Concussion Methodology

Question 1

1. Describe the Visual Analogue Scale (VAS), it’s origin, clinical application and internal and external validity and reliability.

Answer 1

• 1. Visual Analogue Scale (VAS):
• Origin: The Visual Analogue Scale (VAS) was first described by Freyd in 1923 as a method for measuring subjective phenomena. It was later adapted for use in clinical settings, particularly for assessing pain intensity.
• Clinical application: The VAS is widely used in clinical practice and research to measure various subjective experiences, such as pain, fatigue, anxiety, and mood.
• Internal validity and reliability: The VAS has demonstrated good internal consistency and test-retest reliability in various clinical populations. Its validity has been established through correlations with other pain and symptom assessment tools.

External validity and reliability: The VAS has been shown to have good external validity, as it correlates well with other measures of pain and subjective experiences across different clinical settings and populations. However, its reliability may be affected by factors such as the patient’s understanding of the scale, the precise wording of the instructions, and the time interval between measurements.

Question 2

2. The Visual Analogue Scale (VAS) has several limitations that should be considered when using it in clinical practice or research:

Answer 2

• The Visual Analogue Scale (VAS) has several limitations:
• 1. It relies on subjective perception, which can be influenced by psychological state, cultural background, and past experiences.
• 2. It may not be as precise as other measurement tools, and patients may have difficulty accurately pinpointing their experience on the scale.
• 3. Some patients may have difficulty understanding the concept of the VAS or interpret the scale differently, leading to inconsistencies in reporting.
• 4. There can be variability in an individual’s responses when the scale is administered at different times or by different healthcare providers.
• 5. The VAS may not be sensitive enough to detect small but clinically meaningful changes in the subjective experience, particularly at the lower or upper ends of the scale.
• 6. Contextual factors, such as the environment, the patient’s emotional state, or the presence of other symptoms, may influence responses on the scale.

Despite these limitations, the VAS remains a widely used tool for assessing subjective experiences. To minimize the impact of these limitations, it is essential to provide clear instructions, ensure patient understanding, and interpret results cautiously while considering the individual’s unique characteristics and the specific context in which the scale is used.

Question 3

The Borg Rating of Perceived Exertion (RPE) scale, while widely used and validated, has some limitations that should be considered:

Answer 3

• The Borg RPE scale has several limitations:
• 1. It relies on subjective perception, which can vary based on factors such as fitness level, experience, and psychological state.
• 2. It provides a general measure of exertion but does not differentiate between types of exertion.
• 3. RPE can be influenced by external factors, such as environmental conditions, medication use, or stress levels.
• 4. Some individuals may require time to accurately gauge their exertion levels, leading to initial inconsistencies.
• 5. There can be significant variability in RPE ratings between individuals performing the same task.
• 6. Individuals may intentionally or unintentionally misreport their RPE, leading to inaccurate assessments.
• 7. The scale may not be as precise in distinguishing between high levels of exertion.

Despite these limitations, the Borg RPE scale remains valuable for assessing perceived exertion when used with clear instructions and interpreted in the context of individual characteristics and the specific task being performed.

Question 4

Describe the Borg ratings of perceived exertion scale (RPE), it’s origin, clinical application and internal and external validity and reliability.

Answer 4

• 2. Borg Ratings of Perceived Exertion (RPE) Scale:
• Origin: The Borg RPE scale was developed by Swedish psychologist Gunnar Borg in the 1970s as a method for quantifying subjective perceptions of physical exertion during exercise.
• Clinical application: The Borg RPE scale is commonly used in exercise testing, prescription, and monitoring. It allows individuals to self-report their level of perceived exertion during physical activity on a scale from 6 to 20, with 6 representing no exertion and 20 representing maximal exertion. The scale is often used to guide exercise intensity and monitor progress in various clinical populations, such as those with cardiovascular diseases, pulmonary disorders, or chronic pain.
• Internal validity and reliability: The Borg RPE scale has shown good internal consistency and test-retest reliability in healthy individuals and clinical populations. Its validity has been established through correlations with physiological measures of exertion, such as heart rate and oxygen consumption.

External validity and reliability: The Borg RPE scale has demonstrated good external validity across different exercise modalities, intensities, and populations. However, its reliability may be influenced by factors such as the individual’s fitness level, previous experience with the scale, and psychological factors like motivation or mood.

Question 5

Why does the RPE scale start at 6 and end at 20?

