An exploration of Canadian emergency physicians' and residents' knowledge of computed tomography radiation dosing and...

The objective of this study was to measure the current knowledge of Canadian emergency physicians and emergency medicine residents regarding computed tomography (CT) radiation dosing and its associated risks.

Three focus groups were conducted as the qualitative element of this study. Cognitive debriefing was carried out to ensure the validity and reliability of the focus group findings and to aid with survey development. A 26-item electronic survey was developed and pilot tested for distribution to the membership of the Canadian Association of Emergency Physicians.

Eighteen emergency medicine physicians and three emergency medicine residents participated in the focus groups. Four major themes emerged: 1) physician knowledge of risks associated with CT, 2) risk management strategies, 3) communication, and 4) knowledge translation. The survey response rate was 49.8% (638 of 1,281). The mean respondent age was 40.9±9.9 years, and 70.7% were male. Of all respondents, 82.5% were actively practicing attending physicians, 56.4% of all respondents practiced in urban academic emergency departments, and the average time practicing was 10.7±9.6 years. Radiography and CT were correctly identified by 92.2% and 95.1% of respondents, respectively, as sources of ionizing radiation, whereas magnetic resonance imaging and ultrasonography were selected by 1.0% and 0.5%, respectively. With respect to the lifetime attributable risk (LAR) of malignancy due to CT, 82.2% of participants correctly identified that abdominal CT increases the risk of cancer by 0.2 to 2%, whereas 51.3% correctly identified that the LAR increases twofold in a 7- year-old boy. When asked to identify populations at risk for potential harm due to ionizing radiation, 92.2% of respondents identified children, 80.3% identified pregnant women, and 71.4% identified women of reproductive age. A minority (37.2%) reported communicating the potential risks of CT to a majority of their patients. Electronic platforms were identified by 74.8% of respondents as their preferred method of knowledge translation on this topic.

Canadian emergency medicine physicians and emergency medicine residents demonstrated identifiable gaps in knowledge surrounding CT radiation dose and risk.