Abstract: Three cohort studies were eligible for analysis, including 3380 patients ; 96 children were diagnosed with CSI. One study evaluated the accuracy of the Canadian C-spine Rule and the NEXUS criteria, and two studies evaluated the accuracy of the NEXUS criteria. The studies were of moderate quality. Due to the small number of included studies and the diverse outcomes of those studies, we could not describe a pooled estimate for the diagnostic test accuracy. The sensitivity of the NEXUS criteria of the individual studies was 0.57 (95% confidence interval (CI) 0.18 to 0.90), 0.98 (95% CI 0.91 to 1.00) and 1.00 (95% CI 0.88 to 1.00). The specificity of the NEXUS criteria was 0.35 (95% CI 0.25 to 0.45), 0.54 (95% CI 0.45 to 0.62) and 0.2 (95% CI 0.18 to 0.21). For the Canadian C-spine Rule the sensitivity was 0.86 (95% CI 0.42 to 1.00) and specificity was 0.15 (95% CI 0.08 to 0.23). Since the quantity of the data was small we were not able to investigate heterogeneity. There are currently few studies assessing the diagnostic test accuracy of the NEXUS criteria and CCR in children. At the moment, there is not enough evidence to determine the accuracy of the Canadian C-spine Rule to detect CSI in pediatric trauma patients following blunt trauma. The confidence interval of the sensitivity of the NEXUS criteria between the individual studies showed a wide range, with a lower limit varying from 0.18 to 0.91 with a total of four false negative test results, meaning that if physicians use the NEXUS criteria in children, there is a chance of missing CSI. Since missing CSI could have severe consequences with the risk of significant morbidity, we consider that the NEXUS criteria are at best a guide to clinical assessment, with current evidence not supporting strict or protocolized adoption of the tool into pediatric trauma care. Moreover, we have to keep in mind that the sensitivity differs among several studies, and individual confidence intervals of these studies show a wide range. Our main conclusion is therefore that additional well-designed studies with large sample sizes are required to better evaluate the accuracy of the NEXUS criteria or the Canadian C-spine Rule, or both, in order to determine whether they are appropriate triage tools for the clearance of the cervical spine in children following blunt trauma.

Plain-language summary: We searched medical literature databases to identify studies which tested how well both decision tools can establish whether children are at risk for CSI after blunt trauma. We performed the search in February 2015. We identified three studies of moderate to good quality. All studies tested the accuracy of the NEXUS criteria, and one of them also tested the accuracy of the Canadian C-spine Rules. Since only one study looked at the accuracy of the Canadian C-spine Rules, there is not enough evidence at the moment to determine whether the Canadian C-spine Rules can be used safely in children. The sensitivity and specificity of the NEXUS criteria varied among the three studies, meaning that there is a chance of false-negative test results when using the NEXUS criteria, and as a result there is a chance of missing cervical spine injury if doctors only rely on the NEXUS criteria. We therefore consider that the NEXUS criteria are at best a guide to clinical assessment, with current evidence not supporting strict or protocolized adoption of the tool into pediatric trauma care. The conclusion of our review is that we need more research to evaluate the accuracy of the NEXUS criteria and the Canadian C-spine rules for routine use in children.