Answer 5

• The Borg RPE scale ranges from 6 to 20, rather than starting at 0, to align with physiological measures of exertion, particularly heart rate.
• The scale was designed so that multiplying the RPE value by 10 provides an approximate corresponding heart rate. For instance, an RPE of 6 correlates with a heart rate of around 60 bpm (resting heart rate), while an RPE of 20 corresponds to about 200 bpm (maximal heart rate for many individuals).
  Moreover, starting the scale at 6 acknowledges the baseline level of exertion required for the body to perform basic functions, even at rest, thus eliminating the possibility of reporting zero exertion.

Question 6

Your study found that participants with sport-related concussions (SRC) demonstrated a baseline impairment in an oculomotor index of executive function (EF). Can you explain the significance of this finding and how it contributes to the existing literature on SRC and cognitive function?

Answer 6

• The finding of a baseline impairment in an oculomotor index of executive function (EF) in individuals with sport-related concussions (SRC) is significant because it highlights the subtle cognitive deficits that may persist even in the absence of overt symptoms.
• This result aligns with previous research demonstrating that SRCs can lead to impairments in various cognitive domains, including attention, executive function, and working memory (Howell et al., 2013; Rabinowitz & Levin, 2014; Sicard et al., 2018).
• By specifically focusing on an oculomotor measure of EF, this study provides a novel perspective on the cognitive challenges faced by individuals with SRC and contributes to the growing body of literature emphasizing the importance of comprehensive cognitive assessments in SRC management (Johnson et al., 2015; Webb et al., 2018).
  The findings suggest that oculomotor deficits in SRC may result from impaired EF planning rather than task-based symptom increases (Ayala et al., 2020), highlighting the need for targeted interventions to address these cognitive impairments.

Question 7

One of the key findings of your study is that a single bout of sub-symptom threshold aerobic exercise improved the oculomotor index of EF in individuals with SRC. Can you discuss the potential mechanisms underlying this improvement and the implications for SRC recovery?

Answer 7

• The improvement in the oculomotor index of EF following a single bout of sub-symptom threshold aerobic exercise suggests that exercise may have a beneficial effect on cognitive function in individuals with SRC.
• Exercise has been shown to increase cerebral blood flow (CBF) and promote neuroplasticity, which may support cognitive recovery (Leddy et al., 2019).
• Additionally, exercise may modulate neurotransmitter systems, such as dopamine and norepinephrine, which are involved in executive function (Dishman et al., 2006).
• The finding that the EF improvement was unrelated to the magnitude of exercise-mediated CBF increase suggests that other mechanisms may be more critical in driving this effect.
  These results have important implications for SRC recovery, as they suggest that sub-symptom threshold aerobic exercise may serve as a safe and effective intervention for promoting cognitive recovery, and that exercise prescription should be tailored to individual tolerance levels to optimize outcomes (Leddy et al., 2018; Leddy et al., 2019).

Question 8

Your study found that the improvement in EF following exercise occurred without a concomitant increase in SRC symptomology. Can you discuss the importance of this finding in the context of exercise as an intervention for SRC recovery?

Answer 8

• The finding that the improvement in EF occurred without a concomitant increase in SRC symptomology is crucial because it suggests that sub-symptom threshold aerobic exercise can be a safe intervention for individuals with SRC.
• One of the primary concerns in the management of SRC is the potential for symptom exacerbation with physical or cognitive exertion (Leddy et al., 2019).
• Our results demonstrate that when exercise intensity is carefully tailored to individual tolerance levels, it is possible to achieve cognitive benefits without worsening symptoms.
• This finding supports the growing body of literature advocating for the use of sub-symptom threshold exercise as a key component of SRC recovery protocols (Leddy et al., 2019; Schneider et al., 2020).
  By providing evidence that exercise can be both safe and effective in improving cognitive function, our study highlights the potential for exercise to play a central role in the management of SRC, both in the acute and subacute phases of recovery.

Question 9

9. Based on your findings, what are the potential implications for clinical practice and future research in the field of SRC management?

