Health care systems around the world are under pressure to restrain health care expenditures. In response, many health care leaders have embraced the idea of promoting health care value, with value defined “as the healthcare outcomes achieved per dollar spent.”1 For instance, some experts have urged third-party payers to adopt value-based insurance designs, whereby the amount patients pay out-of-pocket for health care services varies not as a function of the cost of those services but, instead, as a function of their value.2