Emergency Radiology

, Volume 22, Issue 5, pp 511–516 | Cite as

Clinical scoring system may improve yield of head CT of non-trauma emergency department patients

  • Christopher Bent
  • Paul S. Lee
  • Peter Y. Shen
  • Heejung Bang
  • Mathew Bobinski
Original Article


The positive rate of head CT in non-trauma patients presenting to the emergency department (ED) is low. Currently, indications for imaging are based on the individual experience of the treating physician, which contributes to overutilization and variability in imaging utilization. The goals of this study are to ascertain the predictors of positive head CT in non-trauma patients and demonstrate feasibility of a clinical scoring algorithm to improve yield. We retrospectively reviewed 500 consecutive ED non-trauma patients evaluated with non-contrast head CT after presenting with headache, altered mentation, syncope, dizziness, or focal neurologic deficit. Medical records were assessed for clinical risk factors: focal neurologic deficit, altered mental status, nausea/vomiting, known malignancy, coagulopathy, and age. Data was analyzed using logistic regression and receiver operator characteristic (ROC) curves and three derived algorithms. Positive CTs were found in 51 of 500 patients (10.2 %). Only two clinical factors were significant: focal neurologic deficit (adjusted odds ratio (OR) 20.7; 95 % confidence interval (CI) 9.4–45.7) and age >55 (adjusted OR 3.08; CI 1.44–6.56). Area under the ROC curve for all three algorithms was 0.73–0.83. In proposed algorithm C, only patients with focal neurologic deficit (major risk factor) or ≥2 of the five minor risk factors (altered mental status, nausea/vomiting, known malignancy, coagulopathy, and age) would undergo CT imaging. This may reduce utilization by 34 % with only a small decrease in sensitivity (98 %). Our simple scoring algorithm utilizing multiple clinical risk factors could help to predict the non-trauma patients who will benefit from CT imaging, resulting in reduced radiation exposure without sacrificing sensitivity.


Computed tomography (CT) Emergency department (ED) Utilization Actionable results Clinical risk factors 



Odds ratio


Area under curve


Computed tomography


Emergency department


Electronic medical records


Posterior reversible encephalopathy syndrome



We thank John Brock for his assistance in the preparation of this manuscript.

Conflict of interest

The authors declare that they have no conflict of interest.

Financial support

This project was partly supported by the National Center for Advancing Translational Sciences, National Institutes of Health, through grant number UL1 TR000002.


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Copyright information

© American Society of Emergency Radiology 2015

Authors and Affiliations

  • Christopher Bent
    • 1
  • Paul S. Lee
    • 1
  • Peter Y. Shen
    • 1
  • Heejung Bang
    • 2
  • Mathew Bobinski
    • 1
  1. 1.Department of Diagnostic Radiology, Section of NeuroradiologyUniversity of California, Davis School of MedicineSacramentoUSA
  2. 2.Department of Public Health Sciences, Division of BiostatisticsUniversity of California, Davis School of MedicineSacramentoUSA

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