Answer 9

• The findings of our study have several important implications for clinical practice and future research in SRC management.
• First, our results underscore the importance of incorporating cognitive assessments, particularly those targeting executive function, into the evaluation and monitoring of individuals with SRC. By identifying subtle cognitive deficits, clinicians can better tailor interventions and track recovery progress.
• Second, our study provides evidence supporting the use of sub-symptom threshold aerobic exercise as a safe and effective intervention for promoting cognitive recovery following SRC. This finding highlights the need for clinicians to incorporate exercise prescription into their SRC management protocols, with a focus on individualized intensity levels and close monitoring of symptoms.
  Future research should aim to replicate and extend our findings, exploring the optimal timing, duration, and intensity of exercise interventions for SRC recovery. Additionally, studies investigating the long-term effects of exercise on cognitive function and symptom resolution in individuals with SRC are warranted. By continuing to investigate the role of exercise in SRC management, we can refine clinical guidelines and improve outcomes for individuals affected by these injuries.

Question 10

10. The number of participants completing the Buffalo Concussion Bike Test (BCBT) decreases after the 16-minute timepoint. What factors might have contributed to participants not completing the full 30-minute test, and how could this impact the interpretation of the results?

Answer 10

• Particpants did not complete the full 30-minute protocol mainly due to reaching voluntary exhaustion as defined by a Borg RPE rating of 17 or more points. The decreasing sample size after the 16-minute timepoint could potentially skew the group means and ranges for the Visual Analogue Scale (VAS) and Borg Rating of Perceived Exertion (RPE) scores.
• It is important to consider that the single (only one out of 16) participant who completed the full test also reported less severe symptoms and thus may have had better exercise tolerance compared to those who stopped earlier. This could lead to an underestimation of the average symptom severity and perceived exertion in the later stages of the test.
  To account for this, applying statistical methods that handle varying sample sizes would be valuable. Additionally, future studies might implement pacing strategies or rest intervals to allow more participants to complete the full duration, providing a more comprehensive dataset.

Question 11

The VAS and RPE scores show an increasing trend over the duration of the BCBT. How do these findings align with the current understanding of symptom provocation during exercise in individuals with sport-related concussions?

Answer 11

The increasing trend in VAS and RPE scores over the duration of the BCBT aligns with the current understanding that exercise can provoke symptoms in individuals with sport-related concussions. As the test progresses and the exercise intensity increases, participants are likely to experience a greater degree of symptom severity and perceived exertion. This finding supports the use of graded exercise testing, such as the BCBT, as a means to assess the relationship between exercise and symptom provocation in concussed individuals. The results also highlight the importance of monitoring symptoms during exercise and using this information to guide return-to-play decisions and the development of individualized exercise treatment plans.

Question 12

Given the findings presented in Table 2, what are the potential implications for the use of the BCBT in clinical settings, and what future research directions could help refine its application in concussion management?

Answer 12

• The findings in Table 2 support the use of the BCBT as a valuable tool for assessing the relationship between exercise and symptom provocation in individuals with sport-related concussions.
• The increasing trends in VAS and RPE scores demonstrate the test’s ability to elicit symptoms and gauge perceived exertion in a controlled setting. This information can help clinicians make more informed decisions about return-to-play readiness and guide the development of individualized exercise treatment plans.
• However, the decreasing sample size after the 16-minute timepoint highlights the need for further research to optimize the test duration and intensity to ensure that it is well-tolerated by a majority of concussed individuals.
• Future studies could also investigate the predictive validity of the BCBT in terms of long-term recovery outcomes and compare its performance to other exercise testing protocols.
• Additionally, research exploring the integration of the BCBT with other assessment tools, such as neurocognitive testing and balance measures, could help develop a more comprehensive approach to concussion management.
  By refining the application of the BCBT and understanding its strengths and limitations, clinicians can better utilize this tool to support the recovery of individuals with sport-related concussions.

Question 13

13. The VAS ranges remain relatively stable (0-4) throughout the test, while the RPE ranges show a steady increase (6-17). What insights can be drawn about the characteristics of your sample from the differences in these patterns, and how might they inform the use of these scales in concussion management?

