PECARN calculator

PECARN Pediatric Head Injury

PECARN — Pediatric Head CT Decision Rule

Age Group	Select One
Patient Age	1 <2 years    ≥2 years

Age <2 Years — Risk Factors

Criteria	No	Yes
GCS <15 (altered mental status)	1
Palpable skull fracture	1
Occipital/parietal/temporal scalp hematoma	1
Loss of consciousness ≥5 seconds	1
Not acting normally per parent	1
Severe mechanism of injury (MVC with ejection/rollover/fatality, pedestrian/cyclist without helmet struck by motorized vehicle, fall >3 feet, head struck by high-impact object)	1
Risk Factors (<2y)	/ 6

Age ≥2 Years — Risk Factors

Criteria	No	Yes
GCS <15 (altered mental status)	1
Signs of basilar skull fracture (hemotympanum, raccoon eyes, Battle sign, CSF otorrhea/rhinorrhea)	1
Vomiting	1
Loss of consciousness	1
Severe headache	1
Severe mechanism of injury (MVC with ejection/rollover/fatality, pedestrian/cyclist without helmet struck by motorized vehicle, fall >5 feet, head struck by high-impact object)	1
Risk Factors (≥2y)	/ 6

Interpretation (for selected age group)
0	Very low risk — ciTBI risk <0.02% (<2y) or <0.05% (≥2y). CT not recommended.
1 (intermediate*)	Low risk — ciTBI risk ~0.9% (<2y) or ~0.8% (≥2y). Observation vs. CT. *Only if GCS=15 and no skull fracture/AMS. Consider observation for 4-6 hours.
GCS<15 or skull fx	High risk — ciTBI risk 4.4% (<2y) or 4.3% (≥2y). CT recommended.

References
Kuppermann N, Holmes JF, Dayan PS, et al. Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet. 2009;374:1160-1170. PMID 19758692.