Differences in the radiation knowledge index (RKI) between male and female respondents (N=120)
| Gender | N | Mean rank | Sum of ranks | P* |
|---|---|---|---|---|
| Male | 20 | 75.25 | 1505.00 | 665.000; 0.023 |
| Female | 98 | 56.29 | 5516.00 | |
| Total** | 118 |
Group mean scores in the answers to the last question by specialisation among Croatian GPs (N=120)
| Abdominal CT | Intravenous urography | Barium meal | Lumbar spine CT | Brain MRI | Brain MRI with contrast | Lumbar spine X-ray | Mammography | Renal ultrasound | |
|---|---|---|---|---|---|---|---|---|---|
| Correct answer | 6 | 4 | 5 | 4 | 1 | 1 | 3 | 1 | 1 |
| Family medicine specialists | 3.95* | 3.5* | 3.1* | 3.76 | 1.17* | 1.49* | 1.73* | 1.51* | 1 |
| Family medicine residents | 3.77* | 2.77* | 2.68* | 3.32* | 1.21 | 1.5* | 1.3* | 1.61* | 1 |
| Others | 4.57* | 3.26* | 3.21* | 3.75 | 1.11 | 1.26 | 1.6* | 1.45* | 1 |
Test of distribution normality for RMD values for the three specialisations
| RMD | Kolmogorov-Smirnova | Shapiro-Wilk | ||||
|---|---|---|---|---|---|---|
| Statistic | df | Significance | Statistic | df | Significance | |
| Family medicine specialists | 0.312 | 9 | 0.012 | 0.844 | 9 | 0.065 |
| Family medicine residents | 0.224 | 9 | 0.200 | 0.910 | 9 | 0.317 |
| Others* | 0.211 | 9 | 0.200 | 0.878 | 9 | 0.151 |
Sociodemographic data of participating general practitioners from Croatia (N=120)
| Mean age (and range) (years) | 44.2 (26–65) | |
| Gender* (%) | Female | 83.1 |
| Male | 16.9 | |
| Specialisation (%) | Family medicine | 57.5 |
| Family medicine residents | 23.3 | |
| Others (no specialisation or any other specialisation working as GP) | 19.2 | |
| Mean years of service (and range) | 17.1 (1–40) | |
| Have you ever taken any radiation protection course? (%) | yes | 5.8 |
| no | 94.2 |
Pairwise comparison of RMD scores between specialisation groups
| Paired differences | t | df | Significance (two-tailed) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean | SD | SE | 95 % Confidence interval of the difference | ||||||
| Lower | Upper | ||||||||
| Pair 1 | Family medicine specialists vs residents | −0.261 | 0.255 | 0.085 | −0.457 | −0.065 | −3.078 | 8 | 0.015 |
| Pair 2 | Family medicine specialists vs others | 0.078 | 0.244 | 0.081 | −0.109 | 0.265 | 0.956 | 8 | 0.367 |
| Pair 3 | Residents vs others | 0.339 | 0.249 | 0.083 | 0.148 | 0.530 | 4.085 | 8 | 0.004 |
Differences in the radiation knowledge index between specialisations (N=120)
| Specialisation | N | Mean rank | P* |
|---|---|---|---|
| Family medicine specialists | 69 | 57.33 | 1.602; 0.449 |
| Family medicine residents | 28 | 62.68 | |
| Others | 23 | 67.35 | |
| Total | 120 |
Replies of Croatian GPs (N=120) to the third set of multiple choice questions establishing their knowledge of radiation exposure through diagnostic imaging procedures (correct answers are in boldface)
| Question | Reply (%) |
|---|---|
| Which of the selected imaging procedures do not expose patients to ionising radiation? | |
| Plain radiography | 0.8 |
| CT scan | 1.7 |
| MRI | 97.5 |
| Angiography | 0 |
| When selecting the appropriate radiologic procedure, what is the priority? | |
