title: Prostate cancer imaging trends after a nationwide effort to discourage inappropriate prostate cancer imaging.
abstract: BACKGROUND
  Reducing inappropriate use of imaging to stage incident prostate cancer is a challenging problem highlighted recently as a Physician Quality Reporting System quality measure and by the American Society of Clinical Oncology and the American Urological Association in the Choosing Wisely campaign. Since 2000, the National Prostate Cancer Register (NPCR) of Sweden has led an effort to decrease national rates of inappropriate prostate cancer imaging by disseminating utilization data along with the latest imaging guidelines to urologists in Sweden. We sought to determine the temporal and regional effects of this effort on prostate cancer imaging rates.
  
  
  METHODS
  We performed a retrospective cohort study among men diagnosed with prostate cancer from the NPCR from 1998 to 2009 (n = 99 879). We analyzed imaging use over time stratified by clinical risk category (low, intermediate, high) and geographic region. Generalized linear models with a logit link were used to test for time trend.
  
  
  RESULTS
  Thirty-six percent of men underwent imaging within 6 months of prostate cancer diagnosis. Overall, imaging use decreased over time, particularly in the low-risk category, among whom the imaging rate decreased from 45% to 3% (P < .001), but also in the high-risk category, among whom the rate decreased from 63% to 47% (P < .001). Despite substantial regional variation, all regions experienced clinically and statistically (P < .001) significant decreases in prostate cancer imaging.
  
  
  CONCLUSIONS
  A Swedish effort to provide data on prostate cancer imaging use and imaging guidelines to clinicians was associated with a reduction in inappropriate imaging over a 10-year period, as well as slightly decreased appropriate imaging in high-risk patients. These results may inform current efforts to promote guideline-concordant imaging in the United States and internationally.
authors.affiliation: US Department of Veterans Affairs, New York University, New York, NY, USA.
authors.forename: Danil V
authors.initials: DV
authors.lastname: Makarov
authors.forename: Stacy
authors.initials: S
authors.lastname: Loeb
authors.forename: David
authors.initials: D
authors.lastname: Ulmert
authors.forename: Linda
authors.initials: L
authors.lastname: Drevin
authors.forename: Mats
authors.initials: M
authors.lastname: Lambe
authors.forename: Pär
authors.initials: P
authors.lastname: Stattin
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood; D055088:Early Detection of Cancer / Q000379:methods / Q000706:statistics & numerical data / Q000639:trends; D006295:Health Resources / Q000706:statistics & numerical data*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D012189:Retrospective Studies; D018570:Risk Assessment; D013548:Sweden / Q000453:epidemiology; D019564:Unnecessary Procedures / Q000706:statistics & numerical data*
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen