Emergency Medicine

Canadian CT Head Rule

Whether CT is needed after minor head injury.

Education and reference only. Not a substitute for clinical judgement, local policy or product labelling. Always verify before clinical use. Values are calculated in your browser and never stored.

When to use

Use in minor head injury (GCS 13–15, witnessed LOC/amnesia/disorientation) to decide whether CT is needed. If NO criteria are present, CT can generally be avoided. NOT for anticoagulated patients, seizure, or age <16.

Why use

It safely reduces CT imaging after minor head injury.

Critical actions

Applies only to minor head injury meeting the inclusion criteria. It does NOT apply to patients on anticoagulants, with bleeding disorders, or post-seizure — image per local policy.

Evidence & references

  1. Stiell IG et al. The Canadian CT Head Rule for patients with minor head injury. Lancet. 2001.

About the creator

Stiell IG et al.

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