Video Abstract

Video Abstract

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OBJECTIVES

To determine the association between early screen time (7–10 days postinjury) and postconcussion symptom severity in children and adolescents with concussion, as compared to those with orthopedic injury (OI).

METHODS

This was a planned secondary analysis of a prospective longitudinal cohort study. Participants were 633 children and adolescents with acute concussion and 334 with OI aged 8 to 16, recruited from 5 Canadian pediatric emergency departments. Postconcussion symptoms were measured using the Health and Behavior Inventory at 7 to 10 days, weekly for 3 months, and biweekly from 3 to 6 months postinjury. Screen time was measured by using the Healthy Lifestyle Behavior Questionnaire. Generalized least squares models were fit for 4 Health and Behavior Inventory outcomes (self- and parent-reported cognitive and somatic symptoms), with predictors including screen time, covariates associated with concussion recovery, and 2 3-way interactions (self- and parent-reported screen time with group and time postinjury).

RESULTS

Screen time was a significant but nonlinear moderator of group differences in postconcussion symptom severity for parent-reported somatic (P = .01) and self-reported cognitive symptoms (P = .03). Low and high screen time were both associated with relatively more severe symptoms in the concussion group compared to the OI group during the first 30 days postinjury but not after 30 days. Other risk factors and health behaviors had stronger associations with symptom severity than screen time.

CONCLUSIONS

The association of early screen time with postconcussion symptoms is not linear. Recommending moderation in screen time may be the best approach to clinical management.

What’s Known on This Subject:

The recommendation to restrict screen time after concussion largely reflects expert opinion. In 1 randomized controlled trial, children instructed to abstain from screen time after concussion had a shorter median recovery time than children permitted to engage in screen time.

What This Study Adds:

Both low and high early screen time predicted more severe symptoms after concussion relative to orthopedic injury during the first 30 days postinjury, but not after 30 days. Other variables had stronger associations with symptom severity than screen time.

Physicians often recommend that children and adolescents limit or avoid use of computers, televisions, phones, and other devices with screens after concussion.1  Some clinical practice guidelines recommend avoiding screens for 1 to 2 days before gradually resuming use as tolerated,2  whereas other guidelines mention gradually returning to screen time in the context of return-to-school strategies3  or imply that screen time restrictions are a component of “cognitive rest.”4  However, advising complete cognitive rest (“cocooning”), including a prohibition on screen time, could conceivably have negative effects on children and adolescents (eg, social isolation, psychological distress).57  The impact of screen time after concussion had not been empirically studied until a recent randomized controlled trial by Macnow et al.8  Patients aged 12 to 25 years (N = 125) who presented to an emergency department (ED) with concussion were permitted screen time as tolerated or instructed to abstain for the first 48 hours postinjury.8  Symptom ratings were collected daily for 10 days. The group permitted to use screens as tolerated had a longer median time until recovery (8.0 days [interquartile range: 3.0 to >10.0 days]) than the group instructed to abstain from screen time (3.5 days [interquartile range: 2.0 to >10.0 days]).

Several important questions about screen time after concussion remain unanswered. The long-term effects of screen time on concussion recovery are still unknown. Although screen time within the first 48 hours postinjury could contribute to temporary symptom exacerbation, its longer-term impact has not been examined empirically. The effects of time spent on screens after the first 48 hours postconcussion remain unknown. Whether less screen time facilitates recovery from concussion specifically or benefits the well-being of youth regardless of concussion (eg, decreased sedentary behavior) is unclear. Relatedly, the mechanisms underlying any benefit from screen time restrictions are unknown; however, they may be associated with increased physical activity, which is known to accelerate concussion recovery.9  The design of the Macnow et al study (ie, 2-arm clinical trial)8  provides little insight into the association of concussion recovery with the full naturalistic range of screen time. Finally, understanding the importance of screen time relative to other known predictors of recovery, such as preinjury symptoms and early physical activity, would help contextualize clinical recommendations.1013 

