At the core of the problem is the difficulty in connecting performance of an imaging test to a health-related outcome. Patients rarely live or die on the basis of performance of a noninvasive test. Instead imaging outcomes (if assessed at all) are generally evaluated in a hierarchical fashion that includes the intermediate, but hard to measure, steps of impact on diagnostic and therapeutic thinking (9- 10) (Table 1). In this schema, the initial step in imaging outcomes is technical capability, which generally includes engineering and equipment specifications. This is followed by test performance, which includes conventional measures of sensitivity, specificity, negative and positive predictive values, and overall accuracy, usually determined in reference to a gold standard. Both of these domains are commonly investigated as part of the evaluation of a new imaging test; however, most assessments stop at this stage. Higher levels of imaging outcomes include impact on diagnostic or prognostic thinking (e.g., the patient with a positive stress test result may now be diagnosed with coronary artery disease, and is stratified into a high or low risk group for a future ischemic event). This is followed by impact on diagnostic or therapeutic strategies (e.g., the patient with newly diagnosed coronary artery disease may or may not need additional testing, lipid lowering and other preventive medications should be added or avoided, a therapeutic procedure is indicated or not, and so on). Finally, the highest level involves financial, health-related, and patient and provider satisfaction outcomes (e.g., as a result of testing, will this patient live a longer and healthier life, was the performance of this imaging test a cost-effective strategy for this patient, was the patient’s experience optimal).