| Study | Study objective | Study design | Study sample | Symptom measure | Psychometric evidence |
| Mailer (2008)19 | Test-retest reliability of self-report symptom measures | Within-subjects, repeated measures | 126 non-concussed middle school students (mean age = 13.1 yr)Sport: unspecified | GSS; 16 items | Reliability: moderate internal consistency for symptom severity (0.86) and duration (0.84) scales. Test-retest reliability good to excellent for the total symptom severity scale (ICC = 0.88 to 0.93) and moderate to good reliability for the individual symptoms severity (ICC = 0.65 to 0.89) and duration (ICC = 0.56 to 0.96) scalesValidity: not reportedSerial use: 45 day interval between two ratings. No RCI |
| Gioia (2008)20 | Demonstrate psychometric properties of the ACE | Retrospective, repeated measures | 354 parents of children ages 3–18 with concussionSport: multiple (50% of sample) | ACE; 26 items (yes/no response) | Reliability: moderate item-total correlations correlation with the total score for most of the symptoms. Internal consistency was moderate to high (α = 0.82). Inter-rater reliability was appropriateValidity: predictive: ACE symptom score predicted parent and patient PCSI reports but was less related to pre-concussion baseline ratings, providing evidence of validity for detecting mild TBI; Construct: four factors identifiedSerial use: average 7 days post-injury; multiple follow-up visits; no RCI |
| Gagnon (2005)21 | Evaluate children’s self-efficacy relation to the practice of physical activities prior to and after concussion | Case control | 34 children with concussion ages 8–16Sport: Falls most common but sports injuries also present | RPCSQ; 16 items | Reliability: not reportedValidity: concurrent (clinical group differences): Concussed versus non-concussed) found at 1,4 and 12 weeks post-injurySerial use: significant decrease in symptoms across 3 visits; no RCI |
| Ayr (2009)22 | Investigate long-term dimensions of post-concussive symptoms | Prospective longitudinal cohort | 186 children with concussion ages 8–15 (mean age = 11.96 yr) and their parentsSport: Unspecified, sports and recreation reported to be most common cause | HBI—parent and child report forms; 50 items | Reliability: not reportedValidity: construct: three replicable factors identified (cognitive, somatic and emotional symptoms) at baseline and 3-months post injury. Fourth behavioural symptom dimension identified at baseline, not at 3-months. Moderate parent-child correlations between cognitive and somatic symptoms at baseline; weak/non-significant correlations between emotional and behavioural symptoms. At three months, moderate correlations between cognitive symptoms and weak/non-significant correlations were identified for somatic, emotional and behavioural symptomsSerial use: two post-injury administrations: 1 week, 3 months. No RCI |
| Yeates (2001)23 | Examine the prevalence and correlates of neurobehavioral symptoms during the first year following concussion | Prospective longitudinal cohort | 122 parents of children ages 6–12 years with either concussion or orthopaedic injuriesSport: unspecified | Post-injury symptom checklist—parent report; 30 items (15 considered) | Reliability: not reported (previous study showed a 6 month test-retest mean within group correlation 0.55)Validity: concurrent: group differences in 4 factors (emotional, behavioural, cognitive and somatic) between concussed and orthopaedic groups. Cognitive/somatic symptoms declined over time, while emotional/behavioural symptoms increased. Convergent: emotional/behavioural symptoms were predicted by injury severity, concurrent cognitive functioning soon after the injury and concurrent parent and family burden later in timeSerial use: three administrations, six month intervals. No RCI |
| Yeates (1999)24 | Examine the incidence and neuropsychological, behavioural and neuroimaging correlates of post-concussive symptoms. | Prospective longitudinal cohort | 34 children with concussion ages 8–15 years and their uninjured sibling.Sport: unspecified | HBI; 62 items | Reliability: not reportedValidity: concurrent: group differences for concussed from baseline to 3 months with cognitive and somatic symptoms more so than controlsSerial use: Retrospective baseline and 3 months two post-injury. No RCI |
ACE, acute concussion evaluation, GSS, graded symptom scale; HBI, health and behaviour inventory; PCSI, post-concussion symptom inventory; RCI, reliable change indices; RPCSQ, Rivermead post-concussion symptom questionnaire; TBI,