title: Use of emergency department imaging in patients with minor trauma.
abstract: Advanced radiographic studies have detrimental risks, yet the prevalence of CT utilization in patients with minor trauma presenting to the emergency department (ED) has never been fully evaluated. Our objective was to evaluate the frequency of CT imaging in patients presenting to the ED for minor trauma.
  
  
  
  A retrospective analysis of the California Office of Statewide Health Planning and Development Emergency Department and Ambulatory Surgery Data from 2005 to 2013 was performed. A total of 8,535,831 patients were identified using the following inclusion criteria: adult patients (age ≥18 y); with a traumatic ECODE diagnosis and injury severity score <9; and discharge to home. The primary study outcome measurement was the prevalence of CT imaging for each year in the study period. We performed univariate and multivariate analysis to evaluate clinical and hospital-level factors related to CT use in this population. We also performed a trend analysis using Poisson logistic regression to assess the trend of imaging scans over the study period.
  
  
  
  Of the study population, 5.9% received at least one CT study during their ED visit. The proportion of patients with at least one CT scan increased from 3.51% in 2005 to 7.17% in 2013 (P < 0.005). Adjusted predictors for CT included age 18-24 y or >45 y (P < 0.005), Medicare and self-pay patients (P < 0.005), fall injuries (P < 0.005), motor vehicle collision injuries (P < 0.005), and patients seen at level I/II trauma centers (P = 0.005).
  
  
  
  Even after clinical and demographic predictors were adjusted for, there was a 1.97-fold increase in CT among minor trauma patients from 2005-2013.
authors.affiliation: Department of Emergency Medicine, University of California, San Francisco, California.
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Tong
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, California.
authors.forename: Kristan
authors.initials: K
authors.lastname: Staudenmayer
authors.affiliation: Department of Epidemiology and Biostatistics, University of California, San Francisco, California.
authors.forename: Feng
authors.initials: F
authors.lastname: Lin
authors.affiliation: Department of Emergency Medicine and Philip R. Lee Institute for Health Policy Studies, University of California, San Francisco, California. Electronic address: renee.hsia@ucsf.edu.
authors.forename: Renee Y
authors.initials: RY
authors.lastname: Hsia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002140:California; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016012:Poisson Distribution; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*; D014947:Wounds and Injuries / Q000000981:diagnostic imaging*; D055815:Young Adult
keywords: Computed tomography; Emergency department; Minor trauma