An innovative approach to measuring youth concussion recovery: Occupational performance

Abstract

Introduction

Concussion is a common injury in youth. Studies report that active rehabilitation interventions reduce symptoms in these youth. There is no literature that addresses its impact on occupational performance. The purpose of this study was to identify: (a) occupational performance issues experienced by these youth; (b) changes in occupational performance and satisfaction following participation in a 6-week active rehabilitation intervention; and (c) the relationship between changes in occupational performance and symptoms.

Method

As part of a larger prospective repeated measures study, measures of occupational performance (Canadian Occupational Performance Measure) and self-reported symptoms (Post-Concussion Symptom Inventory) were collected pre and post intervention. Paired t-test, Spearman correlation, and descriptive analyses were conducted.

Results

Youth (9–18 years; n = 52) reported a range of occupational performance issues in self-care, productivity, and leisure domains. The most frequently reported occupational performance issues were sport (32.70%) and school (31.75%) activities. Positive changes were found in both performance and satisfaction of occupational performance issues post intervention (p<.001). Correlation analysis revealed that as symptoms decreased, occupational performance improved (r_s = –.359, p = .020).

Conclusion

Using a measure of occupational performance may provide meaningful insight into the functional recovery of concussion, and can help identify targeted functional approaches to paediatric concussion management.

Keywords

Paediatric youth concussion recovery occupational performance occupational therapy

Introduction

Concussion, also known as a mild traumatic brain injury (mTBI), can result in physical, cognitive, emotional, and/or sleep-related symptoms (Reed et al., 2015). Concussions are considered to be a significant public health concern due to the acute and long-term consequences for children and youth (Daneshvar et al., 2011). Symptoms of concussion commonly reported by children include sleep disturbance, as well as physical (for example headache and fatigue), cognitive (for example inattention and memory deficits), and behavioural (for example irritability, anger, and depression) symptoms (McCrory et al., 2017; Reed et al., 2015). Symptoms typically resolve within 10–14 days in adults, and 4 weeks in youth (McCrory et al., 2017). However, a subset of youth experience symptoms that persist weeks to years after their injury (Barlow et al., 2010; Zemek et al., 2016).

Clinical recovery from concussion is most frequently measured using symptom outcomes identified by self-report symptom scales (Iverson et al., 2017). According to the Dove-Hawk Model of Allostatic Load for Youth with Persistent Concussion Symptoms, some youth with persistent symptoms may experience heightened fear due to the recurrent focus on symptoms (Paniccia and Reed, 2017). Prolonged states of fear may result in avoidance of activity, and secondary health issues such as anxiety and physical deconditioning (Maller et al., 2010; Thomas et al., 2015). Recurrent use of self-report symptom measures may not be helpful to a youth’s recovery, and an alternative measure of concussion recovery may be needed.

A youth’s capacity for performance of, and engagement in, meaningful activities post concussion is restricted by symptoms, and a medically recommended period of cognitive and physical rest followed by gradual resumption of activity (McCrory et al., 2017; Ontario Neurotrauma Foundation, 2013). Children recovering from brain injury may be challenged by an impairment of previously acquired skills, and/or an impaired ability to obtain new age-expected skills (Dykeman, 2003). Despite changes to these youth’s ability to perform daily activities, there is little literature on specific self-identified occupational performance issues (OPIs) by youth post concussion, nor interventions that influence positive change in these OPIs.

Emerging literature suggests that early participation in physical activity can decrease symptom severity and duration in children and youth with persistent symptoms (Grool et al., 2016). Exercise promotes recovery of cognitive function after traumatic brain injury, positively affecting mental health, self-esteem, memory, sleep patterns, and overall wellbeing in children (Griesbach et al., 2004). Active rehabilitation interventions commonly consist of aerobic exercise, alongside coordination drills, visualization, and education. Several studies on active rehabilitation interventions for youth with persistent symptoms have found improvement in symptoms following intervention (see for example Dobney et al., 2017; Gagnon et al., 2009, 2015; Imhoff et al., 2016; Kurowski et al., 2017; Lawrence et al., 2018).

