Table 3 Barriers and enablers (including belief statements and sample quotes) of fidelity to the proposed intervention delivery for relevant domains

Beliefs about capabilities

I am confident I can deliver this intervention as planned. (Enabler)

How easy or difficult do you think it would be to adhere to delivering say 80% of the intervention components?

“I think it would be pretty easy to do that, yeah.” DC004

6

“I don’t think 80% is too hard.” GP003

I would not be confident in delivering this intervention as planned in certain situations (e.g., pushback from patients, if I had to educate on self-management strategies, if I was limited on time, if patient had other reasons for presenting for care). (Barrier)

“As I had alluded to earlier, my patients rarely ever book an appointment just to talk about their back pain. And so what inevitably would happen, even if we did just book an appointment for their back pain, is that we would get partway through this, and it would make them think about…something else…and then we would end up totally off topic. And so it can be difficult in going through an intervention like this to try to keep it contained, because it’s difficult to keep anything contained, and so that can be tricky.” GP001

5

“I mean…self-management strategies are always a difficult conversation…difficult to deliver to a patient. And reassurance and education. I mean, they’re so important but they are the things that take the longest I find in practice. And often times, patients aren’t always willing to do the self-management techniques at home” DC004

I am confident I can deliver this intervention during my clinic encounter, without being worried about time. (Enabler)

“I can manage to get a lot of the information out in a reasonable amount of time.” GP002

1

Optimism

I believe the proposed intervention delivery enhancement strategies (e.g., algorithm, use of a script) would help me to deliver the intervention. (Enabler)

[On the strategies for enhancing fidelity to intervention delivery]

“I like all of them.” DC003

4

“I think it’s great. I love algorithms.” GP004

“I like the script idea.” DC003

“[Self-management strategies] is the part I look most forward to. That’s the part I want the most out of. Because like I said, patients don’t get an x-ray but then they leave with some really good information of things that they can do to help with their cause. So that’s the thing that would get you the buy in for the whole program.” GP003

Goals

It is important for me to deliver the intervention as planned. (Enabler)

[On the importance of delivering the intervention as planned]

“It’s very important. I think it’s very necessary.” DC002

7

Delivering this intervention as intended is only important to me if I believe non-indicated imaging is an important issue and if the intervention aligns with the appropriate standard of care I provide. (Barrier)

“How big of a problem a particular individual provider views imaging for lower back pain…how important they think it is to their practice is going to decide whether or not they use the tool or are committed to it.” GP001

2

“I think that my priority is always am I giving the standard of care that’s appropriate to the clinical situation to my patient. So if this situation looked like it would be appropriate to fit the intervention, then I would use the intervention to the best that I could to meet the clinical scenario.” GP005

Memory, attention, and decision processes

Features of the training for this intervention (e.g., in-person training session, use of role play, training manual, booster sessions) would help me remember how to deliver the intervention as intended. (Enabler)

“But I’m a sucker for having everybody on the same page, so to have a session and know that everybody’s there and everybody’s kind of paying attention and really invested in it.” DC003

6

“I mean, there’s no question role playing is very important. I mean, you could read something and it just quickly dissipates from your brain as time goes. And if you solidify that with a concrete learning example like role playing, I think it’s essential.” DC005

[On the importance of a training manual]

“Then if I do this once every 3 months or once every 9 months, I don’t have to try to remember what I did at the last session, but I could quickly go in 2 min and review things myself, and then it’s very fresh when I see the patient. So to me, for someone who’s busy, that would be super super helpful.” GP004

“But definitely, the regular booster sessions as well help if it’s a study that’s going over a long period of time. People sort of lose and forget what they’re doing and sometimes just that meeting to make sure people are still on the right track is good.” GP002

Proposed features of the intervention (e.g., algorithm, script for delivery or patient discussions, session checklist) and reminders of the intervention components built into the electronic medical record would help me remember how to deliver the intervention as intended. (Enabler)

“The clinical resource is a definite huge bonus. Anything you can reach to quickly give yourself a refresher or make sure you’ve checked all your bases is nice.” DC003

4

“Having a checklist as part of the resource, that these are your main talking points and I’ve got it printed out or pinned up in the office that if the conversation comes up, I can look it over” DC003

“But I think just having a little bit of detail on the EMR, it would probably make sure that people remember it [the components of the intervention]” GP004

“The script for delivery is actually not bad because after a time, it becomes part of your normal lingo, right? So you start off sort of mechanically, I guess, in a way. Sort of saying ‘this is what we’re doing blah blah blah’. It eventually becomes part of what your dialogue is.” GP002

I may not deliver the intervention as intended because I already have or will develop my own way of explaining concepts around imaging and LBP. (Barrier)

“I think too, once I’ve implemented it, like for example, once I’ve used the tool, let’s say we use the clinician decision tool. Once I’ve used it once or twice, I don’t need to bring it up every time, because I’ve got it right? So like, the main part would be like, I guess…because it’s very much dependent on the patient. So like there’s some flexibility in how that program is also delivered. So like, did I use the decision making tool today? Well I didn’t take out the decision making tool and look at it, but I did use it in my head.” GP003

