The writing committee considered a measure of assessment of angina. Given that one of the primary reasons for perform- ing PCI is to reduce angina, the concept of assessing anginal class in a structured way before PCI, and reassessing it in the same way after PCI, has intuitive appeal. However, the writing committee noted several challenges. First, it was recognized that angina/ischemia can present in different ways, and there was little agreement on how to account for unusual symptoms presenting as an anginal equivalent. Second, it was recog- nized that rigorous, standardized anginal class assessment (eg, the Seattle Angina Questionnaire), though standard in clinical trials, is not typically performed in the clinical setting, and that more common systems, like the Canadian Classification System, have poor reliability and are too subjective. These issues created a tension between the feasibility of a measure related to angina assessment and its usefulness. For these rea- sons, the writing committee decided not to include an assess- ment of angina in the present set, but it believes this should be an area of future development. 6.2.2. Thirty-Day Mortality Rate The writing committee considered a mortality measure, and the 30-day endpoint was discussed in particular, because this was identified as the time point (as opposed to 1 year) at which outcomes would be most closely related to the index proce- dure. For the reasons discussed in Section 4.2, death as an outcome measure has obvious appeal. It is overall an unam- biguous and unarguable endpoint and, along with stroke, is generally considered one of the worst possible outcomes of a PCI procedure. The challenges to using 30-day mortality rate as a performance measure relate primarily to risk-adjustment issues, and 2 main sentiments prevailed: 1) There was a strong desire to avoid penalizing operators for taking difficult cases. 