Despite positive findings, the majority of the discussed paediatric active rehabilitation studies were limited to examination of small sample sizes of sport-related concussions. While previous studies measured recovery by changes in self-reported symptoms, to our knowledge, no studies to date have measured change in occupational performance. In addition, little is known about the relationship between changes in OPIs and post-concussion symptoms following participation in active rehabilitation programmes. Understanding the changes in occupational performance post active rehabilitation may offer an alternative method of measuring concussion recovery, and would contribute toward a client-centred functional approach to concussion assessment in youth.

Therefore, this study aims to: (a) describe specific OPIs identified by youth post concussion; (b) identify how performance and satisfaction ratings of self-reported OPIs change after completion of a 6-week active rehabilitation intervention; and (c) explore the relationship between changes in ratings of self-reported OPIs and severity of concussion symptoms.

Method

Design

This is a sub-study of a larger prospective repeated measures design (Reed et al., 2015). The larger study uses a 6-week active rehabilitation intervention for youth ages 9 to 18 years who are at least 2 weeks post concussion. The study was conducted at a paediatric rehabilitation hospital in a large urban setting. Ethical approval was granted by the Holland Bloorview Kids Rehabilitation Hospital Research Ethics Board and the University of Toronto Research Ethics Board in 2016.

The active rehabilitation intervention was based on the programme developed by Gagnon et al. (2009) and consisted of comprehensive education, graded low-intensity aerobic exercises (such as walking or stationary bike), sport-specific coordination drills, and relaxation exercises (for example visualization). Following initial assessment, youth were instructed to complete the programme daily at home, and were monitored through weekly scheduled telephone check-ins, and during an in-person reassessment at week three (Reed et al., 2015). Comprehensive education included information about concussion definition and diagnosis, energy conservation, sleep hygiene, relaxation strategies, nutrition, hydration, self-management strategies, and return to activity and school guidelines (Hunt et al., 2016).

Participants, recruitment, and eligibility

Participants for the larger study were recruited from the facility’s concussion clinic, local community practitioners (including family physicians and paediatricians), sports organizations, and the local community. Written informed consent was obtained from all participants and their parents.

Inclusion criteria were: (a) confirmed diagnosis of concussion by a physician; (b) aged 9 to 18 years; (c) presence of at least one post-concussion symptom for more than 2 weeks as identified by the Post-Concussion Symptom Inventory; (d) fluency in written and spoken English; and (e) capacity to provide consent for participation. Participants were excluded from the study if they: (a) were experiencing neck pain; (b) scored 7/10 or higher on a visual analogue scale of wellness (0 = feeling very well and 10 = feeling very unwell); (c) had significant balance dysfunction or other pre-existing comorbidities that prevented them from walking safely or using a stationary bicycle; or (d) were unable to follow directions (Reed et al., 2015).

In addition to the above, eligibility for the current sub-study included those participants who completed the 6-week intervention and had completed measures of occupational performance (Canadian Occupational Performance Measure (COPM)) and symptoms (Post-Concussion Symptom Inventory (PCSI)) both pre and post intervention.

Primary outcome measures

Primary outcome measures (COPM and PCSI) were administered in person by trained occupational therapy and/or physiotherapy students at intake (week zero) and immediately following completion of the 6-week active rehabilitation intervention (week six).

Canadian Occupational Performance Measure

The COPM is a standardized, client-centred measure used to detect change in self-perceived performance and satisfaction of OPIs over time (Law et al., 1998). The OPIs are self-reported in the areas of self-care, productivity, and/or leisure. A semi-structured interview is used to facilitate participants’ identification of a minimum of five OPIs. The five most important OPIs to the participant are determined using a 10-point rating scale (1 = not important at all and 10 = extremely important). OPIs are then rated by the participant according to their own level of performance and satisfaction with performance, using a 10-point rating scale (performance rating of 1 = not able to do it and 10 = able to do it extremely well; satisfaction rating of 1 = not at all satisfied and 10 = extremely satisfied) (Law et al., 1998). A two-point change is considered to demonstrate clinical significance (McColl et al., 2006). The COPM has been shown to be reliable, valid, clinically useful, and responsive to change with adults and children in rehabilitation settings (Carswell et al., 2004).

