The main focus of this study is bridging the "evidence gap" between frontline decision-making in health care and the actual evidence, with the hope of reducing unnecessary diagnostic testing and treatments. From our work in pulmonary embolism (PE) and over ordering of computed tomography pulmonary angiography, we integrated the highly validated Wells' criteria into the electronic health record at two of our major academic tertiary hospitals. The Wells' clinical decision support tool triggered for patients being evaluated for PE and therefore determined a patients' pretest probability for having a PE. There were 12,759 patient visits representing 11,836 patients, 51% had no D-dimer, 41% had a negative D-dimer, and 9% had a positive D-dimer. Our study gave us an opportunity to determine which patients were very low probabilities for PE, with no need for further testing.