What do patients know about ultrasound, CT and MRI?

To establish the level of patient knowledge of ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI); to describe patient information-seeking behaviour before attendance; and to assess patients' understanding of the main aspects of scanning examinations.

Survey of people attending for ultrasound, CT and MRI using a questionnaire, including 12 statements on simple aspects of procedures, to be indicated as true or false.

Radiology department of an acute teaching hospital NHS Trust in the north-east of Scotland.

A convenience sample of 500 out-patient, non-emergency first time attenders for ultrasound (300), computed tomography (150), and magnetic resonance imaging (50).

An 82% response rate to the questionnaire was achieved. Less than half the patients (48.9%, 182/372) indicated they knew the type of investigation they had been referred for. When responses were compared with referral letters, 64% (238/372) were incongruent. Few participants hadsought information (32%, 120/372), but of those who had the main source was family and friends (72%, 86/120). Seven participants searched the Internet. Eighty-two percent (308/372) of participants reported having been given an explanation of why an investigation was necessary. The majority of participants (67.8%, 251/372) expected to receive their results within 2 weeks. The mean score on the 12 true/false knowledge statements was 3.8, and 17% (65/372) answered 'Don't know' to all the statements. One person answered all questions correctly.

Patients were not well informed regarding these investigations. This has significant implications for information-giving strategies and informed consent.