- Background Screening for various diseases is now being offered to the public in settings other than their physicians' office, often using expensive and sophisticated technology. Little is known about how patients decide to participate in such programs, whether they understand the implications of a positive or negative test, or if their primary care physician is involved in the decision to screen. Methods We surveyed a cohort of patients who participated in a free carotid artery screening using Doppler ultrasound at a tertiary care academic medical center. Results One hundred twenty-four patients participated and underwent the ultrasound exam. Their mean age was 68.8 (±9.8) years and 54% were female. Some 117 patients (94%) completed the survey. Five patients (4%) tested positive for significant carotid artery stenosis. Sixty-two percent (95% CI: 53–71%) of the patients learned about the program through a newspaper advertisement. Eighty-eight percent (95% CI: 82–94%) of the subjects stated that their primary physician had not suggested that they have the test, and 59% (95% CI: 50–68%) did not know that carotid artery surgery is often recommended for patients who test positive. Conclusions This study of one group of patients who voluntarily took a screening test for carotid artery stenosis raises some important questions since most subjects did not understand the implications of a positive result, nor did they involve their physicians in their decision to take the test. Further studies are needed to evaluate whether providing patients with more information about the implications of a screening test would change their desire to have the test and about the nature of the informed consent required before such screening is carried out.