Table 1

Characteristics of studies meeting inclusion criteria:

(A) Assessment of persistent symptoms following SRC.
Study Study design Method of assessment Setting (country) Participants Controls or comparison group (n) Duration of symptoms
n sex Age (mean (SD) years) Sport
Kozlokski et al (2013)26 Cross-sectionalGraded exercise testUniversity-based sports medicine clinic (USA)3417M:17F25.9 (10.9)Mixed (SRC and non-SRC), no details on sport22Average time from injury=226 days
Leddy et al (2015)12 Case seriesGraded exercise testUniversity-based concussion clinic (USA)12869M:59FPhysiological group: 28.0 (13.9); C/V group: 26.4 (13.0)Mixed (SRC and non-SRC), no details on sportNil>21 days
Clausen et al (2016)22 Cross-sectionalGraded exercise testUniversity-based concussion clinic (USA)9All femaleMean 23.0 (6.0)Soccer, basketball, volleyball13>6 weeks (and <12 weeks)
Ellis et al (2015)27 Cross-sectionalVestibulo-ocular testingConcussion clinic (Canada)249M:15F16.0 (1.6)Baseball, basketball, skating, football, hockey, skiing, snowboarding, soccer, volleyball, other77 with acute SRCMedian time from injury=69.5 days
Heyer et al (2016)13 Case seriesTilt tableHospital-based paediatric headache clinic (USA)348M:26FRange: 13–18Mixed (SRC and non-SRC), no details on sportNil>21 days
Gosselin et al (2012)28 Cross-sectionalEEGUniversity health centre (Canada)4421M:23F30.3 (11)Mixed (SRC and non-SRC), no details on sport40Average time from injury=7.6 months (SD 8.4)
Chen et al (2007)14 Cross-sectionalfMRIUniversity-based sports medicine clinic (Canada)18All maleLow PCS group: 26.9 (5.6); high PCS group: 30.8 (5.8)No details on sport10>1 month
Chen et al (2008)29 Cross-sectionalfMRIUniversity-based sports medicine clinic (Canada)40All maleNo depression group: 26.0 (5.6); mild depression group: 29.0 (6.7); moderate depression group: 30.0 (3.4)No details on sport16Average time from injury=4.9 (SD 4.7) −7.3 (SD 9.6) months
Chen et al (2008)30 Case seriesfMRIUniversity-based sports medicine clinic (Canada)9All maleImproved group: 33.8 (5.6); not-improved group: 29.6 (5.1)No details on sport6Assessed 1–9 month/s postinjury
Keightley et al (2014)31 Cross-sectionalfMRIChildren's hospital (Canada)157M:8F14.5 (2.3)Soccer, football, swimming, other15Assessed 9–90 days postinjury
Bartnik-Olson et al (2014)32 Cross-sectionalMRI/MRSUniversity-based medical centre (USA)1512M:3F14.8 (2.8)Football, soccer, softball15Average time from injury=5.8 (SD 4.8) months
  • C/V, cervicogenic/vestibular; EEG, electroencephalogram; F, female; fMRI, functional MRI; M, male; MRS, magnetic resonance spectroscopy; n, number; PTM, post-traumatic migraine; SRC, sports-related concussion.

  • CBT, cognitive behavioural therapy; F, female; n, number; M, male; RCT, randomised controlled trial; SRC, sport-related concussion.