Answer 13

• The stable VAS ranges (0-4) throughout the test suggest that the SRC participants did not experience a significant increase in symptom severity, even as the exercise intensity increased. In contrast, the steady increase in RPE ranges (6-17) indicates that the participants perceived the exercise as becoming more physically challenging over time. These patterns suggest that the SRC participants in my sample could tolerate increasing physical exertion without a corresponding increase in symptom severity.
• As VAS symptoms scores did not reach exacerbation threshold in any of the 16 participants, one could also argue that it is not a sensitive measure of concussion symptomatology, and that other similar scales that are brief and easy to administer during a graded exertion test, should be considered.
• Since the participants did not have symptom-limited exercise intolerance, they could potentially perform aerobic exercise at any HR up to the maximum achieved or at 85% of age-appropriate maximum, even if they are not yet cleared to return to play due to resting symptoms or physical examination impairments. This recommendation aligns with the BCBT instruction manual developed by Leddy & Haider.
• For the participant who completed the entire BCBT without significant exertion or symptom exacerbation, Leddy and colleagues’ recommendations suggest that additional evaluations should be considered for potential dysfunction.
• These evaluations may include:
• Cervical spine assessment: This may involve range of motion testing, palpation for tenderness, and manual therapy techniques to identify any cervical spine dysfunction that may be contributing to persistent symptoms such as headache or neck pain.
• Vestibular system assessment: This may include tests of vestibular function, such as the vestibular-ocular reflex (VOR), vestibular-spinal reflex (VSR), and sensory organization tests (SOT), to identify any vestibular dysfunction that may be contributing to symptoms such as dizziness or balance problems.
• Temporomandibular region assessment: This may involve palpation of the temporomandibular joint (TMJ) and surrounding muscles, as well as assessment of jaw range of motion and function, to identify any TMJ dysfunction that may be contributing to symptoms such as headache or jaw pain.
  These evaluations could help identify any underlying issues that may be contributing to the participant’s ongoing symptoms at rest, despite their ability to tolerate the full BCBT without symptom exacerbation.

Question 14

14. How can the findings of your study, which showed that none of the participants reached significant symptom exacerbation during the BCBT, be used to refine return-to-play protocols for individuals with sport-related concussions?

Answer 14

• The findings of my study suggest that a more individualized approach may be warranted. Since none of the participants reached significant symptom exacerbation during the BCBT, it may be possible to refine return-to-play protocols by:
• Incorporating the BCBT or similar graded exercise tests to assess exercise tolerance and identify participants who can safely engage in higher-intensity exercise without symptom exacerbation.
• Using the results of the BCBT to guide the prescription of individualized sub-symptom threshold aerobic exercise programs as part of the return-to-play process.
• Emphasizing the importance of monitoring both RPE and symptom severity during the return-to-play process, as RPE may be a more sensitive measure of exertion than symptom severity alone.
• As VAS symptoms scores did not reach exacerbation threshold in any of the 16 participants, one could also argue that it is not a sensitive measure of concussion symptomatology, and that other similar scales that are brief and easy to administer during a graded exertion test, should be considered.
  Ensuring that return-to-play protocols include evaluations for potential dysfunction of the cervical spine, vestibular system, or temporomandibular region, particularly for individuals who can tolerate high-intensity exercise without symptom exacerbation but continue to experience symptoms at rest.

Question 15

If Leddy and Haider’s BCBT manual suggested the following: “If the patient is able to exercise to voluntary exhaustion without any increase in symptoms (i.e. does not have symptom-limited exercise intolerance) but is not cleared to return-to-play because of symptoms at rest or physical examination impairments, then the patient can perform aerobic exercise at any HR up to the maximum achieved or at 85% of age appropriate maximum.” Why did you choose to perscribe them an aerobic exercise that was at 80% of their HRt?

Answer 15

• In this case, I chose to prescribe aerobic exercise at 80% of the patient’s heart rate threshold (HRt) instead of following the suggestion in Leddy and Haider’s Buffalo Concussion Bike Test (BCBT) manual for several reasons:
• The BCBT is a relatively new protocol compared to the well-established Buffalo Concussion Treadmill Test (BCTT). Although the BCBT has shown promise, it has only been examined in one study to date, which assessed its safety and reliability. Given the limited research on the BCBT, I opted for a more conservative approach to minimize the risk of symptom exacerbation.
• I wanted to maintain consistency in the exercise prescription by using the patient’s individual heart rate threshold (HRt) rather than relying on age-predicted maximum heart rate. Using the HRt ensures that the exercise intensity is tailored to the patient’s specific physiological response to exercise, as determined by the BCBT. This approach accounts for individual differences in fitness level and concussion recovery, providing a more personalized prescription.
  Given the possibility that the patient’s symptoms may have worsened between Visit 1 (BCBT) and Visit 2 (aerobic exercise prescription), I chose to err on the side of caution by prescribing exercise at 80% of HRt. This conservative approach aims to minimize the risk of symptom exacerbation while still providing a sufficient stimulus for recovery. By keeping the exercise intensity slightly lower than the maximum achieved during the BCBT, we can monitor the patient’s response and gradually progress the intensity as tolerated.

