We carried out a quantitative and qualitative evaluation through a survey and focal groups to achieve a comprehensive picture of patients’ understanding of the benefits and risks associated with medical imaging and their opinions about how this type of information should be delivered.
Quantitative study:
We estimated that,
for a precision of 5% with 95% confidence intervals,
at least 384 people would be required to answer.
To allow for analysis by subgroups we increased this number to 600.
Sampling was carried out in stages and stratified by age.
Participants were contacted by phone,
oral informed consent was obtained.
We were unable to contact 50 participants and 10 declined to answer the survey.
Details of the sampling are shown on Fig 1.
The questionnaire (see Fig 2.) was filled out by 602 people.
418 (70.3%) participants stated that they were aware of the risk associated with radiation in imaging tests.
Awareness was higher among women,
in Health Department 17 and among people who said the had been informed about a prescribed imaging test.
People who received either written or both,
written and oral information were more likely to share the decission of having an imaging test with their physicians.
The same thing happened with people who thought the information they received was easy to understand.
On the other hand,
knowledge about what imaging test are related to radiation was inconsistent.
Most participants knew x-rays involve radiation,
but fewer were aware about the presence of radiation in CT and mammography and a substantial proportion believed MRI and ultrasound have radiation.
Fig 3 shows the results,
divided between participants who said they were aware about radiation risks and those who said they were not aware.
Qualitative study:
The two groups used an identical protocol and procedure,
which began with a short presentation by the head of the radiology department in each hospital and all participants being informed and consenting to the study.
The focus group discussions lasted between 60-90 minutes and were audio recorded
The research team developed a semi-structured focus group protocol to guide the discussion based on a literature review of radiation exposure topics.
The protocol was divided into two main themes: topic 1) Assessment of the information they receive before having an imaging test,
and topic 2) what information they would like to receive before undergoing an imaging test.
Moreover,
the participants assessed three potential information sheets detailing the radiation exposure risk associated with specific imaging tests to determine which they felt would be easiest to understand.
The information sheets (translated to english) are shown in figures 4-6.
The focus group discussions lasted between 60-90 minutes and were audio recorded.
A careful transcription reading was made and the text then split up into meaningful information units.
These units were coded following a mixed strategy (emerging and predefined codes according to the study objectives),
and categories were developed on the basis of grouping codes with the same topic.
Later,
the points of agreement and disagreement were analysed and triangulation of the results were performed to qualitatively analyse the degree of agreement.
Overall 20 people participated in the two focal groups,
12 women (60%) and 8 men.
Overall,
the interviewed population stated that they received little information regarding the radiological test they were going to have.
However,
few of the participants felt the need to ask the physicians for more information.
In fact,
most of them stated that they did not know enough about radiation exposure terms to understand the physicians’ explanation.
Despite this lack of specific information regarding the risks,
most of them agreed to sign the written informed consent especially as it was delivered to them just before the test was performed,
which could be perceived as being too late to say no.
Regarding the information sheets and what information would they like to receive before undergoing an imaging test,
participants stated that communication between health professionals regarding tests was limited. They also pointed out the importance of keeping count of the number of tests carried out on each patient.
Interviewed participants preferred both verbal and written information,
describing the benefits and risks of diagnostic imaging tests.
Furthermore,
they underlined the importance of receiving information in a summarized form that should include a bried description of the test and the purpose of doing it.
All of the participants agreed that the most appropriate way to present information was a table showing a number of imaging tests and their corresponding radiation equivalence in terms of chest X-rays and background radiation exposure (as shown in Fig 5).