title: Agreement between risk and priority for heart transplant: Effects of the geographic allocation rule and status assignment.
abstract: BACKGROUND
  Allocation of donor hearts in the United States is accomplished by an algorithm based on status, time waited, and geographic boundaries. Although not designed to always transplant the highest acuity candidates, the ability of current United Network for Organ Sharing policies to prioritize highest acuity candidates is unknown.
  
  
  METHODS
  We analyzed 32,866 adult match runs generated from 2007 to 2014. Each candidate's sequence number within a match run was compared with the candidate's risk of mortality using Kendall's tau-b-a measure of rank correlation. Two primary methods of evaluating risk of mortality were used: status designation-based risk (i.e., status 1A risk > status 1B > status 2) and status justification-based risk (e.g., status 1A justified by presence of a complication).
  
  
  RESULTS
  Median sequence number for transplanted candidates was 3 (interquartile range [IQR]: 1, 9). Median correlation among match runs for status-based risk was 0.57 (IQR: 0.47, 0.66) and for justification-based risk was 0.51 (IQR: 0.39, 0.60). Sensitivity to status 2 candidates was evident when status 2 candidates were removed from the sample (status-based tau-b = 0.31, justification-based tau-b = 0.1) and with restriction of the data set to only the first 20 candidates (status-based tau-b = 0.35, justification-based tau-b = 0.15).
  
  
  CONCLUSIONS
  There is only mild correlation between status and priority under the current allocation algorithm and poor concordance when more detailed risks are considered. The geographic allocation rule is responsible for most of the measured discordance.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Washington, Seattle, Washington. Electronic address: tdardas@uw.edu.
authors.forename: Todd F
authors.initials: TF
authors.lastname: Dardas
authors.affiliation: Department of Biostatistics, University of Washington, Seattle, Washington.
authors.forename: Minkyu
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Biostatistics, University of Washington, Seattle, Washington.
authors.forename: Aasthaa
authors.initials: A
authors.lastname: Bansal
authors.affiliation: Department of Biostatistics, University of Washington, Seattle, Washington.
authors.forename: Patrick
authors.initials: P
authors.lastname: Heagerty
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Washington, Seattle, Washington.
authors.forename: Richard K
authors.initials: RK
authors.lastname: Cheng
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, University of Washington, Seattle, Washington.
authors.forename: Nahush A
authors.initials: NA
authors.lastname: Mokadam
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, University of Washington, Seattle, Washington.
authors.forename: Jay
authors.initials: J
authors.lastname: Pal
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, University of Washington, Seattle, Washington.
authors.forename: Jason
authors.initials: J
authors.lastname: Smith
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Washington, Seattle, Washington.
authors.forename: Claudius
authors.initials: C
authors.lastname: Mahr
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Washington, Seattle, Washington.
authors.forename: Wayne C
authors.initials: WC
authors.lastname: Levy
mesh_terms: D000328:Adult; D000465:Algorithms; D005500:Follow-Up Studies; D006333:Heart Failure / Q000401:mortality / Q000601:surgery*; D016027:Heart Transplantation; D006801:Humans; D012189:Retrospective Studies; D018570:Risk Assessment; D015996:Survival Rate / Q000639:trends; D014019:Tissue Donors; D009927:Tissue and Organ Procurement / Q000458:organization & administration*; D014481:United States / Q000453:epidemiology; D014850:Waiting Lists / Q000401:mortality*; D014861:Washington / Q000453:epidemiology
keywords: epidemiology; heart allocation; heart failure; transplant policy; transplantation