Our current observational study addresses these questions by exploring the full naturalistic range of screen time over the first 7 to 10 days postinjury and its association with postconcussion symptoms over the following 6 months, while controlling for other predictors of screen time (ie, propensity for higher screen time) and symptom recovery. Furthermore, we compare the association of screen time with symptom recovery in children and adolescents with concussion to those with orthopedic injury (OI) to determine whether screen time is uniquely detrimental after concussion. The OI group controls for factors other than brain injury that can contribute to postconcussion symptom severity, such as pain and posttraumatic stress. We predicted an interaction between injury type (ie, concussion versus OI) and screen time, such that higher levels of early screen time would predict greater postconcussion symptom severity over time in those with concussion relative to those with OI.

This study was a planned secondary data analysis of the Advancing Concussion Assessment in Pediatrics (A-CAP) study,14  a prospective longitudinal cohort study of children and adolescents who sustained a concussion or OI. Participants were recruited from 5 EDs within the Pediatric Emergency Research Canada network from September 2016 to December 2018.

Participants ages 8 to 16 years old who presented to the ED within 48 hours of sustaining a concussion or OI were screened for eligibility. Children and adolescents with concussion were eligible to participate if they had experienced blunt head trauma resulting in 1 or more of the following criteria generally consistent with the World Health Organization definition of mild traumatic brain injury (TBI): observed loss of consciousness, a Glasgow Coma Scale score of 13 to 14, or 1 or more acute signs or symptoms of concussion (eg, confusion, headache). Children and adolescents with OI were eligible if they sustained upper or lower extremity fractures, sprains, or strains because of physical trauma, and had an Abbreviated Injury Scale15  score of 4 or less.

Exclusion criteria specific to the concussion group included neurologic deterioration, neurosurgical intervention, loss of consciousness >30 minutes or posttraumatic amnesia > 24 hours, and bodily injuries with an Abbreviated Injury Scale score >4. Exclusion criteria for the OI group included head trauma, acute signs and symptoms of concussion, or injury requiring surgical intervention or procedural sedation. Additional exclusion criteria for both groups included hypoxia, hypotension or shock; non-English speaking; previous TBI requiring overnight hospitalization; concussion within the past 3 months; history of severe neurologic or neurodevelopmental disorder; psychiatric hospitalization in the previous year; administration of sedative medicine before ED data collection; alcohol or drug use at time of injury; and legal guardian not present.

The A-CAP study protocol was published previously.14  In brief, research personnel collected demographic information, injury details, and acute signs or symptoms of concussion in the ED from medical records and medical personnel using a standardized case report form. Follow-up assessments were targeted for 7 days, 3 months, and 6 months postinjury. At each follow-up, participants and their parents each completed questionnaires regarding symptoms and health behaviors. At the first follow-up, parents also completed measures of preinjury symptoms and health behaviors. In addition, participants and their parents completed remote ratings of postconcussion symptoms weekly during the first 3 months and biweekly from 3 to 6 months postinjury. All participants provided written informed consent or assent. The study was approved by each participating institution’s ethics review board.

The Health and Behavior Inventory (HBI),16  which is recommended as a primary outcome measure in the National Insitute of Neurological Disorders and Stroke Common Data Elements for sport-related concussion,17  was used as the primary outcome. The self- and parent-proxy versions provide 2 separate scales for cognitive and somatic symptoms, with higher scores reflecting a higher frequency of symptoms.

The Healthy Lifestyle Behaviors Questionnaire (HLBQ) assessed parent-proxy and self-reported pre- and postinjury engagement in health behaviors, including physical activity and rest, cognitive activity and rest, diet, sleep, and screen time. The scale measuring screen time was used as the primary predictor. Each participant and parent rated the frequency and duration that the child or adolescent engaged in screen time over the previous 7 days. A 5:2 weighted average for weekdays and weekends was computed to provide an estimated weekly average.18  The total weighted average was used in analyses. Supplemental Information provides information on the development and validation of the HLBQ (see Supplemental Document 1).

