relation between PIMs and adverse events, length of stay, discharge to higher levels of care, or in-hospital mortality. Schamder et al 4 reduced PIM use among hospitalized patients, but this reduction did not result in fewer adverse reactions.Inappropriate use of medications is problematic, but most medication-related harms do not involve PIMs. All together, more than 40 generally recognized PIMs cause an estimated 3.6% of emergency department visits for adverse events among US older adults, while just 3 other drugs (warfarin, insulin, and digoxin) account for 10 times more visits. 5 In the hospital setting, approximately 40% of Medicare patients are treated with anticoagulation and warfarin, heparin, and low-molecular weight heparins are associated with adverse events in 8.2%, 13.6%, and 9.6% of these patients, respectively. 6 Fittingly, reducing harm from anticoagulation is a Joint Commission national patient safety goal. 7 As another example, hospitalacquired, hospital-onset Clostridium difficile infections cause an estimated 165 000 cases, 9000 deaths, and $1.3 billion in excess costs in the United States annually, and one of the most crucial modifiable factors in their prevention is antimicrobial overuse. 8 While C difficile infections and anticoagulant adverse events cannot be prevented with simple prescribing alerts alone, until studies demonstrate that reductions in PIM use substantially improve patient safety outcomes, future health information technology innovations should focus on such issues that are consistently linked to common, serious, and preventable harms rather than on narrow metrics of pharmacologic appropriateness lacking clinical context.