Table 3:

Domain 2: Guideline usage for OAC prescribing for new-onset AF at ED discharge

Theme	Subthemes	Representative Quotation
Use of Guidelines & Decision-making Tools		I use the CHADS₂ score for starting people on anticoagulation if they're going to be discharged home. That's a definitely major one that I use, and other than that, I don't use any other scoring system. I base [anticoagulation] on the CHADS score on whether or not they need to be anticoagulated, and often times, they can just go home on an ASA [aspirin] [My decision is] based on my reading of the literature and in part, some of the guidelines from the American Heart [Association]
Barriers to Use	Lack of Consistency in Information and Recommendations	I feel like there's a lot of different information out there from a lot of different sources. [For example,] the EM literature and the cardiology literature. I almost feel like the two aren't necessarily aligned with each other. I think if there was consensus of the American [College] of Emergency Physicians with the cardiologists that said…"we support ER doctors who feel that a patient falls under this category, then that is standard of care."
	Difficult to Use/Lengthy	I find… the decision tools where it's …very lengthy, and there is a lot to remember, I don't use those as much. I don't think a lot of people use those as much. Sometimes institutional protocols can be helpful. Although I think some see them as a bit of hindrance.
	Not ED Specific	I think the challenges remains that …if you ask a cardiologist to manage it, their approach is very different than an ED physician because they look at the long-term follow-up piece. Our issue is short-term and the question is in the short term, is there data to support what we do and is it safe? …When you start to put all those things together, I think the challenge becomes creating a rule which is actually ED pertinent. So the CHADS score is really not ED pertinent and that's the problem with the CHADS score, it's a cardiologist score.
	Lack of Consideration of Comorbidities & Individualized Treatment	[W]e're using protocols, but nobody is thinking outside of the box and when you don't think outside the box, you are not giving good care. I mean we were taught to think. [T]here are usually a fair number of exclusions when they're deriving and validating decision tools but by that I mean that every patient is a unique event and so your patient that is in front of you may or may not fit the population from which the assistant tool was derived. So you have to use some judgement, it's not a universally applicable one-size fits all decision tool, usually. I'll use research or use a guidline depending on the patient because every patient is different. So I don't believe in cookie cutter guidelines for everybody because I think that's robotic care and I think that takes away the art of medicine.
	Awareness	I don’t use guidelines…probably due to a lack of awareness. I don't feel that the patients that I have deviated significantly from the care that I'm used to or am already delivering. A barrier? It would be my education. Not knowing.… My lack of knowing. My lack of reading about it.