Patient-Selection of a Clinical Trial Primary Outcome: The ENHANCE-AF Outcomes Survey

by Randall S. Stafford, Eli N. Rice, Rushil Shah, Mellanie T. Hills, Julio C. Nunes, Katie DeSutter, Amy Lin, Karma Lhamo, Bryant Lin, Ying Lu, Paul J. Wang

Before the initiation of the ENHANCE-AF clinical trial, which tested a novel digital shared decision-making tool to guide the use of anticoagulants in stroke prevention for patients with atrial fibrillation, this study aimed to identify the most appropriate, patient-selected primary outcome and to examine whether outcome selection varied by demographic and clinical characteristics.

Our cross-sectional survey asked 100 participants with atrial fibrillation to rank two alternative scales based on the scales’ ability to reflect their experiences with decision-making for anticoagulation. The Decisional Conflict Scale (DCS), a 16-item scale, measures perceptions of uncertainty in choosing options. The 5-item Decision Regret Scale (DRS) focuses on remorse after a healthcare decision. We included adults with non-valvular AFib and CHA₂DS₂VASc scores of at least 2 for men and 3 for women. Multivariable logistic regression with backward selection identified characteristics independently associated with scale choice.

The DCS was chosen over the DRS by 77% [95% confidence interval (CI) 68 to 85%] of participants. All subgroups designated a preference for the DCS. Those with higher CHA₂DS₂VASc scores (≥5, n = 26) selected the DCS 54% of the time compared with 86% of those with lower scores (p =  0.002). Multiple logistic regression confirmed a weaker preference for the DCS among those with higher CHA₂DS₂VASc scores.

Individuals with atrial fibrillation preferred the DCS over the DRS for measuring their decision-making experiences. As a result of this survey, the DCS was designated as the ENHANCE-AF clinical trial’s primary endpoint.