title: SCAT2 and SCAT3 scores at baseline and after sports-related mild brain injury/concussion: qualitative synthesis with weighted means.
abstract: OBJECTIVE
  Identify all Sport Concussion Assessment Tool (SCAT2/3) studies, compare baseline and postconcussion results.
  
  
  METHODS
  Systematic review (qualitative synthesis, weighted means).
  
  
  METHODS
  18 databases, 9 grey literature resources searched for SCAT2/3 data; 9150 articles identified, titles/abstracts assessed/data-entry independently by two reviewers.
  
  
  METHODS
  Any studies reporting partial/complete SCAT2/3 data.
  
  
  RESULTS
  21 studies with data (partial/complete data 16 SCAT2 (4087 athletes); 5 SCAT3 (891). Newcastle-Ottawa risk-of-bias scale: studies with maximum possible score of 4, 85% scored 3 or 4; studies with maximum possible score of 6, 75% scored 5 or 6. SCAT2 high schoolers: weighted mean score for symptoms 18.46 (22=no symptoms), Balance Error Scoring System (BESS) 26.14, Standardised Assessment of Concussion (SAC) 26.00 and SCAT2 total 88.63. Collegiate/adults weighted means: symptoms 20.09, BESS 25.54, SAC 27.51 and total SCAT2 91.20. Between-study and within-study variability similar to those of the high schoolers. Limited variability between genders. Only 2 studies report baseline and postconcussion scores and 9 partial scores, but data are too limited to provide weighted average scores.
  
  
  CONCLUSIONS
  Group mean baseline SCAT scores for high school and collegiate athletes are similar, with minimal gender differences; baseline symptoms show more variability than other components. There are minimal data for elementary students and professionals, no data for adult non-collegiate athletes. Two studies provide preconcussion and postconcussion scores. No data on minimal significant clinical differences to guide players/coaches in withdrawing from a game in progress and deciding when recovery is complete and play can be resumed. The SCAT needs supplementing with clinical and neuropsychological return-to-play assessments.
authors.affiliation: Department of Family Medicine, Faculty of Medicine , Health Sciences Centre, University of Calgary , Calgary, Alberta , Canada.
authors.forename: Roger E
authors.initials: RE
authors.lastname: Thomas
authors.affiliation: CEREBRO-Brain Health Center , Braga , Portugal.
authors.forename: Jorge
authors.initials: J
authors.lastname: Alves
authors.affiliation: Knowledge Resource Service, Alberta Health Services , Holy Cross Centre , Calgary, Alberta , Canada.
authors.forename: Marcus M
authors.initials: MM
authors.lastname: Vaska
authors.affiliation: Clinical Academic Center-Braga , Braga , Portugal.
authors.forename: Rosana
authors.initials: R
authors.lastname: Magalhães
keywords: Concussion; Evidence based review; Measurement; Sports