About the PECARN head trauma rule
PECARN (Pediatric Emergency Care Applied Research Network) derived and validated a clinical decision rule for children who present with minor blunt head trauma and a Glasgow Coma Scale of 14 or 15. Published by Kuppermann and colleagues in 2009 from more than 42,000 children across 25 emergency departments, it remains the most widely cited pediatric head-injury rule and is built into many emergency-department order sets. It does not produce a single numeric score - instead it sorts a child into one of three risk categories using two separate, age-specific checklists.
How the rule is built
There are two algorithms, chosen by the child's age:
- Under 2 years: high risk is GCS 14 or below, altered mental status, or a palpable skull fracture. Without those, intermediate risk is an occipital, parietal, or temporal scalp hematoma; loss of consciousness of 5 seconds or more; a severe injury mechanism; or a caregiver report that the child is not acting normally.
- 2 to 18 years: high risk is GCS 14 or below, altered mental status, or signs of a basilar skull fracture. Without those, intermediate risk is any loss of consciousness, a history of vomiting, a severe injury mechanism, or a severe headache.
In both bands, a severe mechanism means a motor-vehicle crash with patient ejection, death of another passenger, or rollover; a pedestrian or unhelmeted cyclist struck by a motor vehicle; a fall of more than about 3 feet (under 2 years) or 5 feet (2 years and older); or the head struck by a high-impact object. A child with none of the high- or intermediate-risk findings falls into the very-low-risk group.
Interpreting the result
High risk carries roughly a 4.3-4.4% risk of clinically-important traumatic brain injury (ciTBI) in the validation cohort, and CT imaging is recommended. Intermediate risk carries roughly a 0.9% risk, and PECARN supports either CT or a period of observation, guided by shared decision-making between the clinician and caregiver. Very low risk carries a risk below 0.02% (under 2 years) or 0.05% (2 years and older), and CT is not routinely recommended. These figures are group averages from the derivation and validation study, not a guarantee for any individual child.
When to consult a professional
This tool performs the standard PECARN classification for education and documentation. It does not replace direct clinical evaluation, and the decision to image, observe, or discharge a child should always rest with the treating clinician, who weighs the rule alongside the full history, exam, and caregiver judgment.