The main results related to the knowledge about radiation that is used in the different procedures are exposed in the in the Fig. 1 and it can be observed that when participants are asked whether General Radiology used ionizing radiation,
94.5% correctly answered.
So,
most of the respondents have notion that general radiology uses ionizing radiation.
Regarding the Computed Tomography,
responses were more divergent since 53.6% answered that it uses ionizing radiation during the exams.
In the case of magnetic resonance imaging,
49.3% of the respondents incorrectly thought that it used ionizing radiation.
When asked if the ultrasound used ionizing radiation,
87.3% correctly answered that it did not use ionizing radiation.
Regarding the question of whether bone densitometry uses ionizing radiation,
53.3% of the respondents correctly answered that it used ionizing radiation.
Similarly,
about mammography,
62.4% correctly answered that it used ionizing radiation.
Similar results were obtained by Costa (2015),
since the respondents when questioned about which modalities used ionizing radiation,
96.3% answered that conventional radiology use ionizing radiation,
76.6% that CT use ionizing radiation,
67.7% that bone densitometry use ionizing radiation and 67% answered that mammography use ionizing radiation.
The major differences are relative to the knowledge about Ultrasound (40.1% affirm that ultrasound use radiation) and MRI (78.8% said that MRI use radiation).
The Fig. 2 show the results related to radiation exposures and cancer risk.
We can see that 71.82% of the respondents correctly answered that the radiation increased the risk of having cancer.
Similarly,
82.87% correctly answered that repeated exposures increased cancer risk.
Therefore,
we can see that the participants have knowledge that radiation exposures is related to the likelihood of developing cancer.
In the present study respondents were asked whether they were exposed to ionizing radiation during a plane trip,
where 54.70% correctly answered.
When questioned about whether they were exposed to radiation at home,
72.38% of the respondents correctly answered,
so,
most respondents know that they are exposed to radiation at home.
Regarding the comparison of dose values between CT and radiography,
only 58% answered that CT used a higher dose.
Respondents were quite divided when asked who should provide radiation information,
54.14% chose the Medical doctor and 45.86% the Radiographer.
When questioning about the probability of a CT scan leading to a fatal cancer (Fig. 3),
only 6.63% correctly answered,
evidencing that they do not have the basics about the cancer risk from a CT scanning.
In a study conducted by Sin et al (2013),
for the same question,
17.8% of the respondents correctly answered.
This percentage is also low but higher when compared to the values of the present study.
It also should be noted that there were more correct responses from women than men.
70.49% of women did a correct answer in 9 or more questions (in a total of 15 and) and only 54.23% of men achieved the same.
With regard to literacy,
we can verify that in the range between 11 to 14 correct answers,
the higher the academic grade the higher the number of correct answers.
No one correctly answered to the 15 questions.