3

“I think similar to before, just having this become your autopilot vs. what I use right now when this conversation comes up. It’s remembering to switch to this, which I guess in reality, is not too far different from what I already do, but for some people, maybe it would be a bit different.” DC003

I may not deliver the intervention as intended if it takes too much of my time. (Barrier)

“But the moment it becomes cumbersome or takes more time, because time is ultimately the factor that not a lot of us have a lot of, and the moment that it becomes more time to do it, it will become less utilised properly.” GP003

2

Environmental context and resources

Lack of time may be a barrier to delivering the intervention as planned. (Barrier)

“The biggest problem when it comes to clinical resources or decision tools or whatnot in family medicine is that we don’t have any time.” GP001

6

“Time would definitely be a challenge. As a chiropractor, I know most only spend about 20 min with their patient and that’s for a quick re-assessment, a conversation, and treatment.” DC004

Time is not a barrier to delivering the intervention as planned. (Enabler)

“I’m not in fee-for-service anymore so I have the time to explain things well.” GP004

1

Social influences

Patient pressure to order imaging will not prevent me from delivering this intervention. (Enabler)

[On patients being persistent on getting an x-ray]

“There’s some, but usually, when you talk about it, they come around to it.” GP002

5

“I think that would be something to contend with, but I don’t think it would prevent me from [delivering the intervention]” DC001

Patient pressure for imaging may influence my ability to deliver this intervention as intended. (Barrier)

“Because ultimately, I find, it’s not my clinical decision tools to know whether or not to do an x-ray that’s the issue. My issue is the patient demanding to have an x-ray. That is ultimately what it brings it down to. … sometimes it’s easier to not fight the fight and just say ‘Here’s your x-ray because you’re not going to leave until you get one anyways’.” GP003

3

“But you’ll always hit difficult people who want what they want regardless of whether it’s going to be the most effective resource for them. So I think the biggest challenge you’ll get is just personality or patient types.” DC003

Behavioural regulation

An intervention script with key talking points (that isn't too prescriptive) would help me to deliver the intervention as intended. (Enabler)

“Every practitioner has their own style of delivery. Just key points that have to be delivered. I think that would be the best way to do it.” DC002

10

“Every person is their own illness experience. Not everybody experiences low back pain the same way. … And I agree there’s some people who would find that this is difficult to understand, so that may make it a bit of a challenge to delivering this – patients themselves. So you need to have a little bit of flexibility in the script and how you’re delivering it.” GP002

“I think speaking points because you would make your own way in how to do it. But you want to be able to touch on all the main things that you want to get into the session.” GP003

I think having regular check-in times (e.g., booster sessions, progress check-in emails) and/or the ability to reach out to the research team (e.g., clinical coach or project champion) when needed would help me to deliver this intervention as intended. (Enabler)

“I really like the idea of a booster session. It makes a lot of sense. There are so many CME events that I go to and then I get all excited and I take it away and then I go to implement it into my practice and then it kind of falls apart… And a booster session that includes a component of bringing back difficult encounters or you know… ‘I tried to use this tool on this patient and here’s what happened. How could I approach that better next time or what did I do wrong?’. I think that would be very useful. … I think you have 1 booster session maybe 6–8 weeks out and that would be the best that we would be able to hope for when it comes to buy in and engaging people right now.” GP001

10

“I think having a champion is a really good idea … if you had somebody that basically said ‘I’m trained up on this. I’m happy and interested in helping’.” GP001

“Having that touch base call every 4–6 weeks sometimes does get people get back on track and make them think about what the purpose of this is and the flow and answer any questions that they may have.” GP002

“I don’t know if I would spend time putting on a booster session. I would more say, ‘This is our contact information. If you have an issue, then reach out to us.’.” GP003

[On receiving support from the research team]

“Regular emails, just reaching out to see if they need any assistance, see how their progression is.” DC002

Tailoring the intervention to fit within a regular appointment time (5–10 min for GPs; 15–20 min for DCs) will help me to deliver the intervention as intended. (Enabler)

“If [LBP] were the only thing in the appointment, it would be ideal. Because in that case, then you could go through the whole thing about the indications and the education and the thing goes along with it, and then running through some of the interventions that they can do themselves to get started.” GP002

5

“I think if the script could be honed enough that it could be all done in 15–20 min for us anyways. It would be about fitting it into an appointment time.” DC001

Flexibility in intervention material formats (e.g., access to both digital and paper copies with the possibility of having digital copies built into the electronic medical record) would help me to use the materials as intended. (Enabler)

“What I’m picturing is in the EMR or on a website, you can just bring up the tool and print it right from the computer. That way if you’re moving around multiple clinic rooms and things, you don’t have to have multiple booklets and they get lost and stuff like that.” GP001

3

“I’d say most people are pretty tech savvy at this point. So I’ve had good success with links and stuff, or just recommending go on YouTube and search this. Just the ease of being able to send that off. But a hard copy is…it’s easy to give out and there’s no barrier at that point. For anybody who doesn’t have access to Internet or just doesn’t go on as much to it. It eliminates all barriers.” DC003