To our knowledge, this is the first study providing a comprehensive insight into radiology practitioners’ and radiographers’ level of awareness concerning radiation doses typically associated with paediatric MI examinations. Consequently, it is the first study exploring the use of referral guidelines and the level of awareness of paediatric imaging radiation doses amongst imaging practitioners in Malta.
While comparison of results is rather limited, since previously published studies did not solely focus on paediatric imaging examinations and did not make use of an identical research design or questionnaire, it is evident that the findings of this study are consistent in reporting a poor level of radiation dose awareness amongst health professionals [13–24]. In fact, on average, only 20 % of the participating radiology practitioners and radiographers were aware of the estimated ED for five paediatric radiation-based MI examinations, with the percentage of correct ED estimations varying from 9.6 to 32.4 %. Furthermore, while the majority were aware that MRI and ultrasound did not use ionising radiation, two radiology trainees and sixteen radiographers did not know this or else allocated an ED for such examinations. While it is possible that the radiology trainees incorrectly answered this question as they were still in the early stage of their training, we cannot explain why so many radiographers got this wrong. Consequently, although these findings are consistent with what has been reported previously for medical physicians, paediatricians, and surgeons [16, 18, 21–24], such a lack of awareness amongst imaging practitioners raises some concern, particularly in view of the important role they may have in the justification of paediatric MI examinations, whereby the use of ultrasound or MRI should be considered and encouraged when such examinations are likely to provide the necessary diagnostic information within a reasonable time.
When considering previously published research, two studies were found asking their respondents to provide an ED estimate for a paediatric chest CT [16, 24] and a paediatric abdominal CT. Just over a third (35 %) of participating paediatricians and 21.7 % of participating paediatricians, surgeons, and general practitioners respectively provided a correct ED estimate for the paediatric CT examination [16, 24]. Consequently 40.3 % of participating paediatricians, surgeons, and general practitioners correctly provided the dose estimate for the paediatric abdominal CT examination . In comparison, 24.5 and 21.2 % respectively provided the correct ED estimate for the paediatric chest and abdominal CT examinations in this study, despite the fact that one would probably expect radiology practitioners and radiographers to demonstrate a better understanding than other health professionals in this regard. Consequently, most of our study’s findings seem to be consistent with those reported in other studies, which assessed radiation dose awareness of different adult MI examinations. Indeed, the 21.2 % who correctly estimated the ED for an abdominal CT scan (5 year old) in this study are similar to those reported by Lee et al., whereby 22 % of physicians and 15 % of radiologists correctly estimated the ED of an adult abdominal CT scan . Moreover, these findings are better than those reported in two previously published UK studies, within which only 7–8 % of participating physicians respectively provided the correct ED estimate for an abdomen CT scan and for the foetal dose for a CT pulmonary angiography examination [20, 34].
More than a third (34.3 %) of participants overestimated the associated ED for a paediatric CT head scan, which is the most common CT examination performed in paediatric patients; while another 27.5 % and 24.0 %, respectively, overestimated the ED typically associated with CT thorax and CT abdomen scans performed on a 5-year-old. In the absence of local diagnostic reference levels for paediatric CT examinations, we believe that these findings are significant because, if radiology practitioners and radiographers incorrectly perceive the ED of these common paediatric CT scan examinations to be higher than they typically should be, this may limit them from identifying those examinations which are yielding an excessive dose and that require child-sizing (optimisation) of scan parameters and/or technique.
Conversely, about 24 % of responses in this study related to an underestimated ED. While this was much lower than that reported by Shiralkar et al. whose study sample of 130 doctors (including ten consultant radiologists) underestimated 97 % of the actual dose of various adult MI examinations , we feel that it is still an important finding. Indeed, underestimation of dose may not only lead to an incorrect perception of the risks involved, but it may also precondition the imaging practitioner in believing that, since the ED is low, the need to optimise such an examination is also low. Furthermore, since nearly half (48.0 %) of the participating imaging practitioners underestimated the ED associated with an abdominal CT scan performed on a 1-year-old patient, we believe that this may reflect imaging practitioners’ lack of consideration of the fact that younger paediatric patients receive a much higher ED per unit of radiation when compared to adults undergoing the same examination. In addition, when considering that 78.3 % either did not know or else underestimated the potentially high ED of a fluoroscopically-guided coronary angiography intervention, one may question whether imaging practitioners involved in such procedures are attentive to optimise their technique and exposure parameters so as to reduce the possibility for adverse tissue reactions and stochastic effects.
