Vital signs remain a mainstay of monitoring for deterioration, and early identification of and rapid response to clinical deterioration is critical to preventing patient harm. This observational study used an automated technique to characterize vital sign measurement for nearly 50,000 intensive care unit stays. Investigators found that omission of vital sign recording occurred more than one third of the time. The analysis identified logically inconsistent blood pressure measurements, which suggested data-entry error. The data included a significant proportion of unusual, outlier vital sign values. Taken together, these results demonstrate important inaccuracy in vital sign documentation in the intensive care unit. The authors recommend seeking alternatives to hourly vital sign monitoring in order to optimize safety. A previous WebM&M commmentary discussed challenges in monitoring vital signs.