Post-Concussion Symptom Inventory

The PCSI is designed to measure the presence of physical, cognitive, emotional, and fatigue symptoms associated with concussion (Sady et al., 2014). The PCSI was developed for self-report, teacher report, or parent report (Sady et al., 2014). The PCSI includes different assessment versions for different developmental age groups. For this study, two self-report versions were used: (a) PCSI-SR8 for youth aged 8 to 12, and (b) PCSI-SR13 for youth aged 13 to 18. The vocabulary and response format in each form is developmentally specific for the respective age groups (Sady et al., 2014). PCSI-SR8 contains 17 items with simplified wording of symptoms (for example, ‘Have you felt more tired than usual?’), and the response is graded on a three-point Guttman scale ranging from zero to two (0 = no, 1 = a little, 2 = a lot) (Sady et al., 2014). The PCSI-SR13 contains 21 items such as ‘fatigue’ and ‘dizziness’. Responses are rated for severity using a seven-point Guttman dimensional scale ranging from zero to six (0 = not a problem, 3 = moderate problem, 6 = severe problem) (Sady et al., 2014).

Moderate to high internal consistency has been demonstrated by both PCSI-SR8 (alpha = 0.62–0.84 for subscales, alpha = 0.90 for total symptom score) and PCSI-SR13 (alpha = 0.79–0.93 for subscales, alpha = 0.94 for total symptom score) (Sady et al., 2014). High test–retest reliability of the PCSI-SR8 (ICC = 0.89) and PCSI-SR13 (ICC = 0.79) has also been demonstrated (Sady et al., 2014).

Secondary outcome measures

Secondary outcome measures included the Acute Concussion Evaluation (ACE), and a demographics data collection form developed specifically for this study. Measures were administered by clinically trained occupational therapy and/or physiotherapy students at intake (week zero) of the active rehabilitation intervention.

Acute concussion evaluation

The ACE is a standardized measure used in the initial evaluation of children or adults with known or suspected mTBI in primary care settings (Gioia et al., 2008). The measure inquires about specific characteristics of the injury, including mechanism of injury, five signs and 22 symptoms associated with mTBI, and risk factors that may predict prolonged recovery. The ACE exhibits strong psychometric properties, such as good internal consistency, construct validity, predictive validity, and convergent and divergent validity (Gioia et al., 2008).

Demographics form

The demographics form inquires about the participant’s age, sex, weight, height, pre-injury activities (for example sport participation), pre-injury self-reported academic performance, concussion history, and pre-injury diagnoses.

Data analyses

The demographics, ACE, COPM, and PCSI data collected from a total of 52 eligible participants was imported into an Excel spreadsheet. To ensure validity of the data analysis, the authors cleaned the data set by removing incomplete data (Portney and Watkins, 2015). Descriptive statistics were used to describe the demographic and clinical characteristics of the sample (mean, standard deviation, frequency).

Data analysis for objective (a) (to describe specific OPIs identified by youth post concussion) was conducted as follows. To ensure rigour, two authors (RCS, YV) independently coded each OPI from the COPM data as self-care, productivity, or leisure. An additional two members (AH, DG) of the research team were consulted to resolve 10 discrepancies. OPIs within each category (self-care, productivity, and leisure) were further coded by the first two authors (RCS, YV) independently. Self-care OPIs were coded as feeding, sleeping, showering, or other. Productivity OPIs were coded as school-related, work/volunteer-related, or other. Leisure OPIs were coded as sport-related, social-related, screen time, or other.

