Table 2 Health system and local context impacting on the ordering of CT scans

Australian practices

… the Australian doctors that I worked with there certainly are more risk averse and I think that they're just so scared of whether it's being sued or whether it's what their peers will think or I don't know where the feeling comes from, but they certainly have a much lower threshold to image people, to do advanced imaging like CT of any part of the patient really, but specifically brain. P6 R

The specialty of emergency medicine in Australia involves looking after patients more definitively and for a longer period of time than UK where it's more of a triage system. There's more of an emphasis in the UK of which destination the patient's going to in terms of home or surgeons or medicine or so on, whereas here we're involved in more long-term care of patients. … we have greater access to imaging in Australia … compared to the UK … But there was also a lot more oversight of CT cross sectional imaging, so all scans had to be approved by a radiology registrar so they couldn't be ordered by an emergency physician. Here non contrast scans for CT can be ordered by a consultant during the day or a registrar … overnight and scans with contrast need to be approved. P13 R

Local System

Resources

I suppose access to resources, I mean, I think I may have touched on this already, but we are very lucky here on the [health service] that we’ve got excellent facilities and access to them 24/7. Sometimes it’s a little bit different in [smaller hospital] for example where you haven’t got CT on site. P1 R

They're [CT scans] so easy to do and we have such easy access to them and I wonder if having a CT scanner in the ED makes it easy. That's great for when you have trauma and stuff, but I wonder does that also encourage misuse of it. … I don't want to work in a system where I have to fight for every scan, but I do think that there needs to be some policing that we're not just running these people through the scanner again and again without any benefit to the patient. P6 R

Bed flow

but I must admit, when I do make decisions on when to scan someone's—do a CT head if they've had a fall, in an older patient sometimes I do decide to scan more readily if it's going to aid a faster disposition for that patient rather than to need a four-hour period of observation. P7 C

If we'd decided to scan that patient, they would have waited for the CT scan itself, it might be an hour; they would have waited for the result of the CT scan, that might be another hour. That adds two hours for them staying in the department, it's an area that then can't be used for other patients, so it does have cost implications, but even more than that it has implications on flow for the department and that is I think very important. Sometimes in certain patients it can be a helpful thing to get a scan done early because it helps facilitate their discharge but in other patients it holds them in the department and disrupts the flow. P13 R

Cost

Admission and lenghth of stay

If the scan is going to enable an early disposition for the patient, I think it's going to be cheaper to do the scan than to have them clog up a bed for four hours and then require further follow-up potentially in the community as well in terms of GP follow-up. P7 C

Braod sense

I do think about cost and time, and it's not just the individual aspect of that particular patient. Because the Department as a whole, for example, you only have one CT scanner. Scanning one person that may not need it means that you're delaying a scan for someone else and that's all money and time as well. Every minute spent in the ED is also money, but yet again the scan could cost a few hundred dollars, but that could mean as well [to] save time for the patient to be in the ED which is also a lot of money. … So you just go by what you think it’s probably the most efficient way without a lot of information. … It's not just whether we can do something about it surgically, even the outside hospital aspect does cost money if the family's not getting closure, they've got a lot of stress in their life from it, they are not working and it has other impacts beyond, I feel. P21 R