OBJECTIVES:Providers often pursue imaging in patients at low risk of pulmonary embolism (PE), resulting in imaging yields <10% and false-positive imaging rates of 10% to 25%. Attempts to curb overtesting have had only modest success and no interventions have used implementation science frameworks. The objective of this study was to identify barriers and facilitators to the adoption of evidence-based diagnostic testing for PE. METHODS:We conducted semistructured interviews with a purposeful sample of providers. An interview guide was developed using the implementation science frameworks, consolidated framework for implementation research, and theoretical domains framework. Interviews were recorded, transcribed, and analyzed in an iterative process. Emergent themes were identified, discussed, and organized. RESULTS:We interviewed 23 providers from four hospital systems, and participants were diverse with regard to years in practice and practice setting. Barriers were predominately at the provider level and included lack of knowledge of the tools, particularly misunderstanding of the validated scoring systems in Wells, as well as risk avoidance and need for certainty. Barriers to prior implementation strategies included the perception of a clinical decision support (CDS) tool for PE as adding steps with little value; most participants reported that they overrode CDS interventions because they had already made the decision. All providers identified institution-level strategies as facilitators to use, including endorsed guidelines, audit feedback with peer comparison about imaging yield, and peer pressure. CONCLUSIONS:This exploration of the use of risk stratification tools in the evaluation of PE found that barriers to use primarily exist at the provider level, whereas facilitators to the use of these tools are largely perceived at the level of the institution. Future efforts to promote the evidence-based diagnosis of PE should be informed by these determinants.