Neurology · Emergency Medicine
CHIP (CT in Head Injury Patients) Prediction Rule
Predicts intracranial traumatic CT findings in patients with minor blunt head trauma.
Use only within the rule’s intended population
Adults aged 16 years or older presenting within 24 hours of blunt head trauma, with an initial GCS of 13–15. Do not use this calculator as a substitute for clinical judgment or local head-injury guidance.
Clinical criteria
Complete every field. The original simple CHIP rule classifies criteria as major or minor rather than producing a single numeric score.
How the rule is interpreted
| Classification | CHIP recommendation |
|---|---|
| At least 1 major criterion | Head CT indicated |
| No major criteria and at least 2 minor criteria | Head CT indicated |
| No major criteria and 0–1 minor criterion | Low risk by the simple CHIP rule; CT is not indicated by this rule alone |
Important limitations
- This page implements the original simple CHIP prediction rule, not the later updated CHIP model.
- It is not validated for patients younger than 16 years, penetrating head trauma, or initial GCS outside 13–15.
- Clinical decision rules support—but do not replace—assessment, observation, local guidance, or senior review.
Reference
Smits M, Dippel DWJ, Steyerberg EW, et al. Predicting intracranial traumatic findings on computed tomography in patients with minor head injury: the CHIP prediction rule. Annals of Internal Medicine. 2007;146(6):397–405. doi:10.7326/0003-4819-146-6-200703200-00004.