Descriptive statistics summarized baseline characteristics. To examine the association between screen time and postconcussion symptoms over time, we fit 4 generalized least squares models, 1 for each of the 4 HBI outcome measures: self-reported somatic and cognitive symptoms and parent-reported cognitive and somatic symptoms. We included both self- and parent-reported screen time as predictors, for 3 reasons: (1) the scale that more accurately reflects a participant’s actual screen time is unclear, (2) self- and parent-reported screen time correlated only moderately (Spearman’s r = .60) in our sample, and (3) we evaluated their combined predictive contribution (ie, joint effect) to postconcussion symptoms. Generalized least squares were applied with a continuous first-order autoregressive19  structure, with nesting of patients within sites, allowing for correlated residuals from repeated measurement of symptoms and to account for potential clustering because of multisite recruitment. A common set of 27 covariates previously shown to be associated with concussion outcomes1012  and parent ratings of preinjury screen time and child and parent ratings of other preinjury and postacute lifestyle behaviors (eg, sleep, physical activity) were included in all models to help isolate the effect of postinjury screen time and reduce potential confounding between the risk for poor recovery and screen time use (eg, children with lower risk for prolonged recovery returning to screen time more quickly) (see Supplemental Document 2, Supplemental Table 3).

To allow for nonlinearity, restricted cubic splines20  were applied to selected continuous variables considering allowable degrees-of-freedom to maintain an approximate 10:1 observation-to-parameter ratio. For self- and parent-reported screen time and preinjury HBI somatic and cognitive symptoms, 4 knots (ie, pivot points) at strategically-spaced quantiles (0.05, 0.35, 0.65, 0.95) were afforded. For age, social deprivation index, material deprivation index, and preinjury parent ratings of HBI somatic and cognitive symptoms, 3 knots were afforded (0.10, 0.5, 0.90). Linearity was assumed for all HLBQ covariates.

For all models, the initial specification featured 2 sets of 3-way interactions inclusive of both linear and nonlinear components of a continuous predictor’s effect. The first set of interactions involved self-reported screen time, group, and time, and the other consisted of parent-reported screen time, group, and time. To simplify the models, we applied a stepwise backward elimination procedure to sequentially remove factors with the largest P value until only P < .05 remained (on the basis of a multiple degrees-of-freedom Wald χ2 test, if applicable). As the predictors of primary interest, the main effects of self- and parent-reported screen time were exempted from elimination. Listwise deletion was applied for all models.

To assess the effect of individual predictors and covariates for each model, we report: (1) the Wald χ2 and associated P value, (2) Wald χ2 minus degrees-of-freedom for evaluating the relative contribution among predictors, and (3) partial effect plots to illustrate the estimated covariate-adjusted relationship between our main predictors of interest and HBI outcomes. Analyses were performed by using R version 4.0.3 (rms package).20,21 

A total of 967 children and adolescents (58.1% male) were recruited. See Figure 1 for a participant flow diagram. 829 participants completed the postacute assessment. Of those 829, 117 (14%) participants had incomplete covariate data; therefore, 712 participants were included in all 4 final models. Baseline characteristics are summarized in Table 1. There were no significant differences between those who were included or excluded in the final models in age, sex, other demographics, or preinjury history (see Supplemental Document 2, Supplemental Table 4).

FIGURE 1

Participant flow diagram.

FIGURE 1

Participant flow diagram.

