Doctors’ knowledge of radiation — a two-centre study and historical comparison

Abstract

To investigate knowledge of the use of ionizing radiation in 2010 and whether there has been any change in this knowledge since the study was first undertaken over 7 years ago. In both studies a single chest x-ray was classed as one unit of radiation. Doctors from all grades were asked to evaluate the average radiation dose incurred with 13 commonly undertaken radiological procedures, including magnetic resonance imaging (MRI), computed tomography (CT), etc. Answers within 20% of the actual dose were marked as correct. Two hundred and forty-two questionnaires were completed (130 in 2003; 112 in 2010). Equal numbers of juniors, middle grades, and consultants were questioned, and scores were comparable (23.3% in 2003; 29.4% in 2010). The majority of doctors (92% in 2003; 86% in 2010) correctly noted that ultrasound and MRI involve no radiation. Doctors underestimated the radiation doses of all investigations by a smaller margin in 2010 compared to 2003 (i.e., more accurately), with only one exception: CT of the abdomen. Despite evidence of some improvement, doctors of all grades still have a very poor knowledge of radiation exposure even with the most common investigations. The worsening appreciation of the radiation involved in CT scanning is especially worrying considering its increasing use in practice today.