Use only for minor head injury with GCS 13–15 and witnessed loss of consciousness, amnesia, or confusion — and none of the rule's exclusions (age < 16, anticoagulation, seizure after injury, etc.).
GCS below 15 at 2 hours after injury
Suspected open or depressed skull fracture
Any sign of basal skull fracture
Two or more episodes of vomiting
Age 65 or older
Retrograde amnesia ≥ 30 minutes before impact
Dangerous mechanism (pedestrian struck, ejected, fall > 3 ft / 5 stairs)
Evidence
Original publication
Stiell IG, Wells GA, Vandemheen K, et al. The Canadian CT Head Rule for patients with minor head injury. 100% sensitive for neurosurgical intervention and 98–100% for clinically important brain injury in the derivation set.
The Lancet, 2001
Open source
Validation
Stiell IG, Clement CM, Rowe BH, et al. Comparison of the Canadian CT Head Rule and the New Orleans Criteria in patients with minor head injury. Prospective multicentre comparison; the CCHR retained high sensitivity with greater specificity.
JAMA, 2005
Open source
Last reviewed: 2026-09
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MedScore is an educational and clinical decision-support tool. It does not provide a diagnosis, a treatment, or a drug-dosing recommendation, and it does not replace clinical judgement or local guidelines. Confirm every result against the original source before acting on it. The treating clinician remains responsible for all decisions.