Background: Thoracic injuries are a major cause of death associated with blunt trauma in children. Screening for injury with chest x-ray study, compared with chest computed tomography (CT) scan, has been controversial, weighing the benefits of specificity with the detriment of radiation exposure. Objective: To identify predictors of thoracic injury in children presenting as trauma activations to a Level I trauma center after blunt torso trauma, and to compare these predictors with those previously reported in the literature. Methods: We performed a retrospective chart review of pediatric patients (< 18 years of age) who presented to the Emergency Department of a Level I trauma center between June 2010 and June 2013 as a trauma activation after sustaining a blunt torso trauma and who received diagnostic imaging of the chest as part of their initial evaluation. Results: Data analysis was performed on 166 patients. There were 33 patients (20%) with 45 abnormalities detected on diagnostic imaging of the chest, with the most common abnormalities being lung contusion (36%), pneumothorax (22%), and rib fracture (13%). Statistically significant predictors of abnormal diagnostic imaging of the chest included Glasgow Coma Scale score (GCS) < 15 (27% with abnormality vs. 13% without abnormality), hypoxia (22% vs. 5%), syncope/loss of consciousness (55% vs. 35%), cervical spine tenderness (12% vs. 3%), thoraco-lumbar-sacral spine tenderness (41% vs. 17%), and abdominal/pelvic tenderness (12% vs. 3%). Conclusions: Based on our data, predictors of thoracic injury in children after blunt torso trauma include GCS < 15, hypoxia, syncope/dizziness, cervical spine tenderness, thoraco-lumbar-sacral spine tenderness, and abdominal/ pelvic tenderness. (C) 2016 Elsevier Inc. All rights reserved.