N ational efforts to improve the quality of care were greatly enhanced by the Institute of Medicine's landmark publication, Crossing the Quality Chasm. 1 The report concludes that a fundamental redesign of the healthcare system is needed to achieve the core needs of health care to be safe, effective, patient-centric, timely, efficient, and equitable. One goal has been to reduce inequity in care by reducing sex, race, and socioeconomic and geographic variability because inequality was felt to represent lack of adherence to optimal standard of care.The Dartmouth Healthcare Atlas project was the first to demonstrate significant regional differences in Medicare spending in the United States without an improvement in quality. 2 This group and others have also shown wide geographic variations in the use of procedures such as coronary angiography and percutaneous coronary angioplasty (PCI). [2][3][4] The causes for this large difference in practice are unclear, but it has been speculated that it is because of both underuse and overuse of these procedures. 5,6 Several factors have been shown to relate to the variation in practice, including the operator, hospital, sex, race, the availability of a cardiac catheterization laboratory, the type of hospital, rural location, the type of health insurance, and socioeconomic class. 3,[7][8][9] Efforts to reduce the variability in care have focused on overuse through adoption of appropriate use criteria (AUC), performance measures, public reporting, and pay for performance.The Rand Corporation first developed AUC in 1986 using a modified Delphi process. Based on guidelines, registry studies, and expert opinion, a panel of experts developed a consensus on several indications for common procedures including angioplasty. 10 The goal of the AUC was to provide guidance on the optimal use of a procedure, to support efficient use of medical resources and to provide a means of assessing practice patterns. The American College of Cardiology Foundation/American Heart Association in collaboration with others have adopted AUC to help improve quality through a reduction in the variability in the use of procedures.The American College of Cardiology Foundation/Society of Cardiac Angiography and Intervention/Society of Thoracic Surgery/American Association for Thoracic Surgery/American Heart Association/American Society of Nuclear Cardiology/Heart Failure Society of America/Society of Cardiovascular Computed Tomography AUC for coronary revascularization were published in 2009 and 2012, and the AUC for cardiac catheterization were published in 2012. [11][12][13] The AUC indications for coronary revascularization is an extensive document that ranked >180 clinical situations using 5 key variables: clinical presentation (acute coronary syndrome or stable angina), severity of angina (Canadian Cardiovascular Society class), extent of ischemia on noninvasive testing, extent of medical therapy, and extent of anatomic coronary disease. Despite the large number of clinical situations evaluated, the criter...