The Canadian Cardiovascular Society and the European Society of Cardiology recommend the use of non-vitamin K antagonists (NOAC) in preference to warfarin for stroke prevention in most patients with non-valvular atrial fibrillation (AF). The aim of this study was to identify factors that predict selection of a NOAC by resident physicians when faced with patients with non-valvular AF. A web-based survey was distributed to residents across Canada to learn the attitudes and behaviours regarding stroke, bleeding risk and choices of therapy in different clinical scenarios involving the same patient and one additional co-morbidity. There were a total of 1014 respondents. In an uncomplicated patient with a new diagnosis of AF, self-reported comfort level was the strongest positive predictor for selecting a NOAC (odds ratio (OR) 2.51; 95% confident interval (CI) 1.79-3.54). Residents’ desire for the availability of a reversal agent was a negative predictor (OR 0.55; 95%CI 0.39-0.77). In a patient with a prior gastrointestinal bleed, each additional year of training was associated with a choosing a NOAC (OR 1.3; 95%CI 1.1-1.5). In the same patient, the desire for the availability of a reversal agent was a negative predictor of selecting a NOAC (OR 0.42; 95%CI 0.32-0.56). The most consistent predictor for prescribing a NOAC in all clinical scenarios was self-reported comfort level. Fear of adverse events, cost of agents and dosing convenience were not significant predictors. This study found that resident physicians’ adherence to guideline-preferred management of AF with regards to stroke prevention is strongly associated with self-reported comfort level, training year and the desire for the presence of a reversal agent.