BackgroundGeneral practitioners (GPs) often decide to refer patients for medical imaging with ionizing radiation and are therefore responsible for assessing the benefits of the procedure against the possible risks. ObjectiveTo assess the level of general practitioners’ knowledge concerning radiation doses for patients undergoing common radiological investigations and the associated risks of these radiation doses. MethodI used a self-administered postal questionnaire survey sent to all 200 GPs working in municipal general practices in Bergen to investigate their knowledge about radiation doses and the risks associated with ionizing radiation. ResultsThe response rate was 47%. Most GPs showed poor knowledge of radiation doses and associated risks. Male GPs had greater knowledge compared with female GPs (P=0.049). GPs with training in radiation safety had significantly greater knowledge compared with those with no radiation safety training (P=0.005). ConclusionOverall, GPs’ knowledge of radiation doses and the risks associated with ionizing radiation was reported to be poor.