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TABLE 1

Demographic and Clinical Characteristics of the Total Study Sample

NConcussionNOrthopedic Injury
Age, median (IQR) 633 12.0 (10.2–14.4) 334 12.5 (10.9–14.3) 
Sex, n (%) 633  334  
 Male  379 (59.9)  183 (54.8) 
 Female  254 (40.1)  151 (45.2) 
Familial information     
 Parental education, n (%) 549  275  
  High school or less  86 (15.7)  43 (15.6) 
  Trades or 2-y college  164 (29.9)  83 (30.2) 
  Bachelor’s degree  206 (37.5)  93 (33.8) 
  Higher than Bachelor’s degree  93 (16.9)  56 (20.4) 
Social deprivation index, percentile, median (IQR) 599 41.0 (23.0–66.0) 319 43.0 (23.5–66.5) 
Maternal deprivation index, percentile, median (IQR) 599 28.0 (11.0–54.5) 319 27.0 (12.0–56.0) 
Preinjury history, n (%)     
 History of migraine 616 34 (5.5) 329 23 (7.0) 
 Previous concussion symptom and duration 620  327  
  No previous concussion  421 (67.9)  237 (72.5) 
  <1 wk symptom duration  121 (19.5)  54 (16.5) 
  1+ week symptom duration  78 (12.6)  36 (11.0) 
Retrospective preinjury HBI somatic symptoms, median (IQR) 555 2.0 (0.0–4.0) 281 1.0 (0.0–3.0) 
Retrospective preinjury HBI cognitive symptoms, median (IQR) 555 8.0 (2.0–15.0) 281 6.0 (0.0–12.0) 
Screen time,a mean (SD)     
 Preinjury parent 553 5.4 (2.9) 281 5.9 (3.2) 
 Postacute parent 541 3.9 (3.1) 272 6.0 (3.1) 
 Postacute self 521 4.7 (3.8) 274 6.1 (3.8) 
NConcussionNOrthopedic Injury
Age, median (IQR) 633 12.0 (10.2–14.4) 334 12.5 (10.9–14.3) 
Sex, n (%) 633  334  
 Male  379 (59.9)  183 (54.8) 
 Female  254 (40.1)  151 (45.2) 
Familial information     
 Parental education, n (%) 549  275  
  High school or less  86 (15.7)  43 (15.6) 
  Trades or 2-y college  164 (29.9)  83 (30.2) 
  Bachelor’s degree  206 (37.5)  93 (33.8) 
  Higher than Bachelor’s degree  93 (16.9)  56 (20.4) 
Social deprivation index, percentile, median (IQR) 599 41.0 (23.0–66.0) 319 43.0 (23.5–66.5) 
Maternal deprivation index, percentile, median (IQR) 599 28.0 (11.0–54.5) 319 27.0 (12.0–56.0) 
Preinjury history, n (%)     
 History of migraine 616 34 (5.5) 329 23 (7.0) 
 Previous concussion symptom and duration 620  327  
  No previous concussion  421 (67.9)  237 (72.5) 
  <1 wk symptom duration  121 (19.5)  54 (16.5) 
  1+ week symptom duration  78 (12.6)  36 (11.0) 
Retrospective preinjury HBI somatic symptoms, median (IQR) 555 2.0 (0.0–4.0) 281 1.0 (0.0–3.0) 
Retrospective preinjury HBI cognitive symptoms, median (IQR) 555 8.0 (2.0–15.0) 281 6.0 (0.0–12.0) 
Screen time,a mean (SD)     
 Preinjury parent 553 5.4 (2.9) 281 5.9 (3.2) 
 Postacute parent 541 3.9 (3.1) 272 6.0 (3.1) 
 Postacute self 521 4.7 (3.8) 274 6.1 (3.8) 

IQR, interquartile range.

a

Weighted 5:2 for weekdays and weekends.

Our hypothesis that more early screen time would predict greater symptom severity over time in children and adolescents with concussion relative to those with OI was only partially supported. The interaction between screen time and group was not significant for parent-reported cognitive symptoms or self-reported somatic symptoms (see Table 2). In other words, the association of screen use during the postacute recovery period with these outcomes did not differ by group (see Fig 3). The interaction between self-reported screen time and group was significant for self-reported cognitive symptoms (P = .03) and parent-reported somatic symptoms (P = .01; see Table 2); however, the relationship between screen time and group differences in postconcussion symptoms was not linear. Contrary to our hypothesis, group differences in symptom severity (concussion > OI) were larger at the 25th and 50th quantiles of screen time than at the 75th quantile (see Fig 3). Thus, higher screen time was not uniformly associated with more symptoms in the concussion group relative to the OI group, although group differences were also larger at the highest levels of screen time (eg, 90th quantile).

