Affiliation:
1. Bob Champion Research and Education Building, Norwich Medical School, University of East Anglia, UK
2. Department of Urology, Norfolk and Norwich University Hospitals, UK
Abstract
Background: This study analyses patients’ knowledge of common radiological investigations. Methods: At a university teaching hospital, 100 patients attending urological clinics, who had had a plain X-ray of the kidney, ureter and bladder, magnetic resonance imaging (MRI), computed tomography (CT) or ultrasound scan (USS), completed a 14-item Likert scale questionnaire assessing patients’ perception of safety (both qualitatively and quantitatively) and the hazards of radiological investigations. Results: Using a radiation risk score, patients perceived the following investigations to be in rank order of increasing radiation risk: USS (0.84), MRI (1.4), CT (1.5) and plain X-ray (1.6). On the same scale (0–5), only 17% of patients correctly attributed a risk score of 3 or 4 for a CT scan, and 49% were able to identify a plain X-ray’s risk score correctly as 1 or 2. In addition, more patients identified CT (34%) as having a lower risk of 0 than an X-ray (24%). The mean (1.35 vs. 1.60), median (1 vs. 1) and mode (0 vs. 1) for the CT risk scores are less than those for a plain X-ray, demonstrating that patients perceived CT scans to be safer. Further, the majority of patients understood USS to have no radiation exposure (56%) but thought that MRI posed a radiation risk (62%). Patients were unable to quantify radiation exposure correctly: USS (37% correctly attributed – 0 mSv), MRI (22% – 0 mSv), X-ray (47% – 1 mSv) and CT scan (28% – 10 mSv). Conclusion: This demonstration of suboptimal patient awareness of radiation exposure of common radiological investigations highlights the need to educate patients in order to improve patient autonomy and possibly reduce the demand for unnecessary radiological investigations such as CT. Level of evidence: Level 2.