Many physicians do not take the time to risk stratify patients and order a d-dimer prior to ordering a CT for pulmonary embolism (PE) . The evidence strongly suggests we can save health care tests, reduce delay and reduce radiation exposure by using a combinatioj of risk stratification and d-dimer. Idea: integrate into Apex a risk stratification tool and require d-dimer testing for all patients with low to moderate pre-test probability before allowing a CT for PE.