Identifying incipient clinical deterioration is a prerequisite for rapid response and prevention of harm for hospitalized patients. This study tested a bedside pediatric early warning system, which included an illness severity score, standardized documentation, and monitoring protocols. In a cluster-randomized trial in several high-income countries, implementation of the bundle did not result in decreased in-hospital mortality compared to usual care. The overall mortality rate in the study was less than 0.2%. The authors suggest that this unexpectedly low mortality rate may have made it difficult to detect differences in intervention versus control hospitals. A related editorial suggests that artificial intelligence should be used to identify clinical deterioration and that outcomes beyond mortality should be considered in their evaluation.