More than one-third of medical care is thought to be wasteful, and much of the unnecessary care stems from overuse of services that do not appear to improve clinical outcomes.1 The rising cost of health care in the United States has prompted interest in reducing wasteful spending. Policymakers and professional societies have proposed and implemented numerous strategies to decrease overuse (eg, the publication of evidence-based guidelines, developing Top Five lists, alternative payment models such as accountable care organizations that aim to reward quality rather than volume, and pay-for-performance programs); however, unnecessary care persists.