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Anne M Holbrook
Eleanor M Pullenayegum
Sue M Troyan
Milica Nikitovic
Mark A Crowther


Warfarin, benefit-harm relationships, decisional conflict, patient decision aids, atrial fibrillation


Providing information tailored to an individual patient’s potential for benefit and harm, sufficient to allow for informed decision-making, is both time consuming and complicated.

We sought to determine whether presentation of different levels of personalization of chances of benefit and harm would influence patient decisions regarding warfarin treatment for atrial fibrillation (AF).

Randomized sequence study recruited participants 55 years or older who were at risk for atrial fibrillation but not currently taking warfarin. Using a standardized decision aid, patients considered 5 scenarios involving 3 levels of personalization (average, individualized, and individualized combined). The primary outcome was the simulated decision whether or not to take warfarin. Secondary outcomes included decisional conflict, factors influencing the decision and preferences for decision-making involvement.

71 of 75 patients randomized (mean age 69.8 yr, 50.7% female) completed the study. Compared with the presentation of average risks of benefit and harm, the tailored information by clinical prediction rule or by combined benefit-harm scenarios caused a significant change in the decision to take warfarin (p<0.0001). Presentation of the competing risk of death with and without treatment also had a significant effect on treatment choice (p<0.0001). At most, 46 (64.8%) reported being willing to take warfarin. Mean decisional conflict between presentation types did not differ, but patients rated the combined benefit-harm presentation as the most helpful (p = 0.04).

Information tailored towards individual chances of benefit and harm, although more complex, is preferred by patients and can change treatment decisions

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