RT Journal A1 Chan PS, Spertus JA T1 UNderuse of percutaneous coronary intervention—reply JF JAMA JO JAMA YR 2011 FD November 16 VO 306 IS 19 SP 2094 OP 2095 DO 10.1001/jama.2011.1659 UL http://dx.doi.org/10.1001/jama.2011.1659 AB In Reply: Dr Restuccia and colleagues are correct in noting that threats to the quality of PCI include underuse, overuse (which we examined), and misuse (performing the procedure poorly1 in those who appropriately receive it). We believe that underuse is an important problem that warrants further research. Hemingway et al2 have suggested that failure to perform revascularization in appropriate patients can be associated with poorer outcomes. Further insight into underuse, however, will require a different methodology than what has been applied in prior studies.