title: Variability in imaging utilization in U.S. pediatric hospitals.
abstract: BACKGROUND
  Use of medical imaging is under scrutiny because of rising costs and radiation exposure. We compare imaging utilization and costs across pediatric hospitals to determine their variability and potential determinants.
  
  
  METHODS
  Data were extracted from the Pediatric Health Information System (PHIS) database for all inpatient encounters from 40 U.S. children's hospitals. Imaging utilization and costs were compared by insurance type, geographical region, hospital size, severity of illness, length of stay and type of imaging, all among specific diagnoses.
  
  
  RESULTS
  The hospital with the highest utilization performed more than twice as many imaging studies per patient as the hospital with the lowest utilization. Similarly, imaging costs ranged from $154 to $671/patient. Median imaging-utilization rate was 1.7 exams/patient on the ward and increased significantly in the PICU (11.8 exams/patient) and in the NICU (17.7 exams per patient, (P < 0.001). Considerable variability in imaging utilization persisted despite adjustment for case mix index (CMI, range in variation 16.6-25%). We found a significant correlation between imaging utilization and both CMI and length of stay, P < 0.0001). However, only 36% of the variation in imaging utilization could be explained by CMI.
  
  
  CONCLUSIONS
  Diagnostic imaging utilization and costs vary widely in pediatric hospitals.
authors.affiliation: Department of Radiology, Children's Hospital Boston, 300 Longwood Ave., Boston, MA 02115, USA.
authors.forename: Ryan W
authors.initials: RW
authors.lastname: Arnold
authors.forename: Dionne A
authors.initials: DA
authors.lastname: Graham
authors.forename: Patrice R
authors.initials: PR
authors.lastname: Melvin
authors.forename: George A
authors.initials: GA
authors.lastname: Taylor
mesh_terms: D016208:Databases, Factual; D003952:Diagnostic Imaging / Q000191:economics / Q000706:statistics & numerical data*; D006776:Hospitals, Pediatric / Q000706:statistics & numerical data*; D006801:Humans; D007348:Insurance, Health / Q000706:statistics & numerical data; D007902:Length of Stay / Q000706:statistics & numerical data; D016014:Linear Models; D012720:Severity of Illness Index; D014481:United States