Dhiren Naidu

A qualitative review of sports concussion education: prime time for evidence-based knowledge translation

Background Educating athletes, coaches, parents and healthcare providers about concussion management is a public health priority. There is an abundance of information on sports concussions supported by position statements from governing sport and medical organisations. Yet surveys of athletes, parents, coaches and healthcare providers continue to identify multiple barriers to the successful management of sports concussion. To date, efforts to provide education using empirically sound methodologies are lacking. Purpose To provide a comprehensive review of scientific research on concussion education efforts and make recommendations for enhancing these efforts. Study design Qualitative literature review of sports concussion education. Methods Databases including PubMed, Sport Discus and MEDLINE were searched using standardised terms, alone and in combination, including ‘concussion’, ‘sport’, ‘knowledge’, ‘education’ and ‘outcome’. Results Studies measuring the success of education interventions suggest that simply presenting available information may help to increase knowledge about concussions, but it does not produce long-term changes in behaviour among athletes. Currently, no empirical reviews have evaluated the success of commercially available sports concussion applications. The most successful education efforts have taken steps to ensure materials are user-friendly, interactive, utilise more than one modality to present information and are embedded in mandated training programmes or support legislation. Psychosocial theory-driven methods used to understand and improve ‘buy in’ from intended audiences have shown promise in changing behaviour. Conclusions More deliberate and methodologically sound steps must be taken to optimise education and knowledge translation efforts in sports concussion.

Assessment of symptoms in a concussion management programme: Method influences outcome

Context: Monitoring of subjective symptoms is the foundation of all sport concussion management programmes. The purpose of this study is to examine methodological variables that impact symptom reporting during baseline testing. Objective: To investigate how the administration method of a concussion assessment tool (self-report vs interview) affects the report of symptoms. Design, setting and participants: This was a cross-sectional, semi-randomized study of 117 athletes. Main outcome measurements: Subjects completed the Post-Concussion Scale during pre-season evaluations. Results: A two-factor ANOVA revealed a significant difference in total symptom scores (p = 0.02) and number of endorsed symptoms (p = 0.02) across administration modes. Athletes had a greater total symptom score and reported a greater number of symptoms in the self-administration condition than in the interview condition. Furthermore, there was a significant difference in symptom reporting across interviewer gender. Athletes endorsed more symptoms when the interviewer was a woman. Conclusions: Because the method of collecting symptoms, as well as interviewer gender, can impact test results, self-report measures may be a better way of obtaining consistent results. Clinicians and researchers should be aware that both the nature and extent of symptom reporting is greater when using questionnaires than when athletes are interviewed.

Does an individual's fitness level affect baseline concussion symptoms?

CONTEXT Variables that may influence baseline concussion symptoms should be investigated. OBJECTIVE To evaluate the effect of physical fitness on self-report of baseline concussion symptoms in collegiate athletes and students. DESIGN Controlled laboratory study. PATIENTS OR OTHER PARTICIPANTS A total of 125 undergraduates, including 95 collegiate athletes and 30 recreational athletes (83 males, 42 females). INTERVENTION(S) Participants completed the Standardized Concussion Assessment Tool 2 (SCAT2; symptom report) at baseline, within 10 minutes of completing the Leger test, and within 24 hours of the initial baseline test. The Leger (beep) test is a shuttle-run field test used to predict maximal aerobic power. MAIN OUTCOME MEASURE(S) The total symptom score on the SCAT2 was calculated and analyzed with a repeated-measures analysis of variance. A linear regression analysis was used to determine if 3 variables (sport type, sex, or fitness level) accounted for a significant amount of the variance in the baseline symptom report. RESULTS Participants reported more symptoms postactivity but fewer symptoms at 24 hours compared with baseline, representing a time effect in our model (F2,234 = 47.738, P < .001). No interactions were seen among the independent variables. We also found an effect for fitness level, with fitter individuals reporting fewer symptoms at all 3 time intervals. The regression analysis revealed that fitness level accounted for a significant amount of the variance in SCAT2 symptoms at baseline (R (2) = 0.22, F3,121 = 11.44, P < .01). CONCLUSIONS Fitness level affected the baseline concussion symptom report. Exercise seems to induce concussion symptom reporting, and symptom severity may be a function of an athletes level of conditioning. Sports medicine professionals should consider an athletes level of fitness when conducting baseline concussion symptom assessments.