| To minimise radiation dose | 27.5 |
| To address the clinical issue | 69.2 |
| To reduce diagnostic expenses | 0 |
| To avoid radiation | 2.5 |
| Don’t know | 0.8 |
| What age is most at cancer risk because of radiation exposure? | |
| 10 years | 73.3 |
| 30 years | 5.8 |
| 50 years | 5.8 |
| 70 years | 3.3 |
| Don’t know | 11.7 |
| Which of the selected imaging procedures involves highest ionising radiation doses? | |
| Plain radiography | 89.2 |
| MRI | 0 |
| Mobile phone | 7.5 |
| Ultrasound | 0 |
| Don’t know | 3.3 |
| Repeated brain CT can cause: | |
| Headaches | 8.5 |
| Cataract | 59.3 |
| Nothing | 0.8 |
| Don’t know | 31.4 |
| The lowest lethal effective dose of radiation is: | |
| 0.5 Sv | 1.7 |
| 5 Sv | 15.8 |
| 50 Sv | 11.7 |
| 500 Sv | 12.5 |
| Don’t know | 58.3 |
| The most sensitive organ to ionising radiation is: | |
| Skin | 8.3 |
| Bone marrow | 69.2 |
| Thyroid gland | 15.8 |
| Don’t know | 6.7 |
| How important it is to know about ionising radiation in diagnostic imaging | |
| Very important | 59.2 |
| Important | 37.5 |
| Less important | 3.3 |
| Unimportant | 0 |
Replies of Croatian GPs (N=120) to the second set of yes/no questions establishing their referral practices and general knowledge of radiological procedures (preferable/correct answers are in boldface)
| Yes | No | |
|---|---|---|
| % | ||
| Have you ever been asked by a patient to provide additional information about the radiological procedure to which you refer them? | 69.2 | 30.8 |
| Do you inform your patients sufficiently about radiological procedures to which you refer them? | 88.3 | 11.7 |
| Is informing patients necessary? | 97.5 | 2.5 |
| Can some radiological procedures irradiate patient's body? | 100.0 | |
| Can radiation harm patients' health? | 91.6 | 8.4 |
| Can single exposure to ionising radiation during a radiological procedure increase the risk of cancer? | 47.5 | 43.3 |
| Can repeated exposure to ionising radiation during radiological procedures increase the risk of cancer? | 94.2 | 4.2 |
| Is your knowledge of ionising radiation involved in radiological procedures sufficient for your daily work at the clinic? | 27.5 | 72.5 |
Replies of Croatian GPs (N=120) to the question: "If the single chest X-ray is taken as a dose unit, how much radiation does a person receives during the following procedures?" (correct answers are in boldface)
| Chest X-ray unit* (score) | |||||||
|---|---|---|---|---|---|---|---|
| Procedure | 0 (1) | 1–49 (2) | 50–99 (3) | 100–199 (4) | 200–499 (5) | ≥500 (6) | Do not know/blank (0) |
| Abdominal CT | 1.7 | 15.8 | 17.5 | 10.8 | 14.2 | 21.7 | 18.3 |
| Intravenous urography | 6.7 | 20.8 | 15.8 | 15.8 | 15.0 | 3.3 | 22.5 |
| Barium meal | 11.7 | 20.8 | 14.2 | 13.3 | 12.5 | 2.5 | 25.0 |
| Lumbar spine CT | 2.5 | 15.0 | 18.3 | 14.2 | 22.5 | 3.3 | 24.2 |
| Brain MRI | 73.3 | 1.7 | 2.5 | 0.8 | 0.0 | 0.8 | 20.8 |
| Brain MRI with contrast | 58.3 | 10.8 | 2.5 | 1.7 | 3.3 | 0.0 | 23.3 |
| Lumbar spine X-ray | 47.5 | 20.0 | 6.7 | 3.3 | 0.8 | 0.0 | 21.7 |
| Mammography | 50.8 | 21.7 | 6.7 | 2.5 | 0.0 | 0.0 | 18.3 |
| Renal US | 80.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 20.0 |