Since the release of To Err is Human, health systems have undertaken a multitude of patient safety initiatives to reduce adverse events. Findings from this systematic review demonstrate minimal reduction in overall risk of adverse event rates that can be attributed to implementation of large-scale patient safety initiatives (e.g. Global Trigger tool in inpatient and geriatric settings). The meta-analysis of included studies estimated one adverse event prevented for every 59 hospital admissions. The authors note a need for more research (particularly large-scale implementation studies) to establish the effectiveness of such initiatives.