Journal of General Internal Medicine

, Volume 2, Issue 3, pp 141–148 | Cite as

Initiation of warfarin therapy

Comparison of physician dosing with computer-assisted dosing
  • Richard H. White
  • Robyn Hong
  • Alan P. Venook
  • Martha M. Daschbach
  • William Murray
  • Dennis R. Mungall
  • Robert W. Coleman
Original Articles


In a prospective, randomized study at two university hospitals, the authors examined how effectively housestaff physicians (n=36) managed the initiation of warfarin therapy compared with a computer-assisted dosing regimen (n=39) using the software program Warfcalc, which was managed by one of the authors. Target prothrombin time ratios were selected by the physicians. Study endpoints included: the time to reach a therapeutic prothrombin ratio, the time to reach a stable therapeutic dose, the number of patients transiently overanticoagulated, the number of bleeding complications, and the accuracy of the predicted maintenance dose, which was assessed at steady-state 10–14 days later. Computer-assisted dosing consistently outperformed the physicians: a stable therapeutic dose was achieved 3.7 days earlier (p=0.002), fewer patients were overanticoagulated (10% versus 41%), and the predicted maintenance dose was in the therapeutic range in 85% of the computer-dosed patients versus 42% of the physician group (p<0.002). For physicians who did not routinely manage warfarin therapy, computer-assisted dosing improved the accuracy of dosing and shortened the time required to achieve a stable therapeutic dose.

Key words

warfarin anticoagulation medical computing 


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Copyright information

© Society for Research and Education in Primary Care Internal Medicine 1987

Authors and Affiliations

  • Richard H. White
    • 2
  • Robyn Hong
    • 1
  • Alan P. Venook
    • 2
  • Martha M. Daschbach
    • 2
  • William Murray
    • 1
  • Dennis R. Mungall
    • 3
  • Robert W. Coleman
    • 1
  1. 1.the Department of PharmacyVeterans Administration Medical CenterPalo Alto
  2. 2.the Division of General MedicineUniversity of California, Davis, Medical CenterSacramento
  3. 3.the Clinical Research DepartmentBiotrack, Inc.Sunnyvale

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