External Validation of the PECARN Head Trauma Prediction Rules in Japan

The Pediatric Emergency Care Applied Research Network (PECARN) head trauma prediction rules are used to assist computed tomography (CT) decision-making for children with minor head trauma. Although the PECARN rules have been validated in North America and Europe, they have not yet been validated in Asia. In Japan, there are no clinical decision rules for children with minor head trauma. The rate of head CT for children with minor head trauma in Japan is high since CT is widely accessible across the country. The objective of this study was to evaluate the diagnostic accuracy of the PECARN rules for identifying clinically important traumatic brain injuries (ciTBI) in children with minor head trauma in Japan.

We conducted a retrospective cohort study at a tertiary care pediatric hospital in Japan (30,000 patients/year). We enrolled all children younger than 18 years with minor head trauma (Glasgow Coma Scale ≥ 14) who presented to the emergency department within 24 hours of their injury between January and December 2013. We retrospectively classified the children into three risk categories according to the PECARN rules. The PECARN rules were considered negative when children were classified into the very-low-risk category. The primary outcome was considered positive when a child had ciTBI defined as head injury resulting in death, neurosurgery, intubation for > 24 hours, or hospital admission ≥ 2 nights with evidence of TBI on CT.

Among 2,208 children included in the study, 24 (1.1%) had ciTBI. Sensitivities and specificities of the PECARN rules to predict ciTBI were 85.7% (12/14; 95% confidence interval [CI] = 57.2 to 98.2) and 73.5% (572/778; 95% CI = 70.3 to 76.6), respectively, for children < 2 years old, and 100% (10/10; 95% CI = 58.7 to 100) and 73.5% (1033/1406; 95% CI = 71.0 to 75.7) for children ≥ 2 years old, respectively. There were 10 cases of physically abused children < 2 years old, and six (60%) of them had ciTBI. Also, two cases of physically abused children with ciTBI were classified as very low risk. If we did not include physically abused children, the sensitivity of the PECARN rule for children < 2 years old improved from 85.7% to 100% (8/8).

The PECARN rules were less sensitive for physically abused children, although the rules showed excellent applicability for the cohort without physical abuse. Thoughtful consideration may be needed for cases of nonaccidental trauma. Further prospective studies are required to verify the applicability of the PECARN rules for children with minor head trauma in Japan.