, fractional ow reserve, intravascular ultrasound) and noncoronary pro- cedures (e.g., transcatheter aortic valve replacement) should be included in these assessments of operator and institu- tional volume, given that these techniques require over- lapping technical skills. 6. Potential Measures Considered But Not Included in This Set 6.1. Process Measures The writing committee considered several additional pro- cess measures for inclusion. A longitudinal measure assessing use of dual-antiplatelet therapy at 30 days and 1 year was considered. Although such a measure has a greater likelihood of improving care, the logistical challenges of collecting longitudinal drug data on an outpatient basis made it dif cult to implement this measure at the present time. We are hopeful that advances in information tech- nology, electronic health records, and outpatient registries will make reliably collecting these data possible in the future. We also examined additional measures related to ad hoc PCI (PCI performed during the same session as diagnostic angiogram) and multivessel PCI. These measures focused on examining the core question of whether the PCI was appropriate in the context of additional therapeutic op- tions, like medical therapy and coronary artery bypass surgery. This was an area of great interest and much dis- cussion for the writing committee. However, in the end the group felt limited in our ability to construct feasible mea- sures that could be applied reliably in clinical practice. We decided that these topics were ultimately beyond the charge of a writing committee focused on PCI. Our greatest barriers were the lack of de nitive data on the risks and bene ts of ad hoc PCI and multivessel PCI and their role in shared decision making by patients and providers (49,50). 