The online questionnaire received a total of 85 responses, across 23 countries. The responses for question 1 are not included in these results as this question collected personal information about the respondents and their institution. The results for questions 13, 14 and 15 are not reported as they do not relate to CT examinations.
Question 4—do you have a dose tracking/management system in your hospital?
This question received 70 responses and was skipped by 15. Of those who responded, 53 (75.7%) indicated that they have a dose tracking/management system in their hospital, 14 (20%) do not and 3 (4.3%) answered ‘other’ (Fig. 1). The 3 respondents that answered other all indicated that they had some form of dose tracking; one indicated that they had limited tracking capabilities, one had a newly installed dose management system (DMS) that is not yet fully utilised and another indicated that they have a self-developed dose management system.
Question 5—what percentage of patients, who have had recurrent CT examinations, received a cumulative effective dose (CED) ≥ 100 mSv?
This question received 18 responses, from individual institutions, covering a total of 1,218,429 patients, of which 6082 received a cumulative effective dose of (CED) ≥ 100 mSv. The percentage of patients who have received a cumulative effective dose (CED) ≥ 100 mSv, over the period of 2015–2018, ranges from 0 to 2.72%. The mean is 0.5% (Fig. 2).
Of those who responded to this question, 15 had a DMS, 2 indicated ‘other’ and 1 did not specify. For those that answered other, 1 indicated they had a self-developed DMS and the other that they had limited dose tracking. In terms of geographical distribution, the responses to this question came from the following countries: 2 from France, 1 from Germany, 5 from Italy, 3 from Spain, 1 from the UK, 3 from Turkey, 1 from Austria and 2 did not report their country. Additionally, of the 18 responses, 12 came from academic hospitals, 3 from general hospitals and 3 did not provide this data.
Question 6—please provide the numbers of adult patients, from the following categories, who have had a cumulative effective dose (CED) ≥ 100 mSv
This question was answered by 15 respondents, with the data covering a total of 903,336 patients, of which 3405 patients had a cumulative effective dose (CED) ≥ 100 mSv between 2015 and 2018 (Fig. 3). Of these patients, 1976 had an oncologic disease, 466 had a chronic disease, 718 were trauma patients, 43 had a transplant and 202 were indicated as ‘other conditions’ (which included 22 follow-up of post bariatric surgery, 16 cardiac complications and 135 post-operative complications; a further 29 were not specified).
Question 7—please provide the numbers of children, from the following categories, who have had a cumulative effective dose (CED) ≥ 100 mSv
All 14 responses, corresponding to 903,365 patients who received CT scans, reported that no paediatric patients, for any of the categories, received CED ≥ 100 mSv. The available categories were oncologic disease, chronic disease, trauma patients, transplant and other.
Question 8—which action(s) for improving the process to justify recurrent scans would be most effective in reducing the rate of repeat examinations?
This question was answered by 31 respondents and skipped by 54. Of the responses, 16 (51.6%) selected development and implementation of updated guidelines for cumulative doses, 16 (51.6%) selected implementation of alerts that take into account the number of previous examinations, 21 (67.7%) selected providing information about previous imaging exams to referrers and practitioners, 22 (71.0%) selected use of dose management systems and 3 (9.7%) selected other (Fig. 4).
The responses for other were that every CT scan needs to be justified regardless of prior exams and it would therefore be dangerous to withhold examinations because a patient had another CT before and 2 responses were that the routine use of clinical decision support tools would help.
Question 9—which action(s), relating to the optimisation of examinations, do you think would be most effective in reducing cumulative dose?
This question was answered by 32 respondents and skipped by 53. Of the responses, 21 (65.6%) selected low-dose and ultra-low dose exams especially in repeat investigations, 15 (46.9%) selected effective and transparent dose management, 20 (62.5%) selected introducing monitoring and recording tools to standardise the documentation of patient dose in electronic health records, 12 (37.5%) selected developing non-ionising imaging investigations, 10 (31.25%) selected clinical audit tools and 2 (6.25%) selected other. For those who answered other, one suggested that CT protocol management would be effective; the other commented that changing dose based on previous examinations per se is the wrong approach as if the dose can be lowered, it must be lowered, regardless of repeat examinations (Fig. 5).
Question 10—is dose management mandatory in your country?
This question was answered by 35 respondents, with 18 (51%) answering that dose management is mandatory in their country and 17 (49%) answering that it is not mandatory.
Question 11—do you think dose management should be mandatory in your country?
This question was answered by 33 and skipped by 52. All 33 (100%) respondents answered that they think dose management should be mandatory in their country (the responses came from the following countries: 2 from Austria, 1 from Belgium, 3 from Croatia, 1 from the Czech Republic, 3 from France, 3 from Germany, 1 from Hungary, 1 from Ireland, 5 from Italy, 1 from the Netherlands, 1 from Portugal, 4 from Spain, 1 from Switzerland, 2 from Turkey, 1 from the UK; a further 3 responses did not indicate their country).
Question 12—please select which of the following parameters are required for reporting CT examinations
Question 12 was answered by 17 respondents and skipped by 68. Of which, 14 (82.4%) selected CTDIvol, 14 (82.4%) selected DLP, 2 (11.8%) selected effective dose and 2 (11.8%) selected other (Fig. 6). The responses for those that answered other included the number of irradiation events.
Question 16—please provide any comments you have about the survey
Three respondents commented that they were unable to provide any information on the number of patients who received CED ≥ 100 mSv, of which 2 indicated this was due to a lack of a dose management/tracking system to record this data.