PECARN (Pediatric Emergency Care Applied Research Network) created a pair of validated clinical decision rules to help clinicians identify children with minor blunt head trauma who are at very low risk of clinically-important traumatic brain injury (ciTBI)—and therefore are unlikely to benefit from CT imaging.
Who it’s for
PECARN applies to children and adolescents <18 years who present within 24 hours of blunt head trauma and have GCS 14–15.
Why it matters
Head CT can be lifesaving when indicated, but it also exposes children to ionizing radiation. PECARN helps reduce unnecessary CT while maintaining high sensitivity for clinically important injuries.
Two age-specific rules
PECARN uses different predictors for:
- < 2 years
- ≥ 2 years
This is because symptoms and exam findings differ in infants/toddlers vs older children.
Core predictors (summary)
Age < 2 years – predictors (6):
- Altered mental status / GCS 14
- Palpable skull fracture
- Non-frontal scalp hematoma
- Loss of consciousness ≥ 5 seconds
- Severe mechanism of injury
- Not acting normally per parent
Age ≥ 2 years – predictors (6):
- Altered mental status / GCS 14
- Signs of basilar skull fracture
- Any loss of consciousness
- Vomiting
- Severe headache
- Severe mechanism of injury
Severe mechanism (PECARN examples) commonly include: MVC with ejection/rollover/death of another passenger; pedestrian/bicyclist without helmet struck by motor vehicle; significant fall height; head struck by high-impact object.
How results are typically interpreted
PECARN is not a “score” so much as a risk stratification rule:
- High risk (e.g., skull fracture signs or altered mental status): ciTBI risk >4% → CT generally recommended.
- Intermediate risk (other predictors without high-risk signs): ciTBI risk about 0.9% → observation vs CT based on clinical factors.
- Very low risk (no predictors): ciTBI risk <0.02% for <2 years, <0.05% for ≥2 years → CT typically not indicated.
Clinical note: National guidance also emphasizes not routinely imaging pediatric mTBI/concussion and using validated decision rules to guide imaging decisions.
PECARN Pediatric Head Injury / Trauma Calculator
For minor blunt head trauma presenting within 24 hours, typically GCS 14–15. Use alongside clinical judgment and local protocol.
Reminder: Consider other red flags / exclusions (e.g., anticoagulation, suspected abuse, penetrating trauma, focal neuro deficits, clinician concern). PECARN supports decision-making; it does not replace a full clinical assessment.