Sideline Concussion Assessment: The King-Devick Test in Canadian Professional Football

Sideline assessment tools are an important component of concussion evaluations. To date, there has been little data evaluating the clinical utility of these tests in professional football. The purpose of this study was to evaluate the clinical utility of the King-Devick (K-D) test in evaluating concussions in professional football players. Baseline data was collected over two consecutive seasons in the Canadian Football League as part of a comprehensive medical baseline evaluation. A pilot study with the K-D test began in 2015 with 306 participants and the next year (2016) there were 917 participants. In addition, a sample of 64 participants completed testing after physical exertion (practice or game). Participants with concussion demonstrated significantly higher (slower) results compared with baseline and the exercise group (F[2,211] = 5.94; p = 0.003). The data revealed a specificity of 84% and sensitivity of 62% for our sample. Reliability from season to season was good (intraclass correlation coefficient [ICC] 2,1 = 0.88; 95% confidence interval [CI]: 0.83, 0.91). On average, participants improved performances by a mean of 1.9 sec (range, -26.6 to 23.8) in subsequent years. High reliability was attained in the exercise group. (ICC2,1 = 0.93; 95% CI: 0.89, 0.96). The K-D test presents as a reliable measure although sensitivity and specificity data from our sample indicate it should be used in conjunction with other measures for diagnosing concussion. Further research is required to identify stability of results over multiple usages.

Does Game Participation Impact Cognition and Symptoms in Elite Football Players

Objective:To measure neurocognitive functioning in college and professional football players after game participation. Study Design:Retrospective, cross-sectional cohort design. Participants:Ninety-four male university and professional football players. Intervention:All participants completed Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) testing at baseline, and either at postconcussion (group 1) or postgame (group 2) participation. Main Outcome Measures:Results from the 5 ImPACT composite scores (Verbal Memory, Visual Memory, Visual Motor Speed, Reaction Time and Impulse Control) and Total Symptom Score. Results:Repeated-measures analysis of variance demonstrated a significant main effect for time (improvements) in 3 of 5 domains for the postconcussion group, but no improvements in the postgame group. The postconcussion group presented with significantly improved results on 4 of 5 ImPACT domains compared with the postgame group at the follow-up time interval. Conclusions:Participation in a football game with potential cumulative head contacts did not yield increased symptoms or cognitive impairment. However, the absence of improvement in cognitive functioning in noninjured football players, which was found in those players who were returned to play after an injury, may suggest that there is a measureable impact as a result of playing football.

Reliability of the scat2/3 in college athletes

Objective To evaluate psychometric properties of the Sport Concussion Assessment Tool (SCAT). Design Retrospective clinical study in which athletes completed the SCAT over 2 consecutive seasons. Athletic therapists administered the SCAT and a pre-season medical questionnaire. Setting University setting. Participants 165 college athletes who were enrolled at a university in Western Canada who played collision sports. Intervention the SCAT2 and subsequently the SCAT3 was administered to all participants at baseline. Main outcome measures Intraclass coefficients (ICC’s) and paired sample t-tests. Main results The intraclass reliability coefficients for demographic variables ranged from moderate to good (0.66 to 0.94). The reliability of the cognitive test results and balance error scoring system (BESS) was rated as good (0.83 and 0.88 respectively). Total symptom report and symptom severity report was moderate, with significant differences noted between males and females. History of concussion did not significantly impact reliability coefficients. Among the 22 athletes who suffered concussions during a competitive season, the reliability of the core components of the SCAT remained high. Conclusions The reliability of the SCAT2/3 is classified as good although symptom report is more variable Competing interests None. Keywords: concussion, sport concussion assessment tool, psychometric properties

