A Randomized Trial of Decision-making in Asymptomatic Carotid Stenosis

Objective: We sought to evaluate whether different presentation formats, presenter characteristics, and patient characteristics affect decision-making in asymptomatic carotid stenosis.

Methods: Subjects included individuals presenting to a neurology clinic. Participants included those over age 18 without known carotid stenosis. Subjects were randomized to a 30-second video with 1 of 5 presentation formats (absolute risk, absolute event-free survival, annualized absolute risk, relative risk, and a qualitative description) delivered by 1 of 4 presenter physicians (black woman, white woman, black man, white man). Subjects then completed a one-page form regarding background demographics and their decision regarding treatment choice.

Results: A total of 409 subjects watched the video and completed the survey. Overall, 48.4% of subjects chose surgery. Presentation format strongly predicted choice of surgery (qualitative [64%], relative risk [63%], absolute risk [43%], absolute event-free survival [37%], and annualized absolute risk [35%], p < 0.001). There was a trend for younger age (mean age 52 vs 55, p = 0.054), male gender (53% vs 45%, p = 0.08), and advanced education (42% for high school education or less vs 52% for more than high school education, p = 0.052) to predict surgery choice. Gender and race of presenter, and race of subject, had no influence on the choice of treatment.

Conclusions: Presentation format (information framing) strongly determines patient decision-making in asymptomatic carotid stenosis. Subject age, gender, and education level may also influence the decision. Clinicians should consider the influence of these variables when counseling patients.