title: Accuracy of the Canadian C-spine rule and NEXUS to screen for clinically important cervical spine injury in patients following blunt trauma: a systematic review.
abstract: BACKGROUND
  There is uncertainty about the optimal approach to screen for clinically important cervical spine (C-spine) injury following blunt trauma. We conducted a systematic review to investigate the diagnostic accuracy of the Canadian C-spine rule and the National Emergency X-Radiography Utilization Study (NEXUS) criteria, 2 rules that are available to assist emergency physicians to assess the need for cervical spine imaging.
  
  
  METHODS
  We identified studies by an electronic search of CINAHL, Embase and MEDLINE. We included articles that reported on a cohort of patients who experienced blunt trauma and for whom clinically important cervical spine injury detectable by diagnostic imaging was the differential diagnosis; evaluated the diagnostic accuracy of the Canadian C-spine rule or NEXUS or both; and used an adequate reference standard. We assessed the methodologic quality using the Quality Assessment of Diagnostic Accuracy Studies criteria. We used the extracted data to calculate sensitivity, specificity, likelihood ratios and post-test probabilities.
  
  
  RESULTS
  We included 15 studies of modest methodologic quality. For the Canadian C-spine rule, sensitivity ranged from 0.90 to 1.00 and specificity ranged from 0.01 to 0.77. For NEXUS, sensitivity ranged from 0.83 to 1.00 and specificity ranged from 0.02 to 0.46. One study directly compared the accuracy of these 2 rules using the same cohort and found that the Canadian C-spine rule had better accuracy. For both rules, a negative test was more informative for reducing the probability of a clinically important cervical spine injury.
  
  
  CONCLUSIONS
  Based on studies with modest methodologic quality and only one direct comparison, we found that the Canadian C-spine rule appears to have better diagnostic accuracy than the NEXUS criteria. Future studies need to follow rigorous methodologic procedures to ensure that the findings are as free of bias as possible.
authors.affiliation: The University of Sydney, Sydney, Australia. zmichaleff@georgeinstitute.org.au
authors.forename: Zoe A
authors.initials: ZA
authors.lastname: Michaleff
authors.forename: Chris G
authors.initials: CG
authors.lastname: Maher
authors.forename: Arianne P
authors.initials: AP
authors.lastname: Verhagen
authors.forename: Trudy
authors.initials: T
authors.lastname: Rebbeck
authors.forename: Chung-Wei Christine
authors.initials: CW
authors.lastname: Lin
mesh_terms: D000465:Algorithms; D001315:Australia; D002170:Canada; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000293:injuries; D004635:Emergency Medicine / Q000592:standards; D004636:Emergency Service, Hospital / Q000592:standards*; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D019838:Neck Injuries / Q000175:diagnosis / Q000000981:diagnostic imaging*; D020380:Needs Assessment; D012680:Sensitivity and Specificity; D013124:Spinal Injuries / Q000175:diagnosis / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000592:standards* / Q000706:statistics & numerical data; D014949:Wounds, Nonpenetrating / Q000175:diagnosis / Q000000981:diagnostic imaging*