Concussion and head injury in sport: assessment and return to play

The current international consensus on prevention, diagnosis and management of sport-related concussion; introduces SCAT6 and CRT6.

• Diagnosis rests on a multimodal, serial assessment (SCAT6 and Child SCAT6 acutely, the SCOAT6 office tool in the days after), not a single test or biomarker.
• Introduces a staged return-to-sport and return-to-learn strategy, with early, light aerobic activity within 24 to 48 hours rather than strict rest.
• Broadens scope to the para athlete, the athlete's perspective, ethics, retirement decisions and the possible long-term neurological effects of repeated head impacts.

Our appraisal: The current international reference standard, built from commissioned systematic reviews layered on expert consensus; it standardises language and pathways but still leans on clinical judgement, since no single tool or blood biomarker yet rules concussion in or out. Treat its return-to-sport stages as a scaffold, not validated pass-or-fail thresholds.

ACL-specific consensus defining return to sport as a criteria-based continuum rather than a time point, and setting out testing and shared decision-making for clearance after ACL injury.

• Return to sport is a criteria-based continuum, return to participation, then return to sport, then return to performance, not a single date.
• Clearance should rest on objective testing (strength, hop, movement quality, psychological readiness), not time since surgery alone.
• The decision is shared between clinician and athlete, accounting for the sport's demands and the athlete's risk tolerance.

Our appraisal: Consensus via modified Delphi, so it sets the decision framework rather than validating any single test battery or cut-off. It is most useful as a reminder that a passed clock is not a passed knee; the specific thresholds still lack strong prospective validation.

The fifth international consensus on sport-related concussion, now superseded by Amsterdam 2023 but the origin of the SCAT5, the Child SCAT5 and the graded return-to-sport strategy still in wide use.

• Established the six-stage graded return-to-sport progression, advancing only when the athlete tolerates each step.
• Introduced the SCAT5 and Child SCAT5 for sideline and office assessment, and moved away from mandatory prolonged rest.
• Recommended removal from play with any suspected concussion, with no same-day return to play.

Our appraisal: Now superseded by the 2023 Amsterdam statement, so cite it for historical context or where SCAT5-era tools remain in local protocols. Like all Concussion in Sport Group statements it is expert consensus informed by systematic review, so its graded progression is a pragmatic framework rather than a validated timetable.

Defines and operationalises 'return to sport' as a continuum (return to participation, return to sport, return to performance), with a shared decision-making framework (StARRT).

• Operationalises return to sport as a three-stage continuum applicable across injuries, not just ACL.
• Introduces the StARRT framework (Strategic Assessment of Risk and Risk Tolerance) for the return decision.
• Frames clearance as shared decision-making under uncertainty rather than a purely biological milestone.

Our appraisal: A foundational framework paper rather than an evidence synthesis. Its strength is a shared language for the return-to-sport decision: it tells you how to structure the decision, not what the pass criteria are, so pair it with injury-specific testing evidence.