title: Shared patient analysis: a method to assess the clinical benefits of patient referrals.
abstract: BACKGROUND
  Referral to specialized physicians or institutions often is deemed necessary in clinical medicine, but no method exists to assess the clinical benefit of such referrals.
  
  
  OBJECTIVE
  To describe a method, which is shared patient analysis, to measure the expected improvement in clinical management associated with referrals and to apply that method in the field of abdominal and pelvic oncological radiology.
  
  
  METHODS
  All patients referred, during a 4-year period, to surgical oncologists at four academic centers (the referral providers, or RPs) with radiographs performed before referral at a community site (the initial providers, or IPs). Patients (n = 396) for whom both the IP interpretation and a final diagnosis was available were eligible. All IP and RP readings were placed in random order and presented to surgical oncologists, who then recommended a treatment course.
  
  
  METHODS
  Diagnostic accuracy of the IP and RP readings and the proportion of patients who were assigned to an appropriate treatment by the oncologist were determined.
  
  
  RESULTS
  When the indication for imaging was primary diagnosis or staging, the kappa for presence of cancer was 0.70. When the indication was cancer follow-up, the kappa for presence of recurrent/progressing cancer was 0.66. There were disagreements between the IP and RP radiologists over the interpretation of 162 films, with the RP radiologists being correct in 153 (94%). Had the patients been treated using IP readings, there would have been 19 more inappropriate surgeries and 19 more admissions (both P <0.05) than if the oncologists had based their recommendations on RP readings.
  
  
  CONCLUSIONS
  The technique of shared patient analysis permits assessment of the clinical benefits associated with referrals.
authors.affiliation: Department of Medicine, University of California, San Francisco 94118, USA. adudley@itsa.ucsf.edu
authors.forename: R A
authors.initials: RA
authors.lastname: Dudley
authors.forename: H
authors.initials: H
authors.lastname: Hricak
authors.forename: J
authors.initials: J
authors.lastname: Scheidler
authors.forename: K K
authors.initials: KK
authors.lastname: Yu
authors.forename: C L
authors.initials: CL
authors.lastname: Kalbhen
authors.forename: C B
authors.initials: CB
authors.lastname: Powell
authors.forename: L
authors.initials: L
authors.lastname: Schwartz
authors.forename: E M
authors.initials: EM
authors.lastname: Yetter
authors.forename: C M
authors.initials: CM
authors.lastname: O'Malley
authors.forename: R
authors.initials: R
authors.lastname: Warren
mesh_terms: D000046:Academic Medical Centers; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009369:Neoplasms / Q000175:diagnosis*; D016522:Oncology Service, Hospital / Q000592:standards* / Q000706:statistics & numerical data; D010347:Patient Care Planning; D011785:Quality Assurance, Health Care / Q000379:methods*; D012017:Referral and Consultation / Q000592:standards* / Q000706:statistics & numerical data; D014057:Tomography, X-Ray Computed; D014481:United States