How dangerous is a day in hospital?: A model of adverse events and length of stay for medical inpatients.

The epidemiology of medical error has been intensively investigated in prior studies, with the goal of quantifying the overall burden of preventable harm on a population basis. This study uses econometric techniques to address a related but distinct question: what is the daily risk of a patient safety event for a typical hospitalized patient? The authors arrive at estimates of the daily risk of various safety problems, including adverse drug events, pressure ulcers, and hospital-acquired infections, and also find that the probability of experiencing an adverse event increases with increasing hospital length of stay.