It was surprising to note that only one statistically significant difference was found in the responses provided by radiology practitioners and radiographers, although we do recognise that the small sample of radiology practitioners may have contributed to this result. This difference related to the statement concerning the principle of optimisation, whereby 95 % of radiographers correctly recognised that consideration of radiation dose is an important aspect of optimisation in comparison to the 75 % of radiology practitioners. While this may reflect radiographers’ active role in the optimisation of MI examinations, it is slightly concerning to note that 25 % (n = 3) of radiology practitioners were of the opinion that each medical exposure should produce the best imaging quality for diagnosis. Indeed, this finding raises questions as to the potential effect this particular mindset can have in practice, particularly in view of radiology practitioners’ input into imaging protocols, as well as them requesting that an imaging examination needs to be repeated.
Consistent with findings of a report published by the European Commission , the majority of participating radiology practitioners and radiographers were not aware or else did not use referral guidelines. This was a rather unexpected finding since each staff member had received an internal circular when the RP118 document was established as the official referral guidelines for all imaging examinations at the hospital during the previous year . Nonetheless, as recognised in the EU report, additional measures are needed on both a European and national levels to reinforce the use of guidelines, particularly since they are specifically designed to help health professionals in deciding the most appropriate imaging examinations for given clinical indications/scenarios. Furthermore the literature suggests that the use of referral guidelines has the potential to bring about a 13–20 % reduction in referral rates, which in turn may lead to a potential dose saving for patients . Therefore, coupled with the poor level of awareness concerning radiation doses demonstrated by this study’s participants, it is recommended that all local radiology practitioners and radiographers are not only made aware of that such guidelines exist, but they should also be educated and trained on how to make effective use of them during the justification process as well as in their discussions with referring physicians and patients.
Half of the radiology practitioners and radiographers reported that they had undertaken a maximum of 20 h of radiation protection education and training, which is much less than the recommended 30–50 h for radiology practitioners and 100–140 h for radiographers . While this may possibly be true for radiology practitioners who only receive radiation protection education and training during their postgraduate studies and/or radiology specialisation, it does not reflect the number of hours most radiographers perform as part of their undergraduate radiography course programme. For this reason, we believe that participants may have underreported the amount of hours of radiation protection education and training received, possibly by overlooking a number of topics that are interrelated to physiological/pathological processes and or radiology/radiography principles. Nonetheless, given that a considerable number of participants indicated that they had not undertaken radiation protection education/training for at least 5 years, it is important that imaging practitioners to recognise the importance of remaining up to date with the latest techniques, devices and software that can contribute to considerable radiation dose savings for their patients and fellow colleagues.
Strengths and limitations
The questionnaire used for the study was designed following a thorough process that assessed and verified its reliability and validity. We believe that it is also the first questionnaire to specifically explore the level of radiation dose awareness of paediatric imaging examinations amongst radiology practitioners and radiographers. The 66.7 % response rate obtained in this study was quite satisfactory, although we must also acknowledge that the responses provided may not necessarily be representative of the entire population of radiology practitioners and radiographers working at this primary paediatric referral centre in Malta. Nonetheless, we do believe that our study sample is comparable to the target population of imaging practitioners, particularly since the characteristics represented in our study sample are consistent with those of the relatively young workforce of radiology practitioners and radiographers at the hospital studied. Furthermore we also recognise that the use of questionnaires has its own limitations, with the possibility that some participants may not have been truthful in responses concerning their opinion, perception, or actual practice. We also recognise that participants had the opportunity to refer to textbooks and/or internet resources to complete the questionnaire. Nonetheless, given the busy work schedules that both radiology practitioners and radiographers generally have, we believe that it is unlikely that many of the participants would have taken the time to search for the most appropriate responses for the questions posed in our questionnaire.