The complete data set was then imported into SPSS Statistics software (version 23.0) for analysis related to objectives (b) and (c) (IBM SPSS 23, 2017). To address objective (b) (to identify how performance and satisfaction ratings of OPIs change after completion of a 6-week active rehabilitation intervention), the distribution of the data was examined to determine if data was normally distributed. Paired t-test analyses were then conducted to determine if the average satisfaction and performance ratings of OPIs were significantly different pre and post intervention. The paired t-tests allowed for improved control over extraneous variables and reduction in total error variance (Portney and Watkins, 2015). For objective (c) (to explore the relationship between changes in ratings of self-reported OPIs and severity of concussion symptoms), correlations were calculated using the change in PCSI-SR13 total symptom scores and the change in COPM performance, and satisfaction ratings reported by youth ages 13 to 18 years. As this distribution was skewed and did not meet assumptions for normality, Spearman’s rho correlations were calculated. Data reported in the PCSI-SR8 was not analysed due to the small number of participants aged 9 to 12 years (n = 10). Statistical significance was set at the p ≤ 0.05 level.

Results

Demographic and injury characteristics of the sample are summarized in Table 1. The sample consisted of 52 youth (65.38% females and 34.62% males) between 2 and 178 weeks post concussion (M = 22.95, SD = 31.63). The mechanisms of injury varied, with the majority of youth having a sports/recreational play related injury (59.62%, n = 31). At intake (week zero) of the active rehabilitation intervention, the average PCSI total symptom score for youth ages 13 to 18 years was 36.90 (SD = 23.79), with a median of 32, and ranged from 1 to 91. At intake, the average PCSI total symptom score for youth ages 9 to 12 years was 15.20 (SD = 6.21), median of 15.50, and ranged from 6 to 25.

Table 1.

Participant demographics.

Demographic	n = 52
Age, years	Average = 14.42; range = 9–18
Sex, % (n)
Female	65.38 (34)
Male	34.62 (18)
Time since injury, weeks	Average = 22.92; range = 2–78; median = 13.14
Mechanism of injury % (n)
Sports/recreational play	59.62 (31)
Non-sport-related fall/injury	21.15 (11)
Motor vehicle collision	9.62 (5)
Assault	1.92 (1)
Other^a	7.69 (4)
Number of previous concussions n = 49^b % (n)
0	51.02 (25)
1–3	42.86 (21)
4–5	6.12 (3)
Pre-injury diagnoses n = 50^c
None	(30)
Anxiety	(3)
Depression	(1)
Learning disability	(7)
Attention deficit disorder/attention deficit hyperactivity disorder	(4)
Developmental disorder	(4)
Sleep disorder	(1)
Pre-injury academic performance (n = 50)^c
Below average	(3)
Average	(13)
Above average	(34)

Demographic information of study participants was collected using the ACE and demographics form. n = 52 unless otherwise specified.

^aOther reported mechanisms of injury included ‘Hit in head with ball while standing on playground’ and ‘Hit head on car door’.

^bNumber of previous concussions was not reported by three participants.

^cPre-injury mental health disorder and self-reported academic performance were not reported by two participants.

For objective (a) (to describe specific OPIs identified by youth post concussion), the specific OPIs identified by youth are reported in Figure 1. Youth reported a total of 211 OPIs, and at least one in the following areas: leisure (98.08%, n = 51); productivity (86.54%, n = 45); and self-care (26.92%, n = 14). The most frequently reported leisure OPIs were sport-related (62.73%) (for example hockey, swimming, and horseback riding) and social-related (17.27%) (for example spending time with family and friends). Additional reported leisure OPIs included colouring pictures, knitting, using electronic devices, and playing video games and instruments. The most frequently reported productivity OPIs were school-related (79.76%) (for example attending school, reading, and completing tests and homework). Other reported productivity OPIs included volunteering, preparing a resume, preparing for a summer job, and completing chores. The most frequently reported self-care OPIs were sleeping (47.06%) (for example difficulty sleeping through the night), and feeding (29.41%) (for example choosing and eating meals). Additional reported self-care OPIs included independent showering and completing an overall self-care routine.

Figure 1.

Occupational performance issues (OPIs) reported by youth with concussion.

