Voluntary error reporting systems have many limitations, ranging from selection bias in reporting to a perception that errors may not be appropriately addressed. A 2008 survey found that only a minority of US hospitals had a structured system for following up on reported events. This mixed-methods study used a combination of surveys, focus groups, and expert panels to define measurements for how organizations respond to patient safety events. The authors defined a set of indicators that evaluate the analysis of the event and the dissemination of learnings from the event. Failure to appropriately address reported errors contributes to normalization of deviance, a "culture of low expectations" that has been implicated in high-profile errors.