The Pediatric Emergency Care Applied Research Network (PECARN) algorithm for head injury is a clinical decision-making tool used in the pediatric population. It is specifically designed to assist healthcare providers in the emergency department to identify children at very low risk of clinically-important traumatic brain injuries (ciTBI) who do not require a computed tomography (CT) scan after head trauma. The PECARN algorithm stratifies risk based on factors such as the mechanism of injury, symptoms like vomiting and headache, and signs like loss of consciousness or not acting normally according to the parents. 

The clinical utility of the PECARN algorithm is to reduce unnecessary radiation exposure from CT scans in children with minor head injuries, while still accurately identifying those with significant injuries. 

The PECARN algorithm should not be used in children with severe mechanism of injury, such as a motor vehicle crash with ejection, death of another passenger, or rollover; a fall of more than 5 feet; or being hit by a high-impact object. It also should not be used in children with obvious signs of severe injury, such as a Glasgow Coma Scale (GCS) score of less than 15, signs of skull fracture, or altered mental status.

Pediatric Emergency Care Applied Research Network algorithm for head injury (PECARN algorithm)

# Criteria
 A. Altered mental status (+1)
B. Occipital or parietal or temporal scalp hematoma (+1)
C. Loss of consciousness >= 5 seconds (+1)
D. Severe mechanism of injury (+1)
E. Palpable or unclear skull fracture (+1)
F. Not acting normally per parent (+1)

# Conditions
- score == 0
- score >= 1