and most accurately identify concussion. A recent study — which examined 22,057 player seasons collected during 2014-2017 for multiple sports from various NCAA and military schools — has found that concussion assessments comprising of multiple tools, including a subjective symptom tool, is the best method to assess concussion.
One Assessment Tool to Rule Them All?
In the study, all “full models” — meaning concussion assessments comprised of multiple tools — outperformed all individual tools
Unfortunately, no singular tool that assesses concussion is more effective than a combination of tools. In the study, all “full models” — meaning concussion assessments comprised of multiple tools — outperformed all individual tools, suggesting that testing batteries are more effective at identifying the effects of concussion (5-9). Interestingly, removing the SCAT total symptoms from the full model resulted in the greatest reduction in a model’s performance. On the other hand, removing the BESS minimally impacted the model’s performance, highlighting the BESS assessment’s possible lack of utility in assessing concussion. Ultimately, these results suggest that symptoms better indicate concussion than neurological status and balance assessments. These results differ from other studies that suggest neurological assessment has the highest sensitivity, but this difference may be attributed to methodology and sample size (5,6,8-10).
Are Baseline Tests Necessary or Useful?
Completing baseline testing is becoming more common, but the presumed problem arises when the baseline data is not available to the medical professional assessing the concussed individual.
Some assessment tools use baseline tests to examine the difference between an athlete’s performance before and after the concussive injury. Completing baseline testing is becoming more common, but the presumed problem arises when the baseline data is not available to the medical professional assessing the concussed individual. Even when the data is available, the usefulness of this data remains questionable (11-13). The study found that while there is utility in baseline test scores for the SAC and SCAT (but not the BESS), it is still possible to adequately assess concussion without baseline tests and therefore baseline results may not be clinically valuable (7,10,12,13). In saying that, since this study examined only the assessment of acute concussion, it is possible that baseline information may be useful beyond this acute stage but research is needed to explore this train of thought.
Subjective vs. Objective Data
The underreporting of symptoms (at a rate as high as 50%) may greatly impact how effective concussion assessments are
Since the study showed that symptom scores have a higher sensitivity and specificity than objective measures, the underreporting of symptoms (at a rate as high as 50%) may greatly impact how effective concussion assessments are — many concussions could go unidentified (14). Unfortunately, all objective assessment tools were outperformed. This raises the importance for developing better objective means in which to diagnose concussion. In saying that, it is possible that the objective tools play an important role once symptoms resolve; examining the utility of objective assessment tools beyond the acute stage is important.
Potential Areas of Improvement
The simultaneous use and interpretation of multiple tools with multiple domains is challenging especially when it does not have a method to combine the results into a single measure
The findings of this study provide some direction as to how to improve concussion assessments. For instance, since the BESS does not provide much value, it may be worth considering removing the tool from assessments; removing the tool would also reduce the time it takes to assess concussion. Furthermore, since this study combined risk modifiers and standard assessments into one score which can be gathered within the time constraints of most sports, there is potential for this to be applied to sideline concussion assessment/management. Indeed, the simultaneous use and interpretation of multiple tools with multiple domains is challenging especially when it does not have a method to combine the results into a single measure (1,3,4,15).
Finally, while the study did not find significant relationships in terms of age, sex, or previous numbers of concussion, it still may be important to incorporate modifying factors (the ones mentioned above as well as numerous others not examined in this study) into acute concussion assessments. Indeed, they can be important factors to consider. For instance, this study found that males were found to have an increased risk of acute concussion (25, 51-53). At first, it looks like this result is contradictory to many other studies that have found females experience more symptoms and a worse cognitive decline (24,26,50,53,54). However, this study’s finding seems to suggest that male athletes may still be concussed despite having fewer symptoms and closer-to-normal neurocognitive deficits compared with female athletes. This fact/trend would be worth knowing and considering when assessing concussion and should be built into the assessment.
Areas to Explore
While this study did find concrete ways in which to improve concussion assessment, it also highlighted areas that are certainly lacking in information and require more research.
- First, similar research is needed for high school, recreational, and professional athletes to examine whether these findings are similar across all categories of athletes.
- Second, this study has limitations in the fact that it only looked at specific concussion assessments — examining both individual components of each assessment, as well as other assessments, will be important.
- Third, as mentioned above, research on the usefulness of these tools, baseline scores, and objective data beyond the acute stage is required.
Finally, this study does highlight the need for research on other clinical measures that can be used when certain objective data is either unavailable or not as clinically valuable and self-reported symptoms are unreliable.
The study can be found here: https://www.ncbi.nlm.nih.gov/pubmed/29488165
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