De nition and Selection of Measures The writing committee reviewed both recent guidelines and other clinical guidance documents, such as the ACCF/ Appropriate Use Criteria for Coronary Revascularization (11). The writing committee also examined available information on gaps in care and the clinical epidemiology of PCI. All measures were designed to assess quality of care in pa- tients undergoing PCI across a variety of ambulatory and hos- pital settings to support achievement of the desirable outcomes identi ed. The measures also were designed to allow for the exclusion of patients with contraindications or other valid rea- sons for exclusion from the measure. In de ning the measure exceptions, the writing committee was guided by the AMA- PCPI Recommendations for Speci cation and Categoriza- tion of Measure Exclusions (13), as discussed further below. The writing committee evaluated the potential measures against the ACC/AHA attributes of performance measures (Table 4) to reach consensus on which measures should be advanced for inclusion in the nal measure set; the Summary Analysis Table (Appendix C) captures this evaluation process. After the peer review and public comment period, the writing committee reviewed and discussed the comments received, and further re nements were made in the measure set. 2013 Percutaneous Coronary Intervention Measures 3.1. Target Population and Care Period The target population for the measures consists of all patients undergoing PCI for coronary artery disease. That said, a large focus of the writing committee was on measures aimed at patients coming to the cardiac cath- eterization laboratory for elective proceduresdthat is, those originating as outpatients. Patients arriving from the inpatient setting or emergency department and those with acute coronary syndromes were considered second- arily. The writing committee decided on this approach for 2 reasons. 