Question 16

Describe the scat-5’s internal and external validity and reliability

Answer 16

Internal Validity:

Internal validity refers to the extent to which the tool accurately and consistently measures what it is intended to measure.
The SCAT-5 has good internal validity as it assesses a range of concussion symptoms, cognitive functions, balance, and coordination, providing comprehensive information for healthcare professionals.
The components of the SCAT-5 are designed based on scientific research and expert consensus, ensuring that the tool evaluates relevant aspects of concussion assessment accurately.
External Validity:

External validity refers to the generalizability of the tool’s findings beyond the specific context or sample used in the assessment.
The SCAT-5 has good external validity as it is widely used in various sports settings and has been validated in different populations and age groups.
The tool’s standardized nature and established protocols enhance its external validity by allowing for comparisons across athletes and settings.
Reliability:

Reliability refers to the consistency and stability of the tool’s results over multiple administrations.
The SCAT-5 demonstrates good reliability, including test-retest reliability for baseline scores and inter-rater reliability among healthcare professionals administering the assessment.
Consistent administration of the SCAT-5 yields reliable results, making it a valuable tool for monitoring changes in athletes’ concussion symptoms and cognitive function over time.

Question 17

Why were the PARQ and GLETQ questionnaires important for the study design and validity?

Answer 17

• 1. PAR-Q:
• The PAR-Q is a self-administered questionnaire that helps identify individuals who may have health conditions or symptoms that could make physical activity unsafe for them.
• It asks about various medical conditions, symptoms, and risk factors that may be present and could potentially contraindicate or limit an individual’s ability to engage in physical activity.
• ” This questionnaire will tell you whether it is necessary for you to seek further advice from your doctor OR a qualified exercise professional before becoming more physically active. Please read the following seven (7) questions carefully and answer each one honestly”
• The purpose of administering the PAR-Q is to screen for any potential health concerns that may need to be addressed or investigated further before the individual undertakes the planned assessments or exercise protocol.
• Participants must obtain a full score to be eligible to be part of the study.
• 2. GLETQ:
• The GLETQ is a self-report questionnaire that assesses an individual’s level of physical activity and leisure-time exercise habits.
• It asks about the frequency and duration of various types of physical activity, such as strenuous, moderate, and light exercise.
• “During a typical 7-Day period (a week), how many times on the average do you do the following kinds of exercise for more than 15 minutes during your free time (write on each line the appropriate number). Weekly leisure activity score = (9 × Strenuous) + (5 × Moderate) + (3 × Light)”
• The SRC group was instructed to respond to this outside their concussion window i.e., a typical week as it would not have been representative of their normal activity level otherwise.
• The GLETQ was important in the context of this study for several reasons:
• It helps establish the baseline physical activity levels of the concussed athletes and healthy controls.
  Participants must obtain a score of 14 or more to be eligible.

Godin Scale Score Interpretation
24 units or more Active
14 – 23 units Moderately Active
Less than 14 units Insufficiently Active/Sedentary

Question 18

Why was the decision to not analyze the individual SCAT-5 cognitive clusters separately reasonable?

Answer 18

• Our decision to not analyze the individual SCAT-5 cognitive clusters separately is reasonable, as the SCAT-5 may lack the necessary sensitivity to detect subtle changes in specific cognitive domains following an SRC. This is confirmed by the lack of significant changes in SCAT-5 symptomology pre-and-post oculomotor task, despite a significant reduction in antisaccade RTs postexercise (i.e., a significant EF improvement).

Question 19

Why did you not analyze the VAS data and only provided the score means and ranges in a table?

Answer 19

• Low Variability:
• The VAS scores had a very narrow range, from 0 to 4 overall.
• This limited variability in the data points would have made it difficult to detect any meaningful statistical differences between conditions or time points.
• Incomplete Data:
• From minute 16 onwards, some participants reached voluntary exhaustion during the exercise protocol.
• As a result, not all participants provided VAS scores beyond that time point.
• The incomplete data set would have reduced the statistical power and validity of any inferential analyses performed.

Question 20

What do the similar RPE scores between the SRC and HC groups suggest about the exercise intervention?

Answer 20

• The comparable RPE scores throughout the exercise bout indicate that the SRC and HC participants experienced a similar subjective level of effort and physical strain during the sub-symptom threshold aerobic exercise.
  This suggests that the exercise intensity was appropriately tailored and tolerated by both groups, despite the potential cognitive and physiological impairments associated with the concussive injury in the SRC group.