Knowledge of computed tomography dose optimisation and justification among CT users and referring physicians: a single hospital study

Abstract

Introduction: Radiation dose associated with computed tomography (CT) remains a concern, and radiation risk does not receive the needed attention, especially in low and middle-income countries. This because the frequency of this high-dose examination is rapidly growing and systems for protocol optimisation and dose justification are yet to be provided in CT imaging. Objective: To determine radiographers' and radiologists' awareness and knowledge of CT dose optimisation. We also determined knowledge of dose justification and use of the referral guidelines amongst the referring physicians. Methods: Radiographers and radiologists were invited to complete a web-based questionnaire whilst the referring physicians completed a self-administered questionnaire. The returned questionnaires were analysed and a significant difference was determined using Yates corrected Chi-square, and a p-value of 0.05 was considered at the 95% confidence interval. Results: The response rates were 50% (17 out 34) and 35% (16 out 46) for radiographers and radiologists respectively while referring physicians had a response rate of 84% (92 out of 110). Overall, more radiographers (47.1%) than radiologists (18.8%) had good knowledge of CT doses and image quality, however, the difference in knowledge was not found to be significant (p = 0.167). In addition, knowledge of diagnostic reference levels (DRLs) was significantly (p = 0.033) higher amongst radiographers (52.9%) as compared to radiologists (12.5%). Meanwhile, physicians understood the principles of dose justification. However, their knowledge of referral guidelines was limited. Conclusion: The study revealed that radiographers were more knowledgeable on matters relating to radiation dose and image quality as well as DRLs when compared to radiologists. Meanwhile, the concept of dose justification was understood among physicians, however, they had limited awareness and knowledge of referral guidelines.