TABLE 2

Summary of Wald χ2 for Screen Time (Self-PA, Parent-PA, and Joint Effect) Across the 4 Models

Outcome
HBI Somatic SelfHBI Cognitive SelfHBI Somatic ParentHBI Cognitive Parent
Factorχ2 d.f.pχ2 d.f.pχ2 d.f.pχ2 d.f.p
Screen time self-PA 34.24 12 <.001 10.51 .11 18.20 .006 5.23 .16 
 All interactions 20.18 .02 8.67 .03 10.82 .01 — — — 
 Nonlinear 23.11 .003 8.99 .06 10.10 .04 5.21 .07 
Screen time self-PA: group — — — 8.67 .03 10.82 .01 — — — 
 Nonlinear — — — 8.38 .02 6.57 .04 — — — 
Screen time self-PA: time 20.18 .02 — — — — — — — — — 
 Nonlinear 18.46 .02 — — — — — — — — — 
Screen time parent-PA 2.12 .55 9.15 .03 43.79 12 <.001 9.93 .02 
 All interactions — — — — — — 29.33 <.001 — — — 
 Nonlinear 1.88 .39 0.73 .69 21.22 .007 4.71 .10 
Screen time parent-PA: time — — — — — — 29.33 <.001 — — — 
 Nonlinear — — — — — — 24.28 .002 — — — 
Screen time self-PA or parent-PA (JOINT TEST) 34.47 15 .003 19.48 .02 57.53 18 <.001 16.47 .01 
Outcome
HBI Somatic SelfHBI Cognitive SelfHBI Somatic ParentHBI Cognitive Parent
Factorχ2 d.f.pχ2 d.f.pχ2 d.f.pχ2 d.f.p
Screen time self-PA 34.24 12 <.001 10.51 .11 18.20 .006 5.23 .16 
 All interactions 20.18 .02 8.67 .03 10.82 .01 — — — 
 Nonlinear 23.11 .003 8.99 .06 10.10 .04 5.21 .07 
Screen time self-PA: group — — — 8.67 .03 10.82 .01 — — — 
 Nonlinear — — — 8.38 .02 6.57 .04 — — — 
Screen time self-PA: time 20.18 .02 — — — — — — — — — 
 Nonlinear 18.46 .02 — — — — — — — — — 
Screen time parent-PA 2.12 .55 9.15 .03 43.79 12 <.001 9.93 .02 
 All interactions — — — — — — 29.33 <.001 — — — 
 Nonlinear 1.88 .39 0.73 .69 21.22 .007 4.71 .10 
Screen time parent-PA: time — — — — — — 29.33 <.001 — — — 
 Nonlinear — — — — — — 24.28 .002 — — — 
Screen time self-PA or parent-PA (JOINT TEST) 34.47 15 .003 19.48 .02 57.53 18 <.001 16.47 .01 

d.f., degrees of freedom; HBI, Health and Behaviour Inventory; PA, postacute; —, not applicable.

In all models, symptom severity was higher in the concussion group than in the OI group while holding all other covariates constant over the first 30 days post injury (See Fig 3). Group differences were negligible after 30 days postinjury regardless of screen time (See Fig 3).

Visual inspection of the relationship between screen time and symptom severity within the concussion group reveals subtle U-shaped distributions in 3 of the 4 models (ie, self-reported somatic, self-reported cogntive, and parent-reported somatic; See Fig 3). Specifically, children and adolescents with concussion who reported the lowest (<25th quantile) and highest screen time (>90th quantile) during the first 7 to 10 days postinjury reported more cognitive and somatic symptoms than those in the25th to 75th quantile of screen time (See Fig 3). Similarly, parents of children with concussion who reported the lowest or highest levels of early screen time (<25th and >90th quantile) reported more somatic symptoms than parents of children and adolescents in the 25th to 75th quantile (See Fig 3). We conducted a supplementary analysis using a validated risk score (“5P”)10  instead of the full set of 27 covariates, to determine if higher risk for developing persistent symptoms moderated the relationship between screen time and concussion recovery. Children and adolescents with concussion with the worst prognosis had similar recovery trajectories regardless of their early screen time (see Supplemental Document 3, Supplemental Fig 69).