For objective (b) (to identify how performance and satisfaction ratings of self-reported OPIs change after completion of a 6-week active rehabilitation intervention), changes in performance and satisfaction ratings of OPIs from pre to post intervention are reported in Table 2. Significant changes were found in performance (M = 2.38, SD = 2.08, t(51) = –8.23) and satisfaction (M = 2.67, SD = 2.42, t(51) = –7.95) of OPIs from pre to post intervention (p < .001). For objective (c) (to explore the relationship between changes in ratings of OPIs and severity of concussion symptoms), the average change in PCSI-SR13 total symptom scores was –14.31 (SD = 18.11), with a range of change from 15.00 to –60.00. Spearman’s rho correlation analysis revealed a weak significant relationship between change in self-reported symptoms and performance ratings (r_s = –.359, n = 42, p = .020). As self-reported symptoms decreased, occupational performance improved. However, a very weak non-significant relationship was found between self-reported symptoms and change in satisfaction ratings (r_s= –.184, n = 42, p = .243).

Table 2.

Paired samples t-test of change in COPM performance and satisfaction ratings.

	Paired differences
	Mean	Standard deviation	Standard error mean	95% confidence interval of the difference		t	df	Sig. (2-tailed)
	Mean	Standard deviation	Standard error mean	Lower	Upper	t	df	Sig. (2-tailed)
Change in performance	–2.378	2.084	0.289	–2.958	–1.797	–8.226	51	0.000
Change in satisfaction	–2.673	2.425	0.336	–3.348	–1.998	–7.948	51	0.000

COPM: Canadian Occupational Performance Measure

Discussion and implications

This study is among the first to explore the use of occupational performance as a measure of recovery for youth with concussion. A wide range of OPIs were reported by youth across all COPM domains (self-care, productivity, and leisure). While the majority of the sample had sport/recreational play-related concussion (59.62%, n = 31), they nonetheless identified school-related OPIs (31.75%) nearly as often as sport-related OPIs (32.70%). Nine percent of reported OPIs related to social activities. Changes in PCSI-SR13 total symptom scores were weakly but positively correlated with changes in COPM performance ratings, therefore indicating that the COPM may be a useful measure of recovery for youth ages 13 to 18 years with concussion.

Understanding OPIs that are identified by youth may inform the development of more targeted interventions. While the most frequently reported concussion interventions in the literature to date target physical rehabilitation (for example active rehabilitation programmes: Dobney et al., 2017; Gagnon et al., 2009, 2015; Imhoff et al., 2016; Kurowski et al., 2017; Lawrence et al., 2018), it is clear from our study findings that return-to-school and social-related activities are also important to youth.

It should be noted that the majority of participants (68%, n = 34/50) identified their pre-injury academic performance as above average. This self-identification as academic achievers may explain why school-related OPIs were largely identified as meaningful and prioritized as important to the participants. This finding is in agreement with previous literature (see for example Ransom et al., 2015), which found that a majority of symptomatic youth who identified as above average students also reported concerns regarding school performance. In addition to academics, as a small percentage of youth reported social-related OPIs (such as going to the mall, attending parties, and hanging out with friends and family), it may be important for clinicians to ask youth about social aspects of function during assessment to determine intervention needs. For these youth, social skill interventions and a focus on community integration may be important and meaningful.

The very weak and non-significant correlation between symptoms and satisfaction of OPIs reported by youth ages 13 to 18 years prompted further investigation. In reviewing the data, it was noted that change in performance and satisfaction ratings may have been influenced by the nature of the occupation itself. For instance, if a participant identified playing a seasonal sport (for example hockey) as an OPI, and the season had ended during the intervention period, their performance and satisfaction ratings may have remained the same or decreased due to a lack of opportunity to play. Also, the non-significant change in satisfaction of OPIs may be attributed to the participants’ possible change in priorities over the course of the 6-week intervention (Østensjø et al., 2008). Additionally, it is hypothesized that the self-reported academic achievers (68%, n = 34/50) may have a tendency to set higher expectations of performance, resulting in lower satisfaction ratings (Mento et al., 1992). Without an explicit goal of functional recovery, satisfaction with performance of OPIs may be vulnerable to high expectations or changing priorities.

