Article Text

Download PDFPDF

Accuracy of NEXUS II head injury decision rule in children: a prospective PREDICT cohort study
  1. Franz E Babl1,2,3,
  2. Ed Oakley1,2,3,
  3. Stuart R Dalziel4,5,
  4. Meredith L Borland6,7,
  5. Natalie Phillips8,
  6. Amit Kochar9,
  7. Sarah Dalton10,
  8. John Alexander Cheek1,2,11,
  9. Yuri Gilhotra8,
  10. Jeremy Furyk12,
  11. Jocelyn Neutze13,
  12. Susan Donath2,3,
  13. Stephen Hearps2,
  14. Louise M Crowe2,
  15. Marta Arpone2,3,
  16. Silvia Bressan2,14,
  17. Mark D Lyttle2,15,16
  18. For the Paediatric Research in Emergency Department International Collaborative (PREDICT)
  1. 1 Emergency Department, Royal Children’s Hospital, Melbourne, Victoria, Australia
  2. 2 Murdoch Children’s Research Institute, Parkville, Victoria, Australia
  3. 3 Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia
  4. 4 Emergency Department, Starship Children’s Health, Auckland, New Zealand
  5. 5 Liggins Institute, University of Auckland, Auckland, New Zealand
  6. 6 Emergency Department, Princess Margaret Hospital for Children, Perth, Western Australia, Australia
  7. 7 Schools of Medicine, University of Western Australia, Crawley, Western Australia, Australia
  8. 8 Emergency Department, Lady Cilento Children’s Hospital, Brisbane and Child Health Research Centre, School of Medicine, The University of Queensland, South Brisbane, Queensland, Australia
  9. 9 Emergency Department, Women’s and Children’s Hospital Adelaide, North Adelaide, South Australia, Australia
  10. 10 Emergency Department, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia
  11. 11 Emergency Department, Monash Children’s Hospital, Parkville, Victoria, Australia
  12. 12 Emergency Department, Townsville Hospital, Townsville, Queensland, Australia
  13. 13 Emergency Department, Kidzfirst Middlemore Hospital, Auckland, New Zealand
  14. 14 Department of Women’s and Child’s Health, University of Padova, Padova, Italy
  15. 15 Academic Department of Emergency Care, University of the West of England, Bristol, UK
  16. 16 Emergency Department, Bristol Royal Children’s Hospital, Bristol, UK
  1. Correspondence to Dr Franz E Babl, Emergency Department, Royal Children’s Hospital, Parkville VIC 3052, Australia; franz.babl{at}


Objective The National Emergency X-Radiography Utilisation Study II (NEXUS II) clinical decision rule (CDR) can be used to optimise the use of CT in children with head trauma. We set out to externally validate this CDR in a large cohort.

Methods We performed a prospective observational study of patients aged <18 years presenting with head trauma of any severity to 10 Australian/New Zealand EDs. In a planned secondary analysis, we assessed the accuracy of the NEXUS II CDR (with 95% CI) to detect clinically important intracranial injury (ICI). We also assessed clinician accuracy without the rule.

Results Of 20 137 total patients, we excluded 28 with suspected penetrating injury. Median age was 4.2 years. CTs were obtained in ED for 1962 (9.8%), of whom 377 (19.2%) had ICI as defined by NEXUS II. 74 (19.6% of ICI) patients underwent neurosurgery.

Sensitivity for ICI based on the NEXUS II CDR was 379/383 (99.0 (95% CI 97.3% to 99.7%)) and specificity was 9320/19 726 (47.2% (95% CI 46.5% to 47.9%)) for the total cohort. Sensitivity in the CT-only cohort was similar. Of the 18 022 children without CT in ED, 49.4% had at least one NEXUS II risk criterion. Sensitivity for ICI by the clinicians without the rule was 377/377 (100.0% (95% CI 99.0% to 100.0%)) and specificity was 18 147/19 732 (92.0% (95% CI 91.6% to 92.3%)).

Conclusions NEXUS II had high sensitivity, similar to the derivation study. However, approximately half of unimaged patients were positive for NEXUS II risk criteria; this may result in an increased CT rate in a setting with high clinician accuracy.

  • trauma, head
  • emergency departments
  • imaging, ct/mri
  • paediatrics, paediatric emergency medicine

Statistics from


  • Contributors FEB: conceived the study, obtained grant funding, designed the study, provided overall supervision, interpreted the data, wrote the initial draft of the paper, gave final approval to be published and agreed to be accountable for all aspects of the work. MLB, NP, AK, SD, JAC, YG, JF, JN, MDL, MA, SH, SB, LMC, EO, SRD: designed the study, obtained the data, provided supervision, interpreted the data, drafted or revised it critically, gave final approval to be published and agreed to be accountable for all aspects of the work. SD: designed the study, supervised the analysis of the data, contributed to the interpretation of the data, revised the paper critically, gave final approval to be published and agreed to be accountable for all aspects of the work.

  • Funding The study was funded by grants from the National Health and Medical Research Council (project grant GNT1046727, Centre of Research Excellence for Paediatric Emergency Medicine GNT1058560), Canberra, Australia; the Murdoch Childrens Research Institute, Melbourne, Australia; the Emergency Medicine Foundation (EMPJ-11162), Brisbane, Australia; Perpetual Philanthropic Services (2012/1140), Australia; Auckland Medical Research Foundation (No. 3112011) and the A + Trust (Auckland District Health Board), Auckland, New Zealand; WA Health Targeted Research Funds 2013, Perth, Australia; the Townsville Hospital and Health Service Private Practice Research and Education Trust Fund, Townsville, Australia and supported by the Victorian Government’s Infrastructure Support Program, Melbourne, Australia. FEB’s time was part funded by a grant from the Royal Children’s Hospital Foundation, Melbourne, Australia, an NHMRC Practitioner Fellowship GNT1124466 and a Melbourne Children’s Clinician Scientist Fellowship. SRD’s time was part funded by the Health Research Council of New Zealand (HRC13/556).

  • Competing interests None declared.

  • Patient consent Not required.

  • Ethics approval The study was approved by the Royal Children’s Hospital, Melbourne, Australia.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement There are no additional data available.

  • Press Release Yes.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Linked Articles