Without existing data on its use in test populations, however, it is dif cult to JACC Vol. 63, No. 7, 2014 Nallamothu et al. February 25, 2014:722 45 ACC/AHA/SCAI/AMA-PCPI/NCQA know whether the current measure accurately captures appropriateness (as opposed to encouraging gaming) or whether it will lead to unintended consequences by discouraging operators from taking on dif cult or high-risk procedures where, although the risk is high, the bene t could be great (i.e., whether the measure will promote underuse). Concern for this last issue is evident in the evolving processes of the AUC, which have undergone signi cant changes since their early iterations (see below). For these reasons, we designated this measure for internal quality improvement only (see Appendix C for a summary of the writing committee s evaluation). The writing committee also considered addressing the inappropriate indications for elective PCI, as this has been one of the most important features of the AUC. However, the AUC documents speci cally underscore the pivotal role of clinical judgment in determining whether revascu- larization is indicated for an individual patient. The rating of a revascularization as inappropriate by any schematic should not preclude a provider from performing PCI when patient- and condition-speci c data support that decision (11,12). This is re ected in new language; inappropriate has been changed to rarely appropriate. Nevertheless, documentation of the reasons for performing a PCI should still be mandatory. Because the criteria for appropriate indications for elective PCI appear to be, in general, less prone to various interpretations, the writing committee decided to focus on appropriate procedures at the present time. It is certainly possible that measurement of rarely appropriate indications for elective PCI might become part of future performance measures. 5.3. 