Additional measurements may be needed to account for changing priorities or expectations. The COPM is a useful tool that assists clients in identifying important problems in everyday performance, and detecting changes in the satisfaction and performance of those problems after an intervention (Law et al., 1998; Østensjø et al., 2008). However, the COPM does not explore how the client can address their OPIs, nor why the performance issues are important to the client. Research has suggested the importance of supplementing the COPM with goal-setting and rating methods, such as the Goal Attainment Scaling (GAS), for the purpose of accountability (McDougall and Wright, 2009; Østensjø et al., 2008). Goals and goal-setting may help to understand and change youth behaviour; moreover, explicit functional goals may increase motivation and improve outcomes (Øien et al., 2009). A metacognitive intervention, The Cognitive Orientation to daily Occupational Performance (CO-OP) Approach, may be useful in enabling youth with traumatic brain injury to perform occupation-based goals, including those related to school and social activities (Hunt et al., 2019; Missiuna et al., 2010).

As client-centred clinicians, occupational therapists are well prepared to determine specific OPIs and facilitate functional goal-setting in youth recovering from concussion. Occupational therapists are competent in providing holistic occupation-based interventions that address physical, cognitive, and behavioural needs of these youth, and can facilitate the gradual resumption of activities post concussion using performance-based goals. Using measures of occupational performance, occupational therapists may contribute to the management of functional recovery from concussion through involvement in the design, delivery, and monitoring of a youth’s plan to return to meaningful activities.

Limitations and future directions

This study has some limitations worth noting. First, the sample population may not be representative of the general population of youth with post-concussion symptoms. Due to convenience sampling, the study participants largely resided in an affluent geographical area and had access to transportation to and from study appointments. Second, a larger sample size may be needed to better explore our study objectives according to demographic groups (for example sex, age, and time since injury). Future study of the role of sex, age, and time since injury in the self-report of OPIs and concussion symptoms may provide additional insight to inform more targeted rehabilitation interventions.

Based on the hypothesized phenomenon of participants setting high performance expectations, it is suggested that future studies explore use of the COPM to identify youth’s specific OPIs, alongside a goal-setting and rating scale such as the GAS. These assessments may help clinicians to identify youth’s school- and social-related OPIs, establish client-centred goals, decide on a targeted intervention, and measure functional recovery after an intervention.

Conclusion

Youth with concussion ages 9 to 18 years most frequently identified OPIs in sport-, school-, and social-related activities. Positive changes were found in occupational performance of self-identified OPIs following a 6-week active rehabilitation intervention. Among youth aged 13 to 18 years, self-reported reductions in concussion symptoms were weakly associated with self-reported increases in performance of OPIs post intervention. Findings suggest that the COPM may be useful in measuring functional recovery from concussion in these youth. Future studies should investigate the use of the COPM in conjunction with the GAS to measure functional recovery of youth concussion.

Key findings

The Canadian Occupational Performance Measure may be useful in measuring functional recovery in youth post concussion.

Positive changes were found in occupational performance following a 6-week active rehabilitation programme.

What this study has added

This study provides evidence that a measure of occupational performance may provide meaningful insight into the functional recovery of concussion, and can help identify targeted approaches to paediatric concussion management. It also provides evidence that establishes occupational therapy as a profession that is uniquely positioned to support gradual return to meaningful activity in concussion rehabilitation.

Footnotes

Acknowledgements

We extend our gratitude to the participants and their families for contributing to this study.

Research ethics

Ethical approval was granted by Holland Bloorview Kids Rehabilitation Hospital Research Ethics Board (REB#16-636) and University of Toronto Research Ethics Board (REB#36-270) in 2016.

Consent

Written informed consent was obtained from all participants and their parents.

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship, or publication of this article.

Funding

The authors disclosed receipt of financial support for the research study from Scotiabank.

Contributorship

Robyn Chen Sang and Yasira Vawda were responsible for study conceptualization, literature review, data analysis, interpretation, and manuscript preparation. Dayna Greenspoon was responsible for study conceptualization, data collection, analysis, interpretation, and manuscript preparation. Nick Reed was responsible for study conceptualization, interpretation of results, manuscript preparation, and study oversite. Anne Hunt was responsible for study conceptualization, data collection, analysis, interpretation, and manuscript preparation. All authors reviewed, edited, and approved the final version of the manuscript.

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