For all models (see Fig 2A–D), time since injury, group, and preinjury cognitive and somatic symptom severity were more strongly associated with parent- and self-reported symptom severity than self- and parent-reported screen time. Self- and parent-reported screen time accounted for only 0.6% to 3.5% of the proportion of total predictive ability (ie, individual Wald X2  divided by total Wald X2 ) derived from all predictors across the 4 models, compared to 10.3% to 39.6% for time since injury and 2.8% to 14.2% for injury group. Preinjury cognitive symptoms accounted for 60.8% and 19.9% of total predictive ability in models for parent- and self-rated cognitive symptoms. Preinjury somatic symptoms accounted for 21.1% and 9.2% of total predictive ability for parent- and self-rated somatic symptoms.

FIGURE 2

Wald χ2 minus degrees-of-freedom for all (retained) predictors across the models. A, HBI somatic (S) model. B, HBI cognitive (S) model. C, HBI somatic (P) model. D, HBI cognitive (P) model.

FIGURE 2

Wald χ2 minus degrees-of-freedom for all (retained) predictors across the models. A, HBI somatic (S) model. B, HBI cognitive (S) model. C, HBI somatic (P) model. D, HBI cognitive (P) model.

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FIGURE 3

Partial effect plots showing screen time effect for concussion across the model.

FIGURE 3

Partial effect plots showing screen time effect for concussion across the model.

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Several other demographic factors and health behaviors were also important predictors of symptoms regardless of group membership. Female sex predicted higher parent-reported somatic and self-reported somatic and cognitive symptom severity. More postacute napping, more preinjury screen time, and older age also predicted higher self- and parent-reported cognitive symptoms, and more self-reported sleep in the postacute recovery period was associated with fewer self-reported cognitive symptoms.

This study sought to assess the association between screen time during the first 7 to 10 days postinjury and postconcussion symptom severity over the following 6 months in those with concussion or OI. After controlling for other factors associated with screen time and symptom persistence, greater screen time was not consistently associated with increased postconcussion symptoms. The association between screen time and postconcussion symptoms differed between the concussion and OI groups for only 2 of 4 symptom measures; and for these outcomes, higher screen time was not consistently associated with more symptoms or larger group ifferences (ie, concussion versus OI) in symptoms. Moreover, when present, group differences as a function of screen time were limited to the first 30 days postinjury of the 6-month follow-up period. Although the Macnow et al5  clinical trial demonstrated that reducing screen time in the first 48 hours postinjury may offer short-term benefits, small group differences in our sample after 30-days postinjury suggest that early screen time is not detrimental for long-term recovery in children and adolescents with concussion.

A novel aspect of the current study was the examination of concussion recovery in relationship to the full naturalistic range of screen time. The screen time abstinence group in Macnow et al (2021) spent an average of 45 minutes per day on screens compared to 3.5 hours per day in the unrestricted screen time group, indicating a comparison of less to more screen time, rather than none to some. This comparison, while important, provides little insight into the association of the full naturalistic range of screen time with concussion recovery. In the current study, the association between screen time and symptom severity was not linear. Participants in the concussion group with low screen time (<25th percentile) reported more postconcussion symptoms relative to those in the OI group than did those with moderate screen time (25–75th percentile). This finding has at least 2 possible explanations. First, a child or adolescent with more severe acute symptoms may self-limit their screen time if it is bothersome or their health care provider or parent may be more likely to restrict their screen use. However, we statistically adjusted for acute symptom severity and other risk factors for protracted recovery, making this explanation less likely. Second, screen time is often used to interact with friends and family or for other tasks like school work. Undue restrictions from screen time after concussion could prevent access to social support or disrupt routines and increase emotional distress,22  worsening symptoms. In healthy young adults, separation from mobile devices (eg, texting, answering phone calls) can lead to increased physiologic arousal23  and higher self-reported anxiety,2325  especially for heavy phone users.25 

The “goldilocks” effect we observed in our sample, whereby moderate levels of screen time were associated with less pronounced group differences in symptoms compared to low and high screen use, is not unique to children and adolescents with concussion. The association between screen time and well-being is similarly nonlinear in healthy adolescents.26  In the digital age, too little screen time may limit meaningful social connections or disrupt routines, whereas too much may disrupt sleep or interfere with engagement in other important activities, such as recreation.26  As is true for the return to physical activity after concussion,13  moderation in screen time may be a helpful principle in concussion management.

