title: The recent downturn in utilization of CT: the start of a new trend?
abstract: OBJECTIVE
  The aim of this study was to examine recent CT utilization trends to ascertain if growth is still occurring.
  
  
  METHODS
  The nationwide Medicare Part B databases for 2000 through 2010 were used. All Current Procedural Terminology, fourth ed, codes for diagnostic CT (including CT angiography) were selected. Place-of-service codes were used to determine whether the studies were performed in inpatients, emergency department (ED) patients, hospital outpatient departments, or private offices. Utilization rates per 1,000 Medicare fee-for-service beneficiaries were calculated.
  
  
  RESULTS
  The total Medicare CT utilization rate increased each year from 325 per 1,000 in 2000 to 637 per 1,000 in 2009, representing a compound annual growth rate (CAGR) of 7.8%. But in 2010, the rate dropped for the first time, to 626 per 1,000 (-1.7%). For inpatient CT, the 2000 to 2009 CAGR was +5.5%, followed by a drop of 4.5% in 2010. For hospital outpatient department CT, the 2000 to 2009 CAGR was +5.1%, followed by a drop of 3.6% in 2010. For private office CT, the 2000 to 2009 CAGR was +11.3%, followed by a 7.8% drop in 2010. Emergency departments were the only location that saw continued growth, with a 2000 to 2009 CT CAGR of +15.2%, followed by another 8.4% increase in 2010.
  
  
  CONCLUSIONS
  After years of rapid growth, CT use in the Medicare population declined by 1.7% in 2010. The proportional decline was even greater among inpatients, hospital outpatient departments, and offices. The only place of service for which growth continued was emergency departments. Without the effect of emergency departments, the decline in 2010 would have been 4.7%. This downturn should help alleviate previous concerns about overly rapid CT growth.
authors.affiliation: Center for Research on Utilization of Imaging Services, Department of Radiology, Thomas Jefferson University Hospital and Jefferson Medical College, Philadelphia, Pennsylvania 19107, USA. david.levin@jeffersonhospital.org
authors.forename: David C
authors.initials: DC
authors.lastname: Levin
authors.forename: Vijay M
authors.initials: VM
authors.lastname: Rao
authors.forename: Laurence
authors.initials: L
authors.lastname: Parker
mesh_terms: D005544:Forecasting; D016345:Medicare Part B / Q000706:statistics & numerical data* / Q000639:trends*; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data* / Q000639:trends*; D014481:United States