title: Inpatient imaging utilization: trends of the past decade.
abstract: OBJECTIVE
  We have previously reported inpatient imaging utilization trends at our institution from fiscal year (FY) 1984 through FY 2002. In this study, we assessed the trends in imaging utilization for inpatients from FY 2003 through FY 2012.
  
  
  METHODS
  In this institutional review board-approved retrospective study performed at a 793-bed tertiary care academic institution, we reviewed imaging utilization in adult inpatients from October 1, 2002, through September 30, 2012 (FY 2003 through FY 2012), and recorded the gross number of imaging studies coded by modality (conventional [radiography and fluoroscopy], ultrasound, nuclear medicine, CT, and MRI) and associated relative value units (RVUs). We used linear regression to assess trends in number of imaging studies and RVUs per case-mix-adjusted admission (CMAA).
  
  
  RESULTS
  The total number of imaging studies, as well as the number of CT, nuclear medicine, and conventional studies adjusted for case mix, decreased (p=0.02, p=0.0006, p=0.0008, and p=0.001, respectively); CT per CMAA increased until FY 2009 and then decreased through FY 2012. Utilization of ultrasound and MRI did not change significantly (p=0.15 and p=0.22, respectively). Unadjusted global RVUs increased until FY 2009 and then showed a slight decrease through FY 2012 (p=0.04), whereas RVUs per CMAA did not change significantly (p=0.18).
  
  
  CONCLUSIONS
  After decades of continued rise, imaging utilization for inpatients significantly decreased by most measures between FY 2009 and FY 2012. Future studies to evaluate the contribution of various factors to this decline, including efforts to reduce inappropriate use of imaging and concerns about potential harms of radiation exposure, may be helpful in optimizing imaging utilization and resource planning.
authors.affiliation: 1 Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA.
authors.forename: Atul B
authors.initials: AB
authors.lastname: Shinagare
authors.forename: Ivan K
authors.initials: IK
authors.lastname: Ip
authors.forename: Sarah K
authors.initials: SK
authors.lastname: Abbett
authors.forename: Richard
authors.initials: R
authors.lastname: Hanson
authors.forename: Steven E
authors.initials: SE
authors.lastname: Seltzer
authors.forename: Ramin
authors.initials: R
authors.lastname: Khorasani
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001900:Boston / Q000453:epidemiology; D003952:Diagnostic Imaging / Q000706:statistics & numerical data* / Q000639:trends*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data* / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data* / Q000639:trends*; D014600:Utilization Review; D055815:Young Adult