Consistent with previous studies, greater preinjury cognitive and somatic symptoms,27  adolescent age,10,12  and female sex12,28  were associated with more severe postconcussion symptoms over time. These variables had a larger effect on symptom severity than screen time. Other lifestyle behaviors also predicted worse symptoms, including more postacute napping, less sleep, and more preinjury screen time.

Our study has several limitations. We only measured the duration of screen time. We did not assess the timing (eg, concentrated versus dispersed), quality (eg, active versus passive), or nature (eg, watching television versus social connection) of use. These may be important moderators of the association between screen time and postconcussion symptoms. Second, when parent and self-reports of screen time were discrepant, we could not verify which was more accurate. We used the more conservative estimate of screen time when a large discrepancy existed and truncated values when the sum of reported screen time and sleep duration was >24 hours. Only a small proportion of participants met these criteria (9% for self-report and 7.3% for parent-report). Third, because recruitment occurred in EDs, the results may not generalize to children or adolescents who do not seek care or seek alternative care after injury. We also do not have detailed data on the timing of follow-up care, which could impact recovery. Fourth, children and adolescents who enrolled in the current study may differ from those who did not enroll leading to selection bias. Finally, future work is needed to understand if certain individuals, such as those with vestibulocular dysfunction, are more sensitive to screen use postconcussion.

High screen time in the first 7 to 10 days postinjury was not strongly associated with worse symptoms after concussion, especially after the first 30 days postinjury, and low screen time was also associated with relatively more postconcussion symptoms. Moreover, other pre- and postinjury risk factors were more important than screen time in predicting postconcussion symptoms. These findings support advising moderation rather than blanket restrictions in screen time, especially beyond the first 48 hours, for children and adolescents postconcussion.

Dr Cairncross conceived of the current substudy, wrote the first draft of the manuscript, contributed to the interpretation of statistical analyses, and critically reviewed the manuscript; Dr Yeates conceptualized and designed the larger parent study, conceived of the current substudy, contributed to interpretation of statistical analyses, and critically reviewed the manuscript; Dr Tang conceived of the current substudy, analyzed the data and constructed the figures, and critically reviewed the manuscript; Drs Beauchamp, Craig, Doan, Zemek, and Kowalski conceptualized and designed the larger parent study, contributed to interpretation of statistical analyses, and critically reviewed the manuscript; Drs Silverberg and Madigan conceived of the current substudy, contributed to interpretation of statistical analyses, and critically reviewed the manuscript; and all authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

FUNDING: Canadian Institutes of Health Research grant (FDN143304). Dr Yeates was supported by a Ronald and irene Ward Chair in Pediatric Brain Injury from the Alberta Children’s Hospital Foundation.

CONFLICT OF INTEREST DISCLOSURES: Dr Yeates is an author of the Health and Behavior Inventory but derives no income from the use of the scale, which is publicly available for free. Dr Zemek is the cofounder, Scientific Director, and a minority shareholder in 360 Concussion Care, an interdisciplinary concussion clinic. The remaining authors have no conflicts of interest to report.

COMPANION PAPER: A companion to this article can be found online at www.pediatrics.org/cgi/doi/10.1542/peds.2022-058835.

A-CAP

Advancing Concussion Assessment in Pediatrics

ASHS

Adolescent Sleep Hygiene Scale

CRSP

Children’s Report of Sleep Patterns

ED

emergency department

HBI

Health and Behavior Inventory

HBSC

Healthy Behaviors in School-aged Children

HLBQ

Healthy Lifestyle Behaviours Questionnaire

OI

orthopedic injury

TBI

traumatic brain injury

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Supplementary data