Back to all tools

PECARN Pediatric Head Injury Rule

Age-specific CT risk stratification for children with minor blunt head trauma. Select the age group, check applicable predictors, and review the recommended risk tier.

Applicability

Use forAge <18, blunt head trauma, within 24 hours.
BaselineMinor head trauma with GCS 14-15.
GoalIdentify children where CT can usually be avoided.

Age Branch

Younger Than 2 Years

Use the infant/toddler branch for children younger than 2 years with minor blunt head trauma.

High-Risk Predictors

Observation vs CT Predictors

CT Not Routinely Indicated
No PECARN predictors selected.
Very low risk
Age branchYounger than 2 years
Risk tierVery low risk
DecisionCT generally not indicated by PECARN.
Next stepContinue clinical assessment and provide return precautions if discharged.
High-risk predictorHead CT is generally recommended.
Intermediate predictor onlyObservation vs CT using clinical judgment.
No predictorsCT is generally not indicated by PECARN.

Disclaimer: For educational purposes only. Not a substitute for clinical judgment. Pediatric head trauma decisions should consider the full clinical context, local protocols, and caregiver discussion.

About This Tool

What Is PECARN?

The PECARN pediatric head injury rule was derived and validated by the Pediatric Emergency Care Applied Research Network to identify children at very low risk of clinically important traumatic brain injury after minor blunt head trauma. It separates children younger than 2 years from those 2 years or older because symptoms and exam findings differ by age.

Interpretation

High-risk predictors generally support head CT because the risk of clinically important traumatic brain injury is higher. Intermediate predictors support observation versus CT, depending on symptom progression, multiple findings, clinician experience, parental preference, and local practice. No PECARN predictors indicates very low risk, and CT can usually be avoided.

Clinical Pearls

  • PECARN is designed for minor blunt head trauma, not all altered children and not penetrating injury.
  • For children younger than 3 months, clinicians often have a lower threshold for observation or imaging even when criteria appear reassuring.
  • Observation is an active strategy: reassess mental status, vomiting, headache, caregiver concern, and overall trajectory.
  • Record the age branch used and the specific predictors present, not just "PECARN positive."

References

  1. Kuppermann N, Holmes JF, Dayan PS, et al; Pediatric Emergency Care Applied Research Network. Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet. 2009;374(9696):1160-1170.
  2. Nigrovic LE, Lee LK, Hoyle J, et al. Prevalence of clinically important traumatic brain injuries in children with minor blunt head trauma and isolated severe injury mechanisms. Arch Pediatr Adolesc Med. 2012;166(4):356-361.
  3. Babl FE, Borland ML, Phillips N, et al. Accuracy of PECARN, CATCH, and CHALICE head injury decision rules in children: a prospective cohort study. Lancet. 2017;389(10087):2393-2402.

Formula last verified: May 2026