Concussion diagnosis: the king-devick test in the canadian football league

Objective To conduct a sensitivity analysis of the King-Devick (K-D) test in professional football. Design Prospective cohort. Setting Professional football. Participants: 269 professional football players from the Canadian Football League (CFL). There were 24 concussions to analyse. Intervention The K-D test was added to the existing CFL concussion protocol (medical and SCAT3). All participants completed K-D assessments at baseline, at the time of injury/concussion (TOI), and at medical clearance prior to return to play (RTP). 20 controls were re-tested post-baseline. Outcome measures K-D scores were analysed to construct a sensitivity analysis. Main results TOI K-D results were significantly higher (mean=50.21, range: 35.4–107.4) than baseline K-D results (mean=44.3, range 28.4–66.4; p<0.01). TOI K-D results yielded 94% sensitivity and 80% specificity for diagnosing concussions. Four groups emerged from the TOI data. In Group 1, 4/4 were asymptomatic within 24 hours and scores were better (lower) than baseline; Group 2 were asymptomatic within 72 hours and 8/9 had abnormal (poorer) scores; Group 3 were asymptomatic within 11 days and 5/5 had abnormal scores. Group 4 were symptomatic by season’s end and 4/4 had abnormal scores. 18/18 players who RTP had better K-D scores than baseline prior to RTP. Conclusions The K-D test proved to be useful for concussion diagnosis. Interestingly, the players in Group 1 had normal TOI K-D scores and were asymptomatic in <24 hours. More research is needed and the CFL will continue this next season. Competing interests None.

Classifying invalid baseline scores

Objective Analysis of a proposed method for classifying invalid baseline tests in professional football players. Design Retrospective cross-sectional study. Setting Professional Canadian Football. Participants Four hundred and seventy-eight male football players from the Canadian Football League. Intervention A proposed system to classify invalid baselines used the lowest 5% of domain scores from baseline Immediate Post-concussion Assessment and Cognitive Testing (ImPACT), King Devick, and SCAT3 (balance and SAC totals) coupled with the highest 5% of total symptom report from SCAT3. Impairment on 2 or more scores was classified as invalid (INV). Main Outcome measures Descriptive statistics, correlation and stepwise regression analysis. Main Results Correlations revealed significant relationships (p<0.05) between INV and all 5 domains of ImPACT and SCAT3 symptom score, but not for King Devick and SCAT3 balance and SAC totals. The forward stepwise regression yielded a significant model (R2=0.23, F(4, 473)=35.7, p<0.001). Significant predictors included visual memory, reaction time, impulse control, and verbal memory from ImPACT. This system classified 3.7% of participant with invalid baseline tests. Conclusions There are few published methodologies used to classify invalid baseline tests in spite of their widespread use. Valid baseline tests are essential for proper identification and management of concussion. Our proposed method identified 4 ImPACT domains scores that predict invalid baseline scores. This system may be helpful in classifying invalid baseline tests with commonly used baseline test measures although more research is required to validate this method. Competing interests None.

The impact of fitness level on self-report of concussion symptoms

Background The diagnosis and management of concussion in sport rely heavily on self-report of symptoms by the athlete. However, many symptoms commonly reported after a concussion (headache, nausea, fatigue, etc.) may be influenced by other factors. Fatigue is a frequent complaint, but may actually be a function of level of physical fitness. Objective To evaluate the role of physical fitness on self-report of concussion symptoms in collegiate athletes and students, during baseline testing. Design Prospective repeated measures. Participants 125 subjects were recruited, including 95 collegiate athletes and 30 undergraduate students (83 males and 42 females). Athletes were screened for medical and psychological conditions. No athlete had a recent history of concussion. Intervention Subjects completed the Standardised Concussion Assessment Tool (SCAT1) at three time periods: prior to a Leger (Beep) test, within 10 min of test completion, and within 24 h. The Leger test has established validity and reliability to estimate an athletes V02 maximum and overall fitness levels. Main outcome measures Estimated V02 max (Leger test) and symptom scores on the SCAT1. Results Subjects were grouped into three levels of fitness according to criteria established by the American College of Sports Medicine (2010). A 3×3 repeated-measures ANOVA was not significant for the overall model but showed a significant interaction between time and fitness level (F (2, 121)=3.50, p=0.02). Post-hoc analysis revealed significant differences in report of symptoms among the three fitness groups at baseline and immediately post-activity, but not at 24 h. Conclusion Results provide evidence of a moderating effect of fitness level on report of concussion symptoms at baseline, even in healthy adults. Specifically, exercise can induce symptom reporting, and may a function of an athletes level of conditioning. Sport medicine professionals making decisions following concussion need to consider an athletes level of fitness when evaluating post-concussion symptoms.