Pediatric Cervical Spine Injury Evaluation After Blunt Trauma: A Clinical Decision Analysis  Megan Hannon, MD, Rebekah Mannix, MD, MPH, Kate Dorney, MD, David Mooney, MD, Kara Hennelly, MD  Annals of Emergency Medicine  Volume 65, Issue 3, Pages 239-247 (March 2015) DOI: 10.1016/j.annemergmed.2014.09.002 Copyright © 2014 American College of Emergency Physicians Terms and Conditions

Figure 1 Decision analysis tree using 3 strategies for a hypothetical population of patients younger than 19 years and with blunt trauma: clinical stratification, screening radiographs followed by focused CT if the radiograph result was positive, and CT, each depicted as square decision nodes. After the initial choice, an outcome is observed of chance events (circles). Each branch ends at a possible terminal node (triangles). Utilities are listed at each terminal node. CSI, Cervical spine injury. Annals of Emergency Medicine 2015 65, 239-247DOI: (10.1016/j.annemergmed.2014.09.002) Copyright © 2014 American College of Emergency Physicians Terms and Conditions

Figure 2 Once the decision to image has been made, the choice of imaging modality is controversial. To represent the decision, the non-negligible CSI risk group was analyzed. The screening radiograph strategy was superior at a probability of CSI of 1.22% in this subgroup. To understand the effect of the p(CSINEXUSpos), 1-way sensitivity analysis was performed and identified 24.9% to be the p(CSINEXUSpos) at which above CT-all would be preferred. p(CSINEXUSpos), probability of CSI in the NEXUS-positive group. Annals of Emergency Medicine 2015 65, 239-247DOI: (10.1016/j.annemergmed.2014.09.002) Copyright © 2014 American College of Emergency Physicians Terms and Conditions

Figure 3 In the non-negligible CSI risk group, inputs with potential significant variability based on circumstance included both the probability of CSI (p[CSINEXUSpos]) and the radiation risk (probability of malignancy). A 2-way sensitivity analysis represented the effect of varying both the p(CSINEXUSpos) and the radiation risk probability of malignancy. As the probability of malignancy decreased or in scenarios suggesting the probability of CSI to be much higher than baseline tree inputs, CT strategy dominated. Annals of Emergency Medicine 2015 65, 239-247DOI: (10.1016/j.annemergmed.2014.09.002) Copyright © 2014 American College of